Group III-Sb Metamorphic Buffer on Si for p-Channel all-III-V CMOS: Electrical Properties, Growth and Surface Defects

Abstract

Group III-Sb compound semiconductors are promising materials for future CMOS circuits. Especially, In_1-xGa_xSb is considered as a complimentary p-type channel material to n-type In_1-xGa_xAs MOSFET due to the superior hole transport properties and similar chemical properties in III-Sb’s to those of InGaAs. The heteroepitaxial growth of In_1-xGa_xSb on Si substrate has significant advantage for volume fabrication of III-V ICs. However large lattice mismatch between InGaSb and Si results in many growth-related defects (micro twins, threading dislocations and antiphase domain boundaries); these defects also act as deep acceptor levels. Accordingly, unintentional doping in InGaSb films causes additional scattering, increase junction leakages and affects the interface properties. In this paper, we studied the correlations between of defects and hole carrier densities in GaSb and strained In_1-xGa_xSb quantum well layers by using various designs of metamorphic superlattice buffers.