Electrical characterization of wafer-bonded Ge(111)-on-insulator substrates using four-point-probe pseudo-metal-oxide-semiconductor field-effect transistor method

摘要

The electrical properties of wafer-bonded n-type Ge(111)-on-insulator (Ge(111)-O1) substrates were characterized using a four-point-probe pseudo-metal-oxide-semiconductor field-effect transistor (pseudo-MOSFET) method. Average electron and hole mobilities in the Ge(111)-O1 channel were measured to be ~1000cm~2/Vs in accumulation mode and ~310cm~2/Vs in inversion mode, respectively. The measured mobility strongly depended on the sample position, due to the spatially inhomogeneous distribution of the interface states. Despite the existence of interface states, the carrier mobility exhibited a high value demonstrating the prospect of waferbonded Ge( 111 )-01 as a channel material in MOSFETs.