As the range and scope of thermal imaging and sensing applications expand quantum well infrared photodetectors (QWIPs) are emerging as a new and important technology. The best known and most widely discussed are the n-type devices based on GaAs/AlGaAs. The combined promise of normal incidence detection, a route to integration and the potential for far-infrared ( >20 micron) detection, with Si/SiGe quantum well and quantum dot infrared photodetectors (QDIPS), provides the motivation behind this challenging projects that will develop SiGe epitaxy still further.