AIXTRON CRIUS II - CVD (Chemical Vapor Deposition); Description; Process Technology

crius_II_en_00, Edition 06/2010
56 CONFIDENTIAL AIXTRON - Dokumentation
Description System Manual
Process technology CRIUS II
3
3.1 Process technology
CVD (Chemical Vapour Deposition) is a common method for deposition of thin
films.
3.1.1 CVD (Chemical Vapor Deposition)
In a CVD process, volatile compounds are transported into the reactor cham-
ber via the gas phase. Here they are decomposed on a hot substrate by ther-
mal energy.
The following reaction steps take place (see Fig. 3-1,  56):
1 Transport of the reagents in the gas phase to the substrate, e.g. by
means of a carrier gas
2 Diffusion of the molecules through the phase interface gas/boundary
layer
3 Adsorption on the substrate surface
4 Migration of the molecules to crystallization zones
5 Chemical decomposition
6 Desorption of the by-products and diffusion and convection out from the
boundary layer
7 Transport of the by-products out from the reactor
Fig. 3-1 CVD reaction steps
A Gas phase
B Boundary layer
C Substrate
A
B
C
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