Modulation and Refinement of In–N re-Bonding of InGaN Through in Post-Flow During a Refined Temper Fire Treatment Process

Abstract

In this article, we describe a subtle method for modulating and refining the indium-nitrogen (In-N) re-bonding effect of InGaN by employing an In post-flow during temper fire (ΔT = 110°C) treatment. After optimizing the In flow rate and the temper fire treatment process, the In content in InGaN quantum wells (QWs) increased from 12.7 to 22.3% and the (102) epitaxy quality of InGaN improved, as revealed by the full-width at half-maximum (FWHM) of the X-ray diffractometry signal decreasing from 410 to 374 arcsec. In addition, the quality of a five InGaN/GaN multiple-QW epilayer surface also improved greatly when applying this technique. Merely by modulating the In post-flow rate (0, 5.6, 11.2, 16.8, 22.4, or 28.0 μmol/min), the InxGa1-xN photoluminescence signal (and FWHM) changed from 449 nm (58 nm) in the absence of In post-flow during the temper fire treatment process, to 523 nm (46 nm) when the In post-flow rate was 11.2 μmol/min, and to 534 nm (55 nm) when the In post-flow rate was 28.0 μmol/min. This technique is, therefore, effective at improving the InGaN quality and compensating for the In-N bond desorption rate.

Keywords

• GaN
• InGaN-based green LEDs
• Indium–nitrogen re-bonding
• refinement
• metal–organic vapor phase epitaxy