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High‐Efficiency Solar Cells Grown on Spalled Germanium for Substrate Reuse without Polishing

Journal Article · · Advanced Energy Materials

Abstract

Radical reduction of III–V device costs requires a multifaceted approach attacking both growth and substrate costs. Implementing device removal and substrate reuse provides an opportunity for substrate cost reduction. Controlled spalling allows removal of thin devices from the expensive substrate; however, the fracture‐based process currently generates surfaces with significant morphological changes compared to polished wafers. 49 single junction devices are fabricated across the spalled surface of full 50 mm germanium wafers without chemo‐mechanical polishing before epitaxial growth. Device defects are identified and related to morphological spalling defects—arrest lines, gull wings, and river lines—and their impact on cell performance using physical and functional characterization techniques. River line defects have the most consistent and detrimental effect on cell performance. Devices achieve a single junction efficiency above 23% and open‐circuit voltage of 1.01 V, demonstrating that spalled germanium does not need to be returned to a pristine, polished state to achieve high‐quality device performance.

Sponsoring Organization:
USDOE
Grant/Contract Number:
AC36-08GO28308
OSTI ID:
1872652
Journal Information:
Advanced Energy Materials, Journal Name: Advanced Energy Materials Journal Issue: 29 Vol. 12; ISSN 1614-6832
Publisher:
Wiley Blackwell (John Wiley & Sons)Copyright Statement
Country of Publication:
Germany
Language:
English

References (29)

Non-Destructive Wafer Recycling for Low-Cost Thin-Film Flexible Optoelectronics journal April 2014
Single Crystal Flexible Electronics Enabled by 3D Spalling journal February 2017
Recent Advances in Biointegrated Optoelectronic Devices journal May 2018
Ultralight High-Efficiency Flexible InGaP/(In)GaAs Tandem Solar Cells on Plastic journal December 2012
A Repeatable Epitaxial Lift-Off Process from a Single GaAs Substrate for Low-Cost and High-Efficiency III-V Solar Cells journal July 2014
Techno-economic analysis of three different substrate removal and reuse strategies for III-V solar cells: Techno-economic analysis for III-V solar cells journal May 2016
Solar cell efficiency tables (Version 58)
  • Green, Martin A.; Dunlop, Ewan D.; Hohl‐Ebinger, Jochen
  • Progress in Photovoltaics: Research and Applications, Vol. 29, Issue 7 https://doi.org/10.1002/pip.3444
journal June 2021
Wafer reuse for repeated growth of III-V solar cells journal May 2010
Impacts of Mode Mixity on Controlled Spalling of (100)-Oriented Germanium journal April 2021
Steady-state cracking in brittle substrates beneath adherent films journal January 1989
Controlled spalling-based mechanical substrate exfoliation for III-V solar cells: A review journal June 2021
Increased fracture depth range in controlled spalling of (100)-oriented germanium via electroplating journal March 2018
The Next Generation of Germanium Substrates: Expoger TM journal January 2017
High rate epitaxial lift-off of InGaP films from GaAs substrates journal April 2000
High-efficiency thin-film InGaP/InGaAs/Ge tandem solar cells enabled by controlled spalling technology journal January 2012
Layer transfer by controlled spalling journal March 2013
The 2020 photovoltaic technologies roadmap journal September 2020
Kerf-Less Removal of Si, Ge, and III–V Layers by Controlled Spalling to Enable Low-Cost PV Technologies journal April 2012
Impact of Threading Dislocations on the Design of GaAs and InGaP/GaAs Solar Cells on Si Using Finite Element Analysis journal January 2013
III–V Solar Cells Grown on Unpolished and Reusable Spalled Ge Substrates journal September 2018
Demonstration of multiple substrate reuses for inverted metamorphic solar cells conference June 2012
Engineering controlled spalling in (100)-oriented GaAs for wafer reuse
  • Sweet, Cassi A.; McNeely, Joshua E.; Gorman, Brian
  • 2015 IEEE 42nd Photovoltaic Specialists Conference (PVSC), 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC) https://doi.org/10.1109/PVSC.2015.7356070
conference June 2015
Recent Progress in Epitaxial Lift-Off Solar Cells
  • Kirk, A. P.; Cardwell, D. W.; Wood, J. D.
  • 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) https://doi.org/10.1109/PVSC.2018.8547801
conference June 2018
GaAs Solar Cells Grown on Unpolished, Spalled Ge Substrates
  • Cavalli, Alessandro; Ley, Brett; Johnston, Steve
  • 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) https://doi.org/10.1109/PVSC.2018.8548112
conference June 2018
Sonic Lift-off of GaAs-based Solar Cells with Reduced Surface Facets conference June 2021
(110)-Oriented GaAs Devices and Spalling as a Platform for Low-Cost III-V Photovoltaics conference June 2021
Imaging characterization techniques applied to Cu(In,Ga)Se2 solar cells
  • Johnston, Steve; Unold, Thomas; Repins, Ingrid
  • Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 28, Issue 4 https://doi.org/10.1116/1.3358303
journal July 2010
High-Efficiency Multijunction Solar Cells journal March 2007
A Techno-Economic Analysis and Cost Reduction Roadmap for III-V Solar Cells report November 2018

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