The Effect Of Patterened Substrate On The Performance Of OFET

In recent decades,organic field effect transistors(OFETs)have attracted widespread attention because of their low cost,light weight,and solution processing.Currently,OFETs have been used in low-power drive circuits,electronic paper,RFID tags,and sensors.However,OFET carrier mobility is still lower compared to silicon-based devices.Therefore,improving the OFET performance becomes critical to the practical application of the OFET.This article mainly studied the effect of patterned substrate on the performance of OFET.First,the process parameters of pre-baking,developing,and etching during the preparation of the patterned substrate are discussed.Secondly,the effects of substrate temperature on the performance of OFET were studied.The pentacene films were deposited at different substrate temperatures.The proper substrate temperature was obtained by comparing the performance of OFETs.Then,the effect of the patterned substrate on the performance of pentacene thin film and OFET was discussed.Using the bottom-gate top-contact structure,OFETs with a groove size of 20?m,25?m and a planar substrate were prepared,respectively,and the performance of the OFET was discussed.Change,and through the AFM topography,the pentacene thin film orientation ratio on a 20?m substrate with a groove size of up to 19%was found,and its mobility was higher than that of an OFET on a substrate with a planar substrate and a groove size of 25 ?m..On the flat substrate,the minimum orientation of pentacene film is only 10%,and the mobility is the lowest.Next,the effect of the source-drain current direction and the direction of the groove(pattern of the patterned substrate)on the performance of the OFET is studied.Through analysis,it was found that when the direction of the source and drain currents is parallel to the direction of the groove,the mobility of the OFET is greater than the mobility of the OFET when the direction of the source and the drain is perpendicular to the direction of the groove,mainly because the carrier transmission path changes when the direction of the source and the drain current changes.The grain boundary barriers that need to be overcome are also different.Finally,the effects of HMDS modified grooved substrates on the performance of OFETs were investigated.It was found that although the grain size of the groove substrate after interface modification was increased,the orientation ratio of the modified film decreased,resulting in the mobility of the OFET being lower than that of the OFET before modification.