EP0304046A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A method of stripping a resist mask
Assignee: Fujitsu Ltd
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Filing: 1988-08-18
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Granted: —
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Expires: 2008-08-18
Abstract
Abstract In a downstream ashing apparatus for removing a used organic resist on a silicon semiconductor wafer, according to the present invention, water vapor is added into an oxygen plasma gas generated by a microwave power. The addition of the water vapor lowers an activation energy of the ashing reaction, and increases reactive species generated in the plasma, accordingly the ashing rate is increased even at as low as 150 DEG C of the wafer temperature. The addition of water vapor increases the ashing rate for a wide range of water content, such as from 5 to 80 %, allowing an easy control of the process. The lowered operating temperature prevents contamination of the semiconductor wafer. Nonuse of CF4 protects the SiO2 layer from being undesirably etched, resulting in prevention of deteriorating the semiconductor characteristics.
Inventors
- 👤 Shuzo Fujimura
- 👤 Keisuke Shinagawa
- 👤 Naomichi Abe
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 12:28
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/286; H10P50/287; G; G03; G03F; G03F7/00; G03F7/26; G03F7/42; G03F7/427
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
80 words
An ashing method for removing a used organic resist from a semiconductor wafer, comprising: generating a gas plasma of an oxygen gas containing water vapor by applying an electromagnetic power to a plasma generating chamber; and introducing reactive species generated in said gas plasma from said plasma generating chamber via holes of a chamber wall toward the semiconductor wafer to react with the used organic resist; said wall and said holes essentially shielding said semiconductor wafer from said electromagnetic power.
Claim 2
Dependent Claim
80 words
An ashing method for removing a used organic resist from a semiconductor wafer, comprising: generating a gas plasma of an oxygen gas containing water vapor by applying an electromagnetic power to a plasma generating chamber; and introducing reactive species generated in said gas plasma from said plasma generating chamber via holes of a chamber wall toward the semiconductor wafer to react with the used organic resist; said wall and said holes essentially shielding said semiconductor wafer from said electromagnetic power.
Claim 3
Dependent Claim
32 words
An ashing method for removing a used organic resist according to claim 1, wherein the contents of said water vapor is more than 1 % of the total gas by flow rate.
Claim 4
Dependent Claim
23 words
An ashing method for removing a used organic resist according to claim 1 or 2, wherein said electromagnetic power is a microwave power.
Claim 5
Dependent Claim
22 words
An ashing method for removing a used organic resist according to claim 3, where said microwave power is of essentially 2,45 MHz.
Claim 6
Dependent Claim
208 words
A plasma ashing apparatus for removing a used organic resist on an semiconductor wafer, comprising: a plasma generation chamber (8) for generating a plasma of a reaction gas including an oxygen gas and a water vapor, said plasma being generated by an excitation of an electromagnetic power applied into said plasma generation chamber; a first gas inlet (31), operatively connected to said plasma generating chamber, for feeding other part of said reaction gas than said water vapor into said plasma generating chamber; a second gas inlet (32), operatively connected to said plasma generating chamber, for feeding said water vapor into said plasma generating chamber; a flow control means (36) for regulating a flow of said water vapor into said plasma generating chamber; a reaction chamber (5) for placing a semiconductor wafer (7) therein, said reaction chamber being separated by a wall (2′) from said plasma generating chamber, said wall having holes (41) on said wall for supplying a reactive species generated in said plasma into said reaction chamber, said holes essentially shield said semiconductor wafer from said electromagnetic power, whereby said reactive species reacts with the used organic resist to be removed; and a gas outlet (51) operatively connected to said reaction chamber for evacuating said reaction chamber.
Claim 7
Dependent Claim
208 words
A plasma ashing apparatus for removing a used organic resist on an semiconductor wafer, comprising: a plasma generation chamber (8) for generating a plasma of a reaction gas including an oxygen gas and a water vapor, said plasma being generated by an excitation of an electromagnetic power applied into said plasma generation chamber; a first gas inlet (31), operatively connected to said plasma generating chamber, for feeding other part of said reaction gas than said water vapor into said plasma generating chamber; a second gas inlet (32), operatively connected to said plasma generating chamber, for feeding said water vapor into said plasma generating chamber; a flow control means (36) for regulating a flow of said water vapor into said plasma generating chamber; a reaction chamber (5) for placing a semiconductor wafer (7) therein, said reaction chamber being separated by a wall (2′) from said plasma generating chamber, said wall having holes (41) on said wall for supplying a reactive species generated in said plasma into said reaction chamber, said holes essentially shield said semiconductor wafer from said electromagnetic power, whereby said reactive species reacts with the used organic resist to be removed; and a gas outlet (51) operatively connected to said reaction chamber for evacuating said reaction chamber.
References Cited (Backward Citations)
No citation records indexed.
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