Journal of the Korea Institute of Information and Communication Engineering (한국정보통신학회논문지)

The Korea Institute of Information and Commucation Engineering (한국정보통신학회)
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Preparation and Characteristics of PLT(28) Thin Film Using Sol-Gel Method

Sol-Gel 법을 이용한 PLT(28) 박막의 제작과 특성

  • 강성준 (여수대학교 반도체학과) ;
  • 정양희 (여수대학교 전기공학과) ;
  • 류재흥 (여수대학교 컴퓨터공학과)
  • Published : 2005.11.01
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Abstract

We fabricated the $Pb_{0.72}La_{0.28}TiO_3$ (PLT(28)) thin film successfully by using the sol-gel method and characterized it to evaluate its potential for being utilized as the capacitor dielectrics of ULSI DRAMs. In our sol-gel process, the acetates were used as the starting materials. Through the TGA-DTA analysis, we established the excellent fabrication conditions of the sol-gel method for the PLT(28) thin film. We obtained the dense and crack-free PLT(28) thin film of $100\%$ perovskite phase by drying at $350^{\circ}C$ after each coating and final annealing at $650^{\circ}C$. Electrical properties of PLT(28) thin film were measured through formation on the $Pt/Ti/SiO_2/Si$ substrate and its dielectric constant and leakage current density were measured as 936 and $1.1{\mu}A/cm^2$, respectively.

[ $Pb_{0.72}La_{0.28}TiO_3$ ] (PLT(28)) 박막을 sol-gel 법을 이용하여 제작한 후, 그 특성을 조사하여 ULSI DRAM 의 캐패시터 절연막으로서의 적용 가능성을 연구하였다. Sol-gel 법의 출발 물질로는 acetate 계를 사용하였다. TGA-DTA 분석을 통하여 PLT(28) 박막의 sol-gel 법에 의한 공정 조건을 확립하였다. 매 coating 후 $350^{\circ}C$ 에서 drying 하고, 마지막으로 $650^{\circ}C$ 에서 annealing 하여 $100\%$ perovskite 구조를 가지는 치밀하고 crack 이 없는 PLT(28) 박막을 얻었다. $Pt/Ti/SiO_2/Si$ 기판 위에 PLT(28) 박막을 형성하여 전기적 특성을 측정하였다. 그 결과 유전 상수와 누설전류밀도가 각각 936 과 $1.1{\mu}A/cm^2$ 으로 측정되었다.

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References

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