Solution growth of cadmium telluride

Abstract

Cadmium telluride crystal has been grown by solution method from Te-rich (Cdo.3Teo. 7) melt. Ingots having 9mm diameter and length up to 30ram were grown by cooling the melt slowly (l~C/h) under a vertical temperature gradient of about 30~C/cm. As-grown ingots were characterized for optical transmission and resistivity. The middle portion of the ingots exhibited better optical transmission properties. Resistivity (p-type) was found increasing, towards the last-to-grow end, from 103 to 106 Q-cm. Surface barrier type of detectors, made from low resistivity (~_ 104 f~-cm) materials, were found suitable for detection of X-and low energy gamma radiations. In case of high resistivity (_~ 106 f2-cm) detectors, the performance was seen to be affected by polarization.

Solution growth of In-doped CdMnTe crystals by the vertical Bridgman method with the ACRT technique

“…For the as-grown CdMnTe crystal, the DAP peak can be ascribed to indium ions recombining with other shallow acceptors, such as Li and Na [22]. The value of I DAP /I (D 0 , X) is 0.21, relatively low intensity of DAP peak demonstrates that the impurities content in CdMnTe crystal is small, which can be attributed to the self-purification of the solution method [17,24]. According to the previous investigation of our group, the D complex peak is not only ascribed to Cd vacancyrelated defects, but also ascribed to dislocations in CdMnTe [25].…”

Tellurium purification: various techniques and limitations

“…Majority of semiconductor crystal properties prepared by tellurium and cadmium are known to have strong harmful influences by the presence of trace level concentration of residual impurities since they reduce substantially detector efficiency (Sahoo and Srikantiah 1996;Krinitsyni et al 2000). Purification steps of tellurium should minimize not only metallic, but also gaseous and gas-forming impurities.…”