Field emission characteristics of COSi2/TaN-coated silicon emitter tips

Abstract

This work has improved the emission characteristics of Si emitter tips by coating a CoSi2/TaN bilayer on the tips. The CoSi2 layer was grown in situ by a reactive chemical-vapor deposition of cyclopentadienyl dicarbonyl cobalt at 650 degreesC. The TaN was then deposited on the CoSi2 layer at 550 degreesC by a reactive sputtering of Ta with N as a reactive gas. The CoSi2/TaN-coated emitters showed a lower turn-on voltage and higher emission current than the CoSi2- or TaN-coated emitters due to the low work function by TaN and the easy transport of electron by CoSi2 with low resistivity. The long-term emission stability of CoSi2/TaN-coated Si emitter was as good as TaN-coated emitter.