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US5817182A
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Hydrofluoric etch quenching via a colder rinse process
Assignee: Texas Instruments Inc
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Filing: 1997-03-07
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Granted: 1998-10-06
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Expires: 2017-03-07
Abstract
Abstract One embodiment of the instant invention is a method of abruptly terminating etching of a dielectric layer on a semiconductor wafer, the method comprising the steps of: removing the semiconductor wafer from the etchant, the etchant is held a first temperature; and rinsing the semiconductor wafer in a rinse solution that is at a second temperature, the second temperature is at least 5 DEG C. colder than the first temperature. Preferably, the dielectric layer is comprised of: TEOS, BPSG, PSG, thermally grown oxide, and any combination thereof. Preferably, first temperature is approximately 25 DEG C. and the second temperature is approximately 0 DEG to 5 DEG C.; or the first temperature is approximately 70 DEG to 90 DEG C. and the second temperature is approximately 10 DEG to 30 DEG C. Preferably, the etchant is comprised of a buffered or unbuffered HF acid, and the rinse solution is comprised of deionized water. The second temperature is, preferably, at least 15 DEG C. colder than the first temperature.
Inventors
- 👤 Sean C. O'Brien
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:03
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/286
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
81 words
A method of abruptly terminating etching of a dielectric layer on a semiconductor wafer, said method comprising the steps of: removing said semiconductor wafer from the etchant, said etchant is held a first temperature; rinsing said semiconductor wafer in a rinse solution that is at a second temperature, said second temperature is at least 5° C. colder than said first temperature; and wherein said etchant etches at least 20 Angstroms of said dielectric layer per minute during the prior etch step.
Claim 2
Independent Claim
81 words
A method of abruptly terminating etching of a dielectric layer on a semiconductor wafer, said method comprising the steps of: removing said semiconductor wafer from the etchant, said etchant is held a first temperature; rinsing said semiconductor wafer in a rinse solution that is at a second temperature, said second temperature is at least 5° C. colder than said first temperature; and wherein said etchant etches at least 20 Angstroms of said dielectric layer per minute during the prior etch step.
Claim 3
Dependent Claim
30 words
The method of claim 1, wherein said dielectric layer is comprised of a material selected from a group consisting of: TEOS, BPSG, PSG, thermally grown oxide, and any combination thereof.
Claim 4
Dependent Claim
12 words
The method of claim 1, wherein said first temperature is 25° C.
Claim 5
Dependent Claim
14 words
The method of claim 3, wherein said second temperature is 0° to 5° C.
Claim 6
Dependent Claim
14 words
The method of claim 1, wherein said first temperature is 70° to 90° C.
Claim 7
Dependent Claim
14 words
The method of claim 5, wherein said second temperature is 10° to 30° C.
Claim 8
Dependent Claim
17 words
The method of claim 1, wherein said etchant is comprised of a buffered or unbuffered HF acid.
Claim 9
Dependent Claim
14 words
The method of claim 1, wherein said rinse solution is comprised of deionized water.
Claim 10
Dependent Claim
19 words
The method of claim 1, wherein said second temperature is at least 15° C. colder than said first temperature.
Claim 11
Independent Claim
106 words
A method of fabricating an electrical device on a semiconductor wafer, said method comprising the steps of: subjecting said semiconductor wafer to an HF etch solution, said HF etch solution being at a first temperature and etching at least 20 Angstroms of a dielectric layer formed over said semiconductor wafer per minute; removing said semiconductor wafer from said HF etch solution; and rinsing said semiconductor wafer in a rinse solution that is at a second temperature, said second temperature being at least 20° C. colder than said first temperature so as to abruptly stop any etching by remnant HF etch solution left on said semiconductor wafer.
Claim 12
Independent Claim
106 words
A method of fabricating an electrical device on a semiconductor wafer, said method comprising the steps of: subjecting said semiconductor wafer to an HF etch solution, said HF etch solution being at a first temperature and etching at least 20 Angstroms of a dielectric layer formed over said semiconductor wafer per minute; removing said semiconductor wafer from said HF etch solution; and rinsing said semiconductor wafer in a rinse solution that is at a second temperature, said second temperature being at least 20° C. colder than said first temperature so as to abruptly stop any etching by remnant HF etch solution left on said semiconductor wafer.
Claim 13
Dependent Claim
14 words
The method of claim 10, wherein said first temperature is 70° to 90° C.
Claim 14
Dependent Claim
14 words
The method of claim 11, wherein said second temperature is 10° to 30° C.
Claim 15
Dependent Claim
19 words
The method of claim 10, wherein said HF etch solution is comprised of a buffered or unbuffered HF acid.
Claim 16
Dependent Claim
14 words
The method of claim 10, wherein said rinse solution is comprised of deionized water.
References Cited (Backward Citations)
US5294570A
Cited
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