The field emission characteristics of a field emitter array (FEA) with a new resistive layer structure both before and after annealing processes was measured. The gate voltage for emission current of 10 nA per tip increased from 70 to 93 V. The drastic changes in the field emission characteristics of a Mo-tip FEA with PH3-doped a-Si:H after a vacuum packaging process is attributed to the increase in the resistivity of the resistive layer. From the results of elastic recoil detection, secondary ion mass spectrometry, Raman spectroscopy, the increase in the resistivity of PH3-doped hydrogenated amorphous silicon is assumed to be related to the evolution of hydrogen in the thin film. Taken into consideration the fact that the hydrogen evolution occurs at 300–400 °C, the increase in the resistivity of PH3-doped a-Si:H is inevitable if typical frit glass would be used for the hermetic sealing. The resistive layer material with a constant resistivity through all the processes in the field emission display would be desirable. But, if the resistivity would change a lot during the processes, as in the case of doped hydrogenated amorphous silicon, the resistive layer should be designed to target the value after the vacuum packaging processes. © 2002 American Vacuum Society.