cw CO2 and ruby laser annealing of ion-implanted Hg1−xCdx Te

Abstract

The effects of cw CO₂ and Q‐switched ruby laser beam irradiation on donor (B, In) and acceptor (P) ion‐implanted Hg_1−xCd_x Te (x = 0.2, 0.3) are reported. Rutherford backscattering and particle induced x‐ray emission measurements for channeled and nonchanneled particles were used to investigate the crystal quality and its composition near the surface. It is shown that annealing by cw CO₂ laser irradiation (120 W/cm², 0.2 s) results in good crystal regrowth. Irradiation by light from pulsed ruby lasers (0.15 J/cm², 50 ns) even though to a certain extent does anneal the damage, is accompanied by the dislodging of Hg atoms from the near‐surface region. The present results thus explain our findings that electrical activation of donor and acceptor implants in HgCdTe can be achieved by cw CO₂ laser annealing, but not by pulsed ruby laser irradiations.