• 마이크로전자및패키징학회지
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• 제13권1호통권38호
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• pp.17-22
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• 2006

2단계 스퍼터링으로 강유전 PZT 박막을 형성시켜 유전특성과 전도기구를 조사하였다. 또한 PZT 박막 내의 carrier를 보상해주기위해 도너 불순물을 도핑하였다. 2단계 스퍼터링으로 상온층 두에를 조절하여 누설전류를 $10^{-7}A/cm^2$ order까지 줄일 수 있었다. 전도기구가 bulk-limited의 하나임을 확인하였고 따라서 적정한 도너 불순물을 채택하였다. 도너 불순물을 도핑한 경우 2단계 스퍼터링한 PZT 박막의 누설전류 특성은 $10^{-8}A/cm^2$ order까지 개선되었다.

• 한국재료학회지
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• 제12권1호
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• pp.75-81
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• 2002

The ferroelectric properties of Pb(Zr,Ti)O$_3$[PZT] films degrade when the films with Pt top electrodes are annealed in hydrogen containing environment. This is due to the reduction activity of atomic hydrogen that is generated by the catalytic activity of the Pt top electrode. At the initial stage of hydrogen annealing, oxygen vacancies are formed by the reduction activity of hydrogen mainly at the vicinity of top Pt/PZT interface, resulting in a shift of P-E (polarization-electric field) hysteresis curve toward the negative electric field direction. As the hydrogen annealing time increases, oxygen vacancies are formed inside the PZT film by the inward diffusion of hydrogen ions, as a result, the polarization degrades significantly and the degree of P-E curve shift decreases gradually. The direction and the magnitude of the remnant polarization in the PZT film affect the motion of hydrogen ions which determines the degradation of polarization characteristics and the shift in the P-E hysteresis curve of the PZT capacitor during hydrogen annealing. When the remnant polarization is formed in the PZT film by applying a pre-poling voltage prior to hydrogen annealing, the direction of the P-E curve shift induced by hydrogen annealing is opposite to the polarity of the pre-poling voltage. The hydrogen-induced degradation behavior of the PZT capacitor is also affected by the internal field that has been generated in the PZT film by the charges located at the top interface prior to hydrogen annealing.

• JSTS:Journal of Semiconductor Technology and Science
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• 제5권1호
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• pp.45-51
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• 2005

We have developed surface micromachined Infrared ray (IR) focal plane array (FPA), in which single $SiO_{2}$ layer works as an IR absorbing plate and $Pb(Zr_{0.3}Ti_{0.7})O_{2}$ thin film served as a thermally sensitive material. There are some advantages of applying $SiO_{2}$ layer as an IR absorbing layer. First of all, the $SiO_{2}$ has good IR absorbance within $8{\sim}12{\mu}m$ spectrum range. Measured value showed about 60% absorbance of incident IR spectrum in the range. $SiO_{2}$ layer has another important merit when applied to the top of Pt/PZT/Pt stack because it works also as a supporting membrane. Consequently, the IR absorbing layer forms one body with membrane structure, which simplifies the whole MEMS process and gives robustness Ito the structure.