Electron spin resonance and transmission electron microscopy studies of solution-grown CdTe thin films

The electron spin resonance (ESR) and transmission electron microscopy (TEM) of as-grown and air heat treated CdTe thin films deposited by the solution growth method are studied. A single isotropic ESR absorption line at g=2.0002 attributed to Cd+ (I=0) is obtained on heating the films in air at and above 300 °C. Line intensity increases from 300 °C and reaches maximum at 500 °C beyond which it decreases. Electron diffraction studies of the as-grown CdTe films showed the presence of both the zinc blende and the wurtzite phases, whereas those of the films heated in air showed only the zinc blende phase but along with additional phases: TeO2 (observed at 300 °C) and CdTeO3 (observed at 550 °C).