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`EXHIBIT
`DSS-2009
`
`DSS—2 009
`
`EXHIBIT
`
`
`
`
`
`—-'——.
`
`January 1990
`89,.
`'Technicaluesclo'sure BulletinVol. 32 No.
`
`,V, . _, ,
`
`
`
`
`
`METHOD TO INCORPORATE THREE saws OE EATTERN mmmmmgx I'N‘ m0 mom-
`HA-SKING snaps
`
`#453,144
`|’<-D-->%
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`F
`
`;-~.
`
`g
`
`1
`
`% MS /‘ 6
`
`\ "é\f\~l\§i
`1"-
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`
`
`
`Fig.“
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`2
`
`mg.
`
`.§<—.—C~>§
`ffi-Rl“
`:11 BM
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`
`\’\i
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`k—E—a
`HHS—+5
`“F”
`
`Fig.
`
`3
`
`“48*“
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`4
`
`_‘.Wh......'
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`ufiwauhim-aw~huuw-..x...-w-~....-.
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`
`
`layer and just
`(PR)
`By hardening a first image inns. first photoresist
`d’eygloping a
`second image infa thicker sacond PE layer, coincident
`openings in the two PR layers provide a first pattern;
`Oxyggn ion
`Etching is then used to remove portions cf-
`the first layer of photo—
`resist which are unprotected by the second photoresist
`layer,_ thus
`
`glamm l990
`
`218
`
`
`
`I
`EXHIBIT N0. «-
`
`3-13,);-
`M. SEIFE
`
`
`
`
`
`
`
`2112mm) TD mccamxué THREE SETS OF E’A'TTERN mmnmrmx m mo mam;
`HA3XING STEPS
`~ Continued
`
`providing a second pattern. Blankgt axppsing and develpping away all
`of the remaining secbnd phocdresist provides a third pattéfin. Tfihs,
`three patterns are created having an overlay tolerance of a sifigle
`alignment.
`Usefiu; applications
`include creating three different
`thicknesses of mazallized patterna within one
`level of dielectric
`material.
`
`Referring t0 Sig‘ 1. a first photorésist layer 2 is deposited on
`substrate 4. Openings having width A ana‘width.3 axe formed in phatcv
`resist
`2 by exposure to a first mask and development.
`Remaining
`photozesist
`2 is than hafdened, e. 3., by a heat
`treatment. Next,
`phatoresisc E is applied and exposed cm a .sacdnd mask whereugon an
`opening having width C is created by exposure and de"elo?ment..
`A
`pattern defined by caincidence of npenings having width A and C
`(D)
`can then be _etched in subs-trace 4 The pattern hav5.ng width 3 coulé
`be a via hoié in a dielectric substrate 4 for a
`level—to~level
`in—
`tarconuecti-‘Dn.
`
`Referring to 31g. 2, a reactive axygan ion etching process is
`used to remove all af bhozcresist 2 which is not covered by phctore—
`515: 6 while an inconsequential amcunt of photoresist 6
`is also re~
`moved;
`Ihere is than an unpreteccad pattern of substrate 4 having
`wiéth C which can be etched to define a par: of an upper
`level of
`wiring connecting so an interlevel cannector
`in the région having
`width D.
`
`Referring to Fig. 3, all remaining photorcsisz 6 is removed by a
`blanket exposuré and éevelopment,,
`A pattegn comprised af openings
`haVing width.A + C t E and B in photoresist 2 may now be ecdhed into
`substrate 4. Remaining photoresis: is removad to camplece the cross
`section shown in Fig. 3.
`,The pattern having width 3 could be used to
`canstruc: a thin fuse link which can be electrically blown. Ancnher
`application of the pattern having width B is for monitoriag planaria-
`ing processes. Either planarization and point a: planarization uni~
`farmity may be fiatected by appropriate fiesigp of
`the shape of
`the
`region having width B.
`
`Conformal deposition of a cauducter and plauarization cbmplece
`the applications des¢ribed-
`
`219
`
`Vol. 32 No. 8A January 1990
`
`IBM Technical Diaclosure Bulletin
`
`
`
` D
`15 Technicaiuisciosure Butletin Vol. 33 No. 3A August 1.990
`
`
`
`GOPQLEMERTMY SELECTIVE WRITING BY DIRECTuURITE E‘BEAM/OPTICAL LITEO—
`5111331? 931116 MIXED POSI’i‘IVE AND NEGATIVE RESIST
`
`FIG.!
`
`:3 ’
`
`1 [j
`
`:3 wasc‘mm'rs
`i" E EAR
`
`‘
`
`i [:1 0971:». wane
`
`COMPOSITE
`9,1.TTE RN
`
`;
`
`By selectively writing chmpl’ex'fiat‘terns on semicanduccor wafers ULiliZ*
`ing both optical and Babeam technologies‘
`line capacity can be in“
`creased over that which is achievable with direct—urine Ewbeam {£3353}
`considering throughput :astrictiona wihhaut selective writing.
`
`A BREE tool is capable 95 0.25‘ um litbb‘grsph’y, while current
`excimer 1858!.“ lithographic tqols are limited to images larger than 0 5
`pm Fjor
`this reason the DWEB is hrequirgd Ear grincing sub~0 5 wry
`levels. 3.;nce the WEB throughput is gated by pautexn complexity and
`area to be written,
`it: can be increased by w:iting’ only-selects}! pat~
`cams on each water level.
`
`By Splitting the clinical levals into me comglgmenciary patterns.
`the first eons istifig art“ sum—0 Skunicroa images :6 be amused. by 9mm
`and the secnnd {less critical) ca he éxpos'e6_ optically, a comyosice
`paniem can be generated. as shown in Fig. i.
`
`to. be,
`The; precess implementation dependsan the zone: at tasist
`1152.13.30:
`the majority of levels of intern-5:, WEB requires a negativa
`resist and optical tools utilize a positive resisc} Rgferring to 25.9
`2, the first: resist: is coated on the wafer, dptically e’xg'aséd. dévelo'p—
`ed and haraubaked to- prevent: mum: or stacking during sizbseque‘m
`deyosition of a bad-1e: layer.
`(For the aoiysilinon lava}. a barrier
`layer of oxide is used ) Next, a layer of 1000~angscrcm oxide 0: ni~
`
`© IBM Cor9._ $990.
`
`M. SEIFERT
`
`
`
`
`
`
`
`- ‘ ”I.“ .
`
`V.
`
`V
`
`COMPLEHWTARY' sanncnvs Imirmc BY- DLgECILWRITE yum/0min}; LISTED—‘-
`GRAPHY USING. MIXED POSITIVE AND NEGATIVE RESIST — Continued
`
`FIG.2
`
`mu mum,
`ummuwuuu —— mm mm
`Ezs’agg W
`
`POLYSI LICON
`
`'
`
`m __ mu:3 aposuaa
`'
`
`V
`mm...
`g’éxgfi-we RESIST
`—-.______._—.
`“ .Mn'gms
`POLYSILICQN
`
`
`
`NEGATIVE RESIST
`oxen:
`FOSITWE RESIST
`NITRIDE
`Poursmcou
`
`" POS‘TIVE RESIST
`NEGATIVE RESIST
`OXIDE.
`NITRHJE
`POLYSI UCGN
`
`V
`
`*
`
`_
`
`,
`
`smear: m‘rmoz
`, POLYSI'UCOH
`
`ricpe'nding an the; prey-100’s and subseguemg prgcessing,_ is de—
`trige.
`posited. The second resi‘s‘c is applied, DWEB‘ exposed, develbged and the'
`pattern is ét'che'd iritc‘y Elie barrié‘r layer. simult‘a‘héous'ly removing the
`barrier layer from the previously patterned pbsic‘ix'z'e- resist,
`laév’ing‘
`resist pe'de'stalg and barrier layer pedestals. Next,
`chi; nitride is
`etched foliowm by the; stripping oi r'gzsist and Oxide utilizing. nqmal
`processing techniques. If adhesion of the first resist is’ not a pm}:-
`lem while developing the second resist,
`the barrier layer may be omit-—
`ted.
`
`there is an a_d_vantag__e
`Alfhough either exposure can belmadn first,
`t'o' printing».
`the apfiical par—spam tiizst‘- The WEB haS mdrt: accurate
`image placement:
`than this dp‘tical idols ‘and will thferefiore' a’l’igfi to the
`optical exposure more accurately.
`
`63
`
`Vol. 33 No, 3A August 1990
`
`IBM Technical Disclosure Bulletin
`
`
`
`(B 3
`
` (A)
`
`t G 1
`
`q :- fH'TUA (Canto/1:); - (0.35.3314
`b,- Spacina)
`‘- 03 14M
`‘
`'
`a M w‘
`C :: wd’fin
`' D 3
`
`11 ; ‘Fm
`“3133‘ gtéitlw - 2.:
`iiifimsmflfiam m w :x Hts: - y
`Figure 1. Process diagrams provided to explain the pattern forming method of this invention
`
`p
`
`<
`
`Legend:
`
`Substrate
`11
`13 First resist
`
`13a First resist pattern
`13b First resist pattern which has been insolubilized
`
`TSMC-1004 l Page 10 of 11
`
`
`
`It is also satisfactory, of course, to implement this invention so that after formation of the
`
`second resist pattern, it is insolubilized relative to the solvent and developer for a third resist, and
`
`then a third resist pattern is formed, as necessary.
`
`‘
`Effect of the invention
`As is evident from the explanation above, vvith the pattern forming method of this
`invention, a first resist pattern is formed On 'a substrate, and then the next resist pattern can be
`
`formed in' areas in the first resist pattern spaces on the substrate. Thus a minute resist pattern
`
`exceeding the resolution limit of the exposure apparatus (below the resolution limit) can be
`formed.
`
`Therefore, the pattern forming method of this invention makes the manufacture of highly
`integrated SI or the like easy.
`
`Brief description of the figures
`
`Figures 1 (A)-(E) are process diagrams provided to explain the pattern forming method in
`the application example.
`
`11
`
`13
`
`13a
`
`13b
`
`15
`
`15a
`
`17
`
`Substrate
`
`First resist
`
`First resist pattern
`
`First resist pattern which has been insolubilized
`
`Second resist
`
`Second resist pattern
`
`Resist pattern
`
`TSMC-1004 I Page 9 of 11
`
`