Introduction to CVD Diamond

Introduction to CVD Diamond

Key Equipment for CVD Diamond Growth
CVD reactors are critical for diamond synthesis, with temperature control and heating methods being paramount. Main CVD systems include:

lHot Filament CVD (HFCVD)

lPlasma-Enhanced CVD (PECVD):

  ·Microwave Plasma CVD (MPCVD)

·DC Arc Plasma Jet CVD

lCombustion Flame CVD

Growth Mechanism of CVD Diamond
CVD diamond synthesis involves decomposing carbon-containing precursors (e.g., methane) in a hydrogen-rich reducing atmosphere. Key processes:

lCarbon Source: Methane provides carbon atoms.

lAtomic Hydrogen:

1. Maintains single-bond diamond structure

2. Etches non-diamond carbon phases (graphite/amorphous carbon)

3. Creates surface reactive sites

lGas Mixtures: Methane-hydrogen base, with optional additives (Ar, N₂, O₂) to enhance growth rate/crystal quality.

CVD Process Overview
Chemical Vapor Deposition involves gas-phase and surface reactions. In a standard process:

lSubstrates are exposed to volatile precursors (e.g., CH₄/H₂).

lPrecursors decompose/react on the substrate surface.

lDesired components deposit while byproducts are removed via gas flow.

The CVD diamond synthesis workflow is illustrated in the diagram：