Recently, infrared sensors are used various applications including environmental monitoring, military, and medical food industries. Based on the operation principle, previously reported infrared sensor can be divided into photon detectors and thermal ...
Recently, infrared sensors are used various applications including environmental monitoring, military, and medical food industries. Based on the operation principle, previously reported infrared sensor can be divided into photon detectors and thermal detectors. The principle of the photon detector is to convert electrons generated by light into signals. They are fast and sensitive. However, since the operation temperature is low, separate cooling device is required[1,2,3]. In the case of the thermal detector, they need additional process that temperature change via infrared rays and converts it into a signal. In addition, short-wave infrared (SWIR) optoelectronics technology has been used for the structure for quantum well infrared photodetectors (QWIPs) because of the process limitations imposed on integrated devices through complicated processes of forming quantum dots (QDs) based on epitaxial growth methods as well as the requirement of coolers and additional optics for stable operation[4,5,6,7].
In this study, we proposed a high-performance SWIR detection sensor that can operate at room temperature using PbS QDs as a photoactive layer[8,9]. In addition, in order to improve the sensitivity of the SWIR sensor, we adapted the zinc oxide (ZnO) as a interlayer by improving the electron mobility. The proposed PbS QDs SWIR sensor with ZnO nanocrystals shows significantly higher sensitivity and higher stability than the PbS QDs SWIR sensor. The on/off ratio of the PbS QDs SWIR sensor with ZnO is 10 times at –3 V and 33 times at 3 V higher than that of the PbS SWIR sensor without ZnO. In addition, the current stability of the sensor is also improved.