OPTICAL EPILAYERS ON SILICON SUBSTRATE - ELECTRONIC AND OPTICAL-PROPERTIES OF ZNS/SI SUPERLATTICE

The optimal epilayers on a silicon substrate are suggested to integrate the superior properties of ZnS semiconductor with the mature technology of Si. In a semiempirical tight-binding scheme, the band structures and optical transitions are studied for the (ZnS)n/(Si2)m (110) superlattices with a wide range of n,m≤20. Because of the quantum confinement effect caused by the large band-gap ZnS layers, the band-edge states are confined two dimensionally in the Si quantum wells. A single empty interface band is found lying below the conduction band. Furthermore, the influence of valence-band discontinuity has been checked over all possible energy ranges. The optical matrix elements of the superlattices are calculated and compared with those of bulk ZnS and Si. © 1995 American Institute of Physics.