Defect evaluation by photoluminescence for uniaxially strained Si-On-insulator

Uniaxial strain was introduced to Si-on-insulator (SOI) substrate by SiN deposition using electron cyclotron resonance sputtering combined with lift-off technique. The gate-opening surface with the uniaxial strain was passivated by SiO₂ films, followed by optional thermal treatments. Strain-relaxation was observed by Raman spectroscopy for the thermally-treated samples. Photoluminescence (PL) was used to evaluate defects generated during strain-relaxation. Defect-related PL signal was observed for the thermally-treated strained channel. The intensity of defect signal positively depends on thermal treatment temperature and SiN thickness. Defect generation was investigated during strain relaxation.