The Effect of Grain Boundary Diffusion on the Boundary Structure and Electrical Characteristics of Semiconductive $SrTiO_3$ Ceramics

입계확산에 의한 반도성 $SrTiO_3$ 세라믹스의 입계구조 및 전기적 특성 변화

  • 김태균 (인하대학교 무기재료공학과) ;
  • 조남희 (인하대학교 무기재료공학과)
  • Published : 1997.01.01

Abstract

Semiconductive SrTiO3 ceramic bodies were prepared by conventional ceramic powder processes in-cluding sintering in a reducing atmosphere. Sodium or potassium ions were diffused from the surface of the sintered bodies into the inner region using thermal diffusion process at 800-120$0^{\circ}C$. The effects of such ther-mal treatments on the electrical and chemical characteristics of the grain boundaries were investigated. The presence of sodium or potassium ions at grain boundaries produces non-linear current-voltage behaviors, electrical boundary potential barriers of 0.1-0.2eV, and threshold voltages of 10-70V. The diffused ions form diffusion layers with thicknesses of 20-50nm near the grain boundaries, reducing the concentration of strontium and oxygen.

Keywords

$SrTiO_3$;Semiconductive;Potential barrier;Diffusion layer

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