Samsung Electronics Co., Ltd. v. Demaray LLC
`Samsung Electronic's Exhibit 1060
`Exhibit 1060, Page 1
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`

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`IN THE UNITED STATES
`PATENT AND TRADEMARK OFFICE
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`=~PATENT APPLICATION
`Se-Ronald Eugene Miller
`==" John Z.Pastalan
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`“George E. Rittenhouse
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`CASE 1-1-1
`
`TITLE
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`Pulse DC Reactive Sputtering Method
`
`ASSISTANT COMMISSIONER FOR PATENTS
`WASHINGTON,D.C, 20231
`
`SIR:
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`NEW APPLICATION UNDER37 CFR 1.53(b)
`Enclosed are the following papers relating to the above-named application for patent:
`Specification
`4 Informal sheets of drawing(s)
`Information Disclosure Statement
`
`
`
`Basic Fee
`
`
`
`
`Multiple Dependent
`Claim(s), if applicable
`
`Please file the application and charge Lucent Technologies Deposit Account No. 12-2325 the
`amount of $790, to coverthe filing fee. Duplicate copies ofthis letter are enclosed. In the event
`of non-payment or improper payment of a required fee, the Commissioner is authorized to
`charge or to credit Deposit Account No. 12-2325 as required to correct the error.
`
`The Assistant Commissioner for Patents is hereby authorized to treat any concurrentorfuture re-
`ply, requiring a petition for extension of time under 37 CFR § 1.136 forits timely submission, as
`incorporating a petition for extension of time for the appropriate length of time if not submitted
`with the reply.
`
`(Room 3C-512),
`to Docket Administrator
`correspondence
`all
`address
`Please
`Lucent Technologies Inc., 600 Mountain Avenue, P. O. Box 636, Murray Hill, New Jersey
`07974-0636. However, telephone calls should be made to me at 908-582-3246.
`
`Respectfully,
`
`aeJonn M. Harman
`Reg. No. 38173
`Attorney forApplicant(s)
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`Lucent Technologies Inc.
`600 Mountain Avenue
`P. O. Box 636
`Murray Hill, New Jersey 07974-0636
`
`PT 13 12/97
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`Copy provided by USPTO from the IFWImage Database on 09-03-2020
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`Ex. 1060, Page 2
`Ex. 1060, Page 2
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`Miller 1-1-1
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`PULSE DC REACTIVE SPUTTERING METHOD
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`FOR FABRICATING PIEZOELECTRIC RESONATORS
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`Background of the Invention
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`1, Field of the Invention
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`The invention relates to piezoelectric resonators. More particularly, the invention
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`relates to deposition techniques used in fabricating piezoelectric resonators and the
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`piezoelectric resonators made by those deposition techniques.
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`10
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`2. Description of the Related Art
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`Piezoelectric resonators are devices comprising a wafer of piezoelectric material
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`such as quartz, zinc oxide (ZnO), aluminum nitride (AIN) or ceramic material mounted or
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`otherwise formed on a substrate (e.g., silicon or aluminum oxide). Uponthe application
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`15
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`of a voltage to the piezoelectric material, e.g., via electrodes, the piezoelectric material
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`vibrates in a certain vibrational mode depending on the orientation or polarization of the
`piezoelectric material andat a certain (resonant) frequency depending onthe thickness of
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`the piezoelectric material.
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`Piezoelectric resonators provide clearly defined mechanical resonances and are
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`20.
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`useful, e.g., for discriminating between signals based on frequency diversity (i.e., a filter).
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`Also, piezoelectric resonators are useful in providing stable frequency signals, e.g., as a
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`frequencystabilizing feedback elementin an oscillator circuit.
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`Typically, the resonant frequency of the piezoelectric material is inversely
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`proportional to its thickness. Accordingly, for piezoelectric resonators to operate at high
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`frequencies, e.g., frequencies greater than approximately 700 Megahertz (MHz),the
`thickness of the piezoelectric material must be reducedto the point of depositing a thin
`piezoelectric film on the substrate. Conventional deposition techniques for depositing
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`such piezoelectric films include, e.g., chemical vapor deposition (CVD) and sputter
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`deposition such as RF sputter deposition.
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`Ex. 1060, Page 3
`Ex. 1060, Page 3
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`SSEYESee
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`Miller 1-1-1
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`Sputter deposition involves a vacuum deposition process in which a sputtering
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`target is bombarded with ions, typically an ionized noble gas such as argon, and the atoms
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`of the target material are mechanically freed by momentum transfer and available for
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`coating a nearby substrate. Suitable target materials include, e.g., aluminum, silicon and
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`5
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`titanium. In a reactive sputtering process, a reactive gas is introduced into the deposition
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`chamberandreacts with the target material to producea target insulating film that
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`subsequently is sputtered onto the substrate or reacts with freed target material to form a
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`coating material that is sputtered onto the substrate. Suitable reactive gases include
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`oxygen,nitrogen, ammonia and hydrogen.
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`10
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`In DC reactive sputtering, the target material and the reactive gas react in a plasma
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`to produce the coating material. The plasma is formed by the noble gas when an direct
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`current (DC)electric potential is applied within the sputtering chamber. For example,
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`aluminum atoms from an aluminum target react with nitrogen (reactive gas) at the target
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`to produce an insulating film of aluminum nitride (AIN), which is sputtered onto the
`substrate with ions of argon (noble gas). Other suitable coatings include, e.g., oxides
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`15
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`such as aluminum oxide (Al,03), carbides such as silicon carbide (SiC), and nitrides such
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`as titanium nitride (TiN) or zinc oxide (ZnO).
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`However, sputter deposition and reactive sputtering techniques including DC
`reactive sputtering often do not provide adequate deposition rates. Accordingly, such
`techniques take longer to perform, which is undesirable from the standpointof required
`processing time and ultimately is undesirable from an economic standpoint. Also, the
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`20
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`relatively lengthy deposition period increases the introduction of impurities into the
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`piezoelectric film being deposited.
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`Onespecific type of reactive sputtering that often is used in, e.g., silicon
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`25
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`processing methods, is pulse DC reactive sputtering. Since the target insulating film is an
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`insulator(e.g., AIN), the noble gas ions tend to accumulateonits surface, reducing the
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`sputter rate and ultimately terminating the sputter process. In pulse DC reactive
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`sputtering, the electric potential formed between the cathode and the anodein the
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`chamberis reversed periodically to prevent charge accumulation on the target insulating
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`30~—sfilm. More specifically, the positive portion of the applied voltage neutralizes
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`Ex. 1060, Page 4
`Ex. 1060, Page 4
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`Miller 1-1-1
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`accumulation of the noble gas ions on the surface of the target insulating film, and the
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`negative portion of the applied voltage, if sufficient, causes ions from the noble gas to
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`impinge uponthe target insulating film formed on the target material, physically
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`removing ions thereof and allowing them to accumulate on the substrate. This forms the
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`deposited layer or coating.
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`In additionto silicon processing, pulse DC reactive sputtering techniquesalso are
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`useful in depositing,e.g., wear resistant coatings such as tungsten carbide (WC) or
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`titanium nitride (TiN)on,e.g., drill bits, wear plates and valve spindles. See generally,
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`e.g., U.S. Pat. Nos. 5,651,865 and 5,718,813. In pulse DC reactive sputtering, the major
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`qualitative concernsare the ultimate film constituency (i.e., reduced impurities introduced
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`into the deposited film), film stress and film texture. Film texture generally characterizes
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`the physical structure of the film resulting from the shape, arrangementand proportions of
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`its components.
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`With respect to the deposition of thin piezoelectric films such as aluminum nitride
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`15
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`(AIN), an important consideration includesthe crystal orientation of the atoms within the
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`final deposited film. That is, the crystal structure cannot be amorphous; it must be of a
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`single crystal nature. This is because piezoelectricity occurs from the alignmentof the
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`atomic dipoles within the film, and an amorphous film produces random dipole moments
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`with no macroscopic response. Also, it is desired that the film orientation be
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`perpendicular to the substrate to facilitate the launching of longitudinal waves in a
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`structure. It is believed that current deposition techniques are concerned primarily with
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`deposition rates and consideration such as crystal structure are not taken into account.
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`Accordingly, it is desirable to have available an improved technique for
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`depositing thin films of piezoelectric material such as aluminum nitride (AIN) on a
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`substrate that provides piezoelectric films with improved control of film constituency,
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`stress and texture.
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`Su
`
`the Invention
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`The invention is embodied in a pulse DC reactive sputtering method for thin film
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`deposition. The inventive methodis used, e.g., for depositing thin films of piezoelectric
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`Ex. 1060, Page 5
`Ex. 1060, Page 5
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`eeees
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`Miller 1-1-1
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`materials such as aluminum nitride on substrates with patterned electrodes during the
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`fabrication of piezoelectric resonators. Embodiments of the invention includethe steps of
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`providing a target material such as aluminum within the sputtering chamber,positioning a
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`substrate such as silicon within the sputtering chamber, providing a noble gas such as
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`5
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`argon into the sputtering chamber, directing a reactive gas such as nitrogen within the
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`sputtering chamber, applying a pulsed DC voltage across the electrodes within the
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`sputtering chambersufficient to cause ions from the noble gas to impinge upon the thin
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`insulating layer (¢.g., AIN) formed on the target material, physically removing ions
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`thereof and allowing them to accumulate onthe substrate. According to embodiments of
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`10
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`the invention, the pulse width of the positive portion of the applied voltage is adjusted
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`based onits effect on the desired film constituency, stress, and texture. By comparison,
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`conventional arrangements establish pulse widths based on their effect on improving
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`depositionrates, regardless ofits effect on the film texture. Alternatively, embodiments
`of the invention adjust the direction and delivery of the reactive gas within the sputtering
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`+
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`15
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`chamber, e.g., toward the target material, to further enhance the desired film constituency,
`stress, and texture through more efficient reaction by the reactive gas.
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`Brief Description of the Drawings
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`In the drawings:
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`20
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`Figs. la-b are simplified side, cross-sectional views of non-via, Bragg reflection
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`piezoelectric resonators;
`Fig. 2 is a simplified schematic diagram of a pulse DC reactive sputtering ,
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`arrangement;
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`Fig. 3 is a simplified block diagram of a method for fabricating piezoelectric
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`25
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`resonators according to embodiments ofthe invention;
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`Fig. 4a is a graphical diagram of the voltage applied to the electrodes of a pulsed
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`DC reactive sputtering arrangement according to an embodimentofthe invention; and
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`Fig. 4b is a graphical diagram of the voltage applied to the electrodes of a
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`conventional pulsed DC reactive sputtering arrangement.
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`:
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`Ex. 1060, Page 6
`Ex. 1060, Page 6
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`Miller 1-i-1
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`Detailed Description
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`Although specific features, configurations and arrangements are discussed
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`hereinbelow,it should be understood that such is done forillustrative purposes only. A
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`person skilled in the relevant art will recognize that other steps, configurations and
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`arrangements are useful without departing from the spirit and scope of the invention.
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`Embodiments of the invention include piezoelectric resonators with improved
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`piezoelectric film quality and control of methods for making such piezoelectric resonators
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`using pulse DC reactive sputtering for the deposition of thin films of piezoelectric
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`material on substrates. Embodiments of the invention are based on the realization that
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`varying or adjusting the pulse width of the positive portion of the applied DC voltage
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`improves the control and crystallinity of the deposited piezoelectric material.
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`Alternatively, adjusting the direction and delivery of the reactive gas within the sputtering
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`chamberfurther enhances such desired results. Typically, such adjustments are at the
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`expense ofdeposition rate, which drives conventional pulse DC reactive sputtering
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`techniques. However, increased deposition rates, in general, produce metal-rich films
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`that degrade the crystalline structure of the deposited piezoelectric material.
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`Referring now to Fig. la, a simplified diagram of a piezoelectric resonator 100 is
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`shown. The piezoelectric resonator 100 comprises a substrate 110, a layer or body 120 of
`piezoelectric material, and an acoustic reflecting region 125 such as a Braggreflecting
`region therebetween. Alternatively, as shown in Fig. 1b, the layer 120 of piezoelectric
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`material is suspended above the substrate 110 by a suspended membrane 127of,e.g., air
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`or silicon nitride (SiN,). A pair of electrodes 130, 135 are coupled or otherwise attached
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`to piezoelectric material 120 of both arrangements, e.g., by conventional means.
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`The layer 120 of piezoelectric material is made of any suitable material that has
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`piezoelectric qualities sufficient for the particular resonator application. Typical
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`piezoelectric materials include, e.g., quartz, zinc oxide (ZnO), aluminum nitride (AIN)
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`and ceramic materials such as lithium niobate (LiNbO),lithium tantalate (LiTaQ3),
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`paratellurite (TeOQ.) and lead titanate zirconate (PZT-SA). The substrate 110 is madeof,
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`e.g., silicon (Si), aluminum oxide (Al,O3) or other suitable materials such as quartz,
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`
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`MaraljaaTetMaalWaal
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`20
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`sapphire, polysilicon and aerogel.
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`Ex. 1060, Page 7
`Ex. 1060, Page 7
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`Miller 1-1-1
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`In use, the piezoelectric resonator 100 typically has a voltage potential applied
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`across electrode 130, 135, which causes the layer 120 of piezoelectric material to vibrate
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`at a resonant frequency,fo, due to the piezoelectric effect, thus operating as a resonator.
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`The operating frequencyof the piezoelectric resonator 100 depends on the total thickness
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`of the piezoelectric layer 120 and the electrodes 130, 135, which total thickness is due
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`mostly to the thickness of the piezoelectric layer 120. More specifically, the operating
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`frequency is inversely proportional to the thickness of the piezoelectric layer 120 and the
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`electrodes 130, 135. Accordingly, for high operating frequencies,e.g., frequencies
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`greater than approximately 700 Megahertz (MHz), the thickness of the piezoeleciric layer
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`120 has been reducedto the extentthat the piezoelectric layer 120 is merely a thin film
`deposited on the substrate 110. Typical thicknesses of the piezoelectric film range from
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`approximately five hundred (500) nanometers (nm) to approximately ten (10) microns
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`weld
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`(um).
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`Asdiscussed previously herein, conventional sputtering techniques such as sputter
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`deposition, reactive sputter deposition, and DC reactive sputtering do not provide
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`adequate deposition rates. However, one type of conventional sputtering technique that
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`often provides an adequate deposition rate is pulse DC reactive sputtering. Referring now
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`to Fig. 2, a typical pulse DC reactive sputtering arrangement 200 is shown.
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`The conventional arrangement 200 includes a chamber 210 (e.g., a plasma
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`20.
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`chamber) and a pair of electrodes 220, 225 configured within the chamber 210. The
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`electrodes 220, 225 are capable of supplying an electric potential therebetween, as
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`indicated generally by the polarity signs associated therewith. Theelectric potential
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`applied to the electrodes is controlled, e.g., by any suitable control means (shown
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`generally as 230), including pulse width control.
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`25
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`The arrangement 200 includes a first source 240 capable of supplying a noble gas,
`€.g., argon (Ar), into the chamber 210. Other suitable noble gases include, e.g., xenon
`(Xe) and krypton (Kr). Also, the arrangement 200 includes a second source 250 capable
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`of supplying a reactive gas into the chamber 210,e.g., via a gas delivery ring 255. The
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`reactive gas is, €.g., oxygen, nitrogen or other suitable gas.
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`Ex. 1060, Page 8
`Ex. 1060, Page 8
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`Miller 1-1-1
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`A (conductive) target 260 is positioned within the chamber210, e.g., in electrical
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`connection with one of the two electrodes 220. In this manner, the target 260 serves as
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`the cathode during the sputter portion of the cycle when a negative electrical potential is
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`applied across electrodes 220, 225. The target 260 is, e.g., a relatively flat plate of
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`aluminum or other suitable material such as zinc.
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`
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`The substrate 110 upon which the piezoelectric thin film is to be coatedis
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`positioned within the chamber 210, e.g., above the target 260 and the gas delivery ring
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`255. The substrate 110 is made of, e.g., silicon, aluminum oxide (Al,O3) or other suitable
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`material such as quartz, sapphire, polysilicon and aerogel.
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`In operation, the first source 240 provides noble gas into the chamber 210. A
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`second source 250 delivers reactive gas into the sputtering chamber 210. According to
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`embodiments of the invention, the gas delivery ring 255 directs the delivery of the
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`reactive gas at the target 260 (as will be discussed in greater detail hereinbelow). The
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`reactive gas producesa relatively thin insulating film (e.g., AIN) on the target 260. Upon
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`the application of a sufficient electric potential across the electrodes 220, 225, ionization
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`of the noble gas occurs and ions therefrom sputter the thin nitride film on the target 260.
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`Atoms ofthe nitride film onthe target 260 are freed by the ion bombardmentand thus are
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`made available for coating the substrate 110.
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`Pulsed DC reactive sputtering arrangements offer an additional variation to the
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`arrangement described in that the electric potential supplied between the electrodes
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`includes a positive voltage pulse. Conventionally, the voltage is pulsed, e.g., to reduce
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`the possibility of arching (see, e.g., U.S. Patent No. 5,651,865) and to prevent excessive
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`accumulation of noble gas ions on the surface of the target material. However, according
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`to embodiments of the invention, the pulse yields an extra degree of freedom in the film
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`deposition to improvethe film quality and reproducibility.
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`For example, conventional pulse DC reactive sputtering arrangements supply a
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`positive DC voltage of approximately 50 volts typically for approximately 25% ofthe
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`duty cycle and then a negative DC voltage of approximately 200-500 volts for remaining
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`75% of the duty cycle. The duty cycle ratio of positive DC voltage to negative DC
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`30
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`voltage conventional is adjusted based on the effect it has on deposition rate and noble
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`Ex. 1060, Page 9
`Ex. 1060, Page 9
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`Miller 1-1-1
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`gas ion accumulation. As mentioned previously herein, the amplitude and pulse width of
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`the applied DC voltageis controlled, e.g., by any suitable control means (shown generally
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`as 230).
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`However, the conventional desire to neutralize accumulated charge onthe target
`film and maximum deposition rate results in a film thatis slightly metal-rich. This
`stoichiometry producesa relatively poorfilm texture. Therefore, according to
`embodimentsof the invention, the pulse width is adjusted to produce a stoichiometry that
`improves the film texture.
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`In pulse DC reactive sputtering systems, whetherit be in silicon processingor in
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`fabricating piezoelectric resonators, other variables also are managed in an attempt to
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`improve the deposition rate and the overall quality of the deposited films without
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`sacrificing too much from either. Such variables include, e.g., substrate temperature,
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`substrate bias, deposition, gas ratio and chamber pressure. However, just as with the
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`pulse width, many of these variables are advantageous to one aspect and simultaneously
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`are disadvantageous to another aspect. Therefore, many of the variables often are
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`adjusted with such considerations in mind and, accordingly, are set in a manner that
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`amounts to a compromise between the two conflicting aspects. In general, the more
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`important variables are chamberpressure, reactive gas delivery, deposition power and gas
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`ratio.
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`Embodiments of the invention are based on the realization that adjusting the pulse
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`width ofthe positive portion of the applied DC voltage significantly increases the film
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`texture for a given range of other deposition parameters. Furthermore, providing a gas
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`delivery system that directs the reactive gas directly to the active sputter area further
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`enhances the film texture. Accordingly, embodiments of the invention offer piezoelectric
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`resonators having thin films of piezoelectric material with improved texture compared to
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`similarly deposited films without the inventive pulse width adjustments and gas delivery.
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`Fig. 3 shows generally a method 300 for fabricating a piezoelectric resonator
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`according to embodiments of the invention. Reference will be made periodically to the
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`WoWWeWT
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`10
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`15
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`25
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`pulse DC reactive sputtering arrangement 200 shown in Fig. 2 during the discussion
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`30
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`hereinbelow of the method 300. However, it should be remembered that the exemplary
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`Ex. 1060, Page 10
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`Miller 1-1-1
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`MiresanalWWHieWiadMeal
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`IHellA.
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`method 300 shown in Fig. 3 and the pulse DC reactive sputtering arrangement 200 shown
`in Fig. 2 are for illustration purposes only and are not meant to be a limitation of the
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`invention.
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`The first step 310 of the inventive method 300 is to provide the target material
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`260 for use within the sputtering chamber 210 suitable for use in pulse DC reactive
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`sputtering techniques. As discussed previously herein, the target material is, e.g.,
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`aluminum,zinc or other suitable (conductive) material. The next step 320 is to provide or
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`otherwise position the substrate 110 within the sputtering chamber 210. The substrate
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`110 is positioned within the chamber 210, e.g., above the target 260. The substrate is
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`made of, e.g., silicon, aluminum oxide (Al,03) or other suitable material such as quartz,
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`sapphire, polysilicon and aerogel.
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`The next step 330 is to introduce a noble gas (¢.g., via the first source 240) into
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`the sputtering chamber 210. The next step 350 is to introduce the reactive gas into the
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`sputtering chamber 210. According to embodiments ofthe invention, the reactive gas is
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`directed onto the target 260,e.g., by the gas delivery ring 255. The nextstep 340 is to
`apply a sufficient electrical potential across the electrodes 220, 225 to cause ions of the
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`noble to be directed toward the target 260 along with reactive gas with sufficient energy
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`to cause atoms ofthe target material and the insulating layer formed onthe target 260 to
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`be released from the target 260. The next step 360 is to adjust the pulse width to
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`20
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`neutralize the accumulated charge on the surface of the target 260. As discussed
`previously herein, the reactive gas forms a thin film on the surface of the target 260,
`whichis released and, in turn, coats the substrate and forms a layer thereon.
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`As discussed previously herein, pulse DC reactive sputtering arrangements
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`provide a periodic positive DC voltage across the electrodes 220, 225 separated by
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`periods in which a negative voltage potential exists across the electrodes and target
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`sputtering occurs. The application of this periodic positive voltage pulse is done for a
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`numberof reasons, as discussed hereinabove, including to improve film texture and
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`increase piezoelectric response.
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`According to embodiments of the invention, the method 300 includes an adjusting
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`30
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`step 360 to adjust the pulse width of the applied periodic DC pulses for purposes of
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`Ex. 1060, Page 11
`Ex. 1060, Page 11
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`Miller 1-1-1
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`improvingthe crystalline quality of the coating or layer. The pulse width and other
`parameters associated with the applied voltage signal are controlled, e.g., by a control
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`means 230, shown generally in Fig. 2.
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`According to embodiments of the invention,in general, with a given set of
`deposition parameters, adjusting the pulse width and directing the gas components to the
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`active sputtering region on the surface of the target 260 improve the film texture ofthe
`final deposited layer. According to embodiments ofthe invention, the pulse width ofthe
`positive portion of the pulsed DC voltage is adjusted to be within the range from
`approximately 5-40% of the pulsed DC voltage duty cycle.
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`By comparison, conventional pulsed DC reactive sputtering arrangements often
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`establish pulse widths based on increasing or maximizing depositionrates, with little if
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`any regard for the crystalline quality of the deposited layer that ultimately is formed on
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`the substrate. Conventional pulse widths typically are set to no more than approximately
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`25% of the duty cycle and typically remain at or near 25% ofthe duty cycle.
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`Figs. 4a-b illustrate the voltage applied betweenthe electrodes in pulsed DC
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`Teactive sputtering arrangements according to embodiments ofthe invention (Fig. 4a) and
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`according to conventional configurations (Fig. 4b). As shown in Fig, 4a, the applied
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`voltage pulses according to embodiments of the inventiontypically are less than 25% of
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`the duty cycle, which is smailer than the applied voltage pulses in conventional
`arrangements, as shownin Fig. 4b.
`According to embodimentsof the invention, regions of piezoelectric material are
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`formed that have full width at half maximum (FWHM) rocking curves of less than
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`approximately 2.5, but typically within the range from approximately 1.8 to 2.5. By
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`comparison, conventional methods produce piezoelectric materials that have full width at
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`half maximum rocking curvesofat least 2.5, more typically within the range from
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`approximately 3 to 5.
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`wellWETMadatl
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`It will be apparent to those skilled in the art that many changes and substitutions
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`can be made to the embodiments of the piezoelectric resonators deposition techniques
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`herein described without departing from the spirit and scope of the invention as defined
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`30
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`by the appended claims andtheir full scope of equivalents.
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`10
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`Copy provided by USPTO fromthe IFW Image Database on 09-03-2020
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`Ex. 1060, Page 12
`Ex. 1060, Page 12
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`Miller 1-1-1
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`WHATIS CLAIMEDIS:
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`1. A method of pulse DC reactive sputtering, said method comprising the steps
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`of:
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`providing a target material within a sputtering chamber;
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`positioning a substrate within said sputtering chamber;
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`introducing a noble gas into said sputtering chamber;
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`introducing a reactive gas into said sputtering chamber, wherein said reactive gas
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`reacts with a portion of said target material to form an insulating film on said target
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`material;
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`applying a pulsed DC voltage across a pair of electrodes that are positioned within
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`said sputtering chamberin such a way that ions from said noble gas impinge upon the
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`target material and the insulating layer formed on said target material, wherein the freed
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`atoms of the target material and the insulating layer are available for accumulation on said
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`substrate to form a coating thereon; and
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`adjusting the pulse width of said pulsed DC voltage to improve the crystalline
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`structure of the coating formed on said substrate.
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`2. The method as recited in claim 1, wherein the pulsed DC voltage includes a
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`positive portion and a negative portion, and wherein said adjusting step adjusts the
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`positive portion of the pulsed DC voltage to be within the range from approximately 5-
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`40% of the pulsed DC voltage duty cycle.
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`3. The method as recited in claim 1, further comprising the step of directing said
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`reactive gas toward said target material within said sputtering chamber.
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`4. The method as recited in claim 1, wherein the pulsed DC voltage includes a
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`positive portion and a negative portion, and wherein said applying step further comprises
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`10
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`11
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`12
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`13
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`14
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`15
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`tewebo
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`11
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`Copy provided by USPTO from the IFW Image Database on 09-03-2020
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`Ex. 1060, Page 13
`Ex. 1060, Page 13
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`Miller 1-1-1
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`applying the positive portion of the pulsed DC voltage sufficient to limit the
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`accumulation of ions of said noble gas on said target material.
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`5. The method as recited in claim 1, wherein said reactive gas is selected from the
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`group consisting of nitrogen, oxygen, ammonia and hydrogen.
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`6. The methodas recited in claim 1, wherein said target material is selected from
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`the group consisting of aluminum,quartz, zinc oxide (ZnO), aluminum nitride (AIN),
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`lithium niobate (LINDO3), lithium tantalate (LiTaO;), paratellurite (TeO.) and lead
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`titanate zirconate (PZT-SA).
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`7. The methodas recited in claim 1, wherein said noble gas is selected from the
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`group consisting of argon (Ar), xenon (Xe) and krypton (Kr).
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`8. The method as recited in claim 1, wherein said substrate is selected from the
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`group consisting ofsilicon, aluminum oxide (Al,O3), quartz, sapphire, polysilicon and
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`aerogel.
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`9. A method of making a piezoelectric resonator, said method comprising the
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`steps of:
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`providing a sputtering chamber including a target material;
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`positioning a substrate within said sputtering chamber;
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`introducing a noble gas into said sputtering chamber;
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`directing a reactive gas within said sputtering chamber toward the target material,
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`wherein said reactive gas reacts with a portion ofsaid target material to form an
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`insulating film on said target material;
`applying a pulsed DC voltage across a pair of electrodes that are positioned within
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`said sputtering chamber in such a way that ions from said noble gas impinge uponthe
`target material and the insulating layer formed on said target material, wherein the freed
`
`woahLABHlHallUa
`Mial¥TheeMaadEMedEMilth
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`iDveebl
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`12
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`Copy provided by USPTO from the IFW Image Database on 09-03-2020
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`Ex. 1060, Page 14
`Ex. 1060, Page 14
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`SAWIWhetlHeath
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`Hevane
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`AWMMadeWeeAllhalMl
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`Miller 1-1-1
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`atoms of the target material and the insulating layer are available for accumulation on said
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`substrate to form a coating thereon; and
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`adjusting the pulse width of said pulsed DC voltage to improvethe crystalline
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`structure of the coating formed on said substrate.
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`10. The method as recited in claim 9, wherein said adjusting step adjusts the
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`pulse width of the positive portion of the pulsed DC voltage to be within approximately
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`53-40% of the duty cycle.
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`11. The method as recited in claim 9, wherein said target material is selected
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`from the group consisting of aluminum, quartz, zinc oxide (ZnO), aluminum nitride
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`(ANN), lithium niobate (LiNbO), lithium tantalate (LiTaO3), paratellurite (TeO2) and lead
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`titanate zirconate (PZT-SA).
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`12. The method as recited in claim 9, wherein said reactive gas is selected from
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`the group consisting of nitrogen, oxygen, ammonia and hydrogen.
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`13. The method as recited in claim 9, wherein said noble gas is selected from the
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`group consisting of argon (Ar), xenon (Xe) and krypton (Kr).
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`14. The method as recited in claim 9, wherein said substrate is selected from the
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`group consisting ofsilicon, aluminum oxide (Al,O3), quartz, sapphire, polysilicon and
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`aerogel.
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`135. A piezoelectric resonator, comprising:
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`a substrate;
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`aregion of piezoelectric material;
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`an acoustic reflection region operably coupled between said substrate and said
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`region ofpiezoelectric material; and
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`a pair of electrodes coupled to said region of piezoelectric material,
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`nOAF&FWw
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`Copy provided by USPTO from the IFW Image Database on 09-03-2020
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`Ex. 1060, Page 15
`Ex. 1060, Page 15
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`Miller 1-1-1
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`wherein said region of piezoelectric material has a full width at half maximum
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`(FWHM)rocking curve ofless than approximately 2.5.
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`16. The resonatoras recited in claim 15, wherein said region of piezoelectric
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`material has a full width, half maximum rocking curve of within the range from
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`approximately 1.8 to 2.5.
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`17. The resonator as recited in claim 15, wherein said substrate is selected from
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`the group consisting of silicon, aluminum oxide (Al,03), quartz, sapphire, polysilicon and
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`aerogel.
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`18. The resonatoras recited in claim 15, wherein said region of piezoelectric
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`material is selected from the group consisting of aluminum, quartz, zinc oxide (ZnO),
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`aluminum nitride (AIN),lithium niobate (LINbO3), lithium tantalate (LiTaO3),
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`paratellurite