EP0034508A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Self-aligned buried contact and method of making
Assignee: CTU of Delaware Inc
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Filing: 1981-02-23
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Granted: —
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Expires: 2001-02-23
Abstract
Abstract n active region is surrounded by channel stop regions 18) covered with thick oxide (20). Initially the active region is masked by a nitride layer over a thermally-grown oxide layer. Nindows (22) are formed in the mask by conventional methods to separate a channel region under portion 24 of the masking layer from contact regions under portion 26. The substrate (10) of one conductivity type is doped through the windows (22) with material of a second conductivity type. rhick oxide portions are now formed over the doped regions and the masking layers are thereafter removed. A thin oxide ayer is grown over the channel region. Conductors, preferably of poly-crystalline silicon are formed over the channel and contact regions. The contact region of the substrate is then doped with a material of the second conductivity type, preferably through the polycrystalline silicon layer.
Inventors
- 👤 Tsiu C. Chan
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 06:49
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/13; H10D62/149; H10D62/151; H10B; H10B12/00; H10B12/30; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/0125; H10W10/0126; H10W10/10; H10W10/13; H10W20/00; H10W20/01; H10W20/021
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
124 words
A method for making a self-aligned buried contact in an MOS semiconductor device comprising: I (a) depositing a silicon nitride layer on a substrate of a first conductivity, (b) patterning said silicon nitride layer to define a channel region and a contact region spaced from said channel region by a third region, (e) doping the surface of said substrate in said third region with a dopant of a second conductivity, (d) growing thick oxide over said third region, (e) removing said silicon nitride layer from said channel and contact region, (f) forming a thin oxide layer on said channel region, and (g) in either order, doping said contact region with a dopant of said second conductivity, and depositing a conductor over said contact region.
Claim 2
Independent Claim
124 words
A method for making a self-aligned buried contact in an MOS semiconductor device comprising: I (a) depositing a silicon nitride layer on a substrate of a first conductivity, (b) patterning said silicon nitride layer to define a channel region and a contact region spaced from said channel region by a third region, (e) doping the surface of said substrate in said third region with a dopant of a second conductivity, (d) growing thick oxide over said third region, (e) removing said silicon nitride layer from said channel and contact region, (f) forming a thin oxide layer on said channel region, and (g) in either order, doping said contact region with a dopant of said second conductivity, and depositing a conductor over said contact region.
Claim 3
Dependent Claim
28 words
A method according to Claim 1 wherein in step (g); said conductor comprises polycrystalline silicon and said doping of said contact regions occurs after depositing of said conductor.
Claim 4
Dependent Claim
19 words
A method according to Claim 2 wherein said doping comprises the diffusion of a dopant in said contact region.
Claim 5
Dependent Claim
19 words
A method according to Claim 1 wherein in step (c) said doping comprises the ion implantation of a dopant.
Claim 6
Dependent Claim
30 words
A method according to Claim 1 further including: prior to step (a) forming a thin oxide layer on said substrate wherein step (b) includes patterning of said thin oxide layer.
Claim 7
Dependent Claim
31 words
A method according to Claim 5 wherein said thin oxide layer is formed on said channel region by in step (e) removing only said silicon nitride layer from said channel region.
Claim 8
Dependent Claim
21 words
A method according to Claim 5 wherein step (e) includes removing of said thin oxide layer formed prior to step (a).
Claim 9
Dependent Claim
54 words
A self-aligned contact semiconductor structure comprising: .(a) a semiconductor substrate of a first conductivity ( b ) a contact area of a second conductivity on a surface of said substrate, (c) doped regions on each side of said contact area, (d) thick oxide over said doped regions, (e) conductive metallization over said contact area..
Claim 10
Dependent Claim
54 words
A self-aligned contact semiconductor structure comprising: .(a) a semiconductor substrate of a first conductivity ( b ) a contact area of a second conductivity on a surface of said substrate, (c) doped regions on each side of said contact area, (d) thick oxide over said doped regions, (e) conductive metallization over said contact area..
Claim 11
Dependent Claim
15 words
A structure according to Claim 8 wherein said doped areas are of a second conductivity.
Claim 12
Dependent Claim
31 words
A structure according to Claim 8 wherein a least one of said doped regions is of said first conductivity and the remaining of said doped regions are of a second conductivity.
Claim 13
Dependent Claim
20 words
A structure according to Claim 8 wherein said conductive metalization also overlaps at least a portion of said thick oxide.
Claim 14
Dependent Claim
18 words
A structure according to Claim 8 wherein said conductive metalization comprises polycrystalline silicon of a second conductivity type.
References Cited (Backward Citations)
US4187602A
Cited
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