Amorphous Si-Ni alloys were prepared by high vacuum evaporation.
Two methods of evaporation were employed ; the one is coevaporation with electron gun and tungsten basket, and the other is evaporation of Si-Ni alloy after forming by electron gun bombardment.
The effect of Ni in a-Si on transport properties was investigated through the measurement of optical gap and temperature dependance of conductivity.
The results show that the room temperature donductivity was increased and the temperature range for the singly octivated process was shifted to higher temperature side with increasing contents of Ni, while hopping paramenter To, optical gap and Fermi level were decreased.
These indicated that the localized states were increased with increased concentration of Ni in a-Si Hydrogen diffusion at 350℃ resulted in the decrease in electrical conductivity and the width of optical gap.
비정질 Si-Ni alloy는 하나의 e-gun crucible에 Si과 Ni을 올려놓고 증착하는 방법과 e-gun과 Tungsten basket을 사용한 Coevaporation 방법에 의해 얻어졌다.
제작된 시료의 optical gap과 온도에 따른 전기 전도도가 측정되었는데 Ni이 증가함에 따라 상온에서의 전기 전도도는 증가 했으나 보다 높은 온도에서 activated process에 의한 전기 전도가 일어났고 optical gap과 Hopping parameter $T_o$는 감소했으며 Fermi level의 깊이는 얕아졌다.
이들 data에서 Ni이 들어가면 Fermi level의 localized state가 증가하면 상온에서 전기 전도도가 상승했다는 결론을 얻었다.
이들 시료를 Hydrogenation해주면 전기 전도도는 감소했고 optical gap은 증가했다.
