Electron transport in mesoscopic devices fabricated from indium antimonide/aluminum indium antimonide heterostructures grown by molecular beam epitaxy .

Abstract

Among all binary III-V semiconductors, InSb has the highest intrinsic electron mobility, the narrowest band gap, and the smallest electron effective mass (m* = 0.0139m0). These characteristics make InSb quantum wells (QWs) with remotely doped Al xIn1-xSb barriers promising for several novel devices. The promise of InSb QWs for spin transistors has been shown recently by experiments that demonstrate ballistic transport and a large zero-field spin splitting. Mesoscopic magnetoresistors that take advantage of the high electron mobility in InSb QWs at room temperature are currently being developed for read head applications. In order to realize such devices, InSb quantum wells were grown using molecular beam epitaxy. For some applications, the carriers are required to travel ballistically through the channel. We fabricated four-terminal structures and quantum point contacts to explore the unique effects of narrow-gap properties on ballistic transport. There is also an ongoing effort to increase the room and low temperature mobilities in these quantum well structures. The structures, so far, have been optimized to obtain room and low temperature mobilities of nearly 36, 000 cm2/Vs and 200,000 cm2/Vs respectively. An attempt is also made to estimate and decrease the parallel conduction through these structures at room temperature.