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In recent years, a series of investigations has been devoted to a possibility of using crystals based on CdTe with addition of magnesium (Mg), selenium (Se), or manganese (Mn) for X and gamma radiation detectors. In the literature there are contradictory data with respect to the segregation of Mg in (Cd,Mg)Te and Se in Cd(Te,Se) and to the possibility of obtaining materials with a homogeneous composition without grains and twins. We have wide technological possibilities of preparing crystals and investigating some of their properties. Thus, we performed crystallizations of (Cd,Mg)Te, Cd(Te,Se), (Cd,Mn)(Te,Se), and (Cd,Mn)Te compounds. The aim of our studies was to check whether any of the investigated materials may be easily obtained by the Low Pressure Bridgman (LPB) method in the form of large, homogeneous, high resistivity single crystals with as few as possible twins, subgrains, and tellurium inclusions. The crystallization processes were performed by using the LPB method. The elements used: Cd, Te, Mn, Mg, and Se were of the highest purity available at that time. In order to obtain reliable conclusions the crystallization processes were carried out under identical technological conditions. The details of our technological method and the results of the investigation of physical properties of the samples are presented below.

The aim of this study is to establish the measured concentration of vanadium actually present in the doped crystals as a function of the vanadium concentration determined on the basis of its amount introduced into our (Cd,Mn)Te and CdTe crystals during the growth process. For (Cd,Mn)Te the expected concentration of vanadium varied from 1014 cm−3 to 1020 cm−3. The measurements were performed using the Secondary Ion Mass Spectrometry (SIMS). The measured results for vanadium concentrations from 1014 cm−3 to 3 × 1018 cm−3 differ from the intended ones by not more than a factor of 2 and exhibit the linear relationship. For concentrations above 3 × 1018 cm−3 the measured vanadium concentrations are lower than the nominal ones by more than a factor of 10.