Enhanced Quality Thin Film Cu(In,Ga)Se.sub.2 for Semiconductor Device Applications by Vapor-Phase Recrystallization
U.S. Patent 5,356,839
Technology Description Enhanced quality thin films of Cu.sub.w (In,Ga.sub.y)Se.sub.z for semiconductor device applications are fabricated by initially forming a Cu-rich, phase-separated compound mixture comprising Cu(In,Ga):Cu.sub.x Se on a substrate to form a large-grain precursor and then converting the excess Cu.sub.x Se to Cu(In,Ga)Se.sub.2 by exposing it to an activity of In and/or Ga, either in vapor In and/or Ga form or in solid (In,Ga).sub.y Se.sub.z. Alternatively, the conversion can be made by sequential deposition of In and/or Ga and Se onto the phase-separated precursor. The conversion process is preferably performed in the temperature range of about 300.degree.-600.degree. C., where the Cu(In,Ga)Se.sub.2 remains solid, while the excess Cu.sub.x Se is in a liquid flux. The characteristic of the resulting Cu.sub.w (In,Ga).sub.y Se.sub.z can be controlled by the temperature. Higher temperatures, such as 500.degree.-600.degree. C., result in a nearly stoichiometric Cu(In,Ga)Se.sub.2, whereas lower temperatures, such as 300.degree.-400.degree. C., result in a more Cu-poor compound, such as the Cu.sub.z (In,Ga).sub.4 Se.sub.7 phase.
See the full U.S. Patent for this technology. NREL is looking for an organization to develop and commercialize this innovative technology. Interested organizations may consider developing/commercializing this technology through a license agreement, Cooperative Research Agreement, or Work for Others agreement. Please contact Richard Bolin at (303) 275-3028 for licensing, CRADA, and Work for Others opportunities.
Type of Offer:
« More Solar Patents