Crystals 186 Diamond Chemical Vapor Deposition

Hwang N.M., Evidence of nanometer-sized charged carbon clusters in the gas phase of the diamond chemical vapor deposition (CVD) process. J. Crystal Growth, 204 (1999) 85-90. 

Boron-doped diamond (BDD) thin films were synthesized at CSEM (Neuchatel, Switzerland) by the hot filament chemical vapor deposition technique (HF CVD) on p-type, low-resistivity (l-3mQcm), single-crystal, silicon wafers (Siltronix). The temperature of the filament was between 2440 and 2560 °C and that of the substrate was monitored at 830 °C. The reactive gas was a mixture of 1% methane in hydrogen, containing trimethylboron as a boron source (1-3 ppm, with respect to H2). The reaction chamber was supplied with the gas mixture at a flow rate of 51 min giving a growth rate of 0.24 pm h for the diamond layer. The obtained diamond film has a thickness of about 1 pm ( 10%) and a resistivity of 15mQcm ( 30%). This HF CVD process produces columnar, random textured, polycrystalline films [9]. 

Battaile, C. C, Srolovitz, D. J., and Butler, J. E., Atomic-scale simulations of chemical vapor deposition on flat and vicinal diamond substrates. 7. Crystal Growth 194, 353-368 (1998). 

K. Hirabayashi, and S. Matsumoto, Flattened diamond crystals synthesized by microwave plasma chemical vapor deposition in a CO-H2 system, J. Appl. Phys., 75(2) 1151-1154 (1994)... 

S. A. Stuart, and S. Prawer, TEM and CBED observation of defects in isolated diamond crystals synthesized by microwave plasma chemical vapor deposition on tungsten wire tips, J. Computer-Assisted Microscopy, 4(2) 201-204 (1992)... 

S. S. Jiang, C. Z. Ge, and N. B. Ming, Morphologic study of (100) single crystal diamond films epitaxially grown by chemical vapor deposition, J. Cryst. Growth, 132(l-2) 200-204 (1993)... 

W. P. Chai, Y. S. Gu, M. Li, Z. H. Mai, Q. Z. Li, L. Yuan, and S. J. Pang, Orientation influence of cubic boron nitride crystal facets on the epitaxial growth of diamond film by microwave plasma chemical vapor deposition, J. Cryst. Growth, 135(3-... 

C. P. Chang, D, L. Flamm, D. E. Ibbotson and J. A. Mucha, Diamond crystal growth by plasma chemical vapor deposition, J. Appl. Phys., 63, 1744-48 (1988). 

For some time, mixtures of H2 and natural gas have been used for chemical vapor deposition (CVD) growth of diamond-like carbon (DEC) films. It is now possible to use this technique to grow diamond seed crystals to produce clear, perfect colorless diamonds. Diamonds grown by the high-pressure methods are invariably doped and thus colored. One company, Apollo, has used the CVD technique to grow 1-ct diamonds. 

Section 1.2 of this Chapter reviews the crystallization of diamond and cubic boron nitride using high pressure, high temperature techniques. Chapter 4 of Part II deals with the subject of chemical vapor deposition of diamond at low pressure. 

Until recently, chemical vapor deposition of cracked hydrocarbons was a source only of pyrolytic carbon with a graphite structure but when deposited in a glow discharge produced by a radio frequency generator of 0.5-1.0 kW from a gas pressure of 0.5-3 kPa and at 950°C, microcrystals of diamond have been deposited. The diamond film is formed from 111 and 100 crystal faces and has a high hardness as shown in Table 6.15. 

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