Thickness dependence of photoluminescence for tensely strained silicon layer on insulator

Strain and crystalline quality of tensely strained silicon on insulator with thickness ranging from 8 to 100 nm have been evaluated by low temperature photoluminescence (PL). The strain conservation in the strained Si layers was checked by Raman spectroscopy. The PL clearly shows the emission related to the strained silicon optical band gap even for strained layers as much as seven times thicker than critical thickness (hc ∼ 15 nm). For very thin layers (9 nm), a 21 meV blueshift is observed in the PL spectra, which corresponds to a 17 meV calculated one coming from quantum confinement in the sSi layer.