Skip to Content
Find More Like This
Return to Search

Producing Low-cost Lattice-matched Substrates Through Methods of Single Crystal Exfoliation

National Renewable Energy Laboratory

Contact NREL About This Technology

Technology Marketing Summary

Ultra-efficient III-V multijunction solar cells are finding increasing viability in many of today’s advanced electrical devices. For instance, due to their light weight, high-efficiency, and flexible architecture, multijunction III-V cells are attractive for use in weight-, space-, power-, or design-constrained systems like orbital technologies, unmanned aerial vehicles, electric vehicles, man- and vehicle-portable power systems, and even in concentrated photovoltaic devices where extreme physical space limitations may apply. Despite their many advantages, III-V multijunction cells remain relatively expensive and efforts are underway at NREL and elsewhere to both reduce cost or further improve efficiency to make III-V multijunction cells more affordable on a $/Watt basis.

Description

A significant barrier to widespread deployment of III-V photovoltaic devices is the expense of reusing the high-quality single-crystal substrate layers upon which III-V material layers are epitaxially grown.  Substrate reuse procedures require extensive preparatory steps including etch-release and/or chemical mechanical polishing to maintain an effective growth surface over multiple reuses and thereby incur considerable costs to the overall production of epitaxially-grown devices. To work around this obstacle, researchers at NREL and the Colorado School of Mines have developed processes for generating wholly new and inexpensive crystal substrates by mechanically exfoliating (removing) them from single bulk crystals. The resulting near-atomically flat 2D surface templates may be lattice-matched to III-V materials and enable significantly more substrate reuses than current techniques – thereby distributing the cost of the growth substrate over a larger number of epitaxially-grown devices. By eliminating the expensive traditional manufacturing steps of substrate surface re-preparation with a simpler alternative, such exfoliation processes have high potential to significantly lower the production costs for epitaxially-grown III-V devices, including multijunction photovoltaic cells.

Benefits
  • Cost reduction of large-area single crystal substrates
  • Enhanced capability for widescale production and deployment of III-V multijunction photovoltaics
Applications and Industries
  • Aerospace
  • Aviation
  • Solar concentration applications
More Information
Technology Status
Technology IDDevelopment StageAvailabilityPublishedLast Updated
ROI 17-14PrototypeAvailable06/28/201806/28/2018

Contact NREL About This Technology

To: Bill Hadley<Bill.Hadley@nrel.gov>