US4861424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ashing process of a resist layer formed on a substrate under fabrication to a semiconductor device
Assignee: Fujitsu Ltd
•
Filing: 1988-08-19
•
Granted: 1989-08-29
•
Expires: 2008-08-19
Abstract
Abstract A method for removing a resist layer, in which high doses of ions have been implanted, by etching in a first step and a second step performed sequentially. In the first step, a carbonized region produced in the resist layer due to the high dose ion implantation is etched by applying plasma using hydrogen as a reactive gas at a temperature lower than a softening point of the resist layer. In the second step, a lower region, left after firstly etching the upper region, of the resist layer is etched by a conventional method such as a downstream ashing method or a wet stripping method.
Inventors
- 👤 Shuzo Fujimura
- 👤 Junichi Konno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:45
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: 8
Claim 1
Independent Claim
111 words
A method for removing a resist layer formed on a substrate, said resist layer including an ion-implanted region, expanded from an upper surface of the resist layer, in which high doses of ions are implanted, said method comprising the steps of: removing a first region including the ion-implanted region, by a first etching step performed by a plasma discharge process requiring a relatively high amount of power, using hydrogen as a reactive gas, leaving a second region, said first region and said second region forming the resist layer; and removing the second region by a second etching step being performed by a process requiring less power than the plasma discharge process.
Claim 2
Independent Claim
111 words
A method for removing a resist layer formed on a substrate, said resist layer including an ion-implanted region, expanded from an upper surface of the resist layer, in which high doses of ions are implanted, said method comprising the steps of: removing a first region including the ion-implanted region, by a first etching step performed by a plasma discharge process requiring a relatively high amount of power, using hydrogen as a reactive gas, leaving a second region, said first region and said second region forming the resist layer; and removing the second region by a second etching step being performed by a process requiring less power than the plasma discharge process.
Claim 3
Dependent Claim
14 words
A method according to claim 1, wherein said second etching step is downstream etching.
Claim 4
Dependent Claim
16 words
A method according to claim 1, wherein said second etching is by a wet stripping process.
Claim 5
Dependent Claim
25 words
A method according to claim 1, wherein said first etching step is performed at a temperature lower than a softening point of the resist layer.
Claim 6
Dependent Claim
27 words
A method according to claim 1, wherein said step of removing the first region is performed using a mixed gas including said hydrogen and an inert gas.
Claim 7
Dependent Claim
26 words
A method according to claim 1 further comprising a step of annealing the substrate at a temperature higher than 400° C., after removing the resist layer.
Claim 8
Dependent Claim
25 words
A method according to claim 5, wherein said first etching step is performed in a parallel plate plasma etching chamber filled with the mixed gas.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-28 | 1993-02-27 | 1993-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-28 | 1997-02-27 | 1997-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-28 | 2001-02-27 | 2001-08-29 | $7700.00 | Window Closed / Lapsed |