Field emitter arrays (FEAs) are a promising component for novel vacuum micro- and nanoelectronic
devices, such as microwave power amplifiers or fast-switching X-ray sources. However,
the interrelated mechanisms responsible for FEA degradation and failure are not fully understood.
Therefore, we present a measurement method for quantitative observation of individual emission
sites during integral operation using a low-cost, commercially available CMOS imaging sensor.
The emission and degradation behavior of three differently doped FEAs is investigated in currentregulated
operation. The measurements reveal that the limited current of the p-doped emitters leads
to an activation of up to 55% of the individual tips in the array, while the activation of the n-type
FEA stopped at around 30%. This enhanced activation results in a more continuous and uniform
current distribution for the p-type FEA. An analysis of the individual emitter characteristics before
and after a constant current measurement provides novel perspectives on degradation behavior. A
burn-in process that trims the emitting tips to an integral current-specific ideal field enhancement
factor is observed. In this process, blunt tips are sharpened while sharp tips are dulled, resulting in
homogenization within the FEA. The methodology is described in detail, making it easily adaptable
for other groups to apply in the further development of promising FEAs.
«Field emitter arrays (FEAs) are a promising component for novel vacuum micro- and nanoelectronic
devices, such as microwave power amplifiers or fast-switching X-ray sources. However,
the interrelated mechanisms responsible for FEA degradation and failure are not fully understood.
Therefore, we present a measurement method for quantitative observation of individual emission
sites during integral operation using a low-cost, commercially available CMOS imaging sensor.
The emission and deg...
»