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Title: Lattice constant grading in the Al.sub.y Ca.sub.1-y As.sub.1-x Sb.sub.x alloy system

Abstract

Liquid phase epitaxy is employed to grow a lattice matched layer of GaAsSb on GaAs substrates through the compositional intermediary of the III-V alloy system AlGaAsSb which acts as a grading layer. The Al constituent reaches a peak atomic concentration of about 6% within the first 2.5.mu.m of the transition layer, then decreases smoothly to about 1% to obtain a lattice constant of 5.74 A. In the same interval the equilibrium concentration of Sb smoothly increases from 0 to about 9 atomic percent to form a surface on which a GaAsSb layer having the desired energy bandgap of 1.1 ev for one junction of an optimized dual junction photovoltaic device. The liquid phase epitaxy is accomplished with a step cooling procedure whereby dislocation defects are more uniformly distributed over the surface of the growing layer.

Inventors:
 [1]
  1. Palo Alto, CA
Issue Date:
OSTI Identifier:
863780
Patent Number(s):
4246050
Assignee:
Varian Associates, Inc. (Palo Alto, CA)
Patent Classifications (CPCs):
H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01L - SEMICONDUCTOR DEVICES
Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
DOE Contract Number:  
E(04-3)-1250
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
lattice; constant; grading; 1-y; 1-x; sb; alloy; liquid; phase; epitaxy; employed; grow; matched; layer; gaassb; gaas; substrates; compositional; intermediary; iii-v; algaassb; constituent; reaches; peak; atomic; concentration; transition; decreases; smoothly; obtain; 74; interval; equilibrium; increases; percent; form; surface; desired; energy; bandgap; junction; optimized; dual; photovoltaic; device; accomplished; step; cooling; procedure; whereby; dislocation; defects; uniformly; distributed; growing; uniformly distribute; transition layer; lattice constant; lattice matched; atomic percent; liquid phase; photovoltaic device; uniformly distributed; gaas substrate; phase epitaxy; energy band; energy bandgap; cooling procedure; compositional intermediary; dislocation defects; gaas substrates; gaassb layer; whereby dislocation; iii-v alloy; sb layer; matched layer; constant grading; /117/136/438/

Citation Formats

Moon, Ronald L. Lattice constant grading in the Al.sub.y Ca.sub.1-y As.sub.1-x Sb.sub.x alloy system. United States: N. p., 1981. Web.
Moon, Ronald L. Lattice constant grading in the Al.sub.y Ca.sub.1-y As.sub.1-x Sb.sub.x alloy system. United States.
Moon, Ronald L. Thu . "Lattice constant grading in the Al.sub.y Ca.sub.1-y As.sub.1-x Sb.sub.x alloy system". United States. https://www.osti.gov/servlets/purl/863780.
@article{osti_863780,
title = {Lattice constant grading in the Al.sub.y Ca.sub.1-y As.sub.1-x Sb.sub.x alloy system},
author = {Moon, Ronald L},
abstractNote = {Liquid phase epitaxy is employed to grow a lattice matched layer of GaAsSb on GaAs substrates through the compositional intermediary of the III-V alloy system AlGaAsSb which acts as a grading layer. The Al constituent reaches a peak atomic concentration of about 6% within the first 2.5.mu.m of the transition layer, then decreases smoothly to about 1% to obtain a lattice constant of 5.74 A. In the same interval the equilibrium concentration of Sb smoothly increases from 0 to about 9 atomic percent to form a surface on which a GaAsSb layer having the desired energy bandgap of 1.1 ev for one junction of an optimized dual junction photovoltaic device. The liquid phase epitaxy is accomplished with a step cooling procedure whereby dislocation defects are more uniformly distributed over the surface of the growing layer.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1981},
month = {1}
}