MOLECULAR-BEAM EPITAXY OF INSB ON SI SUBSTRATES USING FLUORIDE BUFFERLAYERS

The molecular beam epitaxy of InSb/Si structures was accomplished usin g group IIa fluoride buffer layers. InSb growth was initiated by openi ng the In and Sb shutters simultaneously at substrate temperatures bet ween 300 degrees C and 400 degrees C, producing In-terminated InSb(111 )-A surfaces on CaF2/Si(111) substrates. Reflection high-energy electr on diffraction, electron channeling, and high resolution x-ray diffrac tion measurements indicated that the InSb layers were of good crystall ine quality. Electron mobilities at room temperature were as high as 6 5 000 cm2/V s for an 8-mu m-thick InSb layer grown on CaF2/Si(111). On CaF2/Si(001) substrates, the InSb layers grew in the (111) orientatio n with two domains 90 degrees apart. These InSb layers and ones grown on BaF2/CaF2/Si(111) substrates exhibited inferior electrical and stru ctural properties compared to structures grown on CaF2/Si(111) substra tes. (C) 1997 American Institute of Physics.