Applied Science and Convergence Technology 2006; 15(6): 563-575
Published online November 1, 2006
Copyright © The Korean Vacuum Society.
Jin-Hyo Boo , Cheol Ho Heo , Yong Ki Cho , Joo Sun Yoon , Jeon-G. Han
Ti(C,N) films are synthesized by pulsed DC plasma enhanced chemical vapor deposition (PEMOCVD) using metal-organic compounds of tetrakis diethylamido titanium at 200 - 300 ℃. To compare plasma parameter, in this study, H₂ and He/H₂ gases are used as carrier gas. The effect of N₂ and NH₃ gases as reactive gas is also evaluated in reduction of C content of the films. Radical formation and ionization behaviors in plasma are analyzed in-situ by optical emission spectroscopy (OES) at various pulsed bias voltages and gas species. He and H₂ mixture is very effective in enhancing ionization of radicals, especially for the N₂. Ammonia (NH₃) gas also highly reduces the formation of CN radical, thereby decreasing C content of Ti(C,N) films in a great deal. The microhardness of film is obtained to be 1,250 Hk0.01 to 1,760 Hk0.01 depending on gas species and bias voltage. Higher hardness can be obtained under the conditions of H₂ and N₂ gases as well as bias voltage of 600 V.
Hf(C,N) films were also obtained by pulsed DC PEMOCVD from tetrakis diethylamido hafnium and N₂/He-H₂ mixture. The depositions were carried out at temperature of below 300 ℃, total chamber pressure of 1 Torr and varying the deposition parameters. Influences of the nitrogen contents in the plasma decreased the growth rate and attributed to amorphous components, to the high carbon content of the film. In XRD analysis the domain lattice plain was (111) direction and the maximum microhardness was observed to be 2,460 Hk0.025 for a Hf(C,N) film grown under -600 V and 0.1 flow rate of nitrogen. The optical emission spectra measured during PEMOCVD processes of Hf(C,N) film growth were also discussed. N₂, N₂?, H, He, CH, CN radicals and metal species(Hf) were detected and CH, CN radicals that make an important role of total PEMOCVD process increased carbon content.
Keywords: Ti(C,N)과 Hf(C,N) 코팅막,PEMOCVD,플라즈마 진단분석,OES,미세경도,저온증착,Ti and Hf coating layers,Plasma diagnostics,Microhardness,Low temperature coating process