A ±0.4°C (3σ) −70 to 200°C time-domain temperature sensor based on heat diffusion in Si and SiO2

Despite the increasing use of ICs at very high temperatures (>;150°C) in automotive and industrial applications, sensing such temperatures is still mostly done with discrete thermocouples or thermistors. This is because conventional integrated temperature sensors are based on BJTs, which have a strongly process-, stress- and temperature-dependent saturation current (I_s). Together with other leakage currents, this leads to rapidly increasing temperature errors at high temperatures: up to ±3.0°C at 200°C [1].