SUBJECT: Ph.D. Proposal Presentation
BY: Xiayun Zhao
TIME: Wednesday, April 15, 2015, 10:00 a.m.
PLACE: MARC Building, 201
TITLE: Process Measurement and Control for Exposure Controlled Projection Lithography
COMMITTEE: Dr. David W. Rosen, Chair (ME)
Dr. Thomas Kurfess (ME)
Dr. Jun Ueda (ME)
Dr. Martha Grover (ChBE)
Dr. Jerry H. Qi (ME)


The Exposure Controlled Projection Lithography (ECPL) is an additive manufacturing process, which is nonlinear black/grey box and suffering loss of accuracy with existing open-loop process planning methods. To improve the ECPL process accuracy and precision involves with a new research in process modeling, measurement and control. To attain this goal, three research questions will be investigated by this research.
How to develop a real-time metrology based on the existing in-situ interferometric curing monitoring system to measure the cured part dimensions, specifically the cured heights across the curing area?
As a baseline control, without a constitutive process model of first principle differential equations, what is an applicable ECPL process control approach, which could utilize the real-time measurement system to improve the process accuracy?
To further improve the ECPL process accuracy and capacity in 3D microfabrication, considering nonlinear multi physics effects, what is a control-oriented ECPL process dynamics model of differential equations and correspondingly an applicable process control method with the real-time ICM measurement?
The intellectual merit of this research lies in developing real-time measurement and advanced control methods for the ECPL process. The scientific and engineering outcomes from this research will help improve the ECPL process accuracy thereby facilitating its application in micro optics fabrication, and will offer exemplification of applying the methodology of real-time feedback adaptive control for unknown nonlinear process in other additive manufacturing methods.