US4070797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nitrogen-free anionic and non-ionic surfactants in a process for producing a haze-free semiconduct
Assignee: Siltronic AG
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Filing: 1976-07-02
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Granted: 1978-01-31
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Expires: 1996-07-02
Abstract
Abstract Process for making haze-free surfaces of semiconductor bodies which comprs a first step of polishing the surface by means of a polishing agent containing at least one member of the group consisting of quartz, silica, silicates and fluosilicates, and a second step of polishing the surface by means of a polishing agent containing in addition to the above defined agents from 0.1 to 10% by weight calculated on the polishing agent of a nitrogen-free surfactant selected from the group consisting of anionic and non-ionic surfactants, and a mixture thereof.
Inventors
- 👤 Rudolf Griesshammer
- 👤 Helmut Kirschner
- 👤 Gunther Lechner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:32
CPC Classifications
H; H10; H10P; H10P52/00; H10P52/40; H10P52/402
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
93 words
In a process for the production of a semiconductor having a haze-free surface by polishing the semiconductor with a polishing agent containing at least one member of the group consisting of quartz, silica, silicates and fluosilicates, the improvement which comprises further polishing the semiconductor in a second polishing step with a modified polishing agent containing said first-mentioned polishing agent and from 0.1 to 10% by weight, calculated on the weight of said first-mentioned polishing agent, of a nitrogen-free surfactant selected from the group consisting of anionic and non-ionic surfactants and a mixture thereof.
Claim 2
Dependent Claim
93 words
In a process for the production of a semiconductor having a haze-free surface by polishing the semiconductor with a polishing agent containing at least one member of the group consisting of quartz, silica, silicates and fluosilicates, the improvement which comprises further polishing the semiconductor in a second polishing step with a modified polishing agent containing said first-mentioned polishing agent and from 0.1 to 10% by weight, calculated on the weight of said first-mentioned polishing agent, of a nitrogen-free surfactant selected from the group consisting of anionic and non-ionic surfactants and a mixture thereof.
Claim 3
Dependent Claim
12 words
The process according to claim 1, wherein the added surfactant is nonylphenolpolyglycolether.
Claim 4
Dependent Claim
13 words
The process according to claim 1, wherein the added surfactant is isododecylbenzene sulfonate.
Claim 5
Dependent Claim
34 words
The process as claimed in claim 1, wherein each polishing agent comprises a silicate of a metal of the group consisting of zirconium, iron, lead, nickel, cobalt, magnesium, calcium, strontium, barium, zinc and aluminium.
Claim 6
Dependent Claim
30 words
The process as claimed in claim 1 wherein each polishing agent comprises a fluosilicate of a metal of the group consisting of sodium, potassium, magnesium, calcium, barium, aluminium, and zinc.
Claim 7
Dependent Claim
14 words
The process as claimed in claim 1 wherein each polishing agent contains an alkali.
Claim 8
Dependent Claim
38 words
The process as claimed in claim 1 wherein the polishing agent used for the second polishing step contains the surfactant in an amount within the range of from 0.5 to 5% by weight, calculated on the polising agent.
Claim 9
Dependent Claim
36 words
The process as claimed in claim 1 wherein the duration of the first polishing step is from 10 minutes to 2 hours and the duration of the second polishing step is from 2 to 10 minutes.
Claim 10
Dependent Claim
20 words
The process as claimed in claim 1 wherein the semiconductor is selected from the group consisting of silicon and germanium,
Claim 11
Dependent Claim
26 words
The process according to claim 1, wherein the size of the solid components of the polishing agent is in the range of 5 to 200 μm.
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Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-30 | 1981-08-01 | 1982-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-30 | 1985-08-01 | 1986-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-30 | 1989-08-01 | 1990-01-31 | $7700.00 | Window Closed / Lapsed |