US5202018A
Expired / Lapsed
US
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Process for electrochemical dissolution of semiconductors
Assignee: SEMILAB FELVEZETO FIZIKAI LABORATORIUM RT A Corp OF HUNGARY
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Filing: 1991-07-11
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Granted: 1993-04-13
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Expires: 2011-07-11
Abstract
Abstract The invention relates to the electrochemical dissolution of semiconductors by alternating application of anodic and cathodic direct currents to an electrode formed by contacting a semiconductor material with an electrolyte.
Inventors
- 👤 Tamas Horanyl
- 👤 Peter Tutto
- 👤 Gabor Endredi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:21
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/60; H10P50/61; H10P50/617; Y; Y10; Y10S; Y10S204/00; Y10S204/09
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
63 words
A process for the electrochemical dissolution of a semiconductor that may be n-type or p-type, comprising contacting said semiconductor with an electrolyte suitable for its anodic dissolution and applying alternately anodic and cathodic direct currents to the interface of said semiconductor with said electrolyte such that the progress of the electrochemical dissolution is determined exclusively by the charge applied in the anodic process.
Claim 2
Dependent Claim
63 words
A process for the electrochemical dissolution of a semiconductor that may be n-type or p-type, comprising contacting said semiconductor with an electrolyte suitable for its anodic dissolution and applying alternately anodic and cathodic direct currents to the interface of said semiconductor with said electrolyte such that the progress of the electrochemical dissolution is determined exclusively by the charge applied in the anodic process.
Claim 3
Dependent Claim
20 words
The process according to claim 1 wherein within an anodic-cathodic cycle, the anodic charge/cathodic charge ratio is greater than 1:1.
Claim 4
Dependent Claim
16 words
The process according to claim 2 wherein said ratio is between about 5:1 and about 500:1.
Claim 5
Dependent Claim
21 words
The process according to claim 1 wherein the semiconductor surface contacted with said electrolyte is illuminated during the cathodic dissolution process.
Claim 6
Dependent Claim
13 words
The process according to claim 1 wherein said semiconductor comprises a compound semiconductor.
Claim 7
Dependent Claim
19 words
The process according to claim 5 wherein compound semiconductor is selected from the group consisting of GaAs and GaAlAs.
Claim 8
Dependent Claim
15 words
The process according to claim 6 wherein is semiconductor is a GaAs/GaAlAs bi-layer semiconductor structure.
Claim 9
Dependent Claim
17 words
The process according to claim 1 wherein said electrolytic dissolution is performed in a constant current mode.
Claim 10
Dependent Claim
24 words
The process according to claim 1, wherein said electrochemical dissolution is continuously and controllably determined exclusively by said charge applied in said anodic process.
Claim 11
Dependent Claim
86 words
A process for the determination of a semiconductor characteristic varying with the depth in a semiconductor that may be n-type or p-type, as a function of depth, comprising contacting said semiconductor with an electrolyte suitable for its anodic dissolution, applying alternately anodic and cathodic direct currents to the interface of the semiconductor with said electrolyte such that the progress of said electrochemical dissolution is determined by the charge applied in the anodic phase, and simultaneously measuring a parameter proportionate with said semiconductor characteristic to be determined.
Claim 12
Dependent Claim
86 words
A process for the determination of a semiconductor characteristic varying with the depth in a semiconductor that may be n-type or p-type, as a function of depth, comprising contacting said semiconductor with an electrolyte suitable for its anodic dissolution, applying alternately anodic and cathodic direct currents to the interface of the semiconductor with said electrolyte such that the progress of said electrochemical dissolution is determined by the charge applied in the anodic phase, and simultaneously measuring a parameter proportionate with said semiconductor characteristic to be determined.
Claim 13
Dependent Claim
20 words
The process according to claim 10 wherein within an anodic-cathodic cycle, the anodic charge/cathodic charge ratio is greater than 1:1.
Claim 14
Dependent Claim
16 words
The process according to claim 11 wherein said ratio is between about 5:1 and about 500:1.
Claim 15
Dependent Claim
21 words
The process according to claim 10 wherein the semiconductor surface contacted with said electrolyte is illuminated during the cathodic dissolution process.
Claim 16
Dependent Claim
13 words
The process according to claim 10 wherein said semiconductor comprises a compound semiconductor.
Claim 17
Dependent Claim
19 words
The process according to claim 14 wherein compound semiconductor is selected from the group consisting of GaAs and GaAlAs.
Claim 18
Dependent Claim
15 words
The process according to claim 15 wherein is semiconductor is a GaAs/GaAlAs bi-layer semiconductor structure.
Claim 19
Dependent Claim
19 words
The process according to claim 16 wherein within an anodic-cathodic cycle, the anodic charge/cathodic charge ratio is about 50:1.
Claim 20
Dependent Claim
17 words
The process according to claim 10 wherein said electrolytic dissolution is performed in a constant current mode.
Claim 21
Dependent Claim
14 words
The process according to claim 10 wherein said semiconductor characteristic is the carrier concentration.
Claim 22
Dependent Claim
21 words
The process according to claim 19 wherein said parameter is the capacitance of the depletion layer formed at the semiconductor/electrolyte interface.
Claim 23
Dependent Claim
20 words
The process according to claim 10 wherein said semiconductor is a multi-layer structure, and said characteristic is the layer thickness.
Claim 24
Dependent Claim
12 words
The process according to claim 10 wherein said parameter is the conductance.
Claim 25
Dependent Claim
20 words
The process according to claim 10 wherein said semiconductor is a compound semiconductor, and said parameter is the chemical composition.
Claim 26
Dependent Claim
27 words
The process according to claim 10, wherein said progress of said electrochemical dissolution is continuously and controllably determined exclusively by said charge applied in said anodic phase.
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