|SUBJECT:||M.S. Thesis Presentation|
|TIME:||Monday, March 28, 2016, 9:30 a.m.|
|PLACE:||MARC Building, 114|
|TITLE:||Measurement and Analysis of of Wire sawing Induced Residual Stress in Photovoltaic Silicon Wafers|
|COMMITTEE:||Dr. Shreyes Melkote, Chair (ME)
Dr. Steven Danyluk (ME)
Dr. Ajeet Rohatgi (ECE)
Silicon (Si) wafers are used in over ninety percent of solar cells and are the most important material for solar cell production today. As Silicon is a very brittle material, breakage during processing is a significant issue leading to lower production yields and also contributes to a large proportion of the overall solar cell manufacturing cost. The manufacturing process of a Si wafer comprises of first a high temperature heating process to produce a Si ingot from polycrystalline Silicon, which is then cut into bricks and subsequently sawn into wafers using a wire saw. These processes create residual stresses both from the thermal gradient induced by solidification and from either the rolling-indenting or scratching-indenting processes caused by the type of wire saw used. The objective of this research is to study silicon wafer residual stress as a result of the typical industry manufacturing processes and by doing so, better understand the mechanical properties that lead to increased fracture.