可控转移二维GaSe制备高性能光电探测器

Fabrication of High Performance Photodetectors by the Controllable Transfer of Two-Dimensional GaSe

采用机械剥离法制备二维GaSe纳米材料。光致发光光谱和拉曼光谱证明二维GaSe具有直接带隙,禁带宽度约为2.0 eV,具有较好的结晶质量。通过可控转移技术将二维GaSe放置于两个金属电极上,制成结构简单的光电探测器。光电探测器拥有较快的响应速度(约300 ms)和较高的开关比(约32)。在450 nm波长光照射时,光电探测器的响应度可达144.6 mA/W,外量子效率为39.9%。光电探测器对300 nm紫外光展示了最高的响应能力,响应度为677.2 mA/W,外量子效率为271.2%。缩短两电极间距能有效提升光电探测器的响应度和开关比。上述结果说明,将二维GaSe可控转移到电极上制成光电探测器的工艺流程是可行的,适用于制作高性能二维材料基光电探测器。

2D GaSe nanomaterials were fabricated by the mechanical exfoliation method.The photoluminescence and Raman spectra show that the 2D GaSe has a direct bandgap of 2.O eV and good crystal quality.The 2D GaSe was placed on two metal electrodes to make the photodetector with a simple structure via the controllable transfer.The device shows a fast response of 300 ms and a high on-off ratio of 32.Under the illumination of 450 nm light,the responsivity and external quantum efficiency of the photodetector are 144.6 mA/W and 39.9%respectively.The photodetector has the highest responsivity and external quantum efficiency of 677.2 mA/W and 271.2%respectively at 300 nm UV light.Reducing the spacing between the two electrodes can effectively improve the responsivity and on-off ratio of the photodetector.The above results indicate that the process of transferring the 2D GaSe controllably onto the electrodes to fabricate photodetectors is feasible and suitable for the fabrication of high-performance 2D material-based photodetectors.