Trace elemental analysis of InP and related process materials by glow-discharge mass-spectrometry (GDMS)

The development of growth technology for undoped or low level Fe-doped indium phosphide (InP) single crystals and epitaxial layers often requires evaluation of residual impurities at concentration levels below 10¹⁵ at/cm³. Glow discharge mass spectrometry (GDMS) is well recognized as an analytical tool for trace impurity analysis in various semiconductors and related process materials. In the recent paper we present various aspects of application of GDMS for the analysis of bulk and epitaxial InP along with process materials. The following subjects are addressed: general description of analytical technique; physical aspects of DC glow-discharge in semi-insulating compound semiconductors; analytical aspects of GDMS in application to InP; a description of the most common trace impurities found in InP and related process materials, and some examples of GDMS application in material science of InP such as a revealing of the longitudinal impurity inhomogeneity in single crystals and elemental depth profile in epitaxial InP