基于单根TaON纳米带的光晶体管与紫外到近红外响应

用Ta₂O₅ 纳米带模板转化法控制合成TaON纳米带, 典型的纳米带长约0.5 cm, 横截面积40 nm×200 nm~ 400 nm×5600 nm。在SiO₂/Si基片上加工出TaON单根纳米带的场效应晶体管; 该晶体管的电子迁移率和开关比分别为9.53×10 ^-4cm ²/(V·s)和3.4, 在254~850 nm范围内显示良好的光响应。在405 nm (42 mW/cm ²)的光照下, 外加5.0 V的偏压时, 光响应为249 mA/W, 光开关比为11。因此, 该器件具有良好的光探测性, TaON纳米带可作为光电子器件的候选材料。另外, 实验还控制合成出Ta₂O₅@TaON纳米带, 并加工成单根纳米带的场效应晶体管, 虽然相同光照条件下的光响应弱于TaON 纳米带, 但仍算是一种好的光电材料。

Phototransistor Based on Single TaON Nanobelt and Its Photoresponse from Ultraviolet to Near-infrared

TaON nanobelts (NBs) were controllably synthesized by Ta₂O₅ NBs template-conversion method. The typical NBs have cross-sections of 40 nm×200 nm-400 nm×5600 nm, and lengths up to about 0.5 cm. A field effect transistor (FET) based on single TaON NB was fabricated on SiO₂/Si substrate. The electronic mobility and on-off ratio of the nanobelts are 9.53×10 ^-4cm ²/(V·s) and 3.4, respectively. The FET shows good photoresponses from 254 nm to 850 nm. Under irradiation of 405 nm light (42 mW/cm ²), the responsivity is 249 mA/W at a bias of 5.0 V, and the photoswitch current ratio is 11. Therefore, the phototransistor shows a good photodetectivity, and TaON NBs may become good candidates for fabricating optoelectronic devices. Additionally, Ta₂O₅@TaON composite NBs were also synthesized, and a FET based on the single NB was fabricated. Under irradiation of the same light, its photoresponse is weaker than TaON NB, but it is still a good optoelectronic material.