US5332683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing semiconductor device having elements isolated by trench
Assignee: Toshiba Corp
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Filing: 1993-02-09
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Granted: 1994-07-26
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Expires: 2013-02-09
Abstract
Abstract This invention relates to a method of manufacturing a semiconductor device having elements isolated by a trench. A trench is formed to surround an element region of a silicon substrate by anisotropic etching. A nonoxide film such as a silicon nitride film is selectively formed on the upper surface of the element region. Thermal oxidation is performed using the nonoxide film as a mask to form an oxide film on the inner face of the trench and the upper surface of a field region. Thereafter, a polysilicon layer is buried in the trench, and after the surface of the polysilicon layer is flattened, a capping oxide film is formed on the upper surface of the trench. In addition, a non-oxide film is formed to have an interval between the end of the nonoxide film and the trench of 2 μm or more.
Inventors
- 👤 Naoto Miyashita
- 👤 Koichi Takahashi
- 👤 Hironori Sonobe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:17
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/61; H10W; H10W10/00; H10W10/01; H10W10/041; H10W10/40
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
172 words
A method of manufacturing a semiconductor device comprising the steps of: anisotropic etching a monocrystalline silicon substrate to form a plurality of trenches therein each having a width of 1 to 2 μm and surrounding each of a plurality of element forming regions wherein a bipolar transistor is formed, said trenches being positioned at intervals of approximately 3 μm; forming a nonoxide film on said element forming regions with an interval between an end portion of said nonoxide film and a side wall of each said trench at a side thereof near said element forming regions of said trenches being approximately 2 μm; forming an oxide film having a film thickness no greater than 9,000 Å on a surface of said substrate including an inside portion of each of said trenches using said nonoxide film as a mask, with each of said trenches not being completely filled by said oxide film; completely filling said trenches with a polysilicon layer having an exposed portion; and oxidizing said exposed portion of said polysilicon layer.
Claim 2
Independent Claim
172 words
A method of manufacturing a semiconductor device comprising the steps of: anisotropic etching a monocrystalline silicon substrate to form a plurality of trenches therein each having a width of 1 to 2 μm and surrounding each of a plurality of element forming regions wherein a bipolar transistor is formed, said trenches being positioned at intervals of approximately 3 μm; forming a nonoxide film on said element forming regions with an interval between an end portion of said nonoxide film and a side wall of each said trench at a side thereof near said element forming regions of said trenches being approximately 2 μm; forming an oxide film having a film thickness no greater than 9,000 Å on a surface of said substrate including an inside portion of each of said trenches using said nonoxide film as a mask, with each of said trenches not being completely filled by said oxide film; completely filling said trenches with a polysilicon layer having an exposed portion; and oxidizing said exposed portion of said polysilicon layer.
Claim 3
Independent Claim
172 words
A method of manufacturing a semiconductor device comprising the steps of: anisotropic etching a monocrystalline silicon substrate to form a plurality of trenches therein each having a width of 0.8 to 1.6 μm and surrounding each of a plurality of element forming regions wherein a bipolar transistor is formed, said trenches being positioned at intervals of approximately 2.4 μm; forming a nonoxide film on said element forming regions with an interval between an end portion of said nonoxide film and a side wall of each said trench at a side thereof near said element forming regions of said trenches being approximately 1.6 μm; forming an oxide film having a film thickness no greater than 7,200 Å on a surface of said substrate including an inside portion of each of said trenches using said nonoxide film as a mask, with each of said trenches not being completely filled by said oxide film; completely filling said trenches with a polysilicon layer having an exposed portion; and oxidizing said exposed portion of said polysilicon layer.
Claim 4
Independent Claim
172 words
A method of manufacturing a semiconductor device comprising the steps of: anisotropic etching a monocrystalline silicon substrate to form a plurality of trenches therein each having a width of 0.8 to 1.6 μm and surrounding each of a plurality of element forming regions wherein a bipolar transistor is formed, said trenches being positioned at intervals of approximately 2.4 μm; forming a nonoxide film on said element forming regions with an interval between an end portion of said nonoxide film and a side wall of each said trench at a side thereof near said element forming regions of said trenches being approximately 1.6 μm; forming an oxide film having a film thickness no greater than 7,200 Å on a surface of said substrate including an inside portion of each of said trenches using said nonoxide film as a mask, with each of said trenches not being completely filled by said oxide film; completely filling said trenches with a polysilicon layer having an exposed portion; and oxidizing said exposed portion of said polysilicon layer.
Claim 5
Independent Claim
172 words
A method of manufacturing a semiconductor device comprising the steps of: anisotropic etching a monocrystalline silicon substrate to form a plurality of trenches therein each having a width of 0.7 to 1.4 μm and surrounding each of a plurality of element forming regions wherein a bipolar transistor is formed, said trenches being positioned at intervals of approximately 2.1 μm; forming a nonoxide film on said element forming regions with an interval between an end portion of said nonoxide film and a side wall of each said trenches at a side thereof near said element forming regions of said trenches being approximately 1.4 μm; forming an oxide film having a film thickness no greater than 6,300 Å on a surface of said substrate including an inside portion of each of said trenches using said nonoxide film as a mask, with each of said trenches not being completely filled by said oxide film; completely filling said trenches with a polysilicon layer having an exposed portion; and oxidizing said exposed portion of said polysilicon layer.
Claim 6
Independent Claim
172 words
A method of manufacturing a semiconductor device comprising the steps of: anisotropic etching a monocrystalline silicon substrate to form a plurality of trenches therein each having a width of 0.7 to 1.4 μm and surrounding each of a plurality of element forming regions wherein a bipolar transistor is formed, said trenches being positioned at intervals of approximately 2.1 μm; forming a nonoxide film on said element forming regions with an interval between an end portion of said nonoxide film and a side wall of each said trenches at a side thereof near said element forming regions of said trenches being approximately 1.4 μm; forming an oxide film having a film thickness no greater than 6,300 Å on a surface of said substrate including an inside portion of each of said trenches using said nonoxide film as a mask, with each of said trenches not being completely filled by said oxide film; completely filling said trenches with a polysilicon layer having an exposed portion; and oxidizing said exposed portion of said polysilicon layer.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-07-25 | 1998-01-24 | 1998-07-26 | $2000.00 | Window Closed / Lapsed |
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