Nanowire Transistor Behavior Under AC Drives

Reliable nanowire transistors (NWTs) under ac drives are required for applications such as display pixels and driving circuits. In this study, the transistor characteristics of SnO
₂
NWTs by ac stress and the effects of passivation were examined to investigate the device reliability under ac drives. Under ac stress, the shift in the threshold voltage (V
_th
) of the devices without passivation was within the range of 2-7 V, whereas the device with passivation showed positive shifts of less than ~1.6 V. The device with passivation also stabilized twice as fast as that without passivation. Heat was generated in the nanowires under ac drives, and accordingly, a passivation layer limited the temperature increase and distributed the carriers more evenly in the nanowires as compared to the nonpassivated case. These mechanisms enable the transistor characteristics to remain stable under ac drives. The stabilization was verified by simulating with a V
_th
model equation for metal oxide semiconductor devices and by including the temperature as a variable. The results show that NWTs with passivation exhibited stable transistor characteristics under repetitive ac stress for long durations. This research suggests improvement measures for fabricating nanowire circuits that are reliable under ac drives.