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The interaction mechanism between displacement damage and ionization damage in SiO2 layer has been researched on gate-controlled lateral p-n-p transistor (GLPNP). The sequential irradiation experiments of 400-keV O ions with high dose rate $\gamma $ -rays were carried out, and the degradation and defect evolution results of the device were analyzed by the reciprocal change of current gain change, gate sweep (GS) curve, and deep level transient spectrum (DLTS) results. The results show that there is a negative direct synergistic effect between 400-keV O ions and Co- $60~\gamma $ -rays in GLPNP. At the same time, combined with the GS curve and DLTS results, it can be concluded that the displacement defects of 400-keV O ions in SiO2 layer of GLPNP transistors will capture the holes generated by Co- $60~\gamma $ -rays, thus forming a large number of positive oxide charges ($N_{\mathrm {ot}}$). These $N_{\mathrm {ot}}$ are like “space charge wall,” hindering the movement of protons and holes to the Si/SiO2 interface, and thus inhibiting the generation of interface trap ($N_{\mathrm {it}}$). Due to the decrease of $N_{\mathrm {it}}$ and the increase of positive $N_{\mathrm {ot}}$ , the damage of transistor is weakened. The experimental results show the effects of displacement damage on the ionization effect in SiO2 layer and, more important, provide direct evidence for the space charge model. [ABSTRACT FROM AUTHOR]

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]