• 센서학회지
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• 제6권3호
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• pp.221-227
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• 1997

Pd/NiCr 게이트 MISFET 센서는 변압기 절연유중 용존수소를 감지하기 위해 제조되었다. 센서의 안정성과 고농도 감지성의 향상을 위해 Pd/NiCr 2중 촉매 금속 게이트가 사용되었다. 수소유입에 의한 게이트 전압의 드리프트를 줄이기 위해, 2개의 FET 게이트 절연층을 실리콘 산화막과 실리콘 질화막의 2중 구조로 하였다. Pd/NiCr 게이트 MISFET 센서의 수소 감응 감도는 Pd/Pt 게이트 MISFET 센서의 감도에 비해 약 0.5배이나, 안정성이 좋고, 1000 ppm까지의 고농도까지 측정할 수 있었다.

• 센서학회지
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• 제15권2호
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• pp.90-96
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• 2006

We have fabricated the Pd-blck/NiCr gate MISFET-type $H_2$ sensor to detect the hydrogen in atmosphere. A differential pair-type structure was used to minimize the intrinsic voltage drift of the MISFET. The Pd-black film was deposited in the argon environment by thermal evaporation. In order to eliminate the blister formation in the surface of the hydrogen sensing gate metal, Pd-black/NiCr double metal layer was deposited on the gate insulator. The scanning electron microscopy and the auger electron spectroscopy was used to analyze their surface morphology and basic structure. The Pd-black/NiCr gate MISFET has been shown high sensitivity and stability more than Pd-planar/NiCr gate MISFET.

• 한국수소및신에너지학회논문집
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• 제15권4호
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• pp.317-323
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• 2004

We fabricated a MISFET using Pd/NiCr gate for the detecting of hydrogen gas in the air and investigated its electrical characteristics. To improve stability and high concenntration sensitivity and remove the blister generated by the penetration of hydrogen atoms Pd/NiCr catalyst gate metal are used as dual gate. To reduce the gate drift voltage caused by the inflow of hydrogen, the gate insulators of sensing and reference FFET were constructed with double insulation layers of silicon dioxide and silicon nitride. The hydrogen response of MISFET were amplified with the difference of gate voltages of both MISFET. To minimize the drift and the noise, we used a OP177 operational amplifier. The sensitivity of the Pd/NiCr gate MISFET was lower than that of Pd/Pt gate MISFET, but it showed good stability and ability to detect high concentration hydrogen up to 1000ppm.