12.1 INTRODUCTION

InSb has a small bandgap of 0.18 eV and is sensitive to longer wavelengths of the region of 3 5 ?m so that it is a promising material for infrared detectors. ^{1 5} It is also an important substrate material for infrared detectors in the 9 12 ?m long wavelength region.1 Since the effective mass of electrons of InSb is very low and therefore the electron mobility very high, InSb is an important material for Hall devices ^{5 8} and magnetoresistance devices.9 The crystal growth of InSb is reviewed by Liang10 and Matsumoto.11

12.2 PHYSICAL PROPERTIES

InSb has a small bandgap and low effective mass so that it has a large electron mobility up to 78,000 cm ²/V.sec. This is the reason why InSb is a very interesting material for IR detectors, Hall devices and magnetoresistance devices. The main physical properties of InSb can be found in Ref. 12 and some data are summarized in Table 12.1. The phase diagrams of InSb have been reported in Refs. 13 and 14, and a typical X-T phase diagram is shown in Fig. 12.1. In and Sb self-diffusion coefficients have been measured in the temperature range of 400 500 C by the radioactive tracer diffusion method.15 The self-diffusion coefficient of In is

(12.1)

and that of Sb is

(12.2)