EP0160965A2
Expired / Lapsed
EP
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Method of manufacturing a semiconductor device with a stacked-gate-electrode structure
Assignee: Toshiba Corp
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Filing: 1985-05-07
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Granted: —
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Expires: 2005-05-07
Abstract
Abstract A method of manufacturing a semiconductor device comprising the steps of forming source and drain regions (40, 42) in a semiconductor substrate (10) in a spaced-apart relation, forming a floating gate (26) such that it overlies a channel region between the source and drain regions with a gate insulating film (16) formed between the floating gate and the channel region and forming a control gate (38) such that it overlies a floating gate (26) with an insulating film formed between the control gate and the floating gate. An oxidation-resistant film pattern (22) is formed over a non-monocrystalline silicon layer (18) so as to have a predetermined opening (20). With the oxidation-resistant film pattern (22) as a mask, the non-monocrystalline silicon layer with the opening is selectively oxidized to form a separation insulating film (24) whereby a floating gate is formed with a part of the non-monocrystalline silicon layer insulatingly separated and a floating gate layer portion (28) adjacent to the separation insulating film is smoothly formed.
Inventors
- 👤 Kuniyoshi C/O Patent Division Yoshikawa
- 👤 Masaki C/O Patent Division Sato
- 👤 Seiichi C/O Patent Division Mori
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 09:28
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/68; H10D30/681; H10D64/00; H10D64/01; H10D64/031; H10D64/035; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
159 words
A method of manufacturing a semiconductor device comprising the steps of forming source and drain regions (40, 42) in a semiconductor substrate (10) in a spaced-apart relation, forming a floating gate (26) overlying a channel region between the source and drain regions with a gate insulating film (16) formed between the floating gate and the channel region, and forming a control gate (38) overlying the floating gate with an insulating film formed therebetween, characterized by comprising the steps of: forming an oxidation-resistant film pattern (22) having a predetermined opening (20) over a non-monocrystalline silicon layer (18); and forming a floating gate layer (26) by selectively oxidizing the non-monocrystalline silicon layer (18) within the predetermined opening (20) with the oxidation-resistant film pattern as a mask to form a separation insulating film (24) whereby a portion of the non-monocrystalline silicon layer is insulatingly separated and a floating gate layer portion (28) adjacent to the separation insulating film (24) is smoothly formed.
Claim 2
Independent Claim
159 words
A method of manufacturing a semiconductor device comprising the steps of forming source and drain regions (40, 42) in a semiconductor substrate (10) in a spaced-apart relation, forming a floating gate (26) overlying a channel region between the source and drain regions with a gate insulating film (16) formed between the floating gate and the channel region, and forming a control gate (38) overlying the floating gate with an insulating film formed therebetween, characterized by comprising the steps of: forming an oxidation-resistant film pattern (22) having a predetermined opening (20) over a non-monocrystalline silicon layer (18); and forming a floating gate layer (26) by selectively oxidizing the non-monocrystalline silicon layer (18) within the predetermined opening (20) with the oxidation-resistant film pattern as a mask to form a separation insulating film (24) whereby a portion of the non-monocrystalline silicon layer is insulatingly separated and a floating gate layer portion (28) adjacent to the separation insulating film (24) is smoothly formed.
Claim 3
Dependent Claim
29 words
A method according to claim 1, characterized in that said oxidation-resistant film pattern is so formed that it overlies the non-monocrystalline silicon layer with an insulating film (50) therebetween.
Claim 4
Dependent Claim
29 words
A method according to claim 1 or 2, characterized in that an impurity is heavily doped into the non-monocrystalline silicon layer before the non-monocrystalline silicon layer is selectively oxidized.
Claim 5
Dependent Claim
36 words
A method according to claim 3, characterized in that said impurity is doped with a high concentration level of phosphorus of the order of 3 x 10 20 to 8 x 10 20 / cm 3.
Claim 6
Independent Claim
64 words
A method according to any one of the preceding claims, characterized in that, after the floating gate layer (26) has been formed, a control gate (38) is so formed that it overlies said floating gate layer with the insulating film (50, 22, 52) therebetween, said control gate (38) being made of a metal having a high melting point or a silicide of said metal.
Claim 7
Dependent Claim
47 words
A method according to claim 1, 2, 3 or 4, characterized in that, after the floating gate layer has been formed, a control gate layer (34, 36, 38) made of a polycide is formed such that it overlies the floating gate layer with the insulating film therebetween.
Claim 8
Independent Claim
35 words
A method according to any one of the preceding claims, characterized in that, after said separation insulating film (24) has been formed, a part or a whole of said separation insulating layer (24) is removed.
Claim 9
Dependent Claim
45 words
A method according to claim 1, 2, 3 or 4, characterized in that with said oxidation-resistant pattern (22) left over the floating gate and with said separation insulating film (24) left within the opening, a control gate layer (38) is formed on the resultant structure.
Claim 10
Independent Claim
23 words
A method according to any one of the preceding claims, characterized in that said oxidation-resistant film pattern (22) is a silicon nitride film.
Claim 11
Independent Claim
27 words
A method according to any one of the preceding claims, characterized in that said non-monocrystalline silicon layer is made of a polycrystalline silicon or an amorphous silicon.
References Cited (Backward Citations)
No citation records indexed.
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