Field emission from carbon nanosheets on pyramidal Si(100)

摘要

Carbon nanosheets were synthesized on pyramidal Si(100) substrates without any catalyst in a microwave plasma-enhanced chemical vapour deposition process. The average length and the growth time of carbon nanosheets were measured to be approx 300 nm and 10 min, equivalent to a growth rate of approx 30 nm min~(-1). By replacing flat Si(100) with pyramidal Si(100) as the substrate, the field emission performance of carbon nanosheets was greatly improved. A low turn-on field of 3.2 V mu m~(-1) and a high current density of 2.5 mA cm~(-2) at 7.0 V mu m~(-1), close to those of carbon nanotube emitters, were achieved. The improvement in field emission was attributed primarily to the pyramidal shape.