(19)

(11)

EP 2 160 766 A1

(12)

(43) Date of publication: 10.03.2010 Bulletin 2010/10 (21) Application number: 08761717.1 (22) Date of filing: 02.06.2008

(51) International Patent Classification (IPC):  H01L 31/0232(2006.01) H01L 31/0216(2006.01) (86) International application number: PCT/FI2008/050321 (87) International publication number: WO 2008/145829 (04.12.2008 Gazette 2008/49)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR Designated Extension States: AL BA MK RS (30) Priority: 31.05.2007 FI 20070429 (71) Applicant: Teknillinen Korkeakoulu 02015 Tkk (FI)	(72) Inventor: IKONEN, Erkki FI-02210 Espoo (FI) (74) Representative: Brax, Matti Juhani  Berggren Oy Ab P.O. Box 16 00101 Helsinki 00101 Helsinki (FI)