PbS量子点同质P-N结光电探测器

PbS quantum dot P-N homojunction photodetector

PbS胶体量子点因其带隙可调、可溶液加工、吸收系数高等优异特性而广泛应用于光电探测器领域。然而基于光电二极管结构的PbS量子点光电探测器通常会使用不同的材料来制备N型层,从而增加了器件设计和工艺的复杂性,不利于这类光电探测器未来在面阵成像芯片中的应用。为简化制备工艺,提出了一种PbS量子点同质P-N结光电探测器,仅通过一种工艺过程实现了器件P型层和N型层的制备。经测试,探测器对不同入射光强度的探测表现出了良好的线性响应;在0.5 V反向偏压作用下,器件在700 nm处的响应度为0.11 A/W,比探测率为3.41×10^(11) Jones,展现出了其对弱光探测的优异能力。结果表明文中提出的PbS量子点同质PN结光电探测器有助于推动其在面阵成像领域中的发展。

PbS colloidal quantum dots are widely used in the field of photodetectors due to the excellent characteristics including adjustable band gap,solution processable and high absorption coefficient,etc.However,PbS quantum dot photodetectors based on photodiode structure tend to use different materials for the processing of the N-type layer,and thus leading to a much more complexed device design method and fabrication process,which hinders the application of such photodetectors in planar array imaging chips in the future.To simplify the fabrication process,a PbS quantum dot P-N homojunction photodetector is proposed here,in which the P-type and N-type layer are prepared by only one process.Results show that the PbS quantum dot photodetector has a good linear response to different incident intensity.The responsivity of the device is about 0.11 A/W and the specific detectivity is approximately 3.41×10^(11) Jones at 700 nm under the reverse bias voltage of 0.5 V,which indicate the excellent performance of the detector in weak illumination conditions.It can be concluded that the PbS quantum dot P-N homojunction photodetector proposed here can promote its development in the field of planar array imaging and is great helpful to the development of planar array imaging chip techniques based on colloidal quantum dots.