Liquid-phase epitaxial growth of 6H-SiC by the dipping technique for preparation of blue-light-emitting diodes

Abstract

Epitaxial growth of 6H‐SiC has been carried out at 1500–1650 °C on 6H‐SiC substrates dipped into a Si melt in a graphite crucible. Epitaxial layers up to 100 μm thick have been deposited on the {0001} faces after 5 h growth. Layers grown on the Si faces at 1600 and 1650 °C have fairly flat and smooth surfaces. Undoped layers show n‐type conduction with a typical carrier concentration of 6.3×10¹⁷ cm⁻³ and mobility of 130 cm²/V sec at 300 °K. n‐ and p‐layers of higher carrier concentrations are obtained by the doping of nitrogen and aluminum, respectively. A p‐n junction is prepared in one growth run by an overcompensation procedure. Blue electroluminescence observed under the forward bias has enough brightness under room light at room temperature. The peak wavelength is 485 nm. The external quantum efficiency is 1.0×10⁻⁵ photons/electron at 300 °K.