Argon inclusion in sputtered films and the effect of the gas on molybdenumfield emitter arrays

Residual gas analysis of a number of field emission displays showed that ar gon desorbed from molybdenum metal lines was the dominant gas in sealed vac uum packages. We present experimental results on the emission characteristi cs of molybdenum field emitter arrays in argon ambient. In argon, the emiss ion current dropped rapidly similar to that in oxygenic gas ambients. Exist ing degradation models do not provide an adequate explanation for this beha vior. Rather, we suggest a model based on shallow implantation of argon int o the field emitter tips that increases the effective width of the tunnelin g barrier. Experimental support for this model comes from the following obs ervations: emission current degraded only when the device was turned on; af ter gas exposure, significant current recovery which followed diffusion typ e behavior was noted; degradation and recovery rates were functions of part ial pressure; and no detectable effects associated with sputtering were obs erved. This mechanism is also consistent with ion pumping known to occur in field emission displays. (C) 2001 American Institute of Physics.