Stresses in strained GeSi stripes: Calculation and determination from Raman measurements

摘要: Three mechanisms by which edges induce stress relaxation in GeSi strained stripes are described and their relative importance is discussed. Relaxation of stresses the middle layers with l/h(=half-width/thickness) varying from 3 to 100 calculated including effect two important this range. The values manner agree our recent finite element calculations. Since orthogonal directions not equal since usually grown [110] direction on a (100) substrate, determination strain using Raman measurements straightforward. A relation between shifts \ensuremath{\Delta}${\mathrm{\ensuremath{\omega}}}_{3}$ LO frequency strains stripe established. With help relation, single measurement sufficient determine all top layer stripe. Using recently measured known phonon deformation potentials, ${\mathrm{Ge}}_{0.14}$${\mathrm{Si}}_{0.86}$ determined. determined within uncertainty available potentials. method developed general can be used for other semiconductor irrespective whether thermal or due lattice mismatch.