University of California
at Santa Barbara
Computer and Electrical Engineering Department
MOLECULAR BEAM EPITAXY Inside the chamber, a beam of phosphorus molecules emerges from one of nine separately heated and shuttered ovens, travels through an ultra high (10>-10 torr) vacuum, to Impinge upon a semiconductor substrate. The gallium phosphide is lattice-matched to the substrate; because of the epitaxial method of growth, extreme vertical dimensional control can be maintained, with controllable layer thicknesses less than 10 Angstroms, and doping levels of up to 1020 impurities per cubic centimeter can be achieved.
The researcher is observing reflection high energy electron diffraction which gives information about the topology and microscopic reconstruction of the semiconductor vacuum interface while the layer is actually growing.
University of California
