EP0023146A2
Expired / Lapsed
EP
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Method of manufacturing a semiconductor device wherein first and second layers are formed
Assignee: Fujitsu Ltd
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Filing: 1980-07-21
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Granted: —
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Expires: 2000-07-21
Abstract
Abstract A layer of photoresist 16 having a generally flat surface is formed on a layer of PSG 15 having a projection thereon. A non-selective dry etching process using a reaction gas is effected in which a layer 16 and layer 15 are etched at equal rates. The etching process may be plasma etching using a mixture of a flouride compound gas and oxygen gas. Reactive sputter etching or reactive ion etching can also be used. The photoresist of layer 16 could be replaced by polyimide or liquid glass. PSG layer 15 could alternatively be a layer of polycrystal line silicon or wiring conductor. In each case, the use of a reaction gas mixture which ensures equal etching rates provides a flat surface at the finish of etching.
Inventors
- 👤 Kazuo Tokitomo
- 👤 Ryoji Abe
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 12:45
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/06; H10P95/062; H10P95/064; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268; H10P50/28; H10P50/282; H10P50/283; H10W; H10W10/00; H10W10/01; H10W10/041; H10W10/40; H10W20/00; H10W20/01; H10W20/031; H10W20/062; H10W20/40; H10W20/41; H10W20/435
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
72 words
A method of manufacturing a semiconductor device, whe-rein first and second layers are formed, the second layer on the first, the first layer having projections or indentations and the second layer being such that a generally flat top surface is provided thereby despite the projections and or indentations of the first layer, wherein a non-selective dry etching process is effected wherein the first and second layers are etched at substantially equal rates.
Claim 2
Independent Claim
72 words
A method of manufacturing a semiconductor device, whe-rein first and second layers are formed, the second layer on the first, the first layer having projections or indentations and the second layer being such that a generally flat top surface is provided thereby despite the projections and or indentations of the first layer, wherein a non-selective dry etching process is effected wherein the first and second layers are etched at substantially equal rates.
Claim 3
Dependent Claim
24 words
A method as claimed in claim 1, wherein the non-selective dry etching process involves the use of a gaseous mixture as a reactive gas.
Claim 4
Dependent Claim
46 words
A method as claimed in claim 1 or 2, wherein the said first layer is an interposed insulator layer and is formed on an insulator layer and a wiring conductor layer on a semiconductor substrate, the said first layer being thicker than the wiring conductor layer.
Claim 5
Dependent Claim
34 words
A method as claimed in claim 3, further comprising the step of forming another conductor layer on the flat surface of the first layer left after the first and second layers have been etched.
Claim 6
Independent Claim
21 words
A method as claimed in any preceding claim, wherein the first layer comprises either phospho-silicate glass, silicon dioxide or silicon nitride.
Claim 7
Dependent Claim
37 words
A method as claimed in claim 1 or 2, wherein the said first layer is of polycrystal silicon, and is so formed as to fill a groove in a semiconductor substrate, thereby to provide an isolation region.
Claim 8
Dependent Claim
46 words
A method as claimed in claim 6, comprising a preliminary step in which a silicon nitride layer is formed on the semiconductor substrate prior to formation of the said first layer of polycrystal silicon, and wherein etching is terminated when the silicon nitride layer is exposed.
Claim 9
Independent Claim
60 words
A method as claimed in any preceding claim or wherein the non-selective dry etching process is a plasma etching process in which a gaseous mixture of a flouride compound gas and an oxygen gas is employed, the partial pressures of the gases in the mixture being so selected that the first and second layers are etched at substantially equal rates.
Claim 10
Dependent Claim
27 words
A method as claimed in claim 8, wherein the , flouride compound gas is C 2 F 6 or CF 4 or C 2 F 5 Cl.
Claim 11
Dependent Claim
20 words
A method as claimed in claim 1, 2 or 3, wherein the said first layer is a wiring conductor layer.
Claim 12
Dependent Claim
15 words
A method as claimed in claim 10, wherein the wiring conductor layer is of aluminium.
Claim 13
Dependent Claim
30 words
A method as claimed in claim 10 or 11, read appended to claim 1 or 2, wherein the etching process comprises reactive sputter etching, reactive ion etching or plasma etching.
Claim 14
Dependent Claim
48 words
A method as claimed in claim 12, wherein a reactive gas used in the etching process comprises a gaseous mixture of hydrogen with either carbon tetrachloride (CC1 4 ) or CHC1 3 or CH 2 C1 2 , or comprises a gaseous mixture of CC1 4 and oxygen.
Claim 15
Independent Claim
37 words
A method as claimed in any one of claims 10 to 13, wherein the said first layer is formed on a layer of phosphosilicate glass, or on a layer of SiO 2 deposited by chemical vapour deposition.
Claim 16
Independent Claim
18 words
A method as claimed in any preceding claim, wherein the said second layer is of a resinous material.
Claim 17
Independent Claim
25 words
A method as claimed in any one of claims 1 to 14, wherein the said second layer is of photoresist, or polyimide, or liquid glass.
Claim 18
Independent Claim
23 words
A method as claimed in any one of claims 1 to 14, wherein the second layer is of phospho-silicate glass heated and melted.
References Cited (Backward Citations)
No citation records indexed.
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