Poly Si/Ni(Pt) thin film resistance temperature sensors on GaAs

Ni and Pt resistance temperature sensors on GaAs with an interfacial poly Si thin film as a diffusion barrier were prepared and analyzed. An optimal thickness of the poly Si interfacial barrier layer was investigated in relation to the sensor thermal sensitivity and stability. High thermal performance and stability of the temperature sensors were obtained and confirmed by preliminary reliability tests at 150/spl deg/C for times up to 250 hours.