Schottky diode temperature sensor for pressure sensor

Abstract

The small silicon chip of Schottky diode (0.8x0.8x0.4 mm<sup>3</sup>) 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<sub>D</sub> = 3 × 10<sup>15</sup> cm<sup>-3</sup>). Forward voltage U<sub>F</sub> = 208 ± 6 mV and temperature coefficient TC = -1.635 ± 0.015 mV/⁰C (with linearity k<sub>T</sub> <0.4% for temperature range of -65 to +85 ⁰C) at supply current I<sub>F</sub> = 1 mA is achieved. The reverse I-V characteristic has high breakdown voltage U<sub>BR</sub> > 85 V and low leakage current I<sub>L</sub> < 5 μA at 25 ⁰C and I<sub>L</sub> < 130 μA at 85 ⁰C (U<sub>R</sub> = 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.

Pressure Sensor Chip with New Electrical Circuit for 10 kPa Range

“…The sensor assembly allows for measuring differential pressure. All samples were exposed to temperature and pressure cycling to remove residual assembly stress before functional testing [23][24][25][26][27][28].…”

Pressure Sensor with Novel Electrical Circuit Utilizing Bipolar Junction Transistor

“…The sensor assembly allows for measuring differential pressure. All samples were exposed to temperature and pressure cycling to remove residual assembly stress before functional testing [33][34][35][36][37]. Pressure sensors with PDA-NFL chip were compared with similar products utilizing Wheatstone bridge circuit having the same or similar pressure range: 1) mass-fabricated 60 kPa pressure sensor IPD60 (VNIIA), 2) high-sensitivity 5 kPa CBMP sensor (in development) [38,39], 3) ultra-high sensitivity pressure sensor [22,23] mentioned in Introduction.…”