Electrical properties and preparation of PLZT thin film by MOCVD using ultrasonic spraying

초음파분무 MOCVD법에 의한 PLZT 박막의 제조 및 전기적 특성

  • 김기현 (경북대학교 무기재료공학과) ;
  • 이진홍 (경북대학교 무기재료공학과) ;
  • 박병옥 (경북대학교 무기재료공학과)
  • Published : 2002.08.01

Abstract

The electrical and optical properties of $(Pb_{0.91}La_{0.09})(Zr_{0.65}Ti_{0.35})O_3$(PLZT) thin films by MOCVD using ultrasonic spraying were investigated. To compensate the Pb loss by evaporation, 5 and 10 wt% of excess Pb was added to 0.2 M precursor. After deposition of films on ITO-coated glasses in oxygen atmosphere for 30 min, films were heated by in-situ RTA (rapid thermal annealing) method. When the films were heat treated at $600^{\circ}C$, perovskite single phase was obtained. The optical property of the film with 10 wt% excess Pb was excellent showing about 84 % of transmittance near 520 nm. The dielectric constant of the film was about 308 and the leakage current of the film was lower than the Pb excess 0, 5 wt% PLZT thin films.

초음파 분무 MOCVD법에 의한 $(Pb_{0.91}La_{0.09})(Zr_{0.65}Ti_{0.35})O_3$(PLZT) 박막의 제조와 광학적, 전기적 특성을 조사하였다. Pb의 휘발성을 고려하여 0.2M의 precursor에 Pb를 5 wt%, 10 wt%과잉 첨가하였다. ITO-coated glass 기판 위에 산소분위기에서 30분 동안 증착한 후 in-situ 상태의 RTA (rapid thermal annealing) 방식으로 열처리를 하였다. 단일 perovskite상의 결정화 온도는 $600^{\circ}C$였다. Pb를 10 wt% 과잉 첨가한 박막의 최대 광투과율은 520nm에서 약 84%로 광학적 특성이 우수하였으며, 유전상수는 약 308의 값을 가졌고, 누설전류는 Pb를 0, 5 wt% 과잉 첨가한 PLZT 박막보다 낮은 값을 가졌다.

Keywords

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