Comparison of diamond-like carbon film deposition by electron cyclotron resonance with benzene and methane

Abstract

A comparative study of the deposition of diamond-like carbon films using methane or benzene in a microwave electron cyclotron resonance plasma-enhanced chemical vapor deposition system has been performed. Process variables studied were reactor pressure, applied radio frequency substrate bias, and microwave power. The plasma stream was characterized using optical emission spectroscopy and mass spectrometry. Film properties studied included optical energy gap, total hydrogen content, integrated C-H stretch absorption, index of refraction, and Raman spectra. The use of a high C͞H ratio reactant such as benzene was found to be advantageous over methane in that higher deposition rates were possible and the resultant films exhibit diamond-like properties without the application of large substrate biases. Another result of this investigation was further confirmation that hard carbon films contain a significant quantity of nonbonded hydrogen [A.

Characterization and optical properties of diamondlike carbon prepared by electron cyclotron resonance plasma

“…The visible light absorbance increases monotonically with increasing negative bias voltages, and at negative bias voltages higher than 2100 V, the optical absorbance increases rapidly. 6 are essentially similar to those obtained by Andry et al, 10 Pastel et al, 14 Tamor et al, 25 and Silva et al 26 Unlike other properties, the optical band gap is mainly determined by the states of sp 2 -bonded clusters imbedded in the amorphous carbon medium. 5).…”

“…The deposition rates increase with an increase in the negative bias voltage, reach a maximum at biases of 2(80-100) V, and then decrease at higher negative biasing. 10 Raman peak at around 1550 cm 21 with a shoulder at around 1345 cm 21 , which shows the typical structure characteristic of DLC films. The growth rates of DLC films on PMMA are observably lower than those on Si(111) wafer and glass.…”

“…DLC films are extremely hard, electrically insulating, optically transparent, and have a low friction coefficient, making them attractive candidates for applications such as tribological coatings, 1-3 electronic devices, 3 and infrared optical coatings. 10,11 Recently, a number of studies on DLC deposition by ECR plasma has been reported; in these works a negative substrate bias voltage of more than 2100 V and a microwave power in 50 -200 W were proved to be the conditions favorable for the growth of DLC films with a high sp 3 content. However, in comparison with these techniques, chemical vapor deposition (CVD) using an electron cyclotron resonance (ECR) plasma may be one of the favorable techniques for steady state growth of a-C : H films, since it combines a high plasma density, low substrate temperature, and independent control of ion energy under typical deposition conditions.…”

Structural characteristics of carbon nanorods and nanotubes grown using electron cyclotron resonance chemical vapor deposition

“…On the other hand, other experimental efforts for decreasing the amount of bonded hydrogen caused the same results in the properties of DLC film, including an increase of the substrate temperatures, a usage of source gases with high ratios of C/H, and an addition of Ar gas. [25][26][27] Hydrogen incorporation during the CNT growth, however, has not been considered yet even though the environment for CNT growth is very similar to that for DLC films.…”

Amorphous hydrogenated carbon coatings on IC packaging mold by ECR-CVD system

“…It combines a high plasma density, a low substrate temperature, and using independent control of the ion energy in depositions [12,13]. Many studies of a-C:H depositions by ECR-CVD have been performed [14][15][16][17].…”