US4845053A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flame ashing process for stripping photoresist
Assignee: Individual
•
Filing: 1988-01-25
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Granted: 1989-07-04
•
Expires: 2008-01-25
Abstract
Abstract Process and apparatus employing flame ashing for stripping photoresist from a substrate in the manufacture of a semiconductor device. The substrate is exposed to the flame with the photoresist to be removed being contacted directly by the flame to oxidize, or ash, the photoresist. The flame is produced by burning oxygen and a gaseous fuel, and the rate of ashing is increased by preheating the substrate. Nitrogen, a nitrogen-containing gas or an inert gas is added to the fuel to provide a cooler flame and an improved ashing rate. In one disclosed embodiment, the oxygen and the gaseous fuel are discharged through a plurality of spaced apart openings in a burner and the substrate is moved relative to the frames to successively ash different portions of the photoresist.
Inventors
- 👤 John Zajac
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:39
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/42; Y; Y10; Y10S; Y10S148/00; Y10S148/137
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
58 words
In a process for removing an organic photoresist from a substrate in the manufacture of a semiconductor device, the steps of: burning a gaseous fuel with oxygen and a gas selected from the group consisting of nitrogen, an inert gas and combinations thereof to produce a flame, and contacting the substrate with the flame to ash the photoresist.
Claim 2
Dependent Claim
58 words
In a process for removing an organic photoresist from a substrate in the manufacture of a semiconductor device, the steps of: burning a gaseous fuel with oxygen and a gas selected from the group consisting of nitrogen, an inert gas and combinations thereof to produce a flame, and contacting the substrate with the flame to ash the photoresist.
Claim 3
Dependent Claim
20 words
The process of claim 1 wherein the substrate is heated to a temperature no greater than about 450 degrees C.
Claim 4
Dependent Claim
22 words
The process of claim 1 including the step of preheating the substrate to a temperature on the order of 100-200 degrees C.
Claim 5
Dependent Claim
19 words
The process of claim 3 wherein the substrate is preheated by placing it in contact with a heated body.
Claim 6
Dependent Claim
18 words
The process of claim 1 including the step of effecting relative movement between the flame and the substrate.
Claim 7
Dependent Claim
16 words
The process of claim 1 wherein the oxygen is present in a gas which contains oxygen.
Claim 8
Dependent Claim
27 words
The process of claim 6 wherein the fuel contains a gas selected from the group consisting of hydrogen, propane, methane, acetylene and MAPP gas, and combinations thereof.
Claim 9
Dependent Claim
14 words
The process of claim 1 wherein the nitrogen is present in a nitrogen-containing gas.
Claim 10
Dependent Claim
18 words
The process of claim 1 wherein the gas comprises on the order of 13-22% hydrogen and 78-87% nitrogen.
Claim 11
Dependent Claim
42 words
The process of claim 1 wherein the gaseous fuel is delivered to the flame through a elongated slotted opening, and the substrate is moved relative to the slotted opening to successively bring different portions of the photoresist into contact with the flame.
Claim 12
Dependent Claim
108 words
In a process for removing an organic photoresist from a substrate in the manufacture of a semiconductor device, the steps of: passing a gaseous fuel, oxygen and a gas selected from the group consisting of nitrogen, an inert gas and combinations thereof through an elongated slotted opening, burning the gaseous fuel, oxygen and gas selected from the group consisting of nitrogen, an inert gas and combinations thereof to produce a flame outside the slotted opening, and passing the substrate through the flame to successively bring different portions of the photoresist into contact with the flame to oxidize the successive portions and thereby remove the photoresist from the substrate.
Claim 13
Dependent Claim
108 words
In a process for removing an organic photoresist from a substrate in the manufacture of a semiconductor device, the steps of: passing a gaseous fuel, oxygen and a gas selected from the group consisting of nitrogen, an inert gas and combinations thereof through an elongated slotted opening, burning the gaseous fuel, oxygen and gas selected from the group consisting of nitrogen, an inert gas and combinations thereof to produce a flame outside the slotted opening, and passing the substrate through the flame to successively bring different portions of the photoresist into contact with the flame to oxidize the successive portions and thereby remove the photoresist from the substrate.
Claim 14
Dependent Claim
30 words
The process of claim 11 including the step of placing the substrate on a heated body to heat the substrate to a temperature on the order of 100-200 degrees C.
Claim 15
Dependent Claim
20 words
The process of claim 11 wherein the substrate is heated to a temperature no greater than about 450 degrees C.
Claim 16
Dependent Claim
14 words
The process of claim 11 wherein the nitrogen is present in a nitrogen-containing gas.
Claim 17
Dependent Claim
19 words
The process of claim 11 wherein the gaseous fuel contains on the order of 13-22% hydrogen and 78-87% nitrogen.
Claim 18
Dependent Claim
68 words
In a process for removing an organic photoresist from a substrate in the manufacture of a semi-conductor device, the steps of: burning a gaseous fuel with oxygen to produce a flame, burning a gas selected from a group consisting of nitrogen, an inert gas and combinations thereof with the fuel to control the temperature of the flame, and contacting the substrate with the flame to ash the photoresist.
Claim 19
Dependent Claim
68 words
In a process for removing an organic photoresist from a substrate in the manufacture of a semi-conductor device, the steps of: burning a gaseous fuel with oxygen to produce a flame, burning a gas selected from a group consisting of nitrogen, an inert gas and combinations thereof with the fuel to control the temperature of the flame, and contacting the substrate with the flame to ash the photoresist.
Claim 20
Dependent Claim
27 words
The process of claim 16 wherein the fuel contains a gas selected from a group consisting of hydrogen, propane, methane, acetylene, and MAPP gas, and combinations thereof.
Claim 21
Dependent Claim
21 words
The process of claim 16 wherein the fuel and the gas contain on the order of 13-22% hydrogen and 78-87% nitrogen.
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) | 1992-07-03 | 1993-01-02 | 1993-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-03 | 1997-01-02 | 1997-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-03 | 2001-01-02 | 2001-07-04 | $7700.00 | Window Closed / Lapsed |