TEMPERATURE AND EXCITATION DEPENDENT PHOTOLUMINESCENCE OF UNDOPED ANDNITROGEN-DOPED ZNSE EPILAYERS

The photoluminescence (PL) properties of ZnSe epitaxial layers grown b y metal-organic vapor phase epitaxy are investigated. A correlation be tween the electron-hole plasma (EHP) band position and the PL intensit y is found and on this basis the nonequilibrium carrier lifetime tau a nd the PL efficiency eta are estimated in the ZnSe layers: tau = 10(-9 ) to 10(-11) s, eta = 0.1 to 0.001%. It is shown that these parameters decrease with decreasing layer thickness and with increasing concentr ation of contaminations and native defects. The influence of the excit ation level and temperature on the intensity and peak position of the band at 472 nm in ZnSe:N and the band at 620 nm in undoped ZnSe epilay ers at 78 K grown at temperatures of T-D > 500 degrees C are studied. It is supposed that these bands are due to recombinations described in the configurational coordinate model.