Characterization of residual strain in epitaxial Ge layers grown in sub-100 nm width SiO2 trench arrays

Analysis of anisotropic in-plane strain behavior in condensed Si1−x Ge x fin epitaxial layer using X-ray reciprocal space mapping

“…17) In the case of Si 1−x Ge x or Ge fin layers grown selectively in narrow trench patterns, compressive strains are generated asymmetrically with different values in the directions parallel and perpendicular to the fins. [18][19][20][21] This anisotropic in-plane strain is due to differences in the strain relaxation in the two directions, as caused by the following mechanisms. First, the dislocation gliding slip systems differ in the parallel and perpendicular directions.…”

“…In our previous study, we examined the anisotropic in-plane strain in the fin structure. [18][19][20][21] However, there remains a need for a more systematic study of the factors influencing the asymmetric strain in each of the fin dimensions.…”

Formation of a Ge-rich Si1−x Ge x (x > 0.9) fin epitaxial layer condensed by dry oxidation

“…Recently, materials that have high mismatch with Si are directly grown on narrow Si regions between oxide walls using the aspect ratio trapping (ART) technique [11][12][13][14][15][16][17][18][19]. This technique enables a high-mobility and high-lattice mismatch channel to eliminate most defects in the top region because defects like threading dislocations and stacking faults are trapped by the oxide sidewalls.…”

“…By using the ART method, a Si 1−x Ge x fin layer can be grown with a low defect density in the top region between SiO 2 sidewalls. We already reported that a pure Ge fin layer was directly grown in a narrow trench pattern with a selective epitaxial growth (SEG) process and was measured with reciprocal space mapping (RSM) for the asymmetric strain, exhibiting a maximum compressive strain of 0.72% [17][18][19]. According to the study by Eneman et al [20], the hole mobility of the unstrained Ge p-channel is 35% lower than that of a strained Si channel.…”