Semiconductor Barriers and Process to Improve Quantum Efficiency of Light Emitting Devices

Physical Sciences : Materials and Compounds

Available for non-exclusive licensing


  • Russell Dupuis, Ph.D.
  • Jae Hyun Ryou , Electrical and Computer Engineering
  • Min-Soo Noh, Ph.D. , Electrical and Computer Engineering

Background/unmet need

Quantum wells confine charge carriers to two dimensions, a property that finds applicability in numerous devices. The current technology makes quantum wells by sandwiching a material such as gallium-arsenic-antimony between gallium-arsenide (GaAs), indium-gallium arsenide(InGaAs), aluminum-gallium arsenide (AlGaAs) or some other barriers. These barriers confine the electrons and holes to two different layers (Type II confinement). Consequently, the recombination rate is slow due to the spatial separation of charge carriers. Also, the strain in the current structures is not balanced, and the conduction band offset is not adjusted to a large value.

Invention Description

This invention involves the use of various semiconductor barriers for the confinement of excess carriers to quantum wells composed of alloys of GaAsSb and related materials.

The barriers are chosen to make the band offsets appropriate for carrier confinement. The band alignments of Type I materials are preferred for light emission over Type II. Thus, the material developed in this invention is a significant improvement over other semiconductor materials designed for confinement of charge carriers. We have developed materials for the Type 1 alignment and with appropriate lattice parameters for strain balancing of the quantum wells.


  • Improved radiative recombination rates.
  • Improved quantum efficiency of the light-emitting device
  • Strain in the material is balanced and the conduction band offset is adjusted to a large value.

Market potential/applications

Semiconductor manufacturing, especially FETs; lasers for lightwave communications; optical monitoring; electronics industry

Development Stage

Lab/bench prototype

IP Status

  • 2 foreign patents application filed
  • 1 U.S. patent issued: 6,711,195