Theoretical comparison between quantum well and dot infrared photodetectors
The aim of the authors is a performance comparison of quantum dot infrared photodetectors (QDIPs) with quantum well infrared photodetectors (QWIPs) under various operating conditions. This type of photodetector is interesting from the point-of-view that QWIPs have numerous advantages over photodetectors based on HgCdTe. From a quantum structure point-of-view, QDIPs have several advantages over QWIPs, especially their wide spectrum range that can be covered, as well as the availability of absorption normal incident light. However, they still have some problems that include high values of dark current and lower values of their responsivity. For these reasons, there is a need to make a theoretical comparison between the two fundamental types of quantum photodetectors. The more interesting parameters of these detectors to achieve this comparison are calculated. These parameters include dark current, photocurrent, responsivity and detectivity. Numerical results show that QDIPs have a lower value for their responsivity and detectivity for the same operating conditions. The aim is to reduce the dark current by adjusting the doping level of these detectors. Moreover, the effect of lateral size and its associated adaptive value can improve the behaviour of the QDIPs that are processed to some extent.
