Effects of Total Ionizing Dose on Bipolar Junction Transistor

Abstract

Problem statement:The amount of ionizing radiation that Bipolar Junction Transistor (BJT) devices encounter during their lifecycle degrades both of their functional and electrical parameter performances. The different radiation environments either in space, high energy physics experiments, nuclear environment or fabrication process as well as for standard terrestrial operation possess an impact on the devices. Approach: In this research, analytical studies of the effects of ionizing radiation introduced in Commercial-Off-The Shelf (COTS) NPN BJTs by 60 Co gamma (γ) rays had been performed. Results: It was observed that exposure of BJTs to 60 Co caused ionizing radiation damage. Ionizing radiation damage was caused mainly by excess charges trapped on or near the surfaces of their insulating layers and interfaces. This phenomenon reduced the minority carrier lifetime and thus, leading to a decrease in the current gain of the BJTs. Conclusion: This ionizing radiation effect was found to arouse either a permanent or temporarily damage in the devices depending on their current drives and also the Total Ionizing Dose (TID) absorbed. The performance and degradation of selected BJT devices during irradiation with respect to total dose 60 Co were presented in this study.

Gamma Ray Effect on Op-Amp 741 and Timer 555 Ic

“…Thus, the generated holes drift toward the anode, and the electrons drift toward the cathode in the influence of the internal electric field (Assaf, 2020;Babcock et al, 1995;Walldén, 2014;Claro and Santos, 2009). This effect reduces the minority carrier lifetime and so decreases its performance (Pien et al, 2010). The radiation-induced deterioration of BJT is largely due to two operations: a rise in the net positive charge trapped in the oxide covering the device, and an increase of traps positioned near the Si-SiO 2 interface, with energy levels approaching mid-gap (Baliga, 2010;Montagner et al, 1998).…”

Heuristic Detection of the Most Vulnerable Regions in Electronic Devices for Radiation Survivability

“…In this case, changes are manifested mainly in oxide layers that are present in field effect transistor (FET) and bipolar junction transistor (BJT) devices due to the net positive charge and charge traps left at the oxide interfaces after electrons are carried away by existing electric fields. 5,6 The second main effect of ionizing radiation on electronics is caused by single event effects (SEE), in which a single incoming ion interaction causes a large, detectable ionization due to a current transient. 7,8 In both cases, charge traps are created, reducing the mobility of charge carriers and increasing the leakage current and threshold voltage, resulting in device faults [9][10][11] The charge production and diffusion following interaction of target atoms with energetic radiation are probabilistic, because several variables, such as the incoming energy, angle of incidence, and material properties, will define the degree of ionization.…”