Comparison of Relaxation Process of Compressive and Tensile Strains in InGaAs Lattice-Mismatched Layers on InP Substrates

Abstract

This paper investigates the difference in crystal quality between strained-layer multiple quantum wells with compressive (+0.5%) and tensile strains (-0.5 %). For the compressive strain, the photoluminescence intensity decreased and the length of fringe bending increased from 250 Å to 500 Å when the number of periods increased from 5 to 15. The amount of fringe bending increased when the InP thickness decreased, especially when the strain was compressive. We also investigated the relaxation process in an InGaAs layer as a function of the layer thickness (from 25 nm to 2 µ m). For a compressive strain (+1.1%), misfit dislocations were observed near the interface between InGaAs and InP substrate. On the other hand, for a tensile strain (-1.1 %), we observed cracks instead of misfit dislocations. Moreover, the cracks were considered to increase the X-ray full width at half maximum of both the InGaAs lattice-mismatched layer and the InP substrate.

Formation mechanism of a microscale domain and effect on transport properties in strainedVO2thin films onTiO2(001)

“…In the typical case, as reported in InGaAs/InP [20,21] and PrBa 2 Cu3O 7−x /SrTiO 3 [22], the dislocation density decreases with increase film thickness. This trend is opposite in the VO 2 thin films on TiO 2 (001) as shown in Fig.…”

“…We found that domain size decreased with increasing film thickness and that the domain boundary contained cracks and dislocations. The dislocation density increased with increasing film thickness, as the domain size decreased, showing a different tendency from that in other systems [20][21][22]. These dislocations formed from the release of strain energy caused by a phase transformation from tetragonal to monoclinic against the pinning tetragonal layer near the interface.…”

“…4. Dislocations are often produced upon the release of stress, which can be generated by a misfit between lattice constants of the film and substrate as well as differences between their thermal expansion coefficients [20][21][22]…”

TEM studies of stress relaxation in GaAsN and GaP thin films

“…Strain relaxation by plastic deformation occurs by threading dislocations, dislocations along the substrate-film interface, or by twinning [1][2][3][4][5][6][7][8][9]. Relaxation by cracking is commonly observed in highly strained heterostructures [8][9][10][11][12][13][14][15][16]. The relaxation of purely elastic stresses leads to the development of surface undulation [8,9,[17][18][19][20][21][22].…”

(111)-Oriented Gallium Arsenide Tensile-Strained Quantum Dots Tailored for Entangled Photon Emission

“…Regardless, some additional mechanism that is dependent on surface-orientation likely exists that alters or in relation to . Tensile strain is predicted to have a higher barrier to dislocation nucleation, yet lower strain accumulation [81], [82], consistent with the early strain relaxation that occurs with VW growth.…”