TEAM
`./ 5652081,
`~------~~-P-AT-E~N-T------~~~
`NUMBER
`
`CLASS
`
`SUBCLASS
`315
`
`IH!S APPLN 1~ A CON OF
`
`/~
`
`AP~LICATIONS***********~
`
`/
`
`....... ...~~.
`
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`
`priority claimed
`119 conditions met
`
`0
`.D
`
`Verified and Acknowledged
`
`/ r
`Assista,Examiner
`
`~
`KATHLEEN DUDA
`PRIMARY EXAMINER
`GROUP 1100
`
`Sheets Drwg.
`fO
`
`ISSUE
`BATCH
`Examiner NUMBER
`
`Label
`Area
`
`Form PT0-436A
`(Rev. 8/92)
`
`WARNING: The information disclosed herein may be restricted.
`by the United States Code Title 35, Sections 122, 1
`Patent & Trademark Office is·restrict~dto
`
`(FACE)·
`
`SAMSUNG-1002.001
`
`

`
`Ill
`
`Ill co u .0
`::I en
`
`Ill
`Ill co
`0
`
`PATENT DATE
`
`PATENT
`NUMBER
`
`.. SERIAL NUMBER
`
`FILING DA'TE CLASS
`
`SUBCLASS
`j{ 1 ...
`
`GROUP ART UNIT
`~
`1113
`
`EXAMINER
`
`~JAMES M. CLEEVES. REDWOOD CITY, CA.
`j
`::i t
`
`**CONTINUING DATA*********************
`
`\/EniFIED
`[(/1li'=D
`............. ,,.,_, ____ ,,, .................... .
`
`FOREIGN FILING LICENSE GRANTED 03/30/05
`
`0 yes
`no
`Foreign priority claimed
`35 USC 119 conditions met 0 yes
`no
`I~
`
`AS
`
`STATE OR SHEETS
`COUtfTRY DR~GS. CLAIMS
`
`FILING FEE
`INDEP.
`CLAIMS RECEIVED
`
`ATTORNEY'S
`DOCKET NO.
`
`:i. 0'
`
`::?::;:~
`
`PARTS OF APPLICATION
`FILED SEPARATELY
`
`U.S. DEPT. of COMM.-Pat. & TM Office-PT0-436L (rev. 10-78)
`
`Assistant Examiner
`
`Total Claims
`
`Print Fig.
`
`ISSUE
`BATCH
`'"'r"'l'l"''"' Examiner NUMBER
`
`Label
`Area
`
`WARNING: . The information disclosed herein may be restricted. Unauthorized disclosure may be prohibited
`by the United States Code Title 35, Sections 122, 181 and 368. Possession outside the U.S.
`Patent & Trademark Office is restricted to authorized employees and contractors only.
`
`(FACE)
`
`SAMSUNG-1002.002
`
`

`
`......
`
`'
`
`CONTENTS
`
`----papers.
`
`----~'~6·~~~~--------~- -~~~---
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`23.
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`24.
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`25.
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`26.
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`27.
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`28.
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`29.
`
`30.
`
`31.
`
`32.
`
`(FRONT)
`
`SAMSUNG-1002.003
`
`

`
`APPROVED FOR uc~ LJ'
`
`~.
`
`INITIALS - - - - - . . - -
`
`CONTENTS
`
`~----------------- -----~---~
`----------~~~--- -~------~~
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`SAMSUNG-1002.004
`
`

`
`• Staple Issue Slip· Here
`
`CLASSIFIER
`EXAMINER
`.TYPIST
`VERIFIER
`CORPSCORR.
`SPEC. HAND
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`DRAFTING
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`INDEX OF CLAIMS
`
`Date
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`37
`38
`39
`40
`41
`42
`43
`44
`45
`46
`47
`48
`49
`50
`
`1.--61-
`
`Date
`
`-
`
`Claim
`<II
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`51
`52
`53
`54
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`86
`87
`88
`89
`90
`91
`92
`93
`94
`95
`96
`97
`98
`99
`100
`
`SYMBOLS
`../ ................................. Rejected
`= ................................. Allowed
`_ (Tbrough numberal) Canceled
`+ ................................. Restricted
`N ................................. Non-elected
`I ................................. Interference
`A ................................. Appeal
`0 ................................. Objected
`
`(LEFT INSIDE)
`
`SAMSUNG-1002.005
`
`

`
`· Staple Issue Slip ~ .,._
`
`~
`
`/
`
`IDNO.
`
`DATE
`
`V£22
`"'
`
`POSITION/
`CLASSIFIER
`EXAMINER·
`TYPIST
`VERIFIER
`CORPSCORR.
`SPEC. HAND
`FILEMAINT.
`DRAFTING···
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`39
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`42
`43
`44
`45
`46
`47
`48
`49
`50
`
`INDEX OF CLAIMS
`
`Date
`
`.
`
`/
`
`.SYMBOLS
`../ ................................. Rejected
`= ..... , ........................... Allowed
`- (Through numberal) Canceled
`+ ................................. Restricted
`N ............. • ................... Non-i!lected
`I ...........•...... , .............. Interference
`A ................................ Appeal
`0 ................................. Objected
`
`(LEFT INSIDE)
`
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`iil
`c:
`u::
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`86
`87
`88
`89
`90
`91
`92
`93
`94
`95
`96
`97
`98
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`100
`
`SAMSUNG-1002.006
`
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`
`U.S. DEPARTMENT OF COMMEBCE ;
`
`SAMSUNG-1002.007
`
`

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`SAMSUNG-1002.008
`
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`SEARCHED
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`SAMSUNG-1002.009
`
`

`
`PATENT APPLICATION SERIAL NO. OB./361595
`
`U.S. DEPARTMENT OF COMMERCE
`PATENT AND TRADEMARK OFFICE
`FEE RECORD SHEET
`
`040 ~B 01i09/95 08361595
`
`1.
`
`l.O:L
`
`774.00 CK 16820.P048
`
`PT0-1556
`(5/87)
`
`SAMSUNG-1002.010
`
`

`
`BAR CODE LABEL
`
`11111111111111111111111111111111111111111111111111
`
`U.S. PATENT APPLICATION
`
`SERIAL NUMBER
`
`FILING DATE
`
`CL!A"SS
`
`GROUP ART UNIT
`
`08/361,595
`
`12/22/94
`
`1506
`
`JAMES M. CLEEVES, REDWOOD CITY, CA.
`
`1-z
`~ :::;
`
`D..
`D..
`ct
`
`**CONTINUING DATA*********************
`VERIFIED
`
`**FOREIGN/PCT APPLICATIONS************
`VERIFIED
`
`FOREIGN FILING LICENSE GRANTED 03/30/95
`TOTAL
`CLAIMS
`
`INDEPENDENT
`CLAIMS
`
`FILING FEE
`RECEIVED
`
`ATTORNEY DOCKET NO.
`
`STATE OR
`COUNTRY
`
`SHEETS
`DRAWING
`
`· CA
`
`10
`
`22
`
`2
`
`$904.00
`
`16820.P048
`
`BLAKELY SOKOLOFF TAYLOR & ZAFMAN
`12400 WILSHIRE BOULEVARD
`7TH FLOOR
`LOS ANGELES CA 90025
`
`1/)
`
`ffi a: a
`
`a
`ct
`
`METHOD FOR REDUCED PITCH LITHOGRAPHY
`
`w
`
`...J I=
`
`This is to certify that annexed hereto is a true copy from the records of the United Sta\es
`Patent and Trademark Office of the application wh1ch is identified above.
`By authority of the
`COMMISSIONER OF PATENTS AND TRADEMARKS
`
`Date
`
`Certifying Officer
`
`\
`
`I
`
`SAMSUNG-1002.011
`
`

`
`BAR CODE LABEL
`
`llllllllllllllllllllllllllllllllllllllllllllllllll
`
`U.S. PATENT APPLICATION
`
`SERIAL NUMBER
`
`08/361,595
`
`FILING DATE
`
`CLASS
`
`GROUP ART UNIT
`
`12/22/94
`
`430
`
`1113
`
`JAMES M. CLEEVES, REDWOOD CITY, CA.
`
`1-z
`<S
`:::J
`0..
`0..
`<(
`
`**CONTINUING DATA*********************
`VERIFIED
`
`**FOREIGN/PCT APPLICATIONS************
`VERIFIED
`
`FOREIGN FILING LICENSE GRANTED 03/30/95
`TOTAL
`CLAIMS
`
`INDEPENDENT
`CLAIMS
`
`FILING FEE
`RECEIVED
`
`ATTORNEY DOCKET NO.
`
`STATE OR
`COUNTRY
`
`SHEETS
`DRAWING
`
`CA
`
`10
`
`22
`
`2
`
`$904.00
`
`16820.P048
`
`BLAKELY SOKOLOFF TAYLOR & ZAFMAN
`12400 WILSHIRE BOULEVARD
`7TH FLOOR
`LOS ANGELES CA 90025
`
`METHOD FOR REDUCED PITCH LITHOGRAPHY
`
`(/)
`
`(/) w
`a:
`0
`0
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`This is to certify that annexed hereto is a true copy from the records of the United States
`Patent and Trademark Office of the application wh1ch is identified above.
`By authority of the
`COMMISSIONER OF PATENTS AND TRADEMARKS
`
`Date
`
`Certifying Officer
`
`SAMSUNG-1002.012
`
`

`
`06 1361595
`
`,Attorney's Docket No. -.l1!..!06~82~0.!.!!.Pw0>!:48~----
`
`• THE COMMISSIONER OF PATENTS AND TRADEMARKS
`Washington, D.C. 20231
`
`---!..>'--~----,---- sheet(s) of Drawings.
`
`(Title)
`
`_X_
`
`The Filing Fee has been calculated as shown below:
`
`OTHER THANA
`
`For:
`
`Basic Fee:
`
`Total Claims:
`
`+120 $
`
`+240 $
`
`. 1 is less than zero,
`
`enter "0" in Col. 2.
`_X_
`
`{.
`tt•
`
`l ·di.'
`
`'
`4: '
`
`_X_
`
`....
`•.
`
`_x_
`
`TOTAL $
`L - - - - - '
`for the filing fee is enclosed.
`A check for$ 774.00
`A check for$ 40.00
`for recordation of the Assignment is enclosed.
`The Commissioner is hereby authorized to charge payment of the following fees
`associated with this communication, or credit any overpayment, to our Deposit
`Account No. 02-2666. A duplicate copy of this sheet is enclosed.
`_X_ Any additional filing fees required under 37 C.F.R. § 1.16.
`_X_ Any patent application processing fees under 37 C.F.R. § 1.17 .
`The Commissioner is hereby authorized to charge payment of the following fees
`during the pendency of this application, or credit any overpayment, to our
`Deposit Account No. 02-2666. A duplicate copy of this sheet is enclosed.
`_x_ Any processing fees under 37 C.F.R. § 1.17, including any extension
`fees.
`_X_ Any filing fees under 37 C.F.R. § 1.16 for presentation of extra claims.
`Send all correspondence to the undersigned ai!?LAKELY. SOKOLOFF TAYLOR &
`ZAFMAN 12400 Wilshire Boulevard, Seventh Floor,\b.os Angeles. California 90025,
`and direct a telephone calls to the undersigned a 408) 720-8598.
`
`TOTAL $
`
`774
`
`'
`
`Date: December 22, 1994
`
`12400 Wilshire Boulevard
`Seventh Floor
`Los Angeles, California 90025
`(408} 720-8598
`
`Reg. No.:
`
`37 542
`
`(LJV/wes/cak 10/01/94)
`
`"Express Mail" mailing label number TB 855 647 265 US
`
`Date of Deposit December 22. 1994
`
`I hereby certify that this paper or fee is being deposited with the United States Postal Service "Express Mail Post
`Office to Addressee" service under 37 CFR 1.10 on the date indicated above and is addressed to the Commissioner of
`Patents and Trademarks, Washington, D.C. 20231.
`··
`
`SAMSUNG-1002.013
`
`

`
`For:
`
`METHOD FOR REDUCED PITCH LITHOGRAPHY
`
`Enclosed are:
`_X_ ___...,10«------~--- sheet(s) of Drawings.
`- . - An~nrremcrtei~nro ____________________________________ _
`Assignment Cover Sheet Form PT0-1595.
`_X_ A Declaration and Power of Attomey
`unsigned).
`signed/ . X
`A Verified Statement to establish Small Entity Status under 37 C.F.R. §§ 1.9 and 1.27.
`
`,;
`
`(Title)
`
`The Filing Fee has been calculated as shown below:
`
`OTHER THANA
`SMALL ENTITY
`
`Fee
`
`730
`
`44
`
`0
`
`· Multiple Dependent Clairn(s) Presented
`
`+120 $
`
`+240 $
`
`TOTAL $
`
`774
`
`TOTAL $
`
`* If the difference in Col. 1 is less than zero,
`enter "0" in Col. 2.
`_x_ A check for$ 774.00
`for the filing fee is enclosed.
`for recordation of the Assignment is enclosed.
`A check for$ 40.00
`_x_ The Commissioner is hereby·authorized to charge payment of the following fees
`associated with this communication, or credit any overpayment, to our Deposit
`Account No. 02-2666. A duplicate copy of this sheet is enclosed.
`_X_ Any additional filing fees required under 37 C.F.R. § 1.16.
`_X_ Any patent application processing fees under 37 C.F.R. § 1.17.
`_X_ The Commissioner is hereby authorized to charge payment of the following fees
`during the pendency of this application, or credit any overpayment, to our
`Deposit Account No. 02-2666. A duplicate copy of this sheet is enclosed.
`_X_ Any processing fees under 37 C.F.R. § 1.17, including any extension
`fees.
`Any filing fees under 37 C.F.R. § 1.16 for presentation of extra claims.
`X
`_X_ Send all correspondence to the undersigned at BLAKELY, SOKOLOFF, TAYLOR &
`ZAFMAN, 12400 Wilshire Boulevard, Seventh Floor, Los Angeles, California 90025,
`and direct all telephone calls to the undersigned at (408) 720-8598.
`
`Date: December 22. 1994
`
`12400 Wilshire Boulevard
`Seventh Floor
`Los Angeles, California 90025
`{408) 720-8598
`
`"Express Mail" mailing label number TB 855 647 265 US
`
`Date of Deposit
`
`December 22. 1994
`
`(LJV/wes/cak 10/01/94)
`
`I hereby certify that this paper or fee is being deposited with the United States Postal Service "Express Mail Post
`Office to Addressee" service under 37 CFR 1.10 on the date indicated above and is addressed to the-Commissioner of
`Patents and Trademarks, Washington, D.C. 20231.
`
`Christine A. Bybee
`Typed or printed na e o
`.
`r
`
`rs mailing paper or fee)
`'P
`L
`
`SAMSUNG-1002.014
`
`

`
`UNITED STATES PATENT APPLICATION
`
`for
`
`. LMETHOD FOR REDUCED PITCH LITHOGRAPHY
`
`Inventor
`
`James M. Cleeves
`
`I
`
`Prepared by:
`
`BLAKELY, SOKOLOFF, TAYLOR & ZAFMAN
`12400 Wilshire Boulevard
`Seventh Floor
`Los Angeles, California 90025-1026
`
`( 408) 720-8598
`
`Attorney's Docket No. 16820.P048
`
`"Express Mail" mailing label number: TB855647265US
`
`Date of Deposit: ____ ----~.D.!!OecO!.Se;;um"""'b~er'""'22*" • .-!.lz...99:::£4 __ _
`
`I hereby certifY that this paper or j;e is being deposited with
`the United States Postal Service Express Mail Post Office
`to Addressee" service under 37 C.F.R. § 1.1'0 on the date
`indicated above and is addressed to the Commissioner of
`Patents and Trademarks, Washington, D.C. 20231.
`
`SAMSUNG-1002.015
`
`

`
`114 -\D\
`
`ej\
`DB/361595
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`METHOD FOR REDUCED PITCH LITHOGRAPHY
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`BACKGROUND OF THE INVENTION
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`1. Field of the Invention:
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`The present invention relates generally to the field of semiconductor
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`fabrication. More particularly, the present invention relates to the field of
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`lithography processing for semiconductor fabrication.
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`2. Description of the Related Art:
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`Lithography processes are typically used for semiconductor fabrication, for
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`example to form a mask over a layer to be patterned in accordance with various
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`functional and/ or design requirements for fabricating a desired semiconductor
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`device.
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`For a typical lithography process, photoresist is deposited over the layer to be
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`patterned and is exposed to ultraviolet radiation through a mask that defines the
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`pattern to be formed in the photoresist. The photoresist is then developed to form a
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`patterned photoresist layer over the underlying layer to be patterned. Those
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`portions of the underlying layer that are not covered by photoresist may then be
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`etched using suitable etch techniques and chemistries. The pattern in the
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`photoresist is thus replicated in the underlying layer.
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`Typical lithography processes, however, limit the size and density with which
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`semiconductor devices may be fabricated. For example, the minimum resolution
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`capability of the lithography process determines the minimal pitch with ~which
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`features for a patterned layer may be printed. The minimum lithographic
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`resolution for a patterning process may depend, for example, on the lens used in
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`exposing photoresist to radiation through the mask.
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`-1-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.016
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`BRIEF SUMMARY AND OBJECTS OF THE INVENTION
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`One object of the present invention is to provide for a relatively reduced pitch
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`for features of a patterned layer.
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`Another object of the present invention is to provide for the fabrication of
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`relatively denser semiconductor devices.
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`Another object of the present invention is to provide for the fabrication of
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`relatively smaller-sized semiconductor devices.
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`A lithography method for semiconductor fabrication using a semiconductor
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`wafer is described. For the lithography method, a first imaging layer is formed over
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`the semfconductor wafer. The first imaging layer is patterned in accordance with a
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`first pattern to form a first patterned layer. The first patterned layer is stabilized. A
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`second imaging layer is formed over the first patterned layer such that the first
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`patterned layer is surrounded by the second imaging layer. The second imaging
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`layer is patterned in accordance with a second pattern to form a second patterned
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`layer.
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`Another lithography method for semiconductor fabrication using a
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`semiconductor wafer is also described. For the lithography method, an imaging
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`layer is formed over the semiconductor wafer. A portion of the imaging layer is
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`exposed to radiation in accordance with a first pattern. The exposed portion of the
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`imaging layer is stabilized. The imaging layer is patterned in accordance with a
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`second pattern to form a patterned layer.
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`Other objects, features, and advantages of the present invention will be
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`apparent from the accompanying drawings and from the detailed description that
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`follows below.
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`-2-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.017
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`

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`BRIEF DESCRIPTION OF THE DRAWINGS
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`The present invention is illustrated by way of example and not limitation in
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`the figures of the accompanying drawings, in which like references indicate similar
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`elements and in· which:
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`Figure 1 illustrates, in flow diagram form, one lithography method for
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`semiconductor fabrication;
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`Figure 2 illustrates a cross-sectional view of a semiconductor wafer having a
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`first imaging layer being exposed to radiation through a first mask;
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`Figure 3 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 2/after the first imaging layer has been developed;
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`Figure 4 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 3 where a second imaging layer is formed over the wafer and is being exposed
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`to radiation through a second mask;
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`Figure 5 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 4 after the second imaging layer has been developed;
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`Figure 6 illustrates, in flow diagram form, another lithography method for
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`semiconductor fabrication;
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`Figure 7 illustrates a cross-sectional view of a semiconductor wafer having an
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`imaging layer being exposed to radiation through a first mask;
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`Figure 8 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 7 after an exposed portion of the imaging layer has been stabilized;
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`Figure 9 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 8 where the imaging layer is exposed to radiation through a second mask;
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`Figure 10 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 9 after an exposed portion of the imaging layer has been stabilized;
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.018
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`

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`Figure 11 illustrates a cross-sectional view of the ~emiconductor wafer of
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`Figure 10 after the imaging layer has been developed;
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`Figure 12 illustrates, in flow diagram form, another lithography method for
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`semiconductor fabrication;
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`Figure 13 illustrates a cross-sectional view of a semiconductor wafer having
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`an imaging layer being exposed to radiation through a first mask;
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`Figure 14 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 13 after an exposed portion of the imaging layer has been stabilized;
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`Figure 15 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 14 where the imaging layer is exposed to radiation through a second mask;
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`and
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`Figure 16 illustrates a cross-sectional view of the semiconductor wafer of
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`Figure 15 after the imaging layer has been developed.
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`5"
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`-4-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.019
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`

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`DETAILED DESCRIPTION
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`The following detailed description sets forth an embodiment or embodiments
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`in accordance with the present invention for method for reduced pitch lithography.
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`In the following ·description, details are set forth such as specific materials,
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`thicknesses, parameters, etc., in order to provide a thorough understanding of the
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`present invention. It will be evident, however, that the present invention may be
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`practiced without these details. In other instances, well-known process steps,
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`equipment, etc., have not been described in particular detail so as not to obscure the
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`present invention.
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`Figure 1 illustrates, in flow diagram form, one lithography method for
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`semiconductor fabrication. For one embodiment, the method of Figure 1 may be
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`used for semiconductor fabrication using a semiconductor wafer, such as the
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`semiconductor wafer illustrated in Figures 2, 3, 4, and 5 for example.
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`For the method of Figure 1, a semiconductor substrate 200 is provided as
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`illustrated in Figure 2. Substrate 200 may include any suitable semiconductor
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`material, including silicon (Si) for example.
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`As illustrated in Figure 2, a layer 210 may be formed over substrate 200. Layer
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`210 may include any suitable material and may be formed to any suitable thickness
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`using any suitable technique depending, for example, on the purpose of layer 210 in
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`fabricating a desired semiconductor device. Layer 210 may include one or more
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`layers, including device, dielectric, contact, interconnect, and/ or via layers for
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`example. Layer 210 is not necessary to practic~ the method of Figure 1.
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`As one example, layer 210 may include a layer that is to be patterned in
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`accordance with a subsequent mask layer formed over layer 210. Layer 210 may
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`include a dielectric layer, including silicon dioxide (Si02) for example, that is to be
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`-5-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.020
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`

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`patterned for a contact or interconnect layer, for example. Layer 210 may also
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`include a layer over which a via or interconnect layer is to be formed. Layer 210 may
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`have exposed regions to be electrically coupled by vias or interconnects formed in a
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`subsequent layer.
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`For step 100 of Figure 1, a first imaging layer is formed over the
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`semiconductor wafer. As illustrated in Figure 2, an imaging layer 220 is formed
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`over layer 210. Imaging layer 220 may include any suitable material formed to any
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`suitable thickness using any suitable technique.
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`For one embodiment, imaging layer 220 may include a suitable positive
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`photore~ist, for example, that has been spun-on to a thickness of approximately
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`10,000 Angstroms (A). Other suitable thicknesses of positive photoresist, for
`example in the range of approximately 1,000 A to approximately 30,000 A, may also
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`be used. For other embodiments, imaging layer 220 may include a suitable negative
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`photoresist, a suitable radiation-sensitive polyimide, or other suitable radiation-
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`sensitive materials for example. For this detailed description, the term radiation
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`encompasses any energy radiated in the form of waves or particles. The term
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`radiation may include ultraviolet (UV) light, x-ray radiation, electron beam or e(cid:173)
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`beam radiation, vacuum UV radiation, or ion beam radiation for example.
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`For step 110 of Figure 1, the first imaging layer is patterned in accordance with
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`a first pattern to form a first patterned layer. Any suitable lithographic patterning
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`technique may be used and may depend, for example, on the material used for
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`imaging layer 220.
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`Where a positive-tone imaging material is used for imaging layer 220, such as
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`a suitable positive photoresist or a suitable positive-tone radiation-sensitive
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`polyimide for example, imaging layer 220 may be exposed to radiation through a
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`-6-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.021
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`

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`first mask having opaque feature 222 and clear features 221 and 223 as illustrated in
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`Figure 2. The first mask may include any suitable pattern of opaque and clear
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`features that may depend, for example, on the desired pattern to be formed in
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`imaging layer 220. For this detailed description, the term mask encompasses a
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`reticle, for example, for use in a step-and-repeat projection system.
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`Imaging layer 220 may be exposed through the first mask using any suitable
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`form of radiation. The radiation serves to render soluble in a suitable developer
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`that portion of imaging layer 220 exposed to radiation through clear features 221 and
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`223. That portion of imaging layer 220 that has not been exposed to radiation
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`remains/relatively insoluble in the developer.
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`Imaging layer 220 may then be developed in a suitable developer to form a
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`first patterned layer 232. As illustrated in Figure 3, that portion of imaging layer 220
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`exposed to radiation through the first mask is soluble in the developer and is thus
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`dissolved from imaging layer 220. That portion of imaging layer 220 that has not
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`been exposed to radiation is relatively insoluble in the developer, and thus remains
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`to form first patterned layer 232.
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`For other embodiments where a suitable negative-tone imaging material is
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`used for imaging layer 220, the negative-tone imaging layer 220 may be exposed to
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`any suitable form of radiation through a suitable negative-tone mask having opaque
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`features 221 and 223 and a clear feature 222, for example. Negative-tone imaging
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`materials may include a suitable negative photoresist, a suitable positive photoresist
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`that is to be subjected to an image reversal process, or a suitable negative--tone
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`radiation-sensitive polyimide for example. The negative-tone imaging layer 220
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`may be developed in a suitable developer to form a first patterned layer 232 as
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`illustrated in Figure 3. That portion of imaging layer 220 exposed to radiation
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`-7-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.022
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`

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`through the first mask is relatively insoluble in the de~eloper and thus remains to
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`form first patterned layer 232. That portion of imaging layer 220 that has not been
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`exposed to radiation is soluble in the developer and is thus dissolved from imaging
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`layer 220.
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`For step 120 of Figure 1, the first patterned layer is stabilized. Any suitable
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`stabilization technique may be used and may depend, for example, on the material
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`used to form first patterned layer 232.
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`First patterned layer 232 may be stabilized to withstand subsequent
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`lithographic processing steps. First patterned layer 232 may be stabilized to
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`withsta:r;id chemical transformation as a result of any subsequent exposure to
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`radiation, for example. First patterned layer 232 may also be stabilized to withstand
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`dissolution by solvents during a subsequent spin-on of photoresist, for example.
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`First patterned layer 232 may further be stabilized to withstand dissolution by a
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`subsequent developer, for example.
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`Where a positive photoresist is used to form first patterned layer 232, a
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`suitable deep ultraviolet (DUV) stabilization technique may be used to stabilize first
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`patterned layer 232. For one embodiment, first patterned layer 232 may be irradiated
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`with a DUV light source having a wavelength in the range of approximately 200
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`nanometers to approximately 400 nanometers, for example, and simultaneously
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`heated with a temperature ramped up to approximately 230 degrees Celsius, for
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`example, over an approximately 60 second period of time, for example. First
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`patterned layer 232 may be irradiated at that peak temperature for approximately 5
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`seconds, for example. For other embodiments, first patterned layer 232 may be
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`irradiated with a UV light source having other suitable wavelengths, for example in
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`the range of approximately 100 nanometers to approximately 500 nanometers, and
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`-8-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.023
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`may be heated to other suitable peak temperatures, for example in the range of
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`approximately 120 degrees Celsius to approximately 250 degrees Celsius. First
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`patterned layer 232 may be irradiated at a peak temperature for any suitable length of
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`time, for example in the range of approximately 2 seconds to approximately 60
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`seconds.
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`Where first patterned layer 232 includes a positive photoresist, first patterned
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`layer 232 may be stabilized using other suitable techniques. As one example, a prist
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`technique may be used to form a carbon fluorine (CF4) skin over first patterned layer
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`232 by exposing the photoresist to a fluorine ambient. AlilB:+isR technique may also
`be used 1to form a silicon dioxide (Si02) skin over first patterned layer 232. For other
`embodiments, other suitable techniques may be used to form a hardened skin over
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`first patterned layer 232 to stabilize first patterned layer 232. For still other
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`embodiments, the positive photoresist of first patterned layer 232 may be subjected
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`to a suitable heat treatment or to a suitable radiation treatment to stabilize first
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`patterned layer 232.
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`Stabilizing positive photoresist for first patterned layer 232 serves to
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`neutralize photoactive compounds in the photoresist of first patterned layer 232.
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`Upon any subsequent exposure to radiation then, first patterned layer 232 undergoes
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`minimal, if any, chemical transformation. The photoresist of first patterned layer
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`232 may also be subjected to a subsequent spin-on of photoresist with relatively
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`minimal, if any, dissolution by solvents of the subsequent photoresist layer. The
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`photoresist of first patterned layer 232 may further be subjected to a subsequent
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`development with relatively minimal, if any, dissolution by a developer.
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`For other embodiments where a negative photoresist is used to form first
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`patterned layer 232, first patterned layer 232 may be stabilized while first patterned
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`\C!
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`-9-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.024
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`layer 232 is being patterned. Because first patterned lay~r 232 is formed from that
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`portion of negative photoresist that has been exposed to radiation and rendered
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`relatively insoluble in a developer, the negative photoresist of first patterned layer
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`232 is able to withstand chemical transformation from any subsequent exposure to
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`radiation and is able to withstand dissolution by a subsequent developer. The
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`photoresist of first patterned layer 232, however, may be subjected to a suitable
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`stabilization technique as necessary to withstand dissolution by solvents during a
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`subsequent spin-on of photoresist, for example.~UV stabilization
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`technique, a suitable prist technique, a suitabl~s4la:koR technique, a suitable heat
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`treatment, or a suitable radiation treatment, for example, may be used to stabilize
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`the negative photoresist of first patterned layer 232.
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`For still other embodiments where a negative-tone radiation-sensitive
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`polyimide is used to form first patterned layer 232, first patterned layer 232 may be
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`stabilized while first patterned layer 232 is being patterned. Because first patterned
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`layer 232 is formed from that portion of polyimide that has been exposed to
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`radiation and rendered relatively insoluble in a developer, the polyimide of first
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`patterned layer 232 is able to withstand chemical transformation from any
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`subsequent exposure to radiation and is able to withstand dissolution by a
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`subsequent developer. The polyimide of first patterned layer 232, however, may be
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`subjected to a suitable stabilization technique, such as by heat treatment for final
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`curing for example, as necessary to withstand dissolution by the formation of a
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`subsequent layer over first patterned layer 232, for example.
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`For step 130 of Figure 1, a second imaging layer is formed over the
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`semiconductor wafer. As illustrated in Figure 4, an imaging layer 240 is formed
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`over first patterned layer 232 and over layer 210. Imaging layer 240 is formed to
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`\ \
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`-10-
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`Attorney's Docket No. 16820.P048
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`SAMSUNG-1002.025
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`surround first patterned layer 232 on the sidewalls of first patterned layer 232 .
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`Imaging layer 240 may optionally be formed to cover the top of first patterned layer
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`232 as well. Imaging layer 240 may include any suitable material formed to any
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`suitable, thickness using any suitable technique.
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`For one embodiment, imaging layer 240 may include a suitable positive
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