The effect of InGaN/GaN MQW hydrogen treatment and threading dislocation optimization on GaN LED efficiency

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • RAS - Ioffe Physico Technical Institute
  • Optogan Oy

Abstract

We report on the effect of GaN buffer threading dislocation (TD) optimization and InGaN/GaN quantum well (QW) hydrogen (H2) treatment on the efficiency of GaN light emitting diodes (LEDs) operating in the spectral range from 400 to 500 nm. A tenfold reduction of the TD density in the GaN buffer increased the efficiency of blue LEDs operating at high current density, while in green LEDs it had very little effect. The reduced TD density also increased the compressive strain in the InGaN QWs, and caused blue shift to the electroluminescence (EL) peak wavelength. The H2 treatment of the QWs increased strain inside the MQW stack. It was possible to apply the H2 treatment only to UV LEDs, as the increased strain in blue and green LEDs caused relaxation of the MQW stack. Although this resulted in smooth surface morphology of the MQW stack, it did not lead to any increase in the efficiency of the UV LEDs.

Details

Original languageEnglish
Pages (from-to)740-743
Number of pages4
JournalJournal of Crystal Growth
Volume298
Publication statusPublished - Jan 2007
MoE publication typeA1 Journal article-refereed

    Research areas

  • A3. Metalorganic chemical vapor deposition, B1. InGaN, B1. Quantum wells, B3. Light-emitting diodes

ID: 4220165