高场效应迁移率铁电栅二氧化锡薄膜晶体管的研究

Study on Ferroelectric-gate Thin-film Transistor Using Tin Oxide Channel with High Field Effect Mobility

采用溶胶-凝胶法(Sol-Gel)制备了以n型Si为栅极、二氧化锡(SnO2)薄膜为沟道层、(Bi,Nd)4Ti3O12(BNT)薄膜为绝缘层的薄膜晶体管。晶体管呈现出n沟道增强型性能,其开态电流Ion=25μA,场效应迁移率μsat=0.3cm2·V-1·s-1。BNT铁电薄膜的自发极化以及载流子与极化的耦合作用是晶体管具有较大开态电流和较高场效应迁移率的主要原因。

The ferroelectric-gate thin-film transistors with n-type Si and tin oxide （SnO2） as the channel and ferroelectric （Bi,Nd）4Ti3 O12 （BNT） as the gate insulator were fabricated by sol- gel technique. The transistors exhibit n-type transistor characteristics operating in an enhancement-mode with the ＂on＂ current of 25 μA and a field-effect mobility of 0.3 cm2 · V-1 · s-1. The spontaneous polarization of the BNT ferroelectric thin film and the coupling between polarization of BNT and charge carrier of SnO2 are the main reasons for the large ＂on＂ current and high field effect mobility.