| CdSe, a II-VI compound with direct transition, wide-band-gap and high atomic number (48,34), is regarded as a new effective materials for room temperature nuclear radiation detectors and photoconductive devices, and can be used in many fields.There are many different methods of growth CdSe single crystals, but they have some deficiencies. In our study, the technique of the purification of starting materials had been improved : The purification of polycrystalline and growth of CdSe single crystals had be carried on in the same quartz ampoule and starting materials had been transferred into the growth ampoule directly in the last process of purification, which avoided the extra contamination. By improving the technique of the purification and growth of CdSe single crystals, we got CdSe single crystals with high quality: the magnitude of resistivity, IR transmittance, electron trap densities, dislocation densities of the (110) face were about 107?.cm, 50%, 108 cm-3, 104cm-2 respectively and the chemical ratio of Cd:Se was nearly 1. Through better fabricating process, the resolution of CdSe detectors for 59.5KeV line of 241Am ? -ray at room temperature got 40%. The results show that the modified growth technique is a new and promising method for growing highly purity and perfect CdSe single crystals, and by improving the technique of single crystals growth and fabricating process, the resolution of CdSe detectors can be improved further.This work is an important part of the chief scientific and technological subjects sponsored by the Ministry of Education of China. It will be significant not only for the further study of CdSe single crystals but for the practical applications of the crystals.
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