Water wettability of Si(111) and (001) surfaces prepared to be reconstructed, atomic-hydrogen terminated and thinly oxidized in an ultrahigh vacuum chamber

作者：Miyagi Tomoaki; Sasahara Akira; Tomitori Masahiko^*

来源：Applied Surface Science, 2015, 349: 904-910.

DOI：10.1016/j.apsusc.2015.04.176

• Silicon
• Water contact angle
• Super-hydrophilicity
• Optical interference fringe method
• Atomic hydrogen termination
• Oxidation

Water contact angles on three types of Si(1 1 1) and (0 0 1) surfaces were measured in nitrogen gas atmosphere without exposing them to air; the surfaces were prepared to be (I) cleaned and reconstructed, subsequently (II) atomic hydrogen (H) terminated, or (III) thinly oxidized in an ultrahigh vacuum (UHV) chamber. The surfaces were characterized by Auger electron spectroscopy and atomic force microscopy. The H-terminated Si surfaces showed as less hydrophilic with a water contact angle of about 37 degrees on the (1 1 1) and about 60 degrees on the (0 0 1) surface, respectively. The clean and oxidized surfaces showed as super-hydrophilic with the angles less than 6 degrees. To quantitatively evaluate the contact angles on the super-hydrophilic surfaces, an optical interference fringe method was used under an optical microscope in air. The most super-hydrophilic surface was the oxidized Si(1 1 1) surface. The reactivity of the Si surfaces and their degree of hydroxyl group termination to the Si surfaces responsible for water wettability were discussed.

• 出版日期2015-9-15