Extraordinarily Weak Temperature Dependence of the Drain Current in Small-Molecule Schottky-Contact-Controlled Transistors through Active-Layer and Contact Interplay
Extraordinarily Weak Temperature Dependence of the Drain Current in Small-Molecule Schottky-Contact-Controlled Transistors through Active-Layer and Contact Interplay
复制标题
通过有源层和接触相互作用，小分子肖特基接触控制晶体管中漏极电流的温度依赖性极弱
DOI：
10.1002/aelm.202201163
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发表时间：
2022
影响因子：
6.2
通讯作者：
Bestelink E
中科院分区：
文献类型：
--
作者：
Bestelink E
采用交错器件结构的触控薄膜晶体管（TFTs）可以实现低饱和电压和极高的固有增益，这是通过在源触点处引入能量势垒实现的。由此产生的器件，源门控晶体管（SGT），由于源能势垒引起的漏极电流的高温依赖性，其实用性受到限制。本文利用了源触点的热特性和半导体之间的相互作用，以显示基于有机半导体（osgt）的sgt对温度的依赖性大大降低。无论源能垒的高度如何，漏极电流的温度依赖性都非常弱（在34 K范围内，使用Ti触点的osgt为27.8%，而使用Au触点的osgt为22.1%）。半导体迁移率的降低抵消了源处载流子热离子场发射的增加。这对sgt来说是第一次，并为消除其广泛采用的最后障碍之一提供了一条途径。具有Ti触点的osgt也表现出：极低漏极源电压下的漏极电流饱和（饱和系数为0.22）；70天后稳定性显著；漏极电流随通道长度或光照变化最小。
Low saturation voltages and extremely high intrinsic gain can be achieved in contact‐controlled thin‐film transistors (TFTs) with staggered device architecture, enabled by the energy barrier introduced at the source contact. The resulting device, the source‐gated transistor (SGT), is limited in its usefulness by the high temperature dependence of the drain current induced by the source energy barrier. Here, the interaction between the thermal characteristics of the source contact and the semiconductor to show drastically reduced temperature dependence for SGTs based on organic semiconductors (OSGTs) is exploited. This extraordinarily weak temperature dependence of the drain current is observed regardless of the height of the source energy barrier (27.8% in OSGTs with Ti contacts compared to 22.1% when using Au contacts, over a 34 K range). The reduction in mobility of the semiconductor offsets an increase in thermionic‐field emission of charge carriers at the source. This is a first for SGTs and provides a route to removing one of the last hurdles to their wider adoption. The OSGTs with Ti contacts also demonstrate: drain‐current saturation at very low drain‐source voltages (saturation factor of 0.22); noteworthy stability after 70 days; and minimal drain‐current variation with channel length or illumination.