Emission characteristics of amorphous silicon field emitter arrays sealed in a vacuum package

Emission characteristics of amorphous silicon field emitter arrays (a-Si FEAs) in a vacuum package sealed with TO-5 have been measured and evaluated. The TO-5 header mounted with a FEA, was inserted through a hole in a glass plate and was hermetically sealed to the glass plate using epoxy resin as a sealant. In the same a-Si FEA device, lower emission currents have been observed in the vacuum package, as compared with those measured in an ultra-high vacuum (UHV) chamber. On the other hand, an a-Si FEA monolithically integrated with a thin-film transistor (TFT) has exhibited almost the same emission characteristics both in the vacuum package and in the UHV chamber at the region of saturated emission currents due to the TFT function. A highly stable emission current of approximately 0.1 μA and with fluctuations of less than 2% has been achieved in the vacuum package at the TFT gate and the extraction voltages of 14 V and 150 V, respectively.