Wafer-Scale Fabricated On-Chip Thermionic Electron Sources Based on a Suspended Y2O3/TiN Filament

On-chip electron emission sources are indispensable for developing miniature and integrated vacuum electronic devices on a chip. Here, a new on-chip electron source based on thermionic electron emission from a suspended Y
₂
O
₃
/TiN filament is reported. These thermionic electron sources are fabricated in batches on silicon wafers by microfabrication technologies. Benefit from the low work function of Y
₂
O
₃
, our on-chip thermionic sources exhibit an emission current of up to 1 mA and an emission density of up to 19.3 A/cm
²
at temperature of just 1990 K, much lower than those of previously-reported on-chip thermionic sources of W and carbon nanomaterials filaments with similar emission performances.