The Features of Electronic Conduction in InAs

Abstract

The electrical properties of n-type crystals of InAs compound, grown from stoichiometric melt by the horizontal zone melting method, have been investigated in the temperature range of 4.2 K-300 K before and after fast neutron irradiation up to high integral fluences of 2×10¹⁸n?cm^-2. At a fixed temperature electrons concentration (n) increases almost by one order during irradiation, and practically does not change with increasing of temperature. n increases only slightly by increasing of temperature near 300 K, both before and after irradiation. When  ? 4×10¹⁸cm^-3 the change of  during irradiation is negligible. Comparison of experimental data of mobility with theory shows that the privileged scattering mechanism of electrons at 300 K is scattering on optical phonons in InAs with  10¹⁶-10¹⁷ cm^-3 and scattering on ions of impurity in InAs with n~10¹⁸-10¹⁹ cm^-3. The analysis shows that during irradiation point type scattering centers of donor-type structural defects with shallow levels in the forbidden zone appear. Consequently, the mobility decreases during irradiation. At 300 K in  sample with electrons concentration of 3×10¹⁶ cm^-3 the mobility decreases by 5 times after irradiation, which is equivalent to the formation of 1.5×10¹⁹cm^-3 charged point scattering centers.