Diamond-Like Amorphous Carbon Films Deposited for Field-Emission Use by Upper-Electrode-RF-Power-Controlled Supermagnetron Plasma

摘要

Nitrogenated and hydrogenated diamond-like amorphous carbon (DAC:N and DAC:H) films were synthesized using i-C_4H_(10)/ (N_2 and H_2) Supermagnetron plasma, respectively. The upper- and lower-electrode rf powers (UPRF/LORF) were controlled to be 100-800/100 W, and N_2 and the H_2 concentrations were selected to be 25 and 20%, respectively. In the DAC:N layer deposited at 300/100 W, the nitrogen atom concentration was measured to be 1.7 mass %. In the case of DAC:N film, the lowest threshold electric field intensity (E_(TH)) was observed to be 12V/μm at the growth condition of 300/100 W. In the case of a DAC:H planar structure, the lowest E_(TH) was 13 V/μm for 800/100 W deposition. In both types in the films with the lowest E_(TH), we observed the same optical band gap of approximately 1.2eV. The optimum distribution and size of sp~2 CC nanoclusters formed in both the DAC layers probably caused the E_(TH) to decrease.