Comparison between studies of photoluminescence mapping and etching on LEC-InP material. Developing of a non destructive quality control procedure of InP wafers

Different aspects of the structure and morphology of InP were studied in samples cut from S-doped and Zn-doped InP 2'' ingots grown by the LEC technique at Centro Ricerche Venezia in an industrial reactor. The general aim was to compare the quality of different ingots in relation to the growth station configuration. A Fourier Transform Photoluminescence (PL) mapping system and etching techniques were used to reveal morphological details and defects on the wafers. It is demonstrated that PL gives a quick and accurate value of dislocation free area (DFA) and that it can be used for the quality control of commercial wafers.