GaN-based LEDs grown on 6-inch diameter Si (111) substrates by MOVPE

Abstract

The issues and challenges of growing GaN-based structures on large area Si substrates have been studied. These include Si slip resulting from large temperature non-uniformities and cracking due to differential thermal expansion. Using an AlN nucleation layer in conjunction with an AlGaN buffer layer for stress management, and together with the interactive use of real time in-situ optical monitoring it was possible to realise flat, crack-free and uniform GaN and LED structures on 6-inch Si (111) substrates. The EL performance of processed LED devices was also studied on-wafer, giving good EL characteristics including a forward bias voltage of ~3.5 V at 20 mA from a 500 μm x 500 μm device.

Dislocation reduction in MOVPE grown GaN layers on (111)Si using SiNxand AlGaN layers

“…The potential cost reduction by successful growth of GaN based LEDs on large diameter (111) oriented silicon substrates is thought to give solid state lighting a boost towards replacing incandescent lighting [1]. However, in order to achieve this, a few obstacles still have to be overcome.…”

Characteristics and applications of InGaN micro-light emitting diodes on Si substrates

“…Growth of InGaN LED material on Si substrates has the potential to substantially reduce the cost of device fabrication [9], [10], including the cost of µLED fabrication. However, until now there have not been any reports of µLED devices fabricated on Si substrates.…”

Correlation on GaN epilayer quality and strain in GaN-based LEDs grown on 4-in. Si(1 1 1) substrate

“…In order to overcome this limitation, growth of LEDs on highly conducting 4-to l2-inch silicon (Si) substrates has been suggested as one of the most effective concepts in recent years. In addition, the potential cost reduction by successful growth of GaN-based LEDs on the larger Si substrates is considered to give solid state lighting a boost towards replacing incandescent light [3]. Moreover, choosing Si substrate can also offer numerous advantages, such as good thermal conductivity, simplicity in processing, and possibility of the integration of Si electronics on the same chip [4].…”