EP0071205A2
Expired / Lapsed
EP
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Method for forming high density dielectric isolation
Assignee: International Business Machines Corp
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Filing: 1982-07-23
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Granted: —
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Expires: 2002-07-23
Abstract
Abstract Deep dielectric isolation zones in a substrate are achieved by forming tenches using reactive ion etching. A glass having a coefficient of thermal expansion closely matching that of the substrate is deposited into the trench to entirely or partially fill the trench. Deposition can be by sedimentation, centrifugation or spin-on techniques. The structure is then fired until the glass particles fuse into a continuous glass layer and final smoothing if necessary can be accomplished.
Inventors
- 👤 Wei-Kan Chu
- 👤 William Aaron Pliskin
- 👤 Jacob Riseman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 09:28
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6921; H10P14/6922; H10P14/63; H10P14/6326; H10P14/6342; H10P14/65; H10P14/6502; H10P14/6506; H10P95/00; H10P95/06; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/014; H10W10/10; H10W10/17; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/951
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
111 words
Method for forming high density dielectric isolation in an integrated circuit structure comprising the steps of: a) forming trenches having substantially vertical sidewalls in a silicon substrate; b) mixing a finely ground glass powder the particles of which having a coefficient of thermal expansion substantially the same as the substrate, with a high dielectric constant fluid, adding a lower dielectric constant fluid and mixing, centrifuging to separate coarse particles from the resulting suspension and, decanting the resulting suspension and, filling the trenches with said suspension; c) firing the structure at a temperature to form a continuous glass layer in the trenches; and d) planarizing the surface of said integrated circuit structure.
Claim 2
Dependent Claim
111 words
Method for forming high density dielectric isolation in an integrated circuit structure comprising the steps of: a) forming trenches having substantially vertical sidewalls in a silicon substrate; b) mixing a finely ground glass powder the particles of which having a coefficient of thermal expansion substantially the same as the substrate, with a high dielectric constant fluid, adding a lower dielectric constant fluid and mixing, centrifuging to separate coarse particles from the resulting suspension and, decanting the resulting suspension and, filling the trenches with said suspension; c) firing the structure at a temperature to form a continuous glass layer in the trenches; and d) planarizing the surface of said integrated circuit structure.
Claim 3
Dependent Claim
29 words
Method of claim 1, wherein the step of forming trenches comprises reactive ion etching trenches in said substrate having sidewalls substantially perpendicular to a top surface of said substrate.
Claim 4
Dependent Claim
28 words
Method of claim 1, wherein the step of filling the trenches comprises sedimenting said suspension into said trenches or sedimenting multiple layers of said suspension into said trenches.
Claim 5
Dependent Claim
20 words
Method of claim 1, wherein the step of filling the trenches comprises centrifugal deposition of said suspension into said trenches.
Claim 6
Dependent Claim
19 words
Method of claim 3, wherein the step of firing comprises firing the structure following each sedimentation of said suspension.
Claim 7
Dependent Claim
46 words
Method of claims 1 and 2, further comprising the steps of depositing a thin oxide film on said substrate prior to forming said trenches, forming said trenches by reactive ion etching and growing a thermal oxide lining for said trenches prior to filling by glass sedimentation.
Claim 8
Dependent Claim
49 words
Method of claim 6, further comprising the steps of depositing a metal film not reactive to either said oxide film or said substrate on top of said oxide film prior to forming said trenches and, lifting off said metal film and any glass deposited thereon to planarize said surface.
Claim 9
Dependent Claim
29 words
Method of claim 7, further comprising the step of applying a thin layer of glass by chemical vapor deposition to smooth and fill the surface of the final structure.
Claim 10
Dependent Claim
16 words
Method of claim 6, wherein the sedimented and fired glass is planarized by reactive ion etching.
Claim 11
Dependent Claim
55 words
Method of claims 1 and 6, further comprising the step of applying a heavier and lower dielectric constant fluid in a sedimenting vessel and underneath said suspension prior to filling and wherein the step of filling results in a void in the bottom of said trenches with a plug of glass formed over said trench.
Claim 12
Dependent Claim
43 words
A deep dieletric isolation zone in a silicon substrate comprising, a trench having substantially vertical sidewalls formed in said substrate and a quantity of glass entirely or partially filling said trench, said glass having a coefficient of thermal expansion matching said silicon substrate.
Claim 13
Dependent Claim
43 words
A deep dieletric isolation zone in a silicon substrate comprising, a trench having substantially vertical sidewalls formed in said substrate and a quantity of glass entirely or partially filling said trench, said glass having a coefficient of thermal expansion matching said silicon substrate.
Claim 14
Dependent Claim
27 words
Dielectric isolation zone of claim 11, wherein said glass fills an upper portion of said trench, sealing an air void in a lower portion of said trench.
Claim 15
Dependent Claim
18 words
Dielectric isolation zone of claims 11 and 12, further comprising a layer of silicon dioxide lining said trench.
Claim 16
Dependent Claim
29 words
Dielectric isolation zone of claim 11, further comprising a layer of SiO 2 lining said trench and an overlayer of Si 3 N 4 covering the Si0 2 layer.
References Cited (Backward Citations)
No citation records indexed.
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