MOVPE growth of GaN on Si – Substrates and strain

Response to “Comment on ‘The effects of Si doping on dislocation movement and tensile stress in GaN films’” [J. Appl. Phys. 109, 073509 (2011)]

“…Interestingly, this explains Fig. 9 5 states clearly that we used non-annealed films, with thicknesses confirmed by TEM and SEM. Later, we investigated annealed samples to check for climb-induced dislocation reduction, which did occur.…”

“…2,3 However, in some papers 4,5 "climb" has been used to describe dislocation inclination towards h1 100i during growth, without true dislocation movement. We agree that Si-doping is associated with dislocation inclination in GaN, but find no evidence that it enhances true climb.…”

Internal strains and crystal structure of the layers in AlGaN/GaN heterostructures grown on a sapphire substrate

“…This causes a partial relaxation of elastic deformations and a decreasing value of the Poisson relation compared to the structure without dislocations. 38 On the other hand, the elastic properties of the nanostructures can significantly differ from monocrystals. According to the analysis of Reparaz et al 39 and Pezzoli et al 40 on Ge/Si thin films and quantum dots ͑QDs͒, there is also a great deal of discrepancy between different literature sources regarding the phonon deformation-shift coefficient ͑up to a factor of 2͒.…”

Decoupling of a strained 3C‐SiC(111) thin film on silicon by He+ and O+ ion implantation

“…A prominent example is the effort to grow GaN based thin films on silicon substrates for energy efficient solid state lighting applications [1][2][3][4]. The successful use of Si as a substrate for heteroepitaxial growth depends on the resolution of two fundamental issues: a) the lattice mismatch leading to the formation of undesirable defects like stacking faults or dislocations and b) the large difference in thermal expansion between the silicon substrate and the thin film on top.…”