Recent Advances in High-Growth Rate Single-Crystal CVD Diamond

Journal Article · Thu Jan 01 04:00:00 EST 2009 · Diamond and Related Materials

DOI:https://doi.org/10.1016/j.diamond.2008.12.002· OSTI ID:1019615

Liang, Q; Yan, C; Meng, Y; Lai, J; Krasnicki, S; Mao, H; Hemley, R

There have been important advances in microwave plasma chemical vapor deposition (MPCVD) of large single-crystal CVD diamond at high growth rates and applications of this diamond. The types of gas chemistry and growth conditions, including microwave power, pressure, and substrate surface temperatures, have been varied to optimize diamond quality and growth rates. The diamond has been characterized by a variety of spectroscopic and diffraction techniques. We have grown single-crystal CVD diamond over ten carats and above 1 cm in thickness at growth rates of 50-100 {micro}m/h. Colorless and near colorless single crystals up to two carats have been produced by further optimizing the process. The nominal Vickers fracture toughness of this high-growth rate diamond can be tuned to exceed 20 MPa m{sup 1/2} in comparison to 5-10 MPa m{sup 1/2} for conventional natural and CVD diamond. Post-growth high-pressure/high-temperature (HPHT) and low-pressure/high-temperature (LPHT) annealing have been carried out to alter the optical, mechanical, and electronic properties. Most recently, single-crystal CVD diamond has been successfully annealed by LPHT methods without graphitization up to 2200 C and < 300 Torr for periods of time ranging from a fraction of minute to a few hours. Significant changes observed in UV, visible, infrared, and photoluminescence spectra are attributed to changes in various vacancy centers and extended defects.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: DOE - OFFICE OF SCIENCE
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1019615
• Report Number(s): BNL--95460-2011-JA
• Journal Information: Diamond and Related Materials, Journal Name: Diamond and Related Materials Journal Issue: 5-8 Vol. 18; ISSN 0925-9635
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
CHEMICAL VAPOR DEPOSITION
CHEMISTRY
DEFECTS
DIAMONDS
DIFFRACTION
FRACTURE PROPERTIES
GRAPHITIZATION
MONOCRYSTALS
PHOTOLUMINESCENCE
PLASMA
SPECTRA
SUBSTRATES
THICKNESS
national synchrotron light source