Deep level transient spectroscopy studies of trapping parameters for centers in indium-doped silicon

Abstract

Deep level transient spectroscopy (DLTS) has been used to measure the low-temperature trapping parameters of defects in indium-doped silicon. Substitutional indium at Ev +0.15 eV, the indium–X center at Ev +0.11 eV, and two deeper indium related centers at Ev +0.31 eV and Ev +0.45 eV were studied. Electric fields have been found to lower the activation energies and increase the emission rates for the substitutional indium and the indium–X center. Theoretical models, including the field effect on the barrier and thermally assisted tunneling, have been used to fit the data. The capture coefficients near liquid-nitrogen temperature have been estimated as being for substitutional indium, C (In) = 7.6×10−9 cm3/sec exp (0.031 eV/kT); for the indium–X center, C(InX) = 7.7×10−8 cm3/sec exp (+0.006 eV/kT); for the Ev +0.31-eV center, C(H1) = 2×10−9 cm3/sec; and for the Ev +0.45-eV center C(H2) = 1.2×10−8 cm3/sec.