Preparation and Characteristics of $CdS_{1-x}Te_{1-x}$ Ternary Polycrystalline Thin Films by Co-evaporation

동시 열증착법에 의한 $CdS_{1-x}Te_{1-x}$ 삼원계 다결정 박막의 제작과 특성

  • 박민서 (대전산업대학교 재료공학과) ;
  • 송복식 (광운대학교 전자재료공학과) ;
  • 정성훈 (광운대학교 전자재료공학과) ;
  • 문동찬 (광운대학교 전자재료공학과) ;
  • 김선태 (대전산업대학교 재료공학과)
  • Published : 1995.11.01

Abstract

$CdS_{1-x}Te_{1-x}$ polycrystalline thin films were fabricated from CdS and CdTe powder by co-evaporation method at $10^{-6}$ Torr. The Optimum evaporation condition was substrate temperature $T_{s}$=$150^{\circ}C$, evaporation time t=30 min. XRD spectrums indicated that the crystal structure chanced from zinc blonde (x$\leq$0.22) to wurtzite (x$\geq$0.96) through mixed structure (0.22$\leq$0.74) as composition value x increase to CdS. Conductive type was n-type by hot point probe method. van der Pauw method was not applicable for x<0,5 due to high hall voltages, Electrical resistivity and Hall carrier mobility were decreased as x increase, while Hall carrier concentration was increased. The optical bandgap of $CdS_{1-x}Te_{1-x}$ polycrystalline thin films measure d at R.T. had quardratic form and the bowing parameter was fitted as 1.98eV for theoretical value of 2.0eV. I-V characteristics of In/CdTe/$CdS_{x}Te_{1-x}$Au Schottky diodes showed that CdS-rich one had better forward characteristics than CdTe-rich one.

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