Patent US5773346A successfully refreshed from Google Patents.
US5773346A
Expired / Lapsed
US
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Semiconductor processing method of forming a buried contact
Assignee: Aptina Imaging Corp
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Filing: 1995-12-06
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Granted: 1998-06-30
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Expires: 2015-12-06
Abstract
Abstract A semiconductor processing method of forming a buried contact to a substrate region includes, a) providing a stress relief layer over a bulk semiconductor substrate; b) etching the stress relief layer to expose a desired buried contact area of the substrate; c) masking over the stress relief layer and over the desired buried contact area; d) with the masking in place, exposing the substrate to oxidation conditions effective to grow field oxide regions in unmasked areas of the substrate; e) after forming the field oxide regions, removing the masking from the substrate and effectively leaving the buried contact area exposed; f) providing a layer of electrically conductive material over field oxide and exposed buried contact area; and g) patterning the conductive material layer into a conductive line which overlies both field oxide and the buried contact area.
Inventors
- 👤 Monte Manning
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:57
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/021
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
189 words
A semiconductor processing method of making ohmic contact between a transistor gate line and a substrate diffusion region comprising the following steps: providing a stress relief layer over a bulk semiconductor substrate; etching the stress relief layer to expose abulk red first area of the bulk semiconductor substrate; providing an oxidation masking layer over the stress relief layer to cover desired substrate active areas and leave desired substrate field oxide areas exposed, the oxidation masking layer overlying at least a portion of the first area; exposing the substrate to oxidation conditions effective to grow field oxide regions in the unmasked field oxide areas; after field oxide formation, removing the oxidation masking layer from the substrate and effectively leaving the unoxidized first area exposed, the unoxidized first area effectively defining a buried contact opening area to the bulk semiconductor substrate; providing an electrically conductive transistor gate layer over the field oxide regions and buried contact opening area; patterning the gate layer into a transistor gate line which overlies both field oxide and the buried contact area, the patterned gate line being in ohmic electrical communication with the buried contact area.
Claim 2
Dependent Claim
189 words
A semiconductor processing method of making ohmic contact between a transistor gate line and a substrate diffusion region comprising the following steps: providing a stress relief layer over a bulk semiconductor substrate; etching the stress relief layer to expose abulk red first area of the bulk semiconductor substrate; providing an oxidation masking layer over the stress relief layer to cover desired substrate active areas and leave desired substrate field oxide areas exposed, the oxidation masking layer overlying at least a portion of the first area; exposing the substrate to oxidation conditions effective to grow field oxide regions in the unmasked field oxide areas; after field oxide formation, removing the oxidation masking layer from the substrate and effectively leaving the unoxidized first area exposed, the unoxidized first area effectively defining a buried contact opening area to the bulk semiconductor substrate; providing an electrically conductive transistor gate layer over the field oxide regions and buried contact opening area; patterning the gate layer into a transistor gate line which overlies both field oxide and the buried contact area, the patterned gate line being in ohmic electrical communication with the buried contact area.
Claim 3
Dependent Claim
25 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact opening area comprises less than all of the first area.
Claim 4
Dependent Claim
23 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact opening area comprises all of the first area.
Claim 5
Dependent Claim
24 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the oxidation masking layer overlies only a portion of the first area.
Claim 6
Dependent Claim
22 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the oxidation masking layer overlies all of the first area.
Claim 7
Dependent Claim
54 words
The semiconductor processing method of making ohmic contact of claim 1 further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the providing of the conductivity enhancing impurity into the substrate occurring before the step of providing the electrically conductive transistor gate layer.
Claim 8
Dependent Claim
54 words
The semiconductor processing method of making ohmic contact of claim 1 further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the providing of the conductivity enhancing impurity into the substrate occurring after the step of providing the electrically conductive transistor gate layer.
Claim 9
Dependent Claim
73 words
The semiconductor processing method of making ohmic contact of claim 1 further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the electrically conductive gate layer comprises a semiconductive material effectively conductively doped with a conductivity enhancing impurity, the step of providing the conductivity enhancing impurity into the substrate comprising out-diffusion of conductivity enhancing impurity from the gate layer into the substrate.
Claim 10
Dependent Claim
75 words
The semiconductor processing method of making ohmic contact of claim 1 further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the electrically conductive gate layer comprises a semiconductive material effectively conductively doped with a conductivity enhancing impurity, the step of providing the conductivity enhancing impurity into the substrate consisting essentially of out-diffusion of conductivity enhancing impurity from the gate layer into the substrate.
Claim 11
Dependent Claim
27 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact is formed to be self-aligned to an edge of the active area.
Claim 12
Dependent Claim
54 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the oxidation masking layer overlies only a portion of the first area, the step of providing the oxidation masking layer comprising patterning and etching the oxidation masking layer, the etching of the oxidation masking layer comprising etching into the bulk semiconductor substrate.
Claim 13
Dependent Claim
70 words
The semiconductor processing method of making ohmic contact of claim 1 wherein, the oxidation masking layer overlies only a portion of the first area, the step of providing the oxidation masking layer comprising patterning and etching the oxidation masking layer, the etching of the oxidation masking layer comprising etching into the bulk semiconductor substrate; and the buried contact is formed to be self-aligned to an edge of the active area.
Claim 14
Dependent Claim
69 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact opening area comprises less than all of the first area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the providing of the conductivity enhancing impurity into the substrate occurring before the step of providing the electrically conductive transistor gate layer.
Claim 15
Dependent Claim
69 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact opening area comprises less than all of the first area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the providing of the conductivity enhancing impurity into the substrate occurring after the step of providing the electrically conductive transistor gate layer.
Claim 16
Dependent Claim
88 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact opening area comprises less than all of the first area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the electrically conductive gate layer comprises a semiconductive material effectively conductively doped with a conductivity enhancing impurity, the step of providing the conductivity enhancing impurity into the substrate comprising out-diffusion of conductivity enhancing impurity from the gate layer into the substrate.
Claim 17
Dependent Claim
41 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact opening area comprises less than all of the first area; and the buried contact is formed to be self-aligned to an edge of the active area.
Claim 18
Dependent Claim
68 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the oxidation masking layer overlies only a portion of the first area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the providing of the conductivity enhancing impurity into the substrate occurring before the step of providing the electrically conductive transistor gate layer.
Claim 19
Dependent Claim
68 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the oxidation masking layer overlies only a portion of the first area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the providing of the conductivity enhancing impurity into the substrate occurring after the step of providing the electrically conductive transistor gate layer.
Claim 20
Dependent Claim
87 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the oxidation masking layer overlies only a portion of the first area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the electrically conductive gate layer comprises a semiconductive material effectively conductively doped with a conductivity enhancing impurity, the step of providing the conductivity enhancing impurity into the substrate comprising out-diffusion of conductivity enhancing impurity from the gate layer into the substrate.
Claim 21
Dependent Claim
40 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the oxidation masking layer overlies only a portion of the first area; and the buried contact is formed to be self-aligned to an edge of the active area.
Claim 22
Dependent Claim
71 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact is formed to be self-aligned to an edge of the active area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the providing of the conductivity enhancing impurity into the substrate occurring before the step of providing the electrically conductive transistor gate layer.
Claim 23
Dependent Claim
71 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact is formed to be self-aligned to an edge of the active area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the providing of the conductivity enhancing impurity into the substrate occurring after the step of providing the electrically conductive transistor gate layer.
Claim 24
Dependent Claim
90 words
The semiconductor processing method of making ohmic contact of claim 1 wherein the buried contact is formed to be self-aligned to an edge of the active area; and further comprising providing conductivity enhancing impurity into the bulk substrate beneath the buried contact area to define a substrate diffusion region, the electrically conductive gate layer comprises a semiconductive material effectively conductively doped with a conductivity enhancing impurity, the step of providing the conductivity enhancing impurity into the substrate comprising out-diffusion of conductivity enhancing impurity from the gate layer into the substrate.
Claim 25
Dependent Claim
133 words
A semiconductor processing method of forming a buried contact to a substrate region comprising the following steps: providing a stress relief layer over a bulk semiconductor substrate; etching the stress relief layer to expose a desired buried contact area of the substrate; masking over the stress relief layer and over the desired buried contact area; with the masking in place, exposing the substrate to oxidation conditions effective to grow field oxide regions in unmasked areas of the substrate; after forming the field oxide regions, removing the masking from the substrate and effectively leaving the buried contact area exposed; providing a layer of electrically conductive material over field oxide and exposed buried contact area; and patterning the conductive material layer into a conductive line which overlies both field oxide and the buried contact area.
Claim 26
Dependent Claim
133 words
A semiconductor processing method of forming a buried contact to a substrate region comprising the following steps: providing a stress relief layer over a bulk semiconductor substrate; etching the stress relief layer to expose a desired buried contact area of the substrate; masking over the stress relief layer and over the desired buried contact area; with the masking in place, exposing the substrate to oxidation conditions effective to grow field oxide regions in unmasked areas of the substrate; after forming the field oxide regions, removing the masking from the substrate and effectively leaving the buried contact area exposed; providing a layer of electrically conductive material over field oxide and exposed buried contact area; and patterning the conductive material layer into a conductive line which overlies both field oxide and the buried contact area.
Claim 27
Dependent Claim
34 words
The semiconductor processing forming a buried contact of claim 24 wherein the field oxide regions abut substrate active area, the buried contact being formed to be self-aligned to an edge of the active area.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-06-29 | 2001-12-29 | 2002-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-06-29 | 2005-12-29 | 2006-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-06-29 | 2009-12-29 | 2010-06-30 | $7700.00 | Window Closed / Lapsed |