SEMICONDUCTOR STRUCTURE AND METHOD FOR PREPARING
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`SAME
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`CROSS-REFERENCE TO RELATED APPLICATIONS
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`[ 0001]
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`This application is a U.S. continuation application of International Application
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`No. PCT/CN2022/078108, filed February 25, 2022, which claims priority to Chinese
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`Patent Application No. 202210032642.4,filed January 12, 2022. International Application
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`No. PCT/CN2022/078108 and Chinese Patent Application No. 202210032642.4 are
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`incorporated herein by reference in their entireties.
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`BACKGROUND
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`[ 0002]
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`With the development of 3D packaging technology, multi-layer stack packaging
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`technology is widely used, but the multi-layer stacked structure needs wafers with a same
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`size to stack. The connection structure between wafers will occupy a certain thickness of
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`the multi-layer stacked structure, which will increase the overall thickness of the multi-
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`layer stack structure, and thus cannot meet the need of thinner and thinner terminals.
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`[ 0003]
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`In addition, with the continuous miniaturization of integration,
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`the size of
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`connection structures in the multilayer stacked structure is getting smaller and smaller, and
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`the distance between adjacent connection structures is getting smaller and smaller, which
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`easily leads to short circuit between adjacent connection structures and wafer-to-wafer
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`shedding.
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`SUMMARY
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`[ 0004]
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`The embodiments of the disclosure relate to the semiconductor field, and in
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`particular to a semiconductor structure and a method for preparing the same.
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`

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`[ 0005]
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`According to some embodiments of the disclosure, one aspect of
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`the
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`embodiments of the disclosure provides a semiconductorstructure including: a first base
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`having a first face, a second base having a second face and a weldedstructure. The first
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`base is provided with an electrical connection column protruding from the first face. A
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`conductive column is provided in the second base. A first groove and a second groove are
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`further providedat the second face. The first groove communicates with the second groove.
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`The first groove is located above the conductive column and exposesat least a part of a
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`top surface of the conductive column, and the second groove exposesat least a part of a
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`side surface of the conductive column. The second face is bonded to the first face. The
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`protruding portion of the electrical connection column is located in the second groove, and
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`a part of a side surface of the electrical connection column and a part of a side surface of
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`the conductive column overlap in a staggered way in a direction perpendicularto thefirst
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`face or the second face. Atleast a part of the weldedstructureis filled in the first groove,
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`and at least a further part of the welded structure is located between the electrical
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`connection column and a bottom surface of the second groove.
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`[ 0006]
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`According to some embodiments of the disclosure, another aspect of the
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`embodiments of the disclosure also provides a method for preparing a semiconductor
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`structure, including the following operations. A first base having a first face is provided.
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`The first base is provided with an electrical connection column protruding from thefirst
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`face. A second base having a second face is provided. A conductive column is provided in
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`the second base. A first groove and a second grooveare further provided at the second face.
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`The first groove communicates with the second groove. The first groove is located above
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`the conductive column and exposesat least a part of a top surface of the conductive column,
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`and the second groove exposesat least a part of a side surface of the conductive column.
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`The second face is bonded to the first face. The protruding portion of the electrical
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`connection column is located in the second groove, and a part of a side surface of the
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`electrical connection column and a part of the side surface of the conductive column
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`overlaps in a staggered way in a direction perpendicularto the first face or the second face.
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`Atleast a part of the weldedstructureis filled in the first groove, and at least a further part
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`of the welded structure is also located between the electrical connection column and a
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`bottom surface of the second groove.
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`

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`BRIEF DESCRIPTION OF THE DRAWINGS
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`[ 0007]
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`One or more embodiments are illustrated by the pictures in the drawings
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`corresponding thereto. These exemplary descriptions do not constitute a limitation on the
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`embodiments. Unless otherwisestated, the figures in the drawings do not constitute a scale
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`limitation.
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`[ 0008]
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`FIG. 1 is a schematic structural diagram of a semiconductorstructure provided
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`by an embodimentof the disclosure; and
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`[ 0009]
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`FIGs. 2 to 13 are schematic structural diagrams corresponding to each step of a
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`method for preparing a semiconductor structure provided by an embodiment of the
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`disclosure.
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`DETAILED DESCRIPTION
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`[ 0010]
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`It can be seen from the backgroundthat with the continuous miniaturization of
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`the integration, a size of a connection structure in a multi-layer stacked structure becomes
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`smaller and smaller, and the spacing between adjacent connection structures becomes
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`smaller and smaller. However, the small spacing between the connection structures may
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`lead to lapping between the adjacent connection structures, and further lead to short circuit
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`between the adjacent connection structures.
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`[ 0011]
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`By analysis, it is found that a TCB-NCF thermo-compression bonding process
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`is usually used in the current packaging technology of stacked bases. The TCB (Thermo
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`Compression Bonding) uses heating and pressurizing to form welding at the connection
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`structure between two adjacent bases so as to realize the connection between the adjacent
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`bases. The NCF (Non Conduction Adhesive Film) works in cooperation with the TCB
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`process. That is, NCF is coated between two bases, and NCFis usedasafilling material
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`to fill in the gap between the two bases and wrap the connection structures protruding from
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`the bases.
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`

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`[ 0012]
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`However, due to the special fluidity of NCF material, it is impossible to give a
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`manufacturing process with an enough strength to the connection structure. The shape of
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`the connection structure is easy to shift under force, which makes the connection between
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`adjacent bases unstable. Moreover, the shape of the connection structure is easy to shift
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`under force, making readily the shape of the connection structure abnormal, which may
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`lead to a dislocation at the joint between bases, thereby reducing the signal transmission
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`efficiency between adjacent bases, and may also lead to short circuit due to contacting
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`between adjacent connection structures. In addition, due to the addition of NCF materials
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`between the bases, an overall thickness of the stacked bases is increased, which is not
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`suitable for the current demandthat the terminals are getting thinner and thinner.
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`[ 0013]
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`The embodiments of the disclosure provide a semiconductorstructure in which
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`a bonding between a first base and a second base can be tightened and the height of the
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`whole semiconductor structure can be reduced by arranging a protruding portion of an
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`electrical connection column in a second groove. By arranging a weldedstructure in a first
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`groove and the second groove, the flow of the welded structure in the bonding process,
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`which leads to the interconnection of adjacent electrical connection columnsor conductive
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`columns, can be avoided. The reliability of the semiconductor structure can also be
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`improved by arranging the welded structure in the first groove and the second groove.
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`Moreover, by reducing the use of the NCF material, the material consumption can be
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`reduced and the height of the entire semiconductor structure can be reduced, and the
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`occurrence of a short circuit caused by contact of adjacent connection structures due to the
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`use of the NCF material can also be avoided.
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`[ 0014]
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`The embodiments of the disclosure will be described in detail below with
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`reference to the accompanying drawings. However one of ordinary skill in the art will
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`appreciate that numeroustechnical details are set forth in the various embodiments of the
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`disclosure in order to enable the reader to better understand the embodiments of the
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`disclosure. However, even without
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`these technical details and various changes and
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`modifications based on the following embodiments, the technical solutions claimed by the
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`embodiments in this disclosure can be realized.
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`[ 0015]
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`FIG. 1 is a schematic structural diagram of a semiconductor structure provided
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`

`

`by an embodimentof the disclosure.
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`[ 0016]
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`Referring to FIG. 1 the semiconductorstructure includesa first base 110 having
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`a first face 100, a second base 140 having a second face 130 and a welded structure 180.
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`The first base 110 is provided with an electrical connection column 120 protruding from
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`the first face 100. A conductive column 150 is provided in the second base 140. A first
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`groove 160 and a second groove 170 are further provided at the second face 130. Thefirst
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`groove 160 communicates with the second groove 170. The first groove 160 is located
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`above the conductive column 150 and exposes at least part of a top surface of the
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`conductive column 150. The second groove 170 exposesat least part of a side surface of
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`the conductive column 150. The second face 130 is bonded to the first face 100. The
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`protruding portion of the electrical connection column 120 is located in the second groove
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`170, and a part of the side surface of the electrical connection column 120 anda part of the
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`side surface of the conductive column 150 overlap in a staggered way in a direction
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`perpendicular to the first face 100 or the second face 130. At least a part of the welded
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`structure 180 is filled in the first groove 160, and at least a further part of the welded
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`structure 180 is located between the electrical connection column 120 and the bottom
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`surface of the second groove 170.
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`[ 0017]
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`In some embodiments, the first base 110 and the second base 140 may both be a
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`wafer, and the semiconductor structure may be a wafer-stacked structure.
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`In other
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`embodiments, the first base 110 and the second base 140 mayalso both be a die, and the
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`semiconductorstructure may be a die-stacked structure. Further, in yet other embodiments,
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`one of the first base 110 and the second base 140 may be a wafer, and the other may be a
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`die.
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`[ 0018]
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`Specifically, in some embodiments, the first base 110 may include a passivation
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`layer 111, a conductive layer 112 and a substrate 113.
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`[ 0019]
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`In some embodiments,
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`the passivation layer 111 covers the surface of the
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`substrate 113 facing the passivation layer 111, and the passivation layer 111 also covers
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`part of the surface of the conductive layer 112. The passivation layer 111 is configured to
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`protect the conductive layer 112 and the substrate 113, preventing the conductive layer 112
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`and the substrate 113 from contacting other structures, thereby improving the stability of
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`

`

`the semiconductor structure. The conductive layer 112 is located in the substrate 113, and
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`the substrate 113 exposes the surface of the conductive layer 112. The conductive layer
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`112 is configured to electrically connect the electrical connection column 120 with other
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`structures in the first base 110.
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`[ 0020]
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`In some embodiments, the material of passivation layer 111 may be an insulating
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`material with a high relative dielectric constant such as silicon nitride, silicon nitride or
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`silicon oxynitride. The material of conductive layer 112 may be a conductive material such
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`as aluminum,silver or gold. The material type of the substrate 113 may be an elemental
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`semiconductor material or a crystalline inorganic compound semiconductor material. The
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`elemental semiconductor material may be silicon or germanium, and the crystalline
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`inorganic compound semiconductor material can be silicon carbide, silicon germanium,
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`gallium arsenide, indium gallium andthelike.
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`[ 0021]
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`In some embodiments, the electrical connection column 120 is located on the
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`surface of the conductive layer 112 and electrically connected with conductive layer 112.
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`The electrical signals of the conductive layer 112 are led out through the electrical
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`connection column 120. In other embodiments, part of electrical connection column 120
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`may also be embedded in the conductive layer 112. In yet other embodiments, the electrical
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`connection column mayalso penetrate the conductive layer and electrically connect with
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`the conductive layer through the sidewalls of the electrical connection column.
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`[ 0022]
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`The height of the semiconductor structure can be reduced by disposing the
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`electrical connection column 120 in the second groove 170. The welded structure 180 can
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`be confined by arranging the welded structure 180 in the first groove 160 and the second
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`groove 170, so as to avoid the lap between adjacent electrical connection columns 120 or
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`adjacent conductive columns 150 caused by the flow of the welded structure 180, thereby
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`reducing the possibility of short circuit of the semiconductor structure. The connection
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`between the first base 110 and the second base 140 can betightenedbyfilling the welded
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`structure 180 around the electrical connection column 120,
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`thereby improving the
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`connection tightness of the semiconductorstructure.
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`[ 0023]
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`In some embodiments, the electrical connection column 120 may include a
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`conductive body 121, a first diffusion barrier layer 122 located on the bottom and side
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`

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`surfaces of the conductive body 121, and a first metal protective layer 123 located on the
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`top surface of the conductive body 121. The first metal protective layer 123 is located
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`between the conductive body 121 and the welded structure 180, and a part of the
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`conductive body 121 located in the second groove 170.
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`[ 0024]
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`In some embodiments, the conductive body 121 may be configured to realize
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`signal transmission betweenthe first base 110 and the second base 140.
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`[ 0025]
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`Thefirst diffusion barrier layer 122 may be higher than the conductive body 121.
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`The first diffusion barrier layer 122 may prevent partial ions of the copper metal in the
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`conductive body 121 from entering the first base 110 during ion diffusion, preventing the
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`conductive body 121 from contaminating the first base 110,
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`thereby improving the
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`performance of the entire semiconductor structure. The first metal protective layer 123 is
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`located on the surface of the conductive body 121 facing the second groove 170, and the
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`first metal protective layer 123 may also cover inner walls of a part of the first diffusion
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`barrier layer 122 higher than the conductive body 121. The first metal protective layer 123
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`is configured to protect the conductive body 121 from contacting with air, preventing a
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`part of the conductive body 121 from reacting with air, thereby preventing the part of the
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`conductive body 121 from being oxidized. The conductive body 121 can be separated from
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`air by the first metal protective layer 123, thereby avoiding oxidation or water vapor
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`corrosion of the conductive body 121. The first metal protective layer 123 can also be
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`configured to prevent the conductive body 121 from contaminating the second base 140 in
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`the process of ion diffusion.
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`[ 0026]
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`In some embodiments, the material of the conductive body 121 includes copper
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`or aluminum, and the material of the first diffusion barrier layer 122 includes tantalum,
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`titanium, titanium nitride or tantalum nitride.
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`[ 0027]
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`It will be understood that the copper material and the aluminum material have a
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`good electrical conductivity, and the price of the materials themselves is low, which is
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`conducive to reducing the cost of semiconductorstructure while ensuring a goodelectrical
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`conductivity. As an example where the material of the first diffusion barrier layer 122 is
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`titanium nitride, by forming a titanium nitride layer on the surface of the conductive body
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`121, the grain boundaries and various defects of a part of the conductive body 121 can be
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`

`

`filled, thereby blocking a rapid diffusion path of atoms. In some embodiments, a laminated
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`structure of a titanium nitride layer and a tantalum layer may be formedasthefirst diffusion
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`barrier layer 122. The barrier characteristics of the first diffusion barrier layer 122 can be
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`improvedby the laminated structure of the titanium nitride layer and the tantalum layer.
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`[ 0028]
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`In some embodiments, the first diffusion barrier layer 122 and the first metal
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`protective layer 123 also have portions protruding from the top surface of the conductive
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`body 121.
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`[ 0029]
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`An accommodation space can be formed by the portions protruding from the top
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`surface of the conductive body 121, thereby providing convenience for the processing
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`technology of forming the semiconductor structure. That is, it is convenient for an initial
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`welded structure to have a certain initial shape on the top surface of the first metal
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`protective layer 123, so as to prevent from being present on the surface of the passivation
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`layer 111 before bonding the first base 110 to the second base 140. Thus, it is avoided that
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`excessive initial welding structure present on the surface of passivation layer 111 affects
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`the surface attachmentofthe first face 100 to the second face 130. The total volumeof the
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`welded structure 180 can be indirectly controlled by forming the accommodation space.
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`The lack of the welded structure 180 during bonding of the first base 110 to the second
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`base 140 can be avoided by controlling the total volume of the welded structure 180. The
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`stability of the connection between the first base 110 and the second base 140 can be
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`improved by controlling the total volume of the welded structure 180. Moreover, by
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`controlling the total volume of the welded structure 180, the welded structure 180 can be
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`prevented from being too much dueto a too large total volume of the welded structure 180.
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`Otherwise, during bonding the first base 110 to the second base 140, a part of the welded
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`structure 180 may overflow to electrically connect the part of the welded structure 180 to
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`the electrical connection column 120 adjacent thereto, resulting in a poor effect of
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`improving the problem of lapping between adjacent connection structures caused by a
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`small spacing between the connection structures. By controlling the total volume of the
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`welded structure 180, the stability in the production process can be improved, and the
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`reliability of the semiconductor structure can also be improved.
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`
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`[ 0030] In some embodiments, the semiconductor structure may further includeafirst
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`

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`electroplating seed layer 190 located between the conductive body 121 andthe first
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`diffusion barrier layer 122.
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`[ 0031]
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`In some embodiments, a part of the first electroplating seed layer 190 may be
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`higher than the surface of the conductive body 121, and the top surface of the first
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`electroplating seed layer 190 may be flush with the top surface of thefirst diffusion barrier
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`layer 122. In other embodiments, the top surface of the first electroplating seed layer 190
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`may also be flush with the top surface of the conductive body 121, and the corresponding
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`height of the top surface of the first electroplating seed layer 190 can be selected based on
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`requirements.
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`[ 0032]
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`The material of the first electroplating seed layer 190 may be copper or
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`aluminum, and the material of the first electroplating seed layer 190 may be the same as
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`that of the conductive body 121. By formingthefirst electroplating seed layer 190, it can
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`be facilitated that the formation of the conductive body 121 is guided. Also the adhesion
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`between the conductive body 121 andthe first diffusion barrier layer 122 can be improved
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`by the first electroplating seed layer 190, thereby improvingthe stability of the connection
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`between the conductive body 121 and the first diffusion barrier layer 122. Furthermore,
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`the cavity defects in the conductive body 121 can be reduced by thefirst electroplating
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`seed layer 190, thereby improving the effect of the first diffusion barrier layer 122 in
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`preventing ion diffusion of the conductive body 121.
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`[ 0033]
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`In some embodiments, the ratio of the depth of the first groove 160 to the depth
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`of the second groove 170 in the direction perpendicular to the first face 100 is in a range
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`of 1:1 to 1:10, for example, 1:3, 1:5, 1:8, etc.
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`[ 0034]
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`It will be understood that the ratio of the depth of the first groove 160 to the
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`depth of the second groove 170 can be adjusted based on actual needs. The sum of the
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`depths of the first groove 160 and the second groove 170 should satisfy that the welded
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`structure 180 needs tofill up the first groove 160 and the second groove 170 after bonding
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`the first base 110 to the second base 140. On the premise that the welded structure 180fills
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`up the first groove 160 and the second groove, the deeper the second groove 170 is, the
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`larger the contact area between the electrical connection column 120 and the conductive
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`column 150 is accordingly, and the larger the contact area is, the better the heat dissipation
`
`

`

`effect of the semiconductor structure is. Whenthe ratio of the depth of the first groove 160
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`to the depth of the second groove 170 is less than 1:10, it may occur that the welded
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`structure 180 cannotfill up the entire first 160 and second 170 grooves, resulting in a low
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`stability of the semiconductorstructure.
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`[ 0035]
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`In some embodiments, the welded structure 180 is also located between the
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`electrical connection column 120 and the sidewalls of the second groove 170, and between
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`the conductive column 150 and theelectrical connection column 120.
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`[ 0036]
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`It will be understood that, during bonding the first base 110 to the second base
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`140, the weldedstructure 180 is heated into a molten state. With the bonding of the first
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`base 110 to the second base 140, the welding structure 180 is deformed. Specifically, the
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`welded structure 180 can be divided into a first welded portion 181, a second welded
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`portion 182, a third welded portion 183 and a fourth welded portion 184. The first welded
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`portion 181 fills up the first groove 160. The second welded portion 182 is located between
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`a sidewall of the second groove 170 adjoining the first groove 160 and a sidewall of the
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`electrical connection column 120 facing the first groove 160. The third welded portion 183
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`is located between the bottom surface of the second groove 170 and the electrical
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`comnection column 120 The fourth welded portion 184 is located between a sidewall of the
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`electrical connection column 120 away from the first groove 160 and a sidewall of the
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`second groove 170 away from thefirst groove 160.
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`[ 0037]
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`It is to be noted that, in the embodiments of the disclosure, the welded structure
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`180 is divided into the first welded portion 181, the second welded portion 182, the third
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`welded portion 183 and the fourth welded portion 184, only for the convenience of
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`describing the welded structure 180, and not limiting the welded structure 180. The first
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`welded portion 181, the second welded portion 182, the third welded portion 183, and the
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`fourth welded portion 184 communicate with each other. The first groove 160 and the
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`second groove 170 are filled up by the welded structure 180 to realize the electrical
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`connection betweenthe electrical connection column 120 and the conductive column 150.
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`Moreover, the tightness of the connection betweenthe first base 110 and the second base
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`140 can be improvedby the welded structure 180.
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`[ 0038]
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`In some embodiments, the material of the welded structure 180 includes tin or
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`10
`
`

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`tin-silver alloy or the like.
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`[ 0039]
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`It can be understood thatthe tin or tin-silver alloy has a lower melting point and
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`a higher condensation point, so that the welded structure 180 becomesliquid and changes
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`from liquid to solid at a faster rate during bondingof the first base 110 to the second base
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`140, thereby shortening the time of the entire preparation process of the semiconductor
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`structure. Tin or tin-silver alloy has a better affinity with metal such as copper, so that the
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`weldedstructure 180 is better connected with the electrical connection column 120 and the
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`conductive column 150, and thus the connectionis tighter. Tin or tin-silver alloy also has
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`a good electrical conductivity, which is convenient for electrical signal
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`transmission
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`between the electrical connection column 120 and the conductive column 150. Tin ortin-
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`silver alloy has a goodfluidity after heating, which is also convenient to bondthe electrical
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`connection column 120 to the conductive column 150.
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`[ 0040]
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`In some embodiments, the semiconductorstructure may further include a second
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`diffusion barrier layer 200 located on the bottom surface and the sidewall ofthe first groove
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`160, and also on the bottom surface and the sidewall of the second groove 170, as well as
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`also on the top surface of the conductive column 150 exposedbythe first groove 160 and
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`the side surface of the conductive column 150 exposed by the second groove 170.
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`[ 0041]
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`By providing the second diffusion barrier layer 200, partial ions in the material
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`of the conductive column 150 can be prevented from entering into the first base 110 during
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`ion diffusion, reducing the possibility of contamination of the first base 110, thereby
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`improving the performance of the semiconductor structure. By providing the second
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`diffusion barrier layer 200, the grain boundaries and various defects of a part of the
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`conductive column 150 can befilled, thereby blocking the rapid diffusion path of atoms.
`
`[ 0042]
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`In some embodiments, the second diffusion barrier layer 200 may have the same
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`material as the first diffusion barrier layer 122, such as tantalum,titanium,titanium nitride,
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`or
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`tantalum nitride,
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`thereby reducing the types of materials
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`for producing the
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`semiconductorstructure and thusfacilitating the control of the entire production process.
`
`[ 0043]
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`In some embodiments, the semiconductorstructure may further include a second
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`electroplating seed layer 210, which is located between the second diffusion barrier layer
`
`11
`
`

`

`200 and the bottom surface and sidewall of the first groove 160, and also between the
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`second diffusion barrier layer 200 and the bottom surface and the sidewall of the second
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`groove 170, as well as also between the second diffusion barrier layer 200 and the top
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`surface of the conductive column 150 exposed by the first groove 160, and between the
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`second diffusion barrier layer 200 and the side surface of the conductive column 150
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`exposed by the second groove 170.
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`[ 0044]
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`In some embodiments, by providing the second electroplating seed layer 210,
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`the adhesion between the conductive column 150 and the second diffusion barrier layer
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`200 can be improved, thereby improving the stability of the connection between the
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`conductive column 150 and the second diffusion barrier layer 200. Moreover, the effect of
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`the second diffusion barrier layer 200 in preventing ion diffusion of the conductive column
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`150 can be improved by the laminated structure of the second electroplating seed layer 210
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`and the second diffusion barrier layer 200.
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`[ 0045]
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`In some embodiments, the material of the second electroplating seed layer 210
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`may be the sameasthatof the first electroplating seed layer 190, and the material of the
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`second electroplating seed layer 210 may also be the sameasthat of the conductive column
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`150.
`
`[ 0046]
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`In some embodiments,
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`the semiconductor structure further includes a first
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`protective layer 151 located between the conductive column 150 and the second base 140.
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`The first protective layer 151 facilitates the protection of the conductive column 150. The
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`impact force on the conductive column 150 when the semiconductorstructure is impacted
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`can be reduced bythefirst protective layer 151, thereby protecting the conductive column
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`150.
`
`[ 0047]
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`In some embodiments, the sum of the widths of the first groove 160 and the
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`second groove 170 is 2 to 3 times the width of the conductive column 150, in the direction
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`perpendicular to the extension direction of the conductive column 150. By setting the sum
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`of the widths of the first groove 160 and the second groove 170 to be 2-3 times the width
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`of the conductive column 150, it is advantageousto fill the unoccupied spacein thefirst
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`groove 160 and the second groove 170 by the conductive column 150 and the electrical
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`connection column 120.It will be understood that the ratio of the widthsofthe first groove
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`12
`
`

`

`160 and the second groove 170 to the width of the conductive column 150 can be
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`accordingly adjusted based on the total volume of the conductive column 150 and the
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`electrical connection column 120 to be accommodated in the first groove 160 and the
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`second groove 170.
`
`[ 0048]
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`In the embodiments of the disclosure, the electrical connection columns 120 and
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`the conductive columns 150 can be allowed to cooperate with each other by overlapping
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`the electrical connection columns 120 and the conductive columns 150 in a staggered way,
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`which is beneficial to avoid sliding between the first base 110 and the second base 140,
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`and further improve the bonding stability between the first base 110 and the second base
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`140. By arranging the welded structure 180 in the first groove 160 and the second groove
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`170, the probability of short circuit of the semiconductor structure caused by the electrical
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`connection of adjacent electrical connection columns 120 or adjacent conductive columns
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`150 due to the flow of the welded structures 180 can be reduced. The height of the entire
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`semiconductor structure can be reduced by arranging the part of the electrical connection
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`column 120 higher than the first base 110 in the second groove 170, and the electrical
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`connection column 120 and the conductive column 150 can be overlapped in a staggered
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`way, thereby improving the stability of bonding betweenthe first base 110 and the second
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`base 140. The contact area between the electrical connection column 120 and the
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`conductive column 150 can be increased, by arranging the partof the electrical connection
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`column 120 higher than the first base 110 in the second groove 170 and realizing the
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`electrical connection between the electrical connection column 120 and the conductive
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`column 150 by the welded structure 180, which is beneficial to reduce the contact
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`resistance between the electrical connection column 120 and the conductive column 150
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`and also to improvethe heat dissipation of the semiconductor structure. By arranging the
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`part of the electrical connection columns 120 higherthan the first base 110 in the second
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`groove 170, the probability of short circuit of the semiconductor structure caused by the
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`electrical connection of adjacent electrical connection columns 120 or adjacent conductive
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`columns 150 can also be reduced, thereby improving the performance of the semiconductor
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`structure.
`
`[ 0049]
`
`Correspondingly, an embodimentof the disclosure also provides a method for
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`preparing a semiconductorstructure, which can be used for preparing the semiconductor
`
`13
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`

`

`structure mentioned above. The embodiment described in FIG. | can be referred to for the
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`same or corresponding parts, which will not be described in detail below.
`
`[ 0050]
`
`A semiconductor structure provided by another embodiment of the disclosure
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`will be described in detail below with reference to the accompanying drawings. FIGs. 2 to
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`13 are schematic structural diagrams corresponding to each step of a method for preparing
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`a semiconductorstructure provided by an embodimentof the disclosure.
`
`[ 0051]
`
`Referring to FIGs. 2 to 9, there is provided a first base 110 having a first face
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`100. The first base is provided with an electrical connection column 120 protruding from
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`the first face 100.
`
`[ 0052]
`
`In some embodiments, a method for forming the electrical connection column
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`120 includes the following operations. Thefirst diffusion barrier layer 122 is formed. The
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`conductive body 121 andthe first metal protective layer 123 located on the top surface of
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`the conductive body 121 are formed. The first metal protective layer 123 is also located
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`between the conductive body 121 and the welded structure, and the first diffusion barrier
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`layer 122 is located at least on the side surfaces and the bottom surface of the conductive
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`body 121.
`
`[ 0053]
`
`In some embodiments, the thickness of the first diffusion barrier layer 122 may
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`be from 10nm to 200nm.It is understood that, when the thickness of the first diffusion
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`barrier layer 122 is less than 10nm, the effect of blocking the ion diffusion of the copper
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`metal of the cond