@inproceedings{6b62964bb8c14339859903f4931b3d44,
title = "Sonic Lift-off of GaAs-based Solar Cells with Reduced Surface Facets",
abstract = "Spalling has been proposed as a promising kerfless technique for slicing thin wafers and devices, enhancing the wafer yield from an ingot by reducing kerf-losses and enabling substrate reuse for the case of costly devices. The main challenge of spalling is to control the roughness and thickness variation of the spalled wafers that can be as high as 100% of the wafer thickness. We have shown previously that the thickness variations are largely influenced by the interaction of the crack front with its own reflected waves. Herein we show that through Sonic Lift-off we can offer a modification to standard spalling technologies that minimizes the interaction of reflected waves with the crack front during lift-off of GaAs(100)-based solar cells. We show that the average surface facets amplitude can be reduced by 96% while obtaining a high quality bulk with no discernible residual strain as measured by PL. The resulting spalling depth can easily be tuned from 100 μm to less than 15μm. The electrical characterization of the Sonic lift-off cell shows no degradation of the VOC and a power conversion within 99% relative of a non-spalled baseline.",
keywords = "Gallium arsenide, lift-off, photovoltaics, spalling",
author = "Coll, {Pablo Guimera} and Anica Neumann and David Smith and Emily Warren and Stephen Polly and Seth Hubbard and Steiner, {Myles A.} and Bertoni, {Mariana I.}",
note = "Funding Information: ACKNOWLEDGEMENT This material is based, in part, upon work supported by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE) under the Solar Energy Technologies Office Award Number DE-EE0008973. The views expressed herein do not necessarily represent the views of the U.S. Department of Energy or the United States Government. Publisher Copyright: {\textcopyright} 2021 IEEE.; 48th IEEE Photovoltaic Specialists Conference, PVSC 2021 ; Conference date: 20-06-2021 Through 25-06-2021",
year = "2021",
month = jun,
day = "20",
doi = "10.1109/PVSC43889.2021.9518656",
language = "English (US)",
series = "Conference Record of the IEEE Photovoltaic Specialists Conference",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
pages = "2141--2143",
booktitle = "2021 IEEE 48th Photovoltaic Specialists Conference, PVSC 2021",
}