US4920078A
Expired / Lapsed
US
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Arsenic sulfide surface passivation of III-V semiconductors
Assignee: Nytell Software LLC
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Filing: 1989-06-02
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Granted: 1990-04-24
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Expires: 2009-06-02
Abstract
Abstract A method of passivating GaAs and InGaAs by growing on the GaAs or InGaAs used for semiconducting devices a surface film of glassy As 2 S 3 which acts as a passivating layer. The film growth is preferably done by precipitating As 2 S 3 from a solution containing NH 4 OH, so as to make it basic, and then annealing the precipitated film at a temperature between the glass transition temperature (200° C.) and the melting point (315° C.) of As 2 S 3 .
Inventors
- 👤 Brian G. Bagley
- 👤 Thomas J. Gmitter
- 👤 Eli Yablonovitch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:57
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6326; H10P14/6342; H10D; H10D10/00; H10D10/01; H10D10/021; H10P14/65; H10P14/6502; H10P14/6504; H10P14/6508; H10P14/66; H10P14/668; H10P14/68; H10D62/00; H10D62/80; H10D62/85; Y; Y10; Y10S; Y10S438/00; Y10S438/958
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
82 words
A method for passivating a semiconductor, comprising: coating a film of a chalcogenide glass on a semiconductor substrate, said coating step including cleaning said substrate with a basic solution, wherein said film is coated on said substrate in a form of a precursor of said chalcogenide glass while said substrate is at a coating temperature below a melting temperature of said chalcogenide glass; and heating said precursor coated substrate at an annealing temperature above a glass transition temperature of said chalcogenide glass.
Claim 2
Independent Claim
82 words
A method for passivating a semiconductor, comprising: coating a film of a chalcogenide glass on a semiconductor substrate, said coating step including cleaning said substrate with a basic solution, wherein said film is coated on said substrate in a form of a precursor of said chalcogenide glass while said substrate is at a coating temperature below a melting temperature of said chalcogenide glass; and heating said precursor coated substrate at an annealing temperature above a glass transition temperature of said chalcogenide glass.
Claim 3
Dependent Claim
14 words
A method as recited in claim 1, wherein said chalcogenide glass comprises arsenic sulfide.
Claim 4
Dependent Claim
15 words
A method as recited in claim 2, wherein said basic solution comprises NH 4 OH.
Claim 5
Dependent Claim
17 words
A method as recited in claim 2, wherein said basic solution comprises (NH 4 ) 2 S.
Claim 6
Dependent Claim
15 words
A method as recited in claim 2, wherein said semiconductor substrate comprises a III-V semiconductor.
Claim 7
Independent Claim
39 words
A method for passivating a semiconductor, comprising: precipitating a precursor of a chalcogenide glass from a basic solution onto a semiconductor substrate; and heating said precipitated precursor at an annealing temperature below a melting temperature of said chalcogenide glass.
Claim 8
Independent Claim
39 words
A method for passivating a semiconductor, comprising: precipitating a precursor of a chalcogenide glass from a basic solution onto a semiconductor substrate; and heating said precipitated precursor at an annealing temperature below a melting temperature of said chalcogenide glass.
Claim 9
Dependent Claim
31 words
A method as recited in claim 6, wherein said chalcogenide glass comprises arsenic sulfide and said annealing temperature is above or approximately at a glass transition temperature of said arsenic sulfide.
Claim 10
Dependent Claim
15 words
A method as recited in claim 1, wherein said basic solution comprises NH 4 OH.
Claim 11
Dependent Claim
17 words
A method as recited in claim 1, wherein said basic solution comprises (NH 4 ) 2 S.
Claim 12
Dependent Claim
23 words
A method as recited in claim 1, wherein said solution comprises As 2 S 3+z and (NH 4 ) 2 S and 0<z<1.
Claim 13
Independent Claim
54 words
A method for passivating a semiconductor, comprising: flooding a semiconductor substrate with a basic solution containing a precursor of a chalcogenide glass; spin drying said substrate after said flooding step; and heating said precursor on said substrate after said spin drying step at an annealing temperature below a melting temperature of said chalcogenide glass.
Claim 14
Independent Claim
54 words
A method for passivating a semiconductor, comprising: flooding a semiconductor substrate with a basic solution containing a precursor of a chalcogenide glass; spin drying said substrate after said flooding step; and heating said precursor on said substrate after said spin drying step at an annealing temperature below a melting temperature of said chalcogenide glass.
Claim 15
Dependent Claim
25 words
A method as recited in claim 11, wherein said annealing temperature is above or approximately equal to a glass transition temperature of said arsenic sulfide.
Claim 16
Dependent Claim
19 words
A method as recited in claim 12, wherein said solution comprises As 2 S 3 and NH 4 OH.
Claim 17
Dependent Claim
25 words
A method as recited in claim 12, wherein said solution comprises As 2 S 3+z and a base and z is between 0 and 1.
Claim 18
Dependent Claim
39 words
A method as recited in claim 2, further comprising fabricating at least one electronic device in said semiconductor substrate prior to said coating step, said device including at least one region of In x Ga 1-x As, wherein 0≦x≦1.
Claim 19
Dependent Claim
24 words
A method as recited in claim 1, further comprising fabricating at least one electronic device in said semiconductor substrate prior to said coating step.
Claim 20
Independent Claim
45 words
A method of passivating a III-V semiconductor, comprising the steps of: applying to a surface of a III-V semiconductor a solution containing arsenic sulfide and ammonium hydroxide; and then heating said surface in a non-oxidizing atmosphere at a temperature between 200° C. and 315° C.
Claim 21
Independent Claim
45 words
A method of passivating a III-V semiconductor, comprising the steps of: applying to a surface of a III-V semiconductor a solution containing arsenic sulfide and ammonium hydroxide; and then heating said surface in a non-oxidizing atmosphere at a temperature between 200° C. and 315° C.
Claim 22
Dependent Claim
23 words
A method as recited in claim 17, wherein said semiconductor comprises GaAs and said temperature is between approximately 290° C. and 315° C.
Claim 23
Independent Claim
40 words
A method for passivating a semiconductor, comprising: coating a film of a chalcogenide glass comprising arsenic sulfide on a semiconductor substrate comprising In x Ga 1-x As, wherein 0≦x≦1, said coating step including cleaning said substrate with a basic solution.
Claim 24
Independent Claim
40 words
A method for passivating a semiconductor, comprising: coating a film of a chalcogenide glass comprising arsenic sulfide on a semiconductor substrate comprising In x Ga 1-x As, wherein 0≦x≦1, said coating step including cleaning said substrate with a basic solution.
Claim 25
Dependent Claim
14 words
A method as recited in claim 6 wherein said chalcogenide glass comprises arsenic sulfide.
Claim 26
Dependent Claim
14 words
A method as recited in claim 11, wherein said chalcogenide glass comprises arsenic sulfide.
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