PMOS에 적합한 Mo 전극의 전기적 화학적 안정성 = Electrical and Chemical Stability of Mo Gate Electrode for PMOS

다국어 초록 (Multilingual Abstract)

In this paper, the properties of Mo as PMOS gate electrodes were studied. The work-function of Mo extracted from C-V characteristic curves was appropriate for PMOS. To identify the electrical and chemical stability of Mo metal gate, the changes of work-function and EOT(Effective Oxide Thickness) values were investigated after 600, 700, 800 and 900℃ RTA(Rapid Thermal Annealing). Also it was found that Mo metal gate was stable up to 900℃ with underlying SiO2 through X-ray diffraction measurement. Sheet resistances of Mo metal gate obtained from 4-point probe were less than 10 Ω/□ that was much lower than those of polysilicon.

국문 초록 (Abstract)

본 논문에서는 Mo을 PMOS의 금속 게이트로 사용하였을 때의 Mo의 특성에 대해서 연구 하였다. Mo을 게이트 물질로 사용한 MOS 커패시터를 제작하였고, 소자의 C-V 특성 곡선으로부터 일함수를 추출하였다. 그 결과 Mo 게이트는 PMOS에 적합한 일함수를 나타내는 것을 알 수 있었다. Mo의 전기적/화학적 안정성을 검증하기 위해서 600, 700, 800 그리고 900℃에서 급속 열처리를 수행하였으며 열처리 이후 유효 산화막의 두께와 일함수의 변화를 살펴보았다. 또한 900℃ 열처리 이후의 XRD 분석을 통해서 Mo 금속 게이트가 SiO2에 대해서 안정하다는 것을 확인하였다. 4점 탐침기로 측정한 Mo 금속 게이트의 면저항은 10 Ω/□ 미만으로 폴리 실리콘에 비해서 매우 작은 값을 나타냈다.

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