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Effects of microwave power on the structural and emission properties of hydrogenated amorphous silicon carbide deposited by electron cyclotron resonance chemical vapor deposition Room temperature luminescence from ( Si/SiO 2 ) n (n=1,2,3) multilayers grown in an industrial low-pressure chemical vapor deposition reactor 100-nm-thick nanocrystalline silicon (nano-Si)-dot multi-layers on a Si substrate were fabricated by the sequential repetition of H-plasma surface treatment, chemical vapor deposition, and surface oxidation, for over 120 times. The diameter of the nano-Si dots was 5-6 nm, as confirmed by both the transmission electron microscopy and X-ray diffraction analysis. The annealing process was important to improve the crystallinity of the nano-Si dot. We investigated quantum confinement effects by Raman spectroscopy and photoluminescence (PL) measurements. Based on the experimental results, we simulated the Raman spectrum using a phenomenological model. Consequently, the strain induced in the nano-Si dots was estimated by comparing the experimental and simulated results. Taking the estimated strain value into consideration, the band gap modulation was measured, and the diameter of the nano-Si dots was calculated to be 5.6 nm by using PL. The relaxation of the q ∼ 0 selection rule model for the nano-Si dots is believed to be important to explain both the phenomena of peak broadening on the low-wavenumber side observed in Raman spectra and the blue shift observed in PL measurements. C 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. [http://dx.

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This study evaluates minority carrier lifetime in floating zone Si affected by advanced and conventional Si IGBT (insulated gate bipolar transistor) processes. Si gate oxidations reduce lifetime due to the formation of interface states between the Si and the oxide. As a result, cross-sectional photoluminescence imaging shows that the lifetime around a trench is lower than that in the bulk region. The high temperature thermal treatment for B-base/P-emitter layer activation after gate oxidation improved the interface, thus resulting in the recovery of the lifetime. TEM observations reveal that the (110) trench surface shows irregular contrast while the (100) surface shows relatively smooth contrast, which is consistent with the lifetime result of “trench side wall surface (100)” > “trench side wall surface (110).” Our study conclusively clarifies that lifetime is correlated with the SiO2 surface state.