Figure 4: (a) PL emission from samples A (dashed black curve) and A (Ag) (red line). The inset graph shows the respective optical density. Inset table shows the parameters fitting of the measured PL decay curve of each sample according to the stretched exponential model mentioned above. (b) Hydrogen depth profile by ERD. Black triangles and red circles show the hydrogen concentration of samples A and A (Ag), respectively. Ag depth profile (filled gray circle) by RBS and Si depth profile (open gray rhomb) by SRIM simulation are shown for comparison.