Patent US4419142A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4419142A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of forming dielectric isolation of device regions

Assignee: Toshiba Corp
•
Filing: 1981-10-20
•
Granted: 1983-12-06
•
Expires: 2001-10-20
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method of manufacturing a semiconductor device which comprises the steps of: forming on a semiconductor substrate a layer of a material more quickly oxidizable than the semiconductor substrate; selectively oxidizing only that portion of the layer which is mounted on the element region of the semiconductor substrate; removing at least part of said oxidized layer; and wet oxidizing the retained portion of said more oxidizable material layer to provide an element-isolating oxide layer.

Inventors

  • 👤 Naohiro Matsukawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 16:32
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/10; H10W10/13; H10P; H10P95/00; H10W10/01; H10W10/011; H10W10/012; H10W10/0125; H10W10/0126; Y; Y10; Y10S; Y10S148/00; Y10S148/07; Y10S148/106; Y10S148/114; Y10S148/122

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 132 words
A method of manufacturing a semiconductor device which comprises the steps of: (a) depositing on a semiconductor substrate a layer of a material which is oxidized more quickly than said semiconductor substrate; (b) selectively oxidizing that portion of said more quickly oxidizable material layer which is located on the element region of the semiconductor substrate to provide an oxidized layer; (c) removing at least part of said oxidized layer deposited on the element region of the semiconductor substrate; (d) wet oxidizing the retained layer of said more quickly oxidizable material to produce an element-isolating oxide layer with a greater thickness than a remaining oxidized layer on the element region of the semiconductor substrate; and (e) removing the remaining oxidized layer on the element region of the semiconductor substrate to expose said region.
Claim 2
Independent Claim 132 words
A method of manufacturing a semiconductor device which comprises the steps of: (a) depositing on a semiconductor substrate a layer of a material which is oxidized more quickly than said semiconductor substrate; (b) selectively oxidizing that portion of said more quickly oxidizable material layer which is located on the element region of the semiconductor substrate to provide an oxidized layer; (c) removing at least part of said oxidized layer deposited on the element region of the semiconductor substrate; (d) wet oxidizing the retained layer of said more quickly oxidizable material to produce an element-isolating oxide layer with a greater thickness than a remaining oxidized layer on the element region of the semiconductor substrate; and (e) removing the remaining oxidized layer on the element region of the semiconductor substrate to expose said region.
Claim 3
Dependent Claim 33 words
The method according to claim 1, wherein an insulation layer is deposited on the semiconductor substrate and thereafter a layer of a material more quickly oxidizable than said semiconductor substrate is mounted thereon.
Claim 4
Dependent Claim 26 words
The method according to claim 2, wherein the insulation layer is prepared from at least one of a group consisting of silicon oxide and silicon nitride.
Claim 5
Dependent Claim 33 words
The method according to claim 1, wherein a material more quickly oxidizable than the semiconductor substrate is polycrystalline silicon undoped or doped with an impurity, or a silicide of molybdenum, tungsten or tantalum.
Claim 6
Dependent Claim 44 words
The method according to claim 1 or 4, wherein the selectively oxidized layer on the element region of the semiconductor substrate is removed to an extent equal to about three-fourths of the thickness of said oxidized layer, and later the wet oxidation is performed.
Claim 7
Dependent Claim 35 words
The method according to claim 1, 2 or 4, wherein an oxidized layer mounted on the element region of the semiconductor substrate by selective oxidation is wholly removed, and then the wet oxidation is performed.
Claim 8
Dependent Claim 48 words
The method according to claim 1, wherein an oxidized layer is deposited by selective oxidation on the element region of the semiconductor substrate, and an impurity is diffused in the semiconductor substrate by ion implantation with said oxidized layer used as a mask, thereby forming an inversion-preventing layer.
Claim 9
Independent Claim 162 words
A method of manufacturing a semiconductor device which comprises the steps of: (a) forming an insulation layer on a semiconductor substrate; (b) forming on the insulation layer a layer of a material more quickly oxidizable than the semiconductor substrate; (c) selectively oxidizing that portion of said more quickly oxidizable material layer which is located on the element region of the semiconductor substrate to provide an oxidized layer; (d) removing at least part of the oxidized layer mounted on the element region of the semiconductor substrate; (e) wet oxidizing the retained layer of the more quickly oxidizable material in such a manner than an unoxide portion is preserved in the retained layer, thereby producing an element-isolating oxide layer and also forming thereunder a conductive layer, the element-isolating oxide layer being thicker than said oxidized layer remaining on the element region of the semiconductor substrate; and (f) removing an oxidized layer remaining on the element region of the semiconductor substrate to expose said region.
Claim 10
Independent Claim 162 words
A method of manufacturing a semiconductor device which comprises the steps of: (a) forming an insulation layer on a semiconductor substrate; (b) forming on the insulation layer a layer of a material more quickly oxidizable than the semiconductor substrate; (c) selectively oxidizing that portion of said more quickly oxidizable material layer which is located on the element region of the semiconductor substrate to provide an oxidized layer; (d) removing at least part of the oxidized layer mounted on the element region of the semiconductor substrate; (e) wet oxidizing the retained layer of the more quickly oxidizable material in such a manner than an unoxide portion is preserved in the retained layer, thereby producing an element-isolating oxide layer and also forming thereunder a conductive layer, the element-isolating oxide layer being thicker than said oxidized layer remaining on the element region of the semiconductor substrate; and (f) removing an oxidized layer remaining on the element region of the semiconductor substrate to expose said region.
Claim 11
Dependent Claim 24 words
The method according to claim 8, wherein the insulation layer is at least one of a group consisting of silicon oxide and silicon nitride.
Claim 12
Dependent Claim 33 words
The method according to claim 8, wherein the material more quickly oxidizable than the semiconductor substrate is polycrystalline silicon undoped or doped with an impurity, or a silicide of molybdenum, tungsten or tantalum.
Claim 13
Dependent Claim 46 words
The method according to claim 8 or 10, wherein the oxidized layer deposited on the element region of the semiconductor substrate by selective oxidation is removed to an extent equal to about three-fourths of the thickness of said oxidized layer, and the wet oxidation is performed.
Claim 14
Dependent Claim 30 words
The method according to claim 8 or 10, wherein the oxidized layer deposited on the element region of the semiconductor substrate is completely removed, and the wet oxidation is performed.
Claim 15
Dependent Claim 48 words
The method according to claim 8, wherein an oxidized layer is formed on the element region of the semiconductor device by selective oxidation, and an impurity is diffused in the semiconductor substrate by ion implantation with said oxidized layer used as a mask to provide an inversion-preventing layer.

References Cited (Backward Citations)

US3897282A Cited
US3911168A Cited
US4127931A Cited
US4179311A Cited
US4178396A Cited
US4251571A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-12-05 1987-06-06 1987-12-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-12-05 1991-06-06 1991-12-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-12-05 1995-06-06 1995-12-06 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag