GaN deposition on AlN/Si substrates for FEAs

The GaN epitaxy on Si substrates shaped specifically for field emission arrays (FEAs) has been described. In such applications the substantial thing is to deposit GaN crystals on tops of Si micropyramids or cones. To achieve such a goal an auxiliary layer of AlN has been applied. It is well known that GaN has far better matching of lattice with AlN compared to Si. It appears that GaN prefers to grow on AlN, too. Furthermore AlN and GaN layers can be grown in the same epitaxy process. In this work the MOVPE method was used