Schottky diode temperature sensor for pressure sensor

The small silicon chip of Schottky diode (0.8x0.8x0.4 mm³) with planar arrangement of electrodes (chip PSD) as temperature sensor, which functions under the operating conditions of pressure sensor, was developed. The forward I-V characteristic of chip PSD is determined by potential barrier between Mo and n-Si (N_D = 3 × 10¹⁵ cm^-3). Forward voltage U_F = 208 ± 6 mV and temperature coefficient TC = -1.635 ± 0.015 mV/⁰C (with linearity k_T <0.4% for temperature range of -65 to +85 ⁰C) at supply current I_F = 1 mA is achieved. The reverse I-V characteristic has high breakdown voltage U_BR > 85 V and low leakage current I_L < 5 μA at 25 ⁰C and I_L < 130 μA at 85 ⁰C (U_R = 20 V) because chip PSD contains the structure of two p-type guard rings along the anode perimeter. The application of PSD chip for wider temperature range from -65 to +115 ⁰C is proved. The separate chip PSD of temperature sensor located at a distance of less than 1.5 mm from the pressure sensor chip. The PSD chip transmits input data for temperature compensation of pressure sensor errors by ASIC and for direct temperature measurement.