EU PVSEC Programme Online
EU PVSEC 2020, 7 - 11 September 2020
Presentation: 2AO.4.4 Drop Test Method for Impact Loading on Silicon Wafer Edge: Damage and Breakage
Type: Oral
Date: Monday, 7th September 2020
13:30 - 15:00
Author(s): L. Carton, R. Riva, Y. Abidate, F. Coustier, D. Nelias
Presenter / Speaker: L. Carton, CEA, Le Bourget-du-Lac, France
Event: Conference Conference
Session: 2AO.4 Silicon Materials and Defect Engineering
Type(s) of Access:  Conference Registration
Topic: 2. 1 Feedstock, Crystallisation, Wafering, Defect Engineering
Keywords: Silicon Wafer, Fracture Strength, Impact, Damage, Diamond Wire Sawing
Summary / Abstract: While reducing as-cut thickness is a key objective to lower the manufacturing costs, maintaining low breakage rates when processing thinner wafers remains an issue. In this study, we focus on one of the most critical types of stresses experienced by a photovoltaic wafer during handling: impact on edge. We develop and optimize a drop tower setup and experimental protocol, which allows generating an impact on the edge of a monocrystalline diamond-wire sawn as-cut wafer with a known kinetic energy. Impact tests are performed on several hundreds of samples with thickness ranging from 180 to 100 µm. Results show that with decreasing thickness, edge impact is more likely to cause catastrophic failure of the wafer. Four-line bending tests performed on impacted wafers demonstrate that the sensitivity to edge impact is anisotropic. The findings can help provide recommendations on handling technologies applied to DWS silicon wafers.