“…From the results of DLTS, three samples, labeled Fe100, Fe1000, and Fe10,000, had the Fe-related trap concentrations of B1 Â 10 14 , 9Â 10 14 , and 3Â 10 13 cm À3 , respectively. An electrochemical etching [17] was proceeded to form PS layer on the Fe-contaminated Si substrate in the solution of HF:H 2 O:C 2 H 5 OH (1:1:2) under the illumination of halogen lamp with 250 W. The anodization current density was a 60 mA/cm 2 and the etching time was 5 min for all Fe-contaminated Si substrates. The reference PS sample was also prepared through the same process except for only the Fe contamination.…”