Epitaxial Growth of Gallium Arsenide on Germanium Substrates

Abstract

Morphological and etching studies on films of gallium arsenide deposited on germanium substrates have revealed twin planes, grains, and stacking faults. The evidence suggests that these defects are related to the faceting of the substrafe and to the presence of oxide films.The deposition of gallium arsenide films on low index planes of germanium substrates has been described (i-4), and recently films altogether free of stacking faults have been grown (5). We have found it much more difficult to avoid the formation of faults in films grown on ~111} surfaces of germanium than in films grown on gallium arsenide substrates. The aim of the work described in this communication was to examine the causes of fault formation when germanium was used as substrate. ExperimentalFlow system.--A stream of hydrogen containing arsenic trichloride was passed over gallium arsenide in an open tube. The resulting gas mixture then flowed over germanium substrates in a lower temperature region. The substrates were lying horizontally on semicylindrical holders so that some growth

Preparation of Epitaxial Ga[sub x]In[sub 1−x]As

“…For InAs-rich alloys, defects took the form of short line imperfections oriented along <110> directions. These line imperfections appear to be (100) analogs of the (111) stacking faults in epitaxial GaAs described by Gabor (10).…”

Structural, morphological, and band alignment properties of GaAs/Ge/GaAs heterostructures on (100), (110), and (111)A GaAs substrates

“…56 Very limited experimental band offset data for the GaAs/Ge/GaAs heterostructures are available to date on the (111)A GaAs substrate, 58 which has a significant advantage for the enhancement of electron mobility in Ge material. Furthermore, the heteroepitaxial growth of GaAs on (111) Ge surface exhibits poor surface morphology due to formation of stacking faults 59 compared to other orientations; however, antiphase domain boundaries are never observed on this orientation than on (100) or (110) Ge substrates 60 though (111) is a polar surface. This prompted us to determine the band offset value carefully of each interface of GaAs/Ge/GaAs heterostructures grown on (100), (110), and (111)A GaAs substrates and its correlation in a relationship in structural and morphological properties of GaAs/Ge/GaAs heterostructures grown in situ using two separate MBE chambers, as described earlier.…”

Epitaxial Growth of Gallium Arsenide on Germanium Substrates

“…The f o r m a t i o n of stacking faults in epitaxial films of g a l l i u m a r s e n i d e g r o w n on low i n d e x planes of g e r m a n i u m s u b s t r a t e s has b e e n described in P a r t I of this series (1). E v e n t h o u g h it is desirable to p r ev e n t the 9 S e v e r a l m e t h o d s w e r e used for the p r e p a r a t i o n of concave surfaces.…”

“…For e x a m p l e a " K o d a k Photo Resist" p a t t e r n , consisting of a series of c h a n n e l s separ a t i n g s q u a r e areas was etched into a (111} Czochralski crystal. The etching solution consisted of H F [ 1 ] : H202[1] : H 2 0 [ 4 ] . Depressions w e r e also p r e p a r e d by a jet etching t e c h n i q u e (2).…”

“…Details of the deposition e x p e r i m e n t s i n v o l v i n g arsenic trichloride as the t r a n s p o r t i n g agent in a n open flow s y s t e m h a v e b e e n described (1,3). I n one e x p e r i m e n t w i t h a w e b substrate, zinc chloride was used as the t r a n s p o r t i n g a g e n t in a sealed tube.…”