Field emission property of hydrogenated chemical vapor deposited diamond films studied by scanning tunneling microscopy.
By using scanning tunneling microscopy, the plots of tunneling current versus applied voltage, at the local points for hydrogenated and oxygenated chemical vapor deposited diamond films, were investigated. For comparison, the measurement points were adopted on the centers of the crystalline grains and at the grain boundaries, respectively. The results indicated that, for the hydrogenated chemical vapor deposited diamond, the field emission character is much better on the center of the crystalline grains than at the grain boundary. In contrast, for the oxygenated samples, the crystalline grains show a poor field emission character. The two diamond surfaces exhibit similar field emission characters at the grain boundaries. The surface emission mechanisms of the hydrogenated chemical vapor deposited diamond films were also discussed.
College of Mechanical and Electrical Engineering, North China University of Technology, Beijing 100144, China.
Fengbin
F
Liu
Jiadao
J
Wang
Darong
D
Chen