Growth and characterization of Mg-doped GaN and InGaN nanopillar-crystals based on steering-crystal-formed multi-crystalline Si substrates

In our past research, Group-III nitride nanopillar crystals were grown vertically on the multi-crystalline silicon substrate and applied to surface-emitting LEDs. To discuss the further possibilities of this kind of LEDs, such as application in long-wavelength LEDs, Mg-doped GaN and InGaN as important parts of the LEDs were grown under various conditions. Different testing experiments were carried out on these GaN-related samples to clarify their surface morphologies and luminescence characteristics. It was confirmed that Mg was successfully doped into GaN grown on the multi-crystalline silicon substrate. InGaN with a wide range of In-contents was obtained by using the same substrate. It is believed that these materials can be applied to various optoelectronic devices, especially large-area light-emitting devices with emissions of more colors, by analyzing the various properties.