Large-area high-quality single crystal diamond
Résumé
Diamond offers a unique combination of extreme physical properties. For many technological applications, diamond samples of the highest crystal quality are required to utilize the ultimate potential of the material. Specifically, grain boundaries, as in polycrystalline films, have to be avoided. In this article, the two major current approaches of synthesizing single crystal diamond by chemical vapor deposition are described. In homoepitaxy, high gas pressure and high power density microwave discharges facilitating growth rates above 50 µm/h form the basis for the deposition of mm-thick single crystal samples. Cloning and tiling followed by homoepitaxial overgrowth are promising novel concepts aimed at an increase in the lateral dimensions. Heteroepitaxial deposition on large-area single crystals of a foreign material represents a second alternative approach. The state of the art for both concepts is summarized, and current as well as potential future applications are discussed.
Mots clés
gas pressure
radiant fluid density
grain boundaries
Physical properties
Microwaves
Vapor deposition
Chemical vapor deposition
Crystal growth
Epitaxy
CHEMICAL-VAPOR-DEPOSITION
HIGH GROWTH-RATE
RATE HOMOEPITAXIAL GROWTH
IRIDIUM BUFFER LAYERS
MICROWAVE PLASMA CVD
HETEROEPITAXIAL DIAMOND
ELECTRON-MICROSCOPY
EPITAXIAL-GROWTH
DOMAIN FORMATION
HIGH-PRESSURE
diamond
single crystal
cloning
discharge