The H-In vacancy complex, VInH4, in undoped and Fe-doped liquid encapsulated Czochralski specimens was studied by means of infra-red absorption spectroscopy. The concentration of VInH4 was found to be much lower in wafers which were sliced from the ingot tail. The concentration of VInH4 in Fe-doped material was higher than that in undoped samples. The change in VInH4 concentration of an ingot was in qualitative agreement with a mass action law which was based upon defect reactions. The high VInH4 concentration in the seed-end of an ingot was related to 2 factors. One factor was the high threshold concentrations of Fe and Zn which were required to create semi-insulating and p-type material, respectively. The second factor was that there was a large thermally induced reduction in carrier concentration in seed-end wafers, as compared with wafers from the ingot tail. The results revealed the effect of VInH4 upon thermal stability; which was due to the fact that the bond in the H complex was weak and dissociated easily during annealing. This dissociation was related to the defects which formed in high-temperature annealed material.

H-Vacancy Complex VInH4 Abundance and its Influence in n-Type LEC InP S.Fung, Y.Zhao, N.Sun, C.D.Beling, X.Chen, K.Bi, X.Wu, J.Zhang, T.Sun: Journal of Crystal Growth, 2000, 211[1-4], 174-8