Characterization of II–VI: 3d crystals with the help of ultrasonic technique

摘要

The temperature dependence of ultrasonic attenuation is proposed to use for determining concentration of dopand in a diluted magnetic semiconductor. This non-destructive method can be used for the crystal in which attenuation is caused by relaxation in the Jahn–Teller system. Attenuation coefficient per the impurity ion b obtained at a fixed frequency was introduced as a parameter characterizing sensitivity of the method. This parameter was determined for a number of II–VI: 3d semiconductors: ZnSe:Ni~(2+,ZnTe:Ni~(2+), ZnSe:V~(2+), ZnSe:Cr~(2+), and ZnSe:Fe~(2+) at 54MHz. Anomalously large value of β=23 x 10~(-18) dB cm~2 was found for Cr~(2+) in ZnSe.