Microwave Plasma Enchanced Synthesis Of Nanocrystalline Diamond Films

Diamond thin films are deposited on silicon wafers by MPECVD process with the presence of methane, argon, and hydrogen gases. The reaction chamber is designed with an internal microwave reaction cavity and a high-pressure pocket for improving deposition conditions. Scanning electron microscopy reveals tetrahedral and cauliflower-shaped crystals for polycrystalline diamond and nanocrystalline diamond films, respectively. Spectroscopy ellipsometer studies indicate that diamond-like carbon (DLC) films are deposited with a thickness of 700 nm. Fourier transform infrared spectroscopy shows C-H stretching in the range from 2800 cm -1 to 3000 cm -1 . Nanoindentation is performed on DLC films with an average hardness of 10.98 GPa and an average elastic modulus of 90.32 GPa. The effects of chamber pressure, microwave forward power, and gas mixture on the plasma chemistry are discussed. Substrate temperature has a significant influence on film growth rate, and substrate pretreatment can enhance the quality of diamond films.

Ultrananocrystalline Diamond: Syntheses, Properties, and Applications is a unique practical reference handbook that brings together the basic science of nanoscale carbon structures, particularly its diamond phase, with detailed information on nanodiamond synthesis, properties, and applications. Here you will learn about UNCD in its two forms, as a dispersed powder made by detonation techniques and as a chemical vapor deposited film. You will also learn about the superior mechanical, tribological, transport, electrochemical, and electron emission properties of UNCD for a wide range of applications including MEMS, NEMS, surface acoustic wave (SAW) devices, electrochemical sensors, coatings for field emission arrays, photonic and RF switching, biosensors, and neural prostheses, and more. This ôEverything about Ultra-nanocrystalline Diamondö book with 16 chapters is written by leading experts worldwide. It is for everyone who researches carbon nanostructures, everyone who produces them, everyone who characterizes them, and everyone who builds devices using them.

We are pleased to present the Proceedings of the NATO Advanced Research Workshop “Syntheses, Properties and Applications of Ultrananocrystalline Diamond” which was held June 7-10, 2004 in St. Petersburg, Russia. The main goal of the Workshop was to provide a forum for the intensive exchange of opinions between scientists from Russia and NATO countries in order to give additional impetus to the development of the science and applications of a new carbon nanostructure, called ultrananocrystalline diamond (UNCD) composed of 2-5 nm crystallites. There are two forms of UNCD, dispersed particles and films. The two communities of researchers working on these two forms of UNCD have hitherto lacked a common forum in which to explore areas of scientific and technological overlap. As a consequence, the two fields have up to now developed independently of each other. The time had clearly come to remedy this situation in order to be able to take full advantage of the enormous potential for societal benefits to be derived from exploiting the synergistic relationships between UNCD dispersed particulates and UNCD films. The NATO sponsored ARW therefore occurred in a very timely manner and was successful in beginning the desired dialogue, a precondition for making progress toward the above stated goal. The discovery of UNCD completes a triadof nanostructured carbonswhich includes fullerenes and nanotubes.

ABSTRACT: Diamond is widely known for its extraordinary properties, such as high thermal conductivity, energy bandgap and high material hardness and durability making it a very attractive material for microelectronic and mechanical applications. Synthetic diamonds produced by chemical vapor deposition (CVD) methods retain most of the properties of natural diamond. Within this class of material, nanocrystalline diamond (NCD) is being developed for microelectronic and microelectromechanical systems (MEMS) applications. During this research, intrinsic and doped NCD films were grown by the microwave plasma enhanced chemical vapor deposition (MPECVD) method using CH4/Ar/H2 gas mixture and CH4/Ar/N2 gas chemistries respectively. The first part of research focused on the growth and characterization of NCD films while the second part on the application of NCD as a structural material in MEMS device fabrication.

Three major areas of fundamental research on diamond thin films have been explored during the last period, 1990--1991. A new microwave plasma enhanced laser ablation system has been designed and constructed. This system is currently being used to study the possibility of depositing diamond films on plastic surfaces. A mechanism for nucleating diamond films on single crystal copper surfaces has been proposed and detailed experiments have been carried out. Carbon clusters of C--0 have been successfully used to nucleate diamond on non-diamond surfaces. This invention provides an alternative to using diamond -- grit polish as a nucleating agent.

A comprehensive guide to ultrananocrystalline-diamond (UNCDTM) and thin film technology for implantable and external medical devices, edited by a pioneer in the field. Covering synthesis and properties, clinical applications, and regulation, it is essential reading for researchers and practitioners in materials science and biomedical engineering.