| Summary: | 碩士 === 國立成功大學 === 電機工程研究所 === 83 === Atomic Layer Epitaxy is a stepwise deposition process by su-
pplying the sources materials alternatively.This deposition te-
chnique provides monolayer control of the deposited film thick-
ness and uniform growth over a large area． ZnS layers were
grown epitaxially onto (100)GaAs,(100)Si, (222)ITO substrates
under low pressure in a horizontal vaper phase epitaxial
reactor using DMZn for the group II source and H2S gas for the
group VI source.In this study, We varied the growth condition,
including change of the substrate temperature, the mole
fraction of DMZn,the mole fraction of H2S,the purge H2 duration,
the pressure of reaction chamber ...etc.In order to privide
high quality ZnS epitaxial films. In ZnS grown on GaAs,the
present process provides the mono- layer growth over a wide
range of growth condition in a self- limiting manner.High
crystalline quality of the epitaxially grown layers can be
obtained by XRD,SEM,EPMA and PL,in spite of very large lattice
mismatch (4.4 %) between ZnS and GaAs. In ZnS grown on Si and
ITO glasses,The ZnS films have high crystalline quality and the
epitaxial layers had a mirror-like surface.But the growth rate
was still at 0.7 monolayer over a wise range of growth
condition.It may be possible because the adsorption of the
reactions on the substrates is weak; and much higher flows or
flow times may be needed for monolayer
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