基于等离激元热电子效应的光电晶体管制备及其特性

Fabrication and properties of plasmonic hot-electron phototransistor

为了解决典型宽禁带半导体光电探测器件的工作波段限制材料禁带宽度的问题,对基于表面等离激元热电子效应的光电晶体管进行了制备和光电性能研究,提出一种采用重掺杂的硅片作为背栅极、二氧化硅(SiO_2)氧化层作为绝缘层,且能利用等离激元热电子效应的光电晶体管,有望实现响应光谱的调控。利用热退火方法在绝缘层表面修饰金纳米颗粒,并结合射频溅射、物理掩模和真空热蒸镀的方法实现了热电子效应铟镓锌氧化物(IGZO)光电晶体管。器件的光学和电学性能测试结果表明:修饰金纳米颗粒的光电晶体管在658nm红光入射下产生明显的光电响应,外加90V栅极偏压时,光电流提升约为2.2倍。金纳米颗粒修饰的等离激元热电子结构有效调控了该型晶体管的响应光谱范围,不受材料禁带宽度的限制,而且晶体管的背栅调控进一步放大光电流,提高了器件的量子效率。

Windows of traditional wide band gap photodetectors are limited by the band gap of the semiconducting material used.In order to address this issue,the photoelectric properties of a plasmonic hot-electron phototransistor were fabricated and investigated.We have developed a plasmonic hot-electron phototransistor using a heavily doped silicon wafer as the back gate and insulating layer.Gold nanoparticles(AuNPs)were fabricated on the surface of the insulator via thermal annealing and the plasmonic hot-electron indium gallium zinc oxide(IGZO)phototransistor was developed.We investigated the optical and electrical properties of the phototransistor.The results revealed that the presence of AuNPs increased the photocurrent by a factor of 2.2 under a gate voltage of 90 V as compared to the IGZO phototransistor without AuNPs.The plasmonic hot-electron structure can effectively adjust the spectral response range of the phototransistor.Regulation of the back gate voltage was observed to amplify the photocurrent and improve the quantum efficiency of the device.