EP0010657A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Selective etching of polymeric materials embodying silicones via reactor plasmas
Assignee: General Electric Co
•
Filing: 1979-10-11
•
Granted: —
•
Expires: 1999-10-11
Abstract
Abstract Silicon is employed as a masking material (30) for the selective plasma chemical etching of a coating material (28) of a polyimidesilicone copolymer disposed on selective surface (12) areas of electronic devices (10).
Inventors
- 👤 Leonard Stein
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 13:17
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/286; H10P50/287
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
344 words
A method for the selective chemical etching of a cured layer of a silicone-polyimide copolymer material disposed on a surface of a body to open windows therein to expose selected surface portions of the surface thereat characterized by the process steps of: (a) forming a layer of a cured silicone-polyimide copolymer material on a processed body of semiconductor material, the copolymer material consisting of a reaction product of a silicon-free organic diamine, an organic tetracarboxylic dianhydride and a polysiloxane which when cured has the recurring structural units of the formula: with from 5 to 50 mol percent intercondensed structural units of the formula: wherein R is a divalent hydrocarbon radical; R' is a monovalent hydrocarbon radical; Q is a divalent silicon-free organic radical which is the residue of an organic diamine; x is an integer having a value of 1-4, and m and n are integers greater than 1. (b) depositing a layer of silicon of a predetermined thickness on the layer of silicone-polyimide copolymer material; (c) depositing a photoresist material on the layer of silicon; (d) processing the layer of photoresist material to open one or more windows therein to expose a selected surface area of the layer of silicon thereat; (e) chemically etching selectively the exposed silicon in a plasma of CF /4% oxygen at about 100 watts RF power at a pressure range of from about 0. 3 torr to about 0.5 torr to open one or more windows therein, aligned with the respective windows in the layer of photoresist, to expose selected surface areas of the layer of silicone-polyimide copolymer material thereat, and (f) chemically etching the layer of silicone-polyimide copolymer material selectively in an oxygen plasma at a range of RF power from about 200 watts to about 400 watts at a range of pressure from about 0. 8 torr to about 2. 0 torr to open one or more windows in the copolymer layer, aligned with the respective windows of the layer of silicon, to expose the selected surface areas of the surface of the processed body thereat.
Claim 2
Independent Claim
344 words
A method for the selective chemical etching of a cured layer of a silicone-polyimide copolymer material disposed on a surface of a body to open windows therein to expose selected surface portions of the surface thereat characterized by the process steps of: (a) forming a layer of a cured silicone-polyimide copolymer material on a processed body of semiconductor material, the copolymer material consisting of a reaction product of a silicon-free organic diamine, an organic tetracarboxylic dianhydride and a polysiloxane which when cured has the recurring structural units of the formula: with from 5 to 50 mol percent intercondensed structural units of the formula: wherein R is a divalent hydrocarbon radical; R' is a monovalent hydrocarbon radical; Q is a divalent silicon-free organic radical which is the residue of an organic diamine; x is an integer having a value of 1-4, and m and n are integers greater than 1. (b) depositing a layer of silicon of a predetermined thickness on the layer of silicone-polyimide copolymer material; (c) depositing a photoresist material on the layer of silicon; (d) processing the layer of photoresist material to open one or more windows therein to expose a selected surface area of the layer of silicon thereat; (e) chemically etching selectively the exposed silicon in a plasma of CF /4% oxygen at about 100 watts RF power at a pressure range of from about 0. 3 torr to about 0.5 torr to open one or more windows therein, aligned with the respective windows in the layer of photoresist, to expose selected surface areas of the layer of silicone-polyimide copolymer material thereat, and (f) chemically etching the layer of silicone-polyimide copolymer material selectively in an oxygen plasma at a range of RF power from about 200 watts to about 400 watts at a range of pressure from about 0. 8 torr to about 2. 0 torr to open one or more windows in the copolymer layer, aligned with the respective windows of the layer of silicon, to expose the selected surface areas of the surface of the processed body thereat.
Claim 3
Dependent Claim
23 words
The method of Claim 1 characterized in that the photoresist material is removed simultaneously with the plasma etching of the polyimide-silicone copolymer material.
Claim 4
Independent Claim
24 words
The method of Claims 1 or 2 characterized in that the layer of silicon is from about 500Å to about 2, 000Å in thickness.
Claim 5
Dependent Claim
17 words
The method of Claim 3 characterized in that the layer of silicon is about 1000Å in thickness.
Claim 6
Independent Claim
22 words
The method of Claims 3 or 4 characterized in that the depositing of the layer of silicon is by electron beam deposition.
Claim 7
Dependent Claim
53 words
The method of Claim 1 characterized by the step of selective etching of the exposed silicon of preheating the processed body in a plasma of nitrogen for a sufficient period of time to raise the temperature of the processed body to about that temperature required for uniform plasma chemical etching of the silicon.
Claim 8
Dependent Claim
46 words
The method of Claim 6 characterized in that the nitrogen plasma is formed at an RF power of about 100 watts at a pressure of about 0.5 torr, and the processed body is heated to a temperature ranging from 65 o C to 85 o C.
Claim 9
Independent Claim
30 words
The method of any one of Claims 1 to 7 characterized in that the chemical etching of the exposed silicon is practiced in a plasma of Freon 14 containing oxygen.
Claim 10
Dependent Claim
18 words
The method of Claim 8 characterized in that the plasma is Freon 14 containing 4% oxygen by volume.
Claim 11
Dependent Claim
41 words
The method of Claim 9 characterized in that the plasma forming gas mixture is Freon 14 containing 4% oxygen by volume and the plasma is formed at a RF power of about 100 watts at a pressure of about 0. torr.
Claim 12
Dependent Claim
30 words
The method of Claim 10 characterized in that the flow of the Freon 14 containing 4% oxygen by volume is from about 100cc per minute to about 150cc per minute.
Claim 13
Independent Claim
18 words
The method of any one of Claims 1 to 11 characterized in exposed polyimide-silicone copolymer material is chemically
Claim 14
Dependent Claim
45 words
The method of Claim 12 characterized in that the plasma of oxygen is formed at a range of RF power of from about 200 watts to about 400 watts at a range of pressure of from about 0. 8 torr to about 2. 0 torr.
Claim 15
Dependent Claim
16 words
The method of Claim 13 characterized in that the oxygen gas flow is about 300 CCPM.
Claim 16
Independent Claim
25 words
The method of Claims 13 or 14 characterized in that the RF power is about 300 watts, and the pressure is about 1. 6 torr.
Claim 17
Dependent Claim
28 words
The method of Claim 1 characterized by the step of introducing from 10% by volume to 15% by volume of CF 4 into the oxygen of the plasma.
Claim 18
Dependent Claim
21 words
The method of Claim 16 characterized in that the plasma is formed at about 50 watts and about 0.2 torr pressure.
References Cited (Backward Citations)
DE2227344A1
Cited
US3975252A
Cited
FR2309976A1
Cited
US4040874A
Cited
US3986912A
Cited
DE2739847A1
Cited
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.