Dependence of the accuracy of the silicon diode temperature sensors for cryogenic thermometry on the spread of their parameters

Experimental samples of silicon diode temperature sensors for cryogenic thermometry are prepared. The process spread and variability of these diode temperature sensors and their effect on the parameters of these diode temperature sensors are studied. In particular, it was found that the spread of the base region doping level in the samples did not exceed 20%, the thickness spread of the base region is 3.5%. The measurement accuracy is highly dependent on the ideality factor spread: at room temperature and when the operating current is 1 μA, 1% change in the value of the ideality factor leads to a measurement error of ± 0.35 °C and a change of 10% leads to a measurement error of ± 3.6 °C.