Department of
Chemical Engineering
An Object-Oriented Modular Simulation Framework for
Semiconductor CVD Processing Systems
Jing Chen, Raymond A. Adomaitis
Objectives
Data
• Design a set of computational tools for solving lumped
and distributed parameter models generated in process
design and simulation
• Develop flexible and reusable modular components for
CVD systems
• Apply the technique of object-oriented design to reduce
developing cycles of designing new systems and lower
costs of CVD process design and simulations
• Facilitate distributed simulation through the application
of Java and XML technique to heterogeneous data
archiving, analysis and presentation
Why OOP and Modular
Case Study -- Programmable CVD System
• Archive data in XML format
• Facilitate distributed simulation
and information sharing
Simulator
input
Ar
Web
applications
Simulator
validation
Process
diagnosis
Simulation of gases composition profile along segment
Approach
• Standalone modules which could
be physical parts or virtual parts
describing transport or reaction
mechanisms
Processes/Applications
• Determine the modules:
• one segment class : describe the transportation inside a segment
• one inter-flux class : describe the diffusion of gases among segment
ALD
PECVD
Other
process
Programmable
CVD
MOCVD
BREAK
DOWN
• Compose the system:
• 3 objects of the segment module
• 1 object of the inter-segment flux module
Gas
Lamp
ShowerHead
Surface
Reaction
Wafer
GasPhase
Reactions
SubHeater
Qik
• Solve the system with non-linear solver
DepRate
Standalone Modules
Framework
Systems
• Specified by users through input
of modularized components
• Acting as a coordinator for
information exchanging
and distribution among
modules in the system
z=L
Nik
Systems
micro
valve
Steady-state
CSTR model of
WCVD
Other userdefined
system
z = zf
Orifice
…...
Conclusions
Modular
components
Relations
• Computational tools include
two main packages:
Solutions
Computational
tools
• Solvers offer different algorithms
for solving AE/ODE/DAE systems
• MWRtools used for discretizing
PDE systems and solving the
systems by weighted residual
methods
MWRtools
DAE
nonlinear
solving
Manager
• The application of OOD and modular approach greatly improves current
modeling and simulation capability
Solvers
ODE
Parser
z=0
wafer surface at z = -h
Energy bal’n
on wafer
Computational Tools
Systems
As
Mass bal’n in
gas phase
Channel
Discretizing
Experimental
data
Property
estimator
Af
W
Data
Physical/
thermal/
kinetics data
Details on the system and modeling equations
can be found in “Spatially Programmable
Chemical Vapor Depostion”
-- Choo, Adomaitis, et.al., 2003
Parameter
identification
Modular Components
WaferTemp
• Modular approach:
• Allow different variable names among modules
• Allow distributed simulation
• May solve modules with different algorithms
• Easy to change model structure
H2
WF6
Distributed
applications
Web
applications
• Include information on properties
of equipment or process and
have subsystem equations
associated with
• Features of OOP:
• Encapsulation
• Inheritance
• Polymorphism
Property
Data
Experimental
Data
• Separates data applications
and presentation
PDE
systems
ODE
AE
DAE
er
nv
co
tin
g
• The development of the object-oriented simulation library offers a set of
flexible and adaptable tools for solving large systems consisting of
different application models
• Modularized components can be easily integrated to form a new CVD
systems. The system can be solved in the sequential or simultaneous
approach depending on the specific applications
• The application of Java and XML technology to wrap and manipulate data
facilitates data distribution among dissimilar applications