Microwave Plasma Enhanced Chemical Vapor Deposition of Diamond in Vapor of Methanol-Based Liquid Solutions

摘要

A method for depositing diamond crystals and diamond films from methanol-based liquid solutions is reported. Liquid solutions are prepared by mixing methanol with other carbon containing liquid compounds which contain a greater than one ratio of carbon to oxygen such as acetone, ethanol, and iso- propanol. An electrical discharge is generated by microwave power in a metal cavity in order to dissociate the vapor mixture from one of the liquid solutions, from which radicals such as OH, O, and H that etch non-diamond carbon much faster than diamond, as well as carbon containing radicals such as CH3 are produced on and near a substrate surface. Graphitic, amorphous and other forms of non-diamond carbon deposits are either suppressed from being deposited on the substrate or preferentially etched by OH, O, and H radicals resulting in the deposition of high quality diamond crystals and diamond films without the need for compressed gases such as hydrogen and methane.