Indium tin oxide spreading layers for AlGaInP visible LEDs

Abstract

In this paper the effectiveness of indium tin oxide (ITO) is assessed as a current spreading layer (CSL) for AlGaInP visible light emitting diodes (LEDs). A range of device structures has been fabricated in order to test the CSL characteristics. As a basis for this comparison test devices have been fabricated both with and without any ITO spreading layers and for comparison with an alternative GaP spreading layer. These measurements confirm that ITO is an effective alternative to the GaP structure with greater potential for applications in low-cost LED arrays.