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EP0457571A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Strained superlattice semiconductor structure

Assignee: Mitsubishi Electric Corp
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Filing: 1991-05-15
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Granted: —
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Expires: 2011-05-15
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Abstract

Abstract A semiconductor structure for a light-interactive semiconductor device includes first and second crystalline semiconductor cladding layers having a first lattice constant and a strained superlattice structure disposed in contact with and between the first and second cladding layers and including alternating first crystalline semiconductor quantum barrier layers having a first energy band gap and a second lattice constant and second crystalline semiconductor quantum well layers having a second energy band gap less than the first energy band gap and a third lattice constant wherein the first lattice constant is approximately equal to the average of the second and third lattice constants and the second lattice constant differs from the third lattice constant by at least about 0.5 percent of the second lattice constant. <IMAGE>

Inventors

  • 👤 Naohito C/O Mitsubishi Denki K.K. Yoshida

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-01 14:27
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/811; H10H20/812; B; B82; B82Y; B82Y20/00; H01; H01S; H01S5/00; H01S5/30; H01S5/34; H10F; H10F77/00; H10F77/10; H10F77/14; H10F77/146; H01S5/32; H01S5/3211; H01S5/3218; H01S5/3403; H01S5/3406

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 122 words
A semiconductor structure for a light-interactive semiconductor device comprising: first and second crystalline semiconductor cladding layers having a first lattice constant; and a strained superlattice structure disposed in contact with and between the first and second cladding layers and comprising alternating first crystalline semiconductor quantum barrier layers having a first energy band gap and a second lattice constant and second crystalline semiconductor quantum well layers having a second energy band gap less than the first energy band gap and-a third lattice constant wherein the first lattice constant is approximately equal to the average of the second and third lattice constants and the second lattice constant differs from the third lattice constant by at least about 0.5 percent of the second lattice constant.
Claim 2
Dependent Claim 18 words
The semiconductor structure of claim 1 wherein the second lattice constant is larger than the third lattice constant.
Claim 3
Dependent Claim 18 words
The semiconductor structure of claim 1 wherein the third lattice constant is larger than the second lattice constant.
Claim 4
Dependent Claim 36 words
The semiconductor structure of claim 1 wherein the first and second cladding layers are InP, the quantum barrier layers are In 0.35 Ga 0.65 As, and the quantum well layers are In 0.7 Ga 0.3 As.
Claim 5
Dependent Claim 36 words
The semiconductor structure of claim 1 wherein the strained superlattice structure includes a fixed number of quantum well layers and a number of quantum barrier layers equal to the number of quantum well layers plus one.
Claim 6
Dependent Claim 41 words
A light-interactive semiconductor device incorporating the semiconductor structure as claimed in any one of claims 1-5, said device comprising also: a semiconductor substrate supporting said semiconductor structure; and first and second electrodes arranged one to each side of said semiconductor structure.
Claim 7
Dependent Claim 48 words
A device as claimed in claim 6 wherein: said first electrode is in contact with the first cladding layer of said semiconductor structure; and said second electrode is in contact with the surface of said substrate that is opposite to the second cladding layer of said semiconductor substrate.
Claim 8
Dependent Claim 68 words
A semiconductor layer incorporating the light-interactive semiconductor device as claimed in either of claims 6 or 7, wherein: the first cladding layer of the semiconductor structure incorporated in said device is of one conductivity type; and the second cladding layer of the semiconductor structure incorporated in said device and the semiconductor substrate of said device are of an opposite conductivity type to said one conductivity type just mentioned.

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