[1] IMEC, Ctr Microsyst Technol CMST, Technol Pk 15, B-9052 Ghent, Belgium
[2] Univ Ghent, Technol Pk 15, B-9052 Ghent, Belgium
[3] Osaka Univ, Inst Sci & Ind Res, Mihogaoka 8-1, Ibaraki, Osaka 5670047, Japan
[4] Pacific Northwest Natl Lab, POB 999, Richland, WA 99352 USA
[5] Univ Ghent, Dept Mat Sci & Engn, Technol Pk 903, B-9052 Ghent, Belgium