US5811358A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low temperature dry process for stripping photoresist after high dose ion implantation
Assignee: Promos Technologies Inc
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Filing: 1997-01-03
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Granted: 1998-09-22
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Expires: 2017-01-03
Abstract
Abstract A dry process for stripping photoresist from a semiconductor device during the manufacturing process and after high dose ion implantation is describe. The implant-hardened surface of the photoresist is first stripped by oxygen and nitrogen/hydrogen plasma at a lower temperature (<220° C.) to prevent popping problem. The bulk body of the photoresist is then stripped by oxygen and nitrogen/hydrogen plasma at a higher temperature (>220° C.) to provide a faster reaction rate. The semiconductor wafer is cleaned by ammonium hydroxide and hydrogen peroxide to completely remove remaining contaminant and photoresist residuals. The three-step dry process can effectively strip the post implant photoresist so that it ensures the cleanliness of the wafer for the succeeding processes.
Inventors
- 👤 Mao-Sung Tseng
- 👤 Chao Feng-Hsien
- 👤 Nen-Yu Tsai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:01
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/286; H10P50/287
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
136 words
A method of post high dose ion-implantation photoresist stripping in a manufacture of a semiconductor device, said method comprising the steps of: providing semiconductor device structures on a semiconductor substrate; forming a photoresist layer as ion-implantation mask on the semiconductor substrate; performing high dose ion implantation into said semiconductor substrate while hardening a surface of said photoresist mask to form a mask with a hardened surface and a subsurface; first plasma-etching the implant-hardened surface of said photoresist layer, wherein said first plasma-etching includes oxygen and nitrogen/hydrogen plasmas; second plasma-etching the subsurface of said photoresist layer, wherein said second plasma-etching includes oxygen and nitrogen/hydrogen plasmas and takes place at a higher temperature than said first plasma-etching; third plasma-etching any residual oxide on said photoresist layer, wherein said third plasma-etching includes nitrogen/hydrogen plasmas; and cleaning said semiconductor substrate.
Claim 2
Independent Claim
136 words
A method of post high dose ion-implantation photoresist stripping in a manufacture of a semiconductor device, said method comprising the steps of: providing semiconductor device structures on a semiconductor substrate; forming a photoresist layer as ion-implantation mask on the semiconductor substrate; performing high dose ion implantation into said semiconductor substrate while hardening a surface of said photoresist mask to form a mask with a hardened surface and a subsurface; first plasma-etching the implant-hardened surface of said photoresist layer, wherein said first plasma-etching includes oxygen and nitrogen/hydrogen plasmas; second plasma-etching the subsurface of said photoresist layer, wherein said second plasma-etching includes oxygen and nitrogen/hydrogen plasmas and takes place at a higher temperature than said first plasma-etching; third plasma-etching any residual oxide on said photoresist layer, wherein said third plasma-etching includes nitrogen/hydrogen plasmas; and cleaning said semiconductor substrate.
Claim 3
Dependent Claim
18 words
The method of claim 1, wherein said semiconductor device structure comprises a source/drain regions of an integrated circuit.
Claim 4
Dependent Claim
23 words
The method of claim 1, wherein said high dose ion implantation has a dose of 10 15 to 5×10 16 cm -2 .
Claim 5
Dependent Claim
22 words
The method of claim 1, wherein said cleaning uses sulfuric acid and hydrogen peroxide followed by ammonium hydroxide and hydrogen peroxide solvents.
Claim 6
Dependent Claim
13 words
The method of claim 1, wherein said higher temperature is above 220° C.
Claim 7
Dependent Claim
23 words
The method of claim 1, wherein the first plasma-etching takes place at a temperature in the range of from 150° to 200° C.
Claim 8
Dependent Claim
70 words
The method of claim 1, wherein the implant-hardened photoresist surface is removed by oxygen and nitrogen/hydrogen plasma in a low temperature environment and then the temperature is increased to a higher temperature than said first plasma-etching to accelerate stripping of the subsurface of said photoresist while using oxygen and nitrogen/hydrogen plasma and removing any oxide residual still remaining attached to the wafer with a third plasma-etching using nitrogen or hydrogen.
Claim 9
Dependent Claim
15 words
The method of claim 7, wherein the residual oxide is As 2 O 3 .
Claim 10
Dependent Claim
17 words
The method of claim 8, wherein the third step plasma-etch is performed in an oxygen-free plasma environment.
Claim 11
Dependent Claim
17 words
The method of claim 7, wherein the third step plasma-etch is performed in an oxygen-free plasma environment.
References Cited (Backward Citations)
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