Electrostatical considerations of evaporated CdSe thin film

We produced by way of trial Al-CdSe-Al sandwich type evaporated thin films with CdSe-powder and Al-metal. Vacuum was 5Χ10^<-4> torr and thickness of film was about two micron. And capacity was about 5 PF (Measred frequency range was 50 KHz ～ 50 MHz) and Q was about 250 and tan δ was about 0.04. Aging characteristics were not well enough for instability of CdSe material. After one month, the capacity decreased about 2 PF. This value was nearly equal to a stray capacity which occured in case of CdSe plate type evaporated thin film. Therefore this substance did not fitted for real condenser material but we understood that they had a little electrostatical characteristic.