Deposition of high quality wurtzite GaN films over cubic (111) MgAl2O4 substrates using low pressure metalorganic chemical vapor deposition

Abstract

We report the deposition of high quality single-crystal wurtzite GaN films on cubic (111) spinel (MgAl2O4) substrates. The room-temperature electron mobility and the optically pumped stimulated emission threshold for these films are nearly identical to those of films deposited on basal plane sapphire. Using cross sectional high resolution TEM we have determined the following orientation relationship between the film and the substrate: [0001]GaN//[111]MgAl2O4 and [112̄0]GaN//[110]MgAl2O4. This should provide a common cleavage plane for (111) spinel and the wurtzite GaN films over it.

Microstructure and interface control of GaN/MgAl2O4 grown by metalorganic chemical vapor deposition: Substrate-orientation dependence

“…17,[20][21][22][23] Except for our previous report, 24 few studies have systematically described that the surface evolution is caused by thermal passivation of MgAl 2 O 4 substrates. In addition, the substrate-orientation dependence of the microstructure and interface chemistry of the GaN/MgAl 2 O 4 interface have not yet been investigated.…”

Plasma-assisted molecular-beam epitaxy of ZnO epilayers on atomically flat MgAl2O4(111) substrates

“…8 GaN LD cavities have been obtained by simply cleaving MgAl 2 O 4 substrates along the ͗110͘ direction, 9 which will also work well for ZnO. MgAl 2 O 4 belongs to spinel crystallography (Fd3m).…”

Epitaxial growth of group III-nitride films by pulsed laser deposition and their use in the development of LED devices

“…17, has a small lattice mismatch with group III-nitride films, as listed in Table 1, and is therefore a suitable substrate for epitaxial growth of group III-nitrides [83][84][85]. However, the MgAl 2 O 4 substrate has high partial Mg pressure [83,84].…”

“…17, has a small lattice mismatch with group III-nitride films, as listed in Table 1, and is therefore a suitable substrate for epitaxial growth of group III-nitrides [83][84][85]. However, the MgAl 2 O 4 substrate has high partial Mg pressure [83,84]. If MOCVD or MBE is utilized to grow III-nitride films on MgAl 2 O 4 substrates, intense interfacial reaction will take place due to the diffusion of Mg atoms caused by the high growth temperature [86,87].…”