The Transactions of the Korean Institute of Electrical Engineers C (대한전기학회논문지:전기물성ㆍ응용부문C)

The Korean Institute of Electrical Engineers (대한전기학회)
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A Study on the Reliability of Ru-Zr Metal Gate with Thin Gate Oxide

박막 게이트 산화막에 대한 Ru-Zr 금속 게이트의 신뢰성에 관한 연구

  • 이충근 (한국항공대학교 항공전자공학과) ;
  • 서현상 (한국항공대학교 항공전자공학과) ;
  • 홍신남 (한국항공대학교 전자.정보통신.컴퓨터)
  • Published : 2004.04.01
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Abstract

In this paper, the characteristics of co-sputtered Ru-Zr metal alloy as gate electrode of MOS capacitors have been investigated. The atomic compositions of alloy were varied by using the combinations of relative sputtering power of Ru and .Zr. C-V and I-Vcharacteristics of MOS capacitors were measured to find the effective oxide thickness and work function. The alloy made of about 50% of Ru and 50% of Zr exhibited an adequate work function for nMOS. C-V and I-V measurements after 600 and $700^{\circ}C$ rapid thermal annealing were performed to prove the thermal and chemical stability of the Ru-Zr alloy film. Negligible changes in the accumulated capacitance and work function before and after annealing were observed. Sheet resistance of Ru-Zr alloy was lower than that of poly-silicon. It can be concluded that the Ru-Zr alloy can be a possible substitute for the poly-silicon used as a gate of nMOS.

Keywords

References

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