Heterojunction for Multi-Junction Solar Cells

Technology Summary

Sandia National Laboratories has created a semiconductor p-n heterojunction for use in forming a photodetector that has applications for use in a multi-junction solar cell and detecting light at an energy greater than 0.95-1.2 eV.


This semiconductor is made up of a layer of indium gallium arsenide nitride (InGaAsN) with n-type doping that is epitaxially grown in contact with a layer of gallium arsenide (GaAs) with p-type doping.  The InGaAsN/ GaAs semiconductor p-n heterojunction of the present invention can be use in combination with semiconductor p-n homojunctions of conventional design to form an efficient multi-junction solar cell.


  • Forms an efficient 0.95-1.2 eV bandgap pohotodetector for use in a multifunction solar cell
  • Contacting layers of p-type GaAs overcomes the limitation of a low electron diffusion that occurs in homojunctions or heterojunctions formed in part from p-type InGaAsN
  • The n-type InGaAsN and p-type GaAs provide a substanial increase in open-circuit voltage and short-circuit current as compared to homojunctions and heterojunctions formed in part from p-type InGaAsN
  • In space applications, an increased solar cell efficiency is advantageous for increasing the available electrical power or reducing satellite mass and launch cost. 

Applications and Industries

  • Generation of electricity for space photovoltaic applications
  • Terrestrial high-concentration photovoltaic applications

Intellectual Property

ID Number
Patent Number
InGaAsN/GaAs heterojunction for multi-junction solar cells 6376.0 6,252,287 06/26/2001
Technology IDSD#6376Development StagePrototype - Sandia estimates this technology at a Technology Readiness Level 5. Key elements of the technology have been demonstrated in relevant environments.AvailabilityAvailable - Various licensing and partnering options are available. Please contact the Intellectual Property department to discuss. Published09/29/2011Last Updated01/30/2013