Microstructure of gallium nitride films grown on silicon (110)

Abstract

The microstructure of GaN layers grown on Si(110) is studied by transmission electron microscopy. The GaN layers were grown by metal-organic vapor phase epitaxy using low-temperature AlN interlayers and a high-temperature AlN seed layer. Anisotropic misfit strain originating at the AlN/Si(110) interface is notably reflected in the microstructure of the GaN layers. The stress produced in GaN/Si(110) films is relieved by bending of edge type threading dislocations over the basal plane, generating horizontal segments aligned all along the closely lattice matched direction [11¯00]. It is proposed that the horizontal defects are generated by a driven force with glide- and climb-components manifested on some of the prismatic slip planes of GaN. The general mechanism of the change in the propagation direction of dislocations is discussed.

On the anisotropic wafer curvature of GaN-based heterostructures on Si(110) substrates grown by MOVPE

“…Anisotropic strain in GaN films on Si(1 1 0) has recently been reported to result in domains elongated in the m-axis direction [14]. This mechanism of strain-altered adatom mobility may be responsible for the greater roughness of the GaN film in our case.…”

“…Overlap broadening is estimated by fitting Pearson VII functions [16] to the O peaks and adds an additional 70-80 arcsec to both FWHMs. The remaining intrinsic GaN-1 peak FWHM anisotropy is expected to be related to the anisotropic growth process and the formation of elongated GaN domains [14]. Further quantitative analysis was not performed due to strong peak overlap found in symmetric and asymmetric RSM.…”

Microstructural characteristics of AlN thin layers grown on Si(110) substrates by molecular beam epitaxy: Transmission electron microscopy study

“…In particular, nitride-on-silicon structures are considered to be excellent candidates for unique design architectures and for creating devices for high-power applications. Therefore, a great deal of effort has been concentrated on growing compound semiconductors on Si substrates [1][2][3][4][5][6].…”

Microstructural characteristics of GaN/AlN thin films grown on a Si (110) substrate by molecular beam epitaxy: Transmission electron microscopy study

“…In addition, nitride-on-silicon structures afford the possibility of an excellent candidates for unique design architectures and for creating devices for high-power applications. Therefore, much effort has been concentrated on the growth of AlN and GaN layers on Si substrates [5][6][7].…”

“…In addition, nitride-on-silicon structures afford the possibility of an excellent candidates for unique design architectures and for creating devices for high-power applications. Therefore, much effort has been concentrated on the growth of AlN and GaN layers on Si substrates [5][6][7].For the epitaxial growth of nitride thin films, a Si (110) wafer has begun to attract attention as a substrate, due to its interesting interface structure [5,8,9]. When nitrides are grown on a Si (110) substrate, the orientation relationship between the GaN and AlN and the Si is The main purpose of this study was to understand microstructural properties, such as the atomic structure, dislocation distribution, and strain behaviors, of GaN/AlN structures grown on Si (110) substrates.…”