EP0084635A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of forming a wide deep dielectric filled isolation trench in the surface of a silicon semiconductor substrate
Assignee: International Business Machines Corp
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Filing: 1982-12-07
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Granted: —
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Expires: 2002-12-07
Abstract
Abstract A method of forming a wide deep dielectric filled isolation trench in the surface of a silicon semiconductor substrate by forming a wide plug of chemical vapor deposited silicon dioxide in the trench, filling the remaining unfilled trench portions by chemical vapor depositing a layer of silicon dioxide over the substrate and etching back this layer. The method produces chemically pure, planar wide deep dielectric filled isolation trenches and may also be used to simultaneously produce narrow deep dielectric filled isolation trenches.
Inventors
- 👤 Shao-Fu Chu
- 👤 Allen Pang-I Ho
- 👤 Cheng Tzong Horng
- 👤 Bernard Michael Kemlage
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 18:09
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/10; H10W10/17; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P95/00; H10P95/06; H10P95/062; H10P95/064; H10W10/01; H10W10/011; H10W10/014; H10W10/0143
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
121 words
Method of forming a wide deep dielectric filled isolation trench in the surface of a silicon semiconductor substrate comprising the steps of: forming a wide deep trench in the surface of the silicon substrate, and forming a dielectric plug in said trench by chemical vapor depositing a first layer of dielectric material on the surface of the silicon substrate including said trench, removing said first layer of dielectric material from the surface of the silicon substrate and from a narrow portion of said trench using lithography masking and etching techniques, chemical vapor depositing a second layer of dielectric material on the surface of the silicon substrate including said trench, and etching said second layer down to the top of said trench.
Claim 2
Dependent Claim
121 words
Method of forming a wide deep dielectric filled isolation trench in the surface of a silicon semiconductor substrate comprising the steps of: forming a wide deep trench in the surface of the silicon substrate, and forming a dielectric plug in said trench by chemical vapor depositing a first layer of dielectric material on the surface of the silicon substrate including said trench, removing said first layer of dielectric material from the surface of the silicon substrate and from a narrow portion of said trench using lithography masking and etching techniques, chemical vapor depositing a second layer of dielectric material on the surface of the silicon substrate including said trench, and etching said second layer down to the top of said trench.
Claim 3
Dependent Claim
38 words
Method of claim 1 wherein said first layer is of silicon dioxide and of the same thickness in said trench as on the surface of the silicon substrate, the thickness being equal to the depth of said trench.
Claim 4
Dependent Claim
26 words
Method of claims 1 and 2 wherein said first layer is removed by reactive ion etching in an ambient of CF 4 and H 2 .
Claim 5
Dependent Claim
38 words
Method of claims 1 and 2 wherein the chemical vapor deposited first layer of silicon dioxide has a flat surface within said trench and wherein the entire flat surface of said first layer in said trench is masked.
Claim 6
Dependent Claim
36 words
Method of claim 1 wherein the step of forming a wide deep trench is carried out by reactive ion etching, through a suitable mask, in a plasma containing a mixture of SF6, Cl 2 and He.
Claim 7
Dependent Claim
33 words
Method of claims 1 and 2 wherein said first layer and said second layer of silicon dioxide are chemical vapor deposited at 800 °C in an ambient of Silane and N 2 0.
Claim 8
Dependent Claim
36 words
Method of claims 1 and 6 wherein said second layer of silicon dioxide is etched down to the top of said trench by reactive ion etching in an ambient of CF 4 and H 2 .
Claim 9
Dependent Claim
44 words
Method of claims 1 and 5 wherein the step of forming a wide deep trench in the surface of the silicon substrate is followed by the steps of thermally growing a thin layer of silicon dioxide on the walls and floor of said trench.
Claim 10
Dependent Claim
49 words
Method of claim 1 wherein the second chemical vapor depositing step is followed by the step of depositing a layer of photoresist on said second layer and wherein the final etching step includes etching the layer of photoresist and said second layer down to the top of said trench.
Claim 11
Dependent Claim
29 words
Method of one or several of claims 1 to 9 wherein narrow and wide deep dielectric filled isolation trenches are formed in the surface of a silicon semiconductor substrate.
References Cited (Backward Citations)
No citation records indexed.
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