Experimental and Simulation Analysis of Thermal Vertical Directional Solidification Grown Ni Doped Bulk GASB

Abstract

Due to high hole mobility, p-GaSb is an attractive III-V semiconducting material for high performance p-channel metal-oxide semiconductor field effect transistor (p-MOSFET). For that growth of undoped and Ni doped GaSb bulk crystal by thermal vertical directional solidification has been reported in this paper. Both structural and electrical characterization was carried out for both the samples. X-ray diffraction (XRD) analysis confirms that the compound grown is polycrystalline in nature which has been supported by scanning electron microscope (SEM) image. The carrier charge density and mobility were measured by Hall Effect measurement in the temperature range 78K and 300K. From the sign of Hall co-efficient the grown material was confirmed p-type. The Current-Voltage (I-V) characteristic was studied for the sample i.e. experimentally grown and also simulated using TCAD at 78K and 300K. The temperature dependence of the hole mobility were also investigated by TCAD tool using the models Auger recombination, Shockley-Read-Hall (SRH) and Band-gap narrowing (BGN). Comparison of experimental and simulated temperature dependencies of mobility shows good agreement, while their difference at some points suggests the contribution of compensating impurities.