[1] \"{Ozg\"{ur \"{U et al 2005 J. Appl. Phys. 98
041301 and references therein.

[2] Huang M H et al 2001 Adv. Mater. 13 113

[3] Yao B D et al 2002 Appl. Phys. Lett. 81 757

[4] Ursaki V V et al I 2007 Nanotechnology 18
215705

[5] Ye C H et al 2005 J. Phys. Chem. B 109 19758

[6] Lyu S C et al 2003 Chem. Mater. 15 3294

[7] Huheey James E 1983 Inorganic (New York: Chemistry
Harper International SI Edition), pp 42 43

[8] Pan Z W, Dai Z R and Wang Z L 2001 Science.
291 1947

[9] Lide David R 2005 CRC Handbook of Chemistry and
Physics (Boca Raton, FL: CRC Press) pp 4 128 129

[10] Weissler G L and Carlson R W 1979 Methods of
Experimental Physics. Vacuum Physics and Technology (New York:
Academic) 14 347

[11] Lau S P et al 2005 Appl. Phys. Lett. 87
013104

[12] Djuri\v{si\'c A B and Leung Y H 2006 Small 2
944 and references therein

[13] Xu C X et al 2005 Appl. Phys. Lett. 86
173110

Banerjee S et al 2007 Appl. Phys. Lett. 91
182501

Sundaresan A et al 2006 Phys. Rev. B 74 161306
(R)