CI을 첨가한 CdTe결정의 열처리효과에 관한 연구

Abstract

CdTe : Cl (5wt-%)결정을 Bridgman법으로 생장시키어 그 열처리 효과를 보았다. 열처리된 시료들은 van der Pauw법으로 Hall효과측정을 하였다. 생장한 시료는 n형으로 비저항, Hall이동도, carrier농도는 300K에서 각각 5.0×10^(17)ohm·㎝, 590㎠/V·sec, 2.1×10^(17)㎝^(-3)이었다. 1기압의 Cadmium분위기 속에서 700℃, 3시간 열처리한 시료는 각각 3.8×10^(-3)ohm·㎝, 170㎠/V·sec, 9.7×10^(18)㎝^(-3) 이었고, 진공에서 700℃, 10시간 열처리한 시료는 각각 2.3×10^(1)ohm·㎝, 530㎠/V·sec, 5.1×10^(14)㎝^(-3)이었다. 이들 시료에 대하여 12K에서 PL측정을 하였는데 1.41eV에서 1.45ev사이에 넓은 발광이 있었다. As-grown, Cadmium분위기, 진공에서 열처리한 시료의 PL peak 에너지는 각각 1.429ev, 1.449eV, 1.430ev이었다.;CdTe: C1 (5wt-%) crystal was grown by Bridgman method and its annealing effects were studied. Hall measurements were conducted on variously heat-treated samples using the van der Pauw method. The conduction type of as-grown sample was n-type, and the resistivity, Hall mobility, and carrier concentration at 300K were 5.0×10^(-2) Ω·cm, 590 ㎠/V·sec, and 2.2×10^(17) ㎝^(-3), respectively. The sample heat-treated at 700℃ in 1 atm Cd-vapor pressure for 3 hours revealed that 3.8×10^(-3)Ω·cm, 170 ㎠/V·sec, and 9.7×10^(18) ㎝^(-3), respectively. On the ohter hand, the sample heat-treated at 700℃ in vacuum for 10 hours showed 2.3×10^(1)Ω·cm, 530 ㎠/V·sec, and 5.1×10^(14) ㎝^(-3), respectively. Photoluminescence measurement at 12K was performed for the above samples on the broad band emission (1.41∼1.45eV). The obtained peak energies of the emission spectra were 1.429eV, 1.449eV, and 1.430eV for as-grown and heat-treated in Cd-vapor and vacuum, respectively.