PREPARATION OF LOW RESISTIVE UNINTENTIONALLY DOPED N-TYPE ZNSE

This paper reports on the preparation of low resistive n-type ZnSe bul k material required as substrates for homoepitaxial growth of ZnSe-bas ed devices. ZnSe samples were annealed in molten Zn at temperatures be tween 600 and 950 degrees C for 100 h and subsequently quenched to roo m temperature. Temperature-dependent Hall and conductivity measurement s reveal a maximum carrier concentration of n=1 x 10(17) cm(-3). Mobil ities of up to 550 cm(2) V-1 s(-1) at room temperature were observed. These values are higher than previously reported for Cl-doped ZnSe mol ecular beam epitaxy (MBE) layers. Samples heat-treated under equal con ditions but belonging to crystals of different origin show differences in the achieved free carrier concentration and distinguished photolum inescence spectra. We tentatively discuss the results in terms of impu rity content and quality of used ZnSe crystals. (C) 1997 Elsevier Scie nce S.A.