Indium phosphide crystal growth from phosphorus-rich melt

P-rich of InP crystals are rather difficult to achieve, due to the high phosphorus pressure at the melting point. By using the P-injection in-situ synthesis method, there is excessive phosphorus in the melt. In the conditions of M/sub In/ < M/sub In-s/, [P]/sub mol/>[In]/sub mol/, the melt might be P-rich. Since a high thermal stress exists in the LEC growth process with large temperature gradient, it is difficult to release stress, a large number of dislocations come into being around the pores. The pores are distributed in the ingots irregularly. The diameter of the pores is from <0.5 mm to 15 mm on the same wafer. The polished sample wafers with pores were characterized by PL mapping. Dislocations and pores in InP ingots are investigated by means of chemical etching, scanning electron microscopy (SEM). The experimental results show that the cell structures induced by movement and reaction of higher density dislocations exist at the edge of the pores. The EPD around the pores are higher than the other regions and the PL intensities are also inhomogeneous.