Improved Efficiency of Multicolor Light Emitting Devices Based on Short-Wavelength LEDs with Down-Converting Phosphors or Polymers

Period of Performance: 03/26/1999 - 10/31/1999

$70K

Phase 1 SBIR

Recipient Firm

Emcore Corp.
394 Elizabeth Ave.
Somerset, NJ 08873
Principal Investigator

Research Topics

Abstract

The development of high brightness LEDs based on the (AlInGa)N materials systems has led to the possibility of revolutionary new approaches to lighting and display fabrication. For the first time, this material system permits the fabrication of efficient UV solid state sources that can be coupled to phosphors for saturated visible color and white light generation. While the operation efficiency of these UV-LED sources can be high, the total lumen output is limited because typical LED operation is in the milliwatt regime. Conventional LED fabrication technologies lead to applications requiring hundreds if not thousands of LED chips to produce high lumen output. This proposal will explore the development of advanced UV-LED designs for operation at high current (power) operation for high lumen output. This will be accomplished by developing alternate growth technology on thick GaN/sapphire substrates which can be thinned to remove the sapphire, thus improving thermal management and light extraction for high efficiency, high lumen output.