Patent US6499114B1 successfully refreshed from Google Patents.
EP0030116A2
Expired / Lapsed
EP
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Method of manufacturing a semiconductor device having a patterned multi-layer structure
Assignee: Fujitsu Ltd
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Filing: 1980-11-26
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Granted: —
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Expires: 2000-11-26
Abstract
Abstract A layer 13, of poly crystal silicon for example, is etched using a thin photoresist film 15 as a mask. The layer 13 is first etched part way through by isotropic etching, then the remainder of the layer 13 is etched through by anisotropic etching in the direction of thickness of the layer 13. The side walls of a window formed in layer 13 in this way are tapered or inclined so that when an insulation layer 14 and a wiring layer 16 are subsequently formed, there is no danger of shorting of wiring layer 16 to poly crystal silicon layer 13 due to thinning of insulation layer 14 at the edges of the window. The isotropic etching and the anisotropic etching can in many cases be carried out in one and the same dry etching apparatus.
Inventors
- 👤 Kenji Sugishima
- 👤 Tadakazu Takada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 19:44
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/081; H10W20/082; H10P; H10P50/00; H10P50/20; H10P50/24; H10P50/242; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268; H10P50/28; H10P50/282; H10P50/283; H10P50/60; H10P50/66; H10P50/663; H10P50/667; H10P76/00; H10P76/40; H10P76/405; H10P76/408; H10P76/4083; H10W20/031
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
101 words
A method of manufacturing a semiconductor device having a multi-layer structure, in which a first layer is formed to a predetermined pattern over a second layer, which second layer is to be etched and is formed above a semiconductor substrate of the device, and the second layer is etched through using the first layer as a mask, characterised in that the second layer is etched part way through by isotropic etching, and then the reminder of the second layer is etched through by anisotropic etching in the direction of thickness of the second layer, using the first layer as a mask.
Claim 2
Independent Claim
101 words
A method of manufacturing a semiconductor device having a multi-layer structure, in which a first layer is formed to a predetermined pattern over a second layer, which second layer is to be etched and is formed above a semiconductor substrate of the device, and the second layer is etched through using the first layer as a mask, characterised in that the second layer is etched part way through by isotropic etching, and then the reminder of the second layer is etched through by anisotropic etching in the direction of thickness of the second layer, using the first layer as a mask.
Claim 3
Dependent Claim
69 words
A method as claimed in claim 1, wherein the second layer is of a material listed in Tables 1-1 to 2-2 above, the isotropic etching employs an etchant (and etching conditions) indicated as appropriate to that material in any one of Tables 1-1 to 1-4, and the anisotropic etching employs an etchant (and etching conditions) indicated as appropriate to that material in any one of Tables 2-1 and 2-2.
Claim 4
Dependent Claim
30 words
A method as claimed in claim 1, wherein the anisotropic etching is effected by a dry etching being either planar type plasma etching, reactive sputter etching or reactive ion etching.
Claim 5
Dependent Claim
54 words
A method as claimed in claim 3, wherein the isotropic and anisotropic etchings are carried out in one and the same dry etching apparatus, reactive gases employed and/or etching conditions such as amount of gas and gas pressure employed in the apparatus being changed after the isotropic etching to provide for the anisotropic etching.
Claim 6
Dependent Claim
163 words
A method as claimed in claim 4, wherein the second layer is of single crystal silicon or of poly crystal silicon or of Si 3 N 4 , and is first etched part way through by isotropic etching using as reactive gas either CF 4 , or CF 4 + 0 2 , or C 2 F 5 Cl + CF 4 , and is then etched completely through by anisotropic etching using as reactive gas any of CC1 4 , PCl 3 , BC1 3 , SiCl 4 , CF 4 , CF 4 + 0 2 , C 2 F 5 Cl, C 2 F 5 Cl+ CF 4 , or such a chloride compound gas with O 2 or CF 4 , or a mixture of such chloride compound gases, or such a mixture C with O 2 or CF 4 , or SF 6 , O 1 CF 6 in one and the same planar type plasma etching apparatus.
Claim 7
Dependent Claim
109 words
A method as claimed in claim 4, wherein the second layer is of phospho-silicate glass, or Si 3 N 4 or silicon dioxide and is first etched part way through by isotropic etching using as reactive gas C 2 F 5 Cl + CF 4 , or CF 4 or CF 4 + 0 2 , and is then etched completely by anisotropic etching using as reactive gas CF 4 or CF 4 + H 2 , or CHF 3 , or C 2 F 6 , or C 3 F 8 , or C 4 F 8 , in one and the same planar type plasma etching apparatus.
Claim 8
Dependent Claim
100 words
A method as claimed in claim 3, wherein the second layer is of aluminium or aluminium alloy and is first etched part way through by a wet etching process using a solution of H 3 PO 4 as etchant, and then etched completely through by anisotropic etching using as reactive gas either CCl 4 , or PCl 3 , or BC1 3 , or a mixture of these, or such a mixture mixed with 0 2 or CF 4 , or such a mixture mixed with an inactive gas such as A, He in a planar type plasma etching apparatus.
Claim 9
Dependent Claim
40 words
A method as claimed in claim 1, in which the second layer is a composite layer comprising two component layers one over the other, the said one component layer having a higher etching rate than the said other component layer.
Claim 10
Dependent Claim
30 words
A method as claimed in claim 8, wherein the said one component layer is of Si 3 N 4 and the said other component layer is of SiO 2 .
Claim 11
Independent Claim
32 words
A method as claimed in any preceding claim, wherein the first layer is a thin film, for example of photoresist, and the second layer is etchedhalf way through by the isotropic etching.
References Cited (Backward Citations)
No citation records indexed.
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