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The evolution of ionizing radiation-induced defects in gated lateral p-n-p (GLPNP) bipolar transistors at different temperatures is investigated. The experimental results show that when the irradiation dose is less than 25 krad, the change in the reciprocal current gain (Δ (1/β)) increases by increasing the temperature gradually at a given dose. When the dose is more than 25 krad, Δ(1/β) increases first and then decreases at 200 °C by increasing the temperature at a given dose. Gate sweep (GS) technique and deep-level transient spectroscopy (DLTS) analyses show that the positive oxide trapped charges decrease by increasing the temperatures. When the temperature is less than 200 °C, the number of the interface traps gradually increases by increasing the temperature, but when the temperature increases to 200 °C, the number of the interface traps decreases. It indicates that the formation of the positive oxide trapped charges was inhibited at different temperatures above room temperature, and the formation of the interface traps was promoted at less than 200 °C and annealed significantly at 200 °C. Moreover, the change in the number of the interface traps in the transistors induced by the irradiation under different temperatures decides the degradation of the current gain. [ABSTRACT FROM AUTHOR]

Characteristics of displacement defects in the 3CK3637 PNP bipolar junction transistors (BJTs) irradiated by 10 MeV Si, 40 MeV Si and 25 MeV C ions are investigated in this paper. Electrical parameters are measured in-situ using KEITHLEY a 4200-SCS semiconductor characterization system during irradiations. The radiation-induced defects caused by various ions for different displacement damage doses are characterized by deep level transient spectroscopy (DLTS). Experimental results show that the electrical degradation increases with increasing irradiation fluence. It is worth noting that the increase trend of the electrical degradation is different for the three types of ions. For the 10 MeV Si ions, the electrical degradation linearly increases, while, for the 40 MeV Si and 25 MeV C ions, the electrical degradation increases nonlinearly. The change in the reciprocal of current gain (Δ(1/β)) caused by 40 MeV Si and 25 MeV C ions can be normalized in one line at lower displacement damage doses. As the displacement damage dose increases to a certain threshold, the Δ(1/β) deviates from the normalized line. Based on the DLTS analyses, the dominant displacement defects in the 3CK3637 PNP BJTs irradiated by 40 MeV Si and 25 MeV C ions change with increasing displacement dose, leading to the existence of threshold in the electrical degradation curve. [ABSTRACT FROM AUTHOR]