Vandervelde Thomas E, Krishna Sanjay
Department of Electrical and Computer Engineering, Tufts University, Medford, MA 02115, USA.
J Nanosci Nanotechnol. 2010 Mar;10(3):1450-60. doi: 10.1166/jnn.2010.2028.
Over the past fifteen years, there has been significant interest in developing intersubband quantum dot (QD) detectors for the mid-(MWIR) and long-wave infrared (LWIR) regimes. This class of detectors is generally referred to as quantum dot infrared photodetectors, or QDIPs. At present, one of the leading technologies is that of the quantum dots-in-a-well infrared photodetector, called a DWELL-IP or just a DWELL detector. The DWELL name comes from the active region's structure, which consists of a layer of quantum dots imbedded in (or in some cases grown on) a quantum well. This dot/well combination is similarly surrounded by a barrier material. Here, we identify the major players and their contributions to the evolution of the DWELL-IP. While this dot/well/barrier material combination originally consisted of InAs/InGaAs/GaAs, the materials used has widened in recent years. This paper reviews the progress to date for this quickly advancing field. Some of these advancements have come from the additional focus that has been brought to bear on the physical understanding and experimental mechanics of the structure itself. Explorations into the multi-spectral nature of these detectors have also created unique applications for these detectors. This type of QDIP is now becoming the dominant detector of its class and is quickly heading for parity with quantum well infrared photodetectors (QWIPs) that are presently commercially dominant. Given the potential utility of the infrared spectrum for applications in medicine, military, industrial, and academic fields the DWELL-IPs potential to be an inexpensive, versatile, multi-spectral, infrared detector indicates it has a bright future.
在过去的十五年里，人们对开发用于中波红外（MWIR）和长波红外（LWIR）波段的子带间量子点（QD）探测器产生了浓厚兴趣。这类探测器通常被称为量子点红外光电探测器，即QDIP。目前，领先技术之一是阱中量子点红外光电探测器，称为DWELL-IP或简称为DWELL探测器。DWELL这个名字源于有源区的结构，它由嵌入（或在某些情况下生长在）量子阱中的一层量子点组成。这种点/阱组合同样被一种势垒材料包围。在这里，我们确定了主要参与者及其对DWELL-IP发展的贡献。虽然这种点/阱/势垒材料组合最初由InAs/InGaAs/GaAs组成，但近年来使用的材料范围已经扩大。本文回顾了这个快速发展领域迄今为止的进展。其中一些进展来自于对该结构本身的物理理解和实验机制的更多关注。对这些探测器多光谱特性的探索也为它们创造了独特的应用。这种类型的QDIP现在正成为同类探测器中的主导探测器，并迅速朝着与目前在商业上占主导地位的量子阱红外光电探测器（QWIP）相媲美的方向发展。鉴于红外光谱在医学、军事、工业和学术领域应用的潜在效用，DWELL-IP作为一种廉价、通用、多光谱的红外探测器的潜力表明它有着光明的未来。
