EP0099558A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Fast plasma etch for aluminum
Assignee: Texas Instruments Inc
•
Filing: 1983-07-15
•
Granted: —
•
Expires: 2003-07-15
Abstract
Abstract An anisotropic plasma aluminum etch process uses a mixture of chlorine and recombinant, e.g. silicon tetrachloride plus boron trichloride. Etching is performed with an organic resist mask in place, although a hard masking layer may be emplaced underneath the resist. By providing a relatively high flow rate of the recombinant and a relatively low flow rate of chlorine at a relatively high total pressure, good anisotropy without undercutting is attained at reasonably high etch rates. A source of CF3 radicals is optionally also introduced, to suppress corrosion.
Inventors
- 👤 Andrew J. Purdes
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 14:31
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/20; H10P70/27; H10P70/273; C; C23; C23F; C23F4/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
87 words
A method for etching aluminum films, comprising the steps of: providing a surface; providing a uniform layer of aluminum on said surface; providing a patterned layer of masking material on said aluminum film; flowing a gaseous mixture at a total pressure of at least 700 microns over said aluminum film, said gaseous mixture comprising chlorine and a recombinant gas, wherein the flow rate of said recombinant gas is at least 10 times the flow rate of said chlorine; and applying an electrical discharge through said gaseous mixture.
Claim 2
Independent Claim
87 words
A method for etching aluminum films, comprising the steps of: providing a surface; providing a uniform layer of aluminum on said surface; providing a patterned layer of masking material on said aluminum film; flowing a gaseous mixture at a total pressure of at least 700 microns over said aluminum film, said gaseous mixture comprising chlorine and a recombinant gas, wherein the flow rate of said recombinant gas is at least 10 times the flow rate of said chlorine; and applying an electrical discharge through said gaseous mixture.
Claim 3
Dependent Claim
29 words
The method of Claim 1, wherein said gaseous mixture comprises a gas selected from the group consisting of silicon tetrachloride, boron trichloride, phosphorus trichloride, chlorinated methane, and chlorinated ethane.
Claim 4
Dependent Claim
24 words
The method of Claim 1, wherein said electric discharge step comprises applying a peak voltage of at least 200 volts to said aluminum film.
Claim 5
Dependent Claim
25 words
The method of Claim 1, wherein said electric discharge step comprises applying a power of at least one watt per square centimeter to said surface.
Claim 6
Dependent Claim
20 words
The method of Claim 1, wherein said gaseous mixture is flowed at a total pressure of at least 200 microns.
Claim 7
Dependent Claim
16 words
The method of Claim 1, wherein the partial pressure of chlorine is at least 10 microns.
Claim 8
Dependent Claim
17 words
The method of Claim 1, wherein the partial pressure of chlorine is at least 10 microns. .
Claim 9
Dependent Claim
14 words
The method of Claim 1, wherein said gaseous mixtures further comprises a trifluorocarbon-radicalforming species.
Claim 10
Dependent Claim
27 words
The process of Claim 8, wherein said chlorine is flowed at a rate which is between 2 and 4 times the flow rate of the trifluorocarbon-radical-forming species.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.