Pulsed laser annealing of selenium implanted InP

Abstract

Rutherford back-scattering, Hall effect and Nomarski interference microscopy have been used to study 200 keV selenium ions implanted into InP in the dose range 1*10¹⁴ to 1*10¹⁵ cm^-2. Samples were irradiated with single pulses from a Q-switched ruby laser in the energy range 0.2 to 2.2 J cm^-2. It was found that capless laser irradiation does not allow complex recrystallisation of damaged InP, and an energy density of 0.3 J cm^-2 causes surface decomposition, thus producing indium-rich surface layers. To ensure that the measured electrical properties were due to the implanted atoms alone it was found necessary to thermally anneal samples at 4000DC for 5 min after the laser irradiation. The activity was 26% and the mobility of 300 cm² V^-1 s^-1 for a dose of 1*10¹⁵ Se⁺ cm^-2 irradiated at 0.5 J cm^-2.