Nano Archive

A study of LAO nanopatterns on Si substrates of different crystallographic orientations

Kulkarni, G. U. (2007) A study of LAO nanopatterns on Si substrates of different crystallographic orientations. Solid State Communications, 14 . pp. 89-93. ISSN 10.1016/j.ssc.2007.01.027

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Official URL: http://dx.doi.org/10.1016/j.ssc.2007.01.027

Abstract

Oxide nanopatterns have been drawn on Si (100), (110) and (111) substrates using the AFM based method of local anodic oxidation (LAO) employing negative tip voltages of 5, 8 and 10 V. The same tip was used in all the cases and experimental parameters such as tip velocity and humidity were kept fixed. The total volume occupied by the oxide estimated based on the z-profiles of the raised patterns as well as of the trenches obtained after removing the oxide by treating with dilute HF, is similar to that of vitreous SiO2 at a moderate tip voltage of 8 V. A smaller voltage of 5 V produced a defect oxide (SiOx) as seen on the (111) surface while, a tip voltage of 10 V gave rise to a porous oxide that occupied, in relation to vitreous SiO2, ~ 14% more volume in the case of (100) and (111) surfaces and ~ 35% with the (110) surface. The nature of the oxide is related to the surface densities of the substrates, the (110) surface being dense requires more voltage to initiate oxidation but produces voluminous oxide. Nanoindentation on the LAO pattern yielded a hardness value of 4.3 GPa.

Item Type:Article
Subjects:Physical Science > Nano objects
Material Science > Nanochemistry
Divisions:Faculty of Engineering, Science and Mathematics > School of Physics
ID Code:1605
Deposited By:JNCASR
Deposited On:03 Apr 2009 06:37
Last Modified:12 Aug 2009 11:40

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