Self-heating effects on the electrical instability of fully printed p-type organic thin film transistors

Abstract

Bias stress instability has been investigated in printed p-channel organic thin film transistors. The observed instability is related to two mechanisms: one, dominating at low T and causing “mobile ions” like threshold voltage variations is probably due to creation/annihilation of acceptor-like states; the second one, causing charge-trapping like instability, dominates at high T. High drain voltage bias stress experiments, inducing device self-heating, present threshold voltage variations, suggest a channel temperature rise ranging from 50 to 60 °C. The results point out the role of self-heating on the bias-stress instability, which is related to a combination of bias and temperature conditions.

Organic thin film transistors on back molded plastic foil

“…In fact we observe a slight shift of V th (from 0.5 to 0.9 V) and also a minor variation of the mobility while the other parameters and the shape of the electrical characteristics remain almost unchanged. This behavior is consistent with other results in terms of thermal instability [15,17,19] and table 2 summarizes the parameters of the OTFT before and after the injection molding.…”

Facile modification of Cu source–drain (S/D) electrodes for high-performance, low-voltage n-channel organic thin film transistors (OTFTs) based on C 60

“…Remarkably, the mobility degradation is only 46% after stressing for 3600 s, which is much lower than that of unmodified device, suggesting an improved bias stability. The witnessed negative V T shift that opposing the positive gate bias stress in the initial stage of both cases might be caused by the mobile ions located in gate dielectrics, [9,41] which is also responsible for the observed enhancement in I DS owing to the increased charge carrier density in the channel with increased effective gate voltage (V GS -V T ). On the other hand, the followed positive V T shift with prolonged stress time can be due to the electron trapping in the channel region as well as the S/D contact region.…”

Contact Effect in High-Temperature Conjugated Polymer Transistors

“…The distinct behaviors of contact resistance of the two device geometries are unlikely caused by the Joule heating effect at the interface region due to the BCBG device’s high contact resistance. Self-heating in organic transistors can reportedly raise the temperature at the channel from room temperature to up to 60 °C, − but its effect on contact area temperature is barely reported . In these studies, the temperature only increases significantly during a long stressing time at high gate voltage.…”