Automated Hall profiling system for the characterisation of semiconductors at room and liquid nitrogen temperatures

An automated Hall profiling system is described which enables the carrier concentration and mobility profiles of semiconductor layers to be obtained at both room and liquid nitrogen temperatures. The system uses chemical stripping of the layers and the differential Hall effect technique. As many semiconductor devices operate at 77 K, valuable information on the electrical properties of the material at this temperature can be obtained. Typical examples of this are presented for both the III-V and II-VI compound semiconductor systems.