<formula formulatype="inline"><tex Notation="TeX">$1/f$</tex></formula> Noise Model for NPN Bipolar Junction Transistors Based on Radiation Effect

Abstract

Radiation-induced current gain and noise degradations in NPN bipolar junction transistors are due to accumulation of oxide-trapped charges and interface states at the surface of the device. Based on an available model of base surface current of NPN bipolar junction transistors, a simplified model is presented with some approximations at low total dose level, which can explain the degradation mechanisms of the current gain. Based on the theory of carrier number fluctuation and the simplified model of base surface current, a noise model is developed, which can be used to explain the noise degradation induced by the radiation at low total dose level. The model suggests that the gain and noise degradations can be attributed to the same physical origin, and these two kinds of degradations are the result of accumulation of oxide-trapped charges and interface states. The radiations were performed in a source at a dose rate of 10 rad(Si)/s up to a total dose of 70 krad(Si). The degradations of the current gain and noise are compared, and the relationship between noise and the current gain is given, which accords well with the experimental results. Compared to the current gain, the noise parameter is more sensitive, so it may be used to evaluate the radiation resistance capability of bipolar junction transistors.

A bipolar junction transistor EMC modeling method based on physical characteristic measurement and simplex optimization

“…Some researchers have also investigated the impact of total dose, neutron radiation, Co-60 source irradiation, gamma rays, and other nuclear radiation on BJT modeling. [11][12][13][14] Petrosyants et al 15 investigated control methods for test environments under high and low temperatures. The model for predicting the fall time was improved in Vijayalakshmi et al 16 In Wang et al, 17 the impact of composite effects under high temperature and high current on current gain was studied.…”

“…In Barnaby et al, 10 researchers derived a BJT surface recombination current analysis model, which is mainly used to characterize special recombination current effects. Some researchers have also investigated the impact of total dose, neutron radiation, Co‐60 source irradiation, gamma rays, and other nuclear radiation on BJT modeling 11–14 . Petrosyants et al 15 investigated control methods for test environments under high and low temperatures.…”