US4454008A
Expired / Lapsed
US
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Electrochemical method for producing a passivated junction in alloy semiconductors
Assignee: United States Department of the Army
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Filing: 1983-02-24
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Granted: 1984-06-12
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Expires: 2003-02-24
Abstract
Abstract A ternary or more complex semiconductor alloy is treated to form simultansly a junction beneath its surface and to passivate the same surface. The treatment consists of connecting the semiconductor to one electrode of an electrolytic circuit, immersing it in an electrolyte which may contain a leachant, and energizing between electrolytic circuit electrodes with a substantially square electric current wave with a direct current average value. After a predetermined time, the semiconductor is removed from the electrolyte, is disconnected from the electrolyte, and is washed, rinsed, and dried. During the process the electric current causes ions of the semiconductor to migrate toward its surface, where they enter the electrolyte. This depletion of ions effectively forms a junction; the current also causes oxidation of the semiconductor surface for passivation.
Inventors
- 👤 Juergen L. W. Pohlmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 02:51
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; C; C25; C25D; C25D11/00; C25D11/02; C25D11/32; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6324
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
172 words
A method of electrochemically producing, in the electrolyte of a electrolytic circuit having two electrodes, on at least one surface of at least a ternary semiconductor alloy layer with two of its components being cations and the other an anion, a passivated junction, including the steps of: (a) connect the layer to one electrode of the electrolytic circuit; (b) energize between the one electrode and the other electrode with an essentially square wave of current and an increasing square-wave modulated voltage, both said current and said voltage having cathodic phases of less amplitudes than their anodic phases, whereby the two cations of the layer migrate at different rates toward the one surface of the layer in response to the voltage, whereby one cation passes into the electrolyte at a greater rate than the other one, and whereby said anion forms an oxide on said one surface; (c) remove the layer from the electrolyte; (d) deenergize the electrodes; (e) disconnect the layer from the one electrode; and wash, rinse, and dry the layer.
Claim 2
Independent Claim
172 words
A method of electrochemically producing, in the electrolyte of a electrolytic circuit having two electrodes, on at least one surface of at least a ternary semiconductor alloy layer with two of its components being cations and the other an anion, a passivated junction, including the steps of: (a) connect the layer to one electrode of the electrolytic circuit; (b) energize between the one electrode and the other electrode with an essentially square wave of current and an increasing square-wave modulated voltage, both said current and said voltage having cathodic phases of less amplitudes than their anodic phases, whereby the two cations of the layer migrate at different rates toward the one surface of the layer in response to the voltage, whereby one cation passes into the electrolyte at a greater rate than the other one, and whereby said anion forms an oxide on said one surface; (c) remove the layer from the electrolyte; (d) deenergize the electrodes; (e) disconnect the layer from the one electrode; and wash, rinse, and dry the layer.
Claim 3
Dependent Claim
40 words
The method as set forth in claim 1 further including the steps of: (a') energize the layer with a cathodic voltage between steps (a) and (b), and; (b') energize the layer with a anodic voltage between steps (b) and (c).
Claim 4
Dependent Claim
7 words
The product as produced by claim 1.
Claim 5
Dependent Claim
7 words
The product as produced by claim 2.
Claim 6
Dependent Claim
15 words
The method as set forth in claim 1 wherein the electrolyte contains a complexing agent.
Claim 7
Dependent Claim
15 words
The method as set forth in claim 2 wherein the electrolyte contains a complexing agent.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-12 | 1987-12-12 | 1988-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-12 | 1991-12-12 | 1992-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-12 | 1995-12-12 | 1996-06-12 | $7700.00 | Window Closed / Lapsed |