In-Situ Self-Compensated PT-ITO Thin Film Strain Gage with a Nanolaminated Structure

This paper reports a novel temperature compensation method for high temperature strain gages by a sophisticated structure design. Nano Pt-ITO thin film strain gages with a nanolaminated structure adherent to the alumina substrate were fabricated by a general micro fabrication process. The temperature coefficient of resistance (TCR) and piezoresistive response of the thin film strain gage have been evaluated up to 1200 °C. It can be found that the nanolaminated thin film had a small TCR of +30 ppm/°C at 1200 °C, which can be attributed to the effective temperature self-compensating effect. In addition, the Pt-ITO thin film had a big gage factor K of 10, which implied a high accuracy for the stain measurement at high temperature.