Umidity dependence of ceramic substrate electroluminescent devices

In order to study the humidity dependence of thin film ceramic substrate electroluminescent devices, two devices were made using thermal evaporation - one with a slightly smaller average grain size in the active layer than the other. The devices were exposed to various levels of relative humidity and were electrically characterized using charge-voltage measurements. It was found that the presence of water in the active layer decreased the leakage resistance of the device while it increased the capacitance of the active layer. The changes observed in the active layer were not fully reversible.