The base current broadening effect and charge separation method of gate-controlled lateral PNP bipolar transistors

Abstract

In order to study the total dose effect and hardness assurance technology for the bipolar devices, we have designed and fabricated different gate-controlled lateral PNP bipolar transistors by various technologies, and preformed 60Co-γ low-dose rate irradiation. The test results show that: 1) Irradiation characteristics of the gate-controlled bipolar transistor are strongly dependent on the fabrication technology, and the passivation layer has a great influence on the irradiation response of the device. The device with a passivation layer will have more interface traps in ionizing radiation environments, and its resistance to ionizing irradiation is greatly weakened. 2) A domestic gated-controlled lateral PNP transistor exhibited a peak current broadening effect at low-dose rate irradiation. In this paper, we analyze the mechanism of the broadening effect, and put forward a new separation method for reducing the base current broadening effect, which not only provides the basis for the design of hardened devices, but also a powerful tool for the study of the enhanced low-dose rate sensitivity of the bipolar device.