EP0534746A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of fabricating a trench structure in a semiconductor substrate
Assignee: Motorola Solutions Inc
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Filing: 1992-09-24
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Granted: —
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Expires: 2012-09-24
Abstract
Abstract A method of fabricating a trench structure (10) includes providing a substrate (12) having a first layer (16) disposed on a surface thereof and a second layer (18) disposed on the first layer (16). A trench (20) is formed through the first (16) and second (18) layers and into the substrate (12). A dielectric liner (22) is formed on the sidewalls of the trench (20) which is then filled with a trench fill material (24). Portions of the trench liner (22) disposed above the trench fill material (24) are removed and a conformal layer (28) is then formed on the trench structure (10). The conformal layer (28) and a portion of the trench fill material (24) are then oxidized. <IMAGE>
Inventors
- 👤 Syd R. Wilson
- 👤 Yee-Chaung See
- 👤 Han-Bin Kuo Liang
- 👤 Thomas Zirkle
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 22:04
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/61; H10W; H10W10/00; H10W10/01; H10W10/041; H10W10/40; H10W20/00; H10W20/01; H10W20/021
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
145 words
A method of fabricating a trench structure (10) comprising the steps of: providing a substrate (12) having at least a first layer (16) disposed on a surface thereof and a second layer (18) disposed on said first layer (16); forming a trench (20) through said first (16) and second (18) layers and into said substrate (12); forming a dielectric liner (22) in said trench (20), said liner (22) extending above said surface of said substrate (12); forming trench fill material (24) in said trench (20), said trench fill material (24) extending above said surface of said substrate (12); removing portions of said trench liner (22) disposed above said trench fill material (24); forming a conformal layer (28) on said structure (10) including said trench (20) and said second layer (18); and oxidizing said conformal layer (28) and a portion of said trench fill material (24).
Claim 2
Dependent Claim
37 words
The method of claim 1 further including forming an opening (30) in the oxidized conformal (28) and second (18) layers adjacent the trench (20) and forming spacers (36) abutting said second layer (18) in said opening (30).
Claim 3
Dependent Claim
21 words
The method of claim 2 wherein a field oxidation region (38) is formed in the opening (30) above the trench (20).
Claim 4
Dependent Claim
69 words
The method of claim 3 further including the steps of: forming at least one opening (32) in the oxidized conformal (28) and second (18) layers removed from the trench (20); forming spacers (36) abutting said second layer (18) in said at least one opening (32) removed from said trench (20); and forming a field oxidation region (40) in said at least one opening (32) removed from said trench (20).
Claim 5
Dependent Claim
41 words
The method of claim 4 wherein an oxide layer (14) is formed on the substrate (12), the first layer (16) comprises polysilicon, the second layer (18) comprises nitride, the dielectric liner (22) comprises oxide and the trench fill material (24)comprises polysilicon.
Claim 6
Independent Claim
207 words
A method of fabricating a trench structure (10) comprising the steps of: providing a silicon substrate (12) having an oxide layer (14) disposed on a surface thereof, a polysilicon layer (16) disposed on said oxide layer (14) and a nitride layer (18) disposed on said polysilicon layer(16); forming a trench (20) through said nitride (18), polysilicon (16) and oxide (14) layers and into said substrate (12); forming an oxide liner (22) in said trench (20), said liner (22) extending above said surface of said substrate (12); forming polysilicon (24) in said trench (20), said polysilicon (24) extending above said surface of said substrate (12); removing portions of said oxide liner (22) disposed above said polysilicon (24) in said trench (20); forming a conformal polysilicon layer (28) on the surface of the structure (10) including said trench (20) and said nitride layer (18); oxidizing said conformal polysilicon layer (28) and a portion of the polysilicon (24) disposed in said trench (20); forming an opening (30) in said oxidized conformal layer (28) and said nitride layer (18) adjacent said trench (20); forming nitride spacers (36) abutting said nitride layer (18) in said opening (30); and forming a field oxidation region (38) in said opening (30) above said trench (20).
Claim 7
Dependent Claim
70 words
The method of claim 6 further including the steps of: forming at least one opening (32) in the oxidized conformal (28) and nitride (18) layers removed from said trench (20); forming nitride spacers (36) abutting said nitride layer (18) in said at least one opening (32) removed from said trench (20); and forming a field oxidation region (40) in said at least one opening (32) removed from said trench (20).
Claim 8
Dependent Claim
13 words
The method of claim 6 wherein the oxidized conformal layer (28) is planarized.
Claim 9
Dependent Claim
34 words
The method of claim 8 wherein the oxidized conformal layer (28) is planarized by etching with an HF solution or by applying resin or spin-on-glass to the surface of said oxidized conformal layer (28).
Claim 10
Dependent Claim
24 words
The method of claim 7 wherein the forming openings (32) step includes RIE etching and the polysilicon layer (16) serves as an etch stop.
References Cited (Backward Citations)
No citation records indexed.
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