The influence of forming voltage on the ACEL characteristics of ZnS:Mn

Cu powder DCEL devices is investigated.The samples of DCEL device were formed under 100

115

130

145 and 160 volts respectively

and then operated under AC voltage of 50Hz. The operation voltage was risen from 55 to no volts step by step

At each step

the samples were excited simultaneously in the same period for several hundred hours. In the meantime the brightness and current were recorded.The results from experiments are analyzed and the influence of forming voltage on the two most important parameters

that is the initial and the final brightness at different operating voltage is studied.The experimental results show that the order of arrangement of the initial and the final brightness from lower to higher changes regularly with the increased forming voltage and operating voltage. At the lower operating voltage

the lower the forming voltage

the higher the brightness is. With increasing operation voltage

the order of arrangement of the initial and the final brightness is regularly reversed gradually.An interesting and important property is discovecl. This property shows that the state tends to

be identical with increasing AC operation voltage for DCEL samples formed under various DC voltage. It also means that the higher the AC operation voltage

the less the influence of forming voltage on ACEL characteristics of DCEL devices is. For this reason

the difference in ACEL for samples formed under different voltage decreases with the increase of operation voltage and at last the ACEL characteristics tend to be the same. The phenomenon is considered that Cu

+

migration happens under AC operation

which is just like that under DC operation.