Journal of the Institute of Electronics Engineers of Korea SD (대한전자공학회논문지SD)

The Institute of Electronics and Information Engineers (대한전자공학회)
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A Study on the Reason of the Changes of MILC Poly-Si TFT's Characteristics by Electrical Stress

전기적 스트레스에 의한 MILC poly-Si TFT 특성변화 원인에 관한 연구

  • Kim, Gi-Bum (School of Materials Science and Engineering, Seoul National University) ;
  • Kim, Tae-Kyung (School of Materials Science and Engineering, Seoul National University) ;
  • Lee, Byung-Il (School of Materials Science and Engineering, Seoul National University) ;
  • Joo, Seung-Ki (School of Materials Science and Engineering, Seoul National University)
  • Published : 2000.12.01
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Abstract

The effects of electrical stress on MILC(Metal Induced Lateral Crystallization) poly-Si TFT were studied. After the electrical stress was applied on the TFT’s which were fabricated by MILC process, off-state(VG<0V) current was reduced by $10^2{\sim}10^4$ times. However, when the device on which electrical stress was applied was annealed in furnace, the off-state current increased as annealing temperature increased. From the dependence of off-state current on the post-annealing temperature, activation energy of the trap states in MILC poly-Si thin films was calculated to be 0.34eV.

금속유도 측면 결정화에 의해 제작된 다결정 실리콘 박막 트랜지스터(Thin Film Transistor; TFT)의 전기적 스트레스의 효과에 대해 연구하였다. MILC로 제작된 TFT에 전기적 스트레스가 인가될 때, off-state 전류가 100배에서 10000배까지 감소한다. 그러나 전기적 스트레스를 인가한 소자를 관상로에서 열처리를 할 경우 열처리온도가 증가할 수록 off-state 전류가 다시 증가했다. 열처리온도에 따른 off-state 전류의 의존성으로부터 MILC 다결정 실리콘 박막내 트랩준위의 활성화에너지(0.34eV)를 얻어냈다.

Keywords

References

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