Title
Model-based control of a high-temperature crystal growth process
Abstract
This paper describes a modeling and control approach for the thermal aspects of a high-temperature semiconductor crystal growth process. From a thermal perspective, each crystal growth cycle is composed of three distinct phases, heat up, growth, and cool down, each with specific control challenges and objectives. This paper focuses on the heat up and growth phases. A simulation model is first developed based on the induction furnace geometry and known material properties. This model is calibrated using the experimental process data by minimizing the weighted error between the predicted and actual temperature measurements. The two critical temperatures for the process are the temperature of the source material and the temperature of the crystal seed. For the heat up phase, the input profile is generated to rapidly ramp up the source and crystal temperature while avoiding damaging temperature spikes. In the crystal growth phase, the objective is to maintain the source temperature above sublimation while keeping the crystal temperature sufficiently low to allow condensation. These temperatures cannot be directly measured. Instead, an observer-based controller achieves the temperature control objective. Simulation results with FEM-in-the-loop validation are presented.
Year
DOI
Venue
2008
10.1109/COASE.2008.4626546
Arlington, VA
Keywords
Field
DocType
crystal growth,finite element analysis,high-temperature superconductors,semiconductor growth,sublimation,superconducting transition temperature,temperature control,FEM-in-the-loop validation,crystal temperature,high-temperature semiconductor crystal growth process,induction furnace geometry,model-based control,observer-based controller,temperature measurements,temperature spikes,thermal aspects
Crystal growth,Control theory,Condensation,Mechanical engineering,Sublimation (phase transition),Temperature control,Process variable,Mechanics,Temperature measurement,Materials science,Material properties
Conference
ISSN
ISBN
Citations 
2161-8070
978-1-4244-2023-0
0
PageRank 
References 
Authors
0.34
2
4
Name
Order
Citations
PageRank
Wason, J.100.34
Gressick, W.200.34
Wen, J.T.300.34
Morgan, K.400.34