Single Photon Detection by Nanowire Phototransistor Formed byColumnar Quantum Dot

利用半导体纳米结构，特别是量子点(QD)和纳米线结构制作了单光子探测器。纳米线结构是通过将量子层与薄的间隔层堆叠而成的。纳米线的直径约为20 nm，而高度可以通过改变层数和厚度来控制，最高可达100 nm左右。通过对包含纳米线的二极管结构的I-V测量，发现纳米线起到了电流传输通道的作用。利用该纳米线电流通道，制备了光电晶体管结构，并对其光学和结构特性进行了研究。

Single photon detectors have been fabricated using semiconductor nanostructures, especially quantum dot (QD) and nanowire structures. The nanowire structure was formed by stacking the QD layers with thin spacer layers. The diameter of the nanowire was approximately 20 nm, while the height can be controlled by varying the number of layers and the thickness, up to about 100 nm. From I-V measurement of the diode structure which includes the nanowire, it was found that the nanowire act as the current transport channel. Using this nanowire current channel, the phototransistor structure was also fabricated and the optical and structural properties were studied.