Nova Patents
EP0855751A3

Light emitting diode

Abstract

A hybrid organic-inorganic semiconductor light emitting diode 10 comprises an electroluminescent layer 12, 14 and a photoluminescent layer 20. The electroluminescent layer is an inorganic GaN light emitting diode structure that is electroluminescent in the blue or ultraviolet (uv) region of the electromagnetic spectrum when the device is operated. The photoluminescent layer is a photoluminescent organic thin film such as tris-(8-hydroxyquinoline) Al, Alq3, deposited onto the GaN LED and which has a high photoluminescence efficiency. The uv emission from the electroluminescent region excites the Alq3 which photoluminesces in the green. Such a photoconversion results in a light emitting diode that operates in the green (in the visible range). Other colors such as blue or red may be obtained by appropriately doping the Alq3. Furthermore, other luminescent organics in addition to Alq3 may be used to directly convert the uv or blue to other wavelengths of interest. This provides the benefits of simplicity and ease of fabrication, since a complete redesign of the structure is not necessary to change emission wavelength, and the possibility for making displays by spatially varying the deposition of the emissive layer.

EP0855751A3, drawing sheet 1
Sheet 1 of 1

Term

Term ended

Projected expiry passed 17 December 2017, 8.8 years ago.

  1. Priority
  2. Filed
  3. Published
  4. Projected expiry
  5. Today

1 sheet

  1. Sheet 1