Effects of Vacuum Annealing on the Optical Properties of Sputtered Vanadium Oxide Thin Films

스퍼터된 바나듐 산화막의 광학적 특성에 미치는 진공 어닐링의 효과

  • 이승철 (공주대학교 정보통신공학부) ;
  • 황인수 (공주대학교 정보통신공학부) ;
  • 최복길 (공주대학교 정보통신공학부) ;
  • 최창규 (서울산업대학교 전기공학과) ;
  • 김성진 (경남대학교 전기전자공학부)
  • Published : 2003.07.10

Abstract

Thin films of vanadium oxide(VOx) have been deposited by r.f. magnetron sputtering from $V_2O_5$ target in gas mixture of argon and oxygen. The oxygen/(oxygen+argon) partial pressure ratio of 0% and 8% is adopted. Crystal structure and optical properties of films sputter-deposited under different oxygen gas pressures and in situ annealed in vacuum at $400^{\circ}C$ for 1h and 4h are characterized through XRD and optical absorption measurements. The films as-deposited are amorphous, but $0%O_2$ films annealed for time longer than 4h and $8%O_2$ films annealed for time longer than 1h are polycrystalline. The optical transmission of the films annealed in vacuum decreases considerably than the as-deposited films and the optical absorption of all the films increases rapidly at wavelength shorter than about 550nm. Indirect and direct optical band gaps were decreased with increasing the annealing time.

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