ABSTRACT
This chapter deals with the fundamental processes involved in the phosphor materials exhibiting Electroluminescence (EL). The insulating layers play an important role in the stability of the double-insulating layered thin-film EL (TFEL) devices and also control the EL characteristics. The durability of an EL cell depends on the driving conditions and on environmental conditions, especially on temperature and humidity. The electrons are accelerated and excite the luminescence centres similar to the case of high-field EL. There are many phosphor deposition techniques investigated to increase the brightness levels of the EL displays: sputtering method, atomic-layer epitaxy, electron-beam deposition, multisource deposition, metal–organic chemical vapour deposition and low-pressure hydride-transport chemical vapour deposition. In the a.c.-driven TFEL devices, above threshold voltage, one observes a charge transfer whose value increases with increasing voltage.
