This method is unique and promising because it requires no chemical solution that degrades

Ge p38 MAPK inhibitor surfaces but is used in conventional wet-chemical treatments in Si processes. Conclusions We studied the metal-induced chemical etching of Ge(100) surfaces in water. We showed that noble metal particles such as Ag and Pt induce anisotropic etching. The mechanism of this formation is TH-302 the catalytic activity of noble metals to reduce O2 molecules in water, which promotes preferential oxidation around metallic particles. Etch pits are formed to roughen the surface due to the soluble nature of GeO2. A key parameter for controlling the reaction is the dissolved oxygen concentration of water. We proposed that enhanced etching can be used positively toward the nanoscale patterning of Ge surfaces in water. This idea was confirmed by a set of AFM experiments in which a cantilever probe on Ge(100) was scanned in either water or air. We investigated the dependences of probe material, pressing force, and dissolved oxygen concentration on etched depth. We demonstrated the metal-assisted patterning of Ge surfaces in water, the mechanism of which is similar to that of the metal-induced pit formation mentioned above. Acknowledgments The authors would like to selleckchem thank Dr. Yusuke Yamada for the preparation of the Pt particles. The work was supported in part by a Grant-in-Aid for

Young Scientists (A) (grant no.: 24686020) from Japan Society for the Promotion of Science. It was also supported in part by grants from Amano Institute

of Technology and 17-DMAG (Alvespimycin) HCl Ichijyu Industrial Science and Technology Promotion Foundation. References 1. Matsubara H, Sasada T, Takenaka M, Takagi S: Evidence of low interface trap density in GeO 2 /Ge metal-oxide-semiconductor structures fabricated by thermal oxidation. Appl Phys Lett 2008, 93:032104.CrossRef 2. Leancu R, Moldovan N, Csepregi L, Lang W: Anisotropic etching of germanium. Sens Actuators A-Phys 1995, 46:35–37.CrossRef 3. Fang C, Foll H, Carstensen J: Electrochemical pore etching in germanium. J Electroanal Chem 2006, 589:259–288.CrossRef 4. Kern W, Puotinen DA: Cleaning solutions based on hydrogen peroxide for use in silicon semiconductor technology. RCA Review 1970, 31:187–206. 5. Ohmi T: Total room temperature wet cleaning for Si substrate surface. J Electrochem Soc 1996, 143:2957–2964.CrossRef 6. Onsia B, Conard T, De Gendt S, Heyns M, Hoflijk I, Mertens P, Meuris M, Raskin G, Sioncke S, Teerlinck I, Theuwis A, Van Steenbergen J, Vinckier C: A study of the influence of typical wet chemical treatments on the germanium wafer surface. In Ultra Clean Processing of Silicon Surfaces VII. Volume 103–104. Edited by: Mertens P, Meuris M, Heyns M. Switzerland: Solid State Phenomena; 2005:27–30. 7. Blumenstein C, Meyer S, Ruff A, Schmid B, Schafer J, Claessen R: High purity chemical etching and thermal passivation process for Ge(001) as nanostructure template. J Chem Phys 2011, 135:064201.CrossRef 8.