Electron irradiation effects on InP-based HEMTs with different gate widths

Abstract

In this paper, the influence of electron irradiation on DC and RF characteristics of InP-based HEMTs with different gate widths were studied by irradiation experiment. The results show that the value of channel current (IDS) and transconductance (gm) are decreased for device with different gate width after electron irradiation, which is mainly due to the reduction of mobility in the channel by the irradiation-induced defects. However, the carrier concentration in the channel has a little change. Compared with the device with 100 μm gate width, IDS and gm of the device with 40 μm gate width were decreased by 1.5% and 3%. Meanwhile, the forward gate current decreased due to the increase of series resistance of gate contact caused by electron irradiation. The interface defects induced by electron irradiation induced the increase of the reverse gate current. Additionally, the current gain cut-off frequency (fT) and maximum oscillation frequency (fmax) were reduced by 19.8% and 10.9% for device with 40 μm gate width, and the fT and fmax were only reduced by 7.1% and 8.2% for device with 100 μm gate width. The experimental results indicate that designing a reasonable structure is an effective method to enhance the radiation resistance in InP-based HEMTs, and this method can also be utilized in other semiconductor devices.