Optical imaging of dislocations in strained-layer superlattices and lattice-mismatched epilayers

Conference · Tue Jan 01 04:00:00 EST 1985

OSTI ID:6179052

Gourley, P L; Biefeld, R M; Dawson, L R

We have developed a convenient photoluminescence microimaging technique to probe misfit dislocations in epitaxially grown semiconductor alloys and multilayers. Using this technique, we have examined the microscopic optical quality of thick (approx.1 ..mu..m) III-V semiconductor epitaxial layers, mismatched to their substrates. The layers include several kinds of (100) strained-layer superlattices (GaP/GaAs/sub x/P/sub 1-x/ on GaP and GaAs/GaAs/sub 1-x/P on GaAs grown by MOCVD, and GaAs/In/sub x/Ga/sub 1-x/As on GaAs grown by MBE) and associated alloys. For each type of superlattice, we have studied a large number of samples corresponding to different compositions and layer thicknesses. The results show that misfit dislocations can be completely eliminated in the uppermost layers of the strained-layer superlattices if these structures have thin layers, less than the critical thickness for elastic accommodation, and sufficient numbers of interfaces to block threading dislocations.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6179052
• Report Number(s): SAND-85-2664C; CONF-851217-16; ON: DE86004620
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
ARSENIC COMPOUNDS
ARSENIDES
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DISLOCATIONS
EPITAXY
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
GALLIUM PHOSPHIDES
IMAGES
INDIUM ARSENIDES
INDIUM COMPOUNDS
LAYERS
LINE DEFECTS
LUMINESCENCE
MICROSTRUCTURE
PHOSPHIDES
PHOSPHORUS COMPOUNDS
PHOTOLUMINESCENCE
PNICTIDES
SUPERLATTICES