Entirely different surface reaction mechanisms (that is, with different surface and bulk
phases and species, and different surface reactions) can be specified in the same
Surface Kinetics input file through the use of multiple materials. For
multiphase chemistry, a material may contain liquid phase components. Both solids and liquid
phase components can be included in the same material. At the beginning of each separate portion
of the input file corresponding to a given material, you give an input line with the keyword
MATERIAL followed by an optional space-delimited material name. If no name
for the material is supplied, a default name MATERIAL
n is provided, where n is the number of the material
(for example, MATERIAL2 for the second material given in an input file). An
example of the usage of multiple materials is given in Figure 4.1: Examples of Material Declarations
.
Figure 4.1: Examples of Material Declarations
!---------------------GAS-PHASE KINETICS PRE-PROCESSOR INPUT------------------
ELEMENTS SI CL E AL
SPECIES E CL2+ CL+ SICL4 SICL2 CL
NOTE THAT ABOVE IS A CHEM.INP FILE, WHILE BELOW IS A SURF.INP FILE.
!---------------------------SURFACE KINETICS PRE-PROCESSOR INPUT--------------
MATERIAL WAFER
SITE/POLY/ SDEN/2.25e-9/
SI(S) SICL(S) SICL2(S) SICL3(S)
END
BULK SI(B)/2.33/
REACTIONS MWOFF
CL + SI(S) => SICL(S) 1.0 0.0 0.0
STICK
E + CL2+ + 2SI(S) => 2SICL(S) 0.4 0.0 0.0
BOHM
E + CL+ + SICL3(S) + SI(B) => SICL4 + SI(S) 0.50 0.0 0.0
BOHM
ENRGDEP/1. 0.5 1.0/ UNITS/EVOLT/
E + CL+ + #SICL3(S) + #SI(B) + SICL(S) &
=> SICL2(S) + #SICL2 + #SICL(S) 0.50 0.0 0.0
BOHM
YIELD/0.0712 1.21 0.5 1.0/ UNITS/EVOLT/
! /A Eth[eV] a b / for #=A(Ei^a-Eth^a)^b
END
MATERIAL WALL
SITE/METAL/ SDEN/2.25E-9/
AL(S) ALCL(S)
END
REACTIONS MWOFF
CL+ + E => CL 0.6 0.0 0.0
BOHM
CL + AL(S) => ALCL(S) 1.0 0.0 0.0
STICK
END