Papers by Keyword: Diamond Tip

Abstract: In this study, nanotwinned surface is fabricated on a Nickel alloy by means of a developed diamond panel with tips array. The diamond panel has an area of 10×10 mm2, and is grown using microwave chemical vapor deposition. The diamond tips are submicron in radius and formed on a silicon substrate with an array full of uniformed inverted pyramid pits. The nanotwinned surface is produced under the pressure of 1 MPa exerted by the diamond panel with tips array. Nanotwins are confirmed using transmission electron microscopy. The nanotwinned surface is generated by indention of diamond panel at room temperature using mechanical force, neither material removal nor chemical reagents. This is different from previous reports, in which high temperature, high pressure, chemical reagents or vacuum conditions are employed usually.

Abstract: A diamond tip with included angle of 90° and fillet radius of 45 nm is developed combining precision grinding and focused ion beam. Relatively high speed scratching at 8.4 m/s induced by the developed diamond tip is conducted on silicon (Si) (111) plane using an ultraprecision grinder. Width at the onset of chip formation on a Si wafer is 193 nm. Width and depth at the onset of crack formation are 1125 and 94 nm, respectively. Calculated normal forces at the onset of chip and crack formations are 424 μN and 14 mN, respectively, corresponding to the depth of cut is 44 and 466 nm.

Abstract: Effects of the scratching feed on machined surface and scratching forces are studied by using AFM-based nanomachining process scratching along the long axis of the cantilever. Results show: A deeper structure and rougher surface can be obtained at a smaller feed. An increase in the feed results in increases in scratching forces and the resultant force and a decrease in the normal force. Finally, all forces reach to a saturation value. The ratio of the cutting force to the thrust force in the plane perpendicular to the cutting edge can reveal effects of ploughing and cutting between the tip and the sample in the nanomachining process. Correspondingly, different states (cutting or ploughing) play a key role in formation of the machined surface at different feeds.

Abstract: Nano-scale fabrication of silicon substrate based on the use of atomic force microscopy (AFM) was demonstrated. A specially designed cantilever with diamond tip allows the formation of damaged layer on silicon substrate by a simple scratching process. A thin damaged layer forms in the substrate along scanning path of the tip. The damaged layer withstands against wet chemical etching in aqueous KOH solution. Diamond tip acts as a patterning tool like mask film for lithography process. Hence these sequential processes, called tribo-nanolithography, TNL, can fabricate 2D or 3D micro structures in nanometer range. This study demonstrates the fabrication processes of the micro cantilever and diamond tip as a tool for TNL. The developed TNL tools show outstanding machinability against single crystal silicon wafer. Hence, they are expected to have a possibility for industrial applications as a micro-to-nano machining tool.

Abstract: Nanometer-scale protuberance and groove processing was performed on a silicon (Si) surface by diamond tip sliding using atomic force microscopy (AFM). The protuberances of 0-5 nm height were obtained the silicon surface by using the diamond tip of approximately 200 nm radius and the grooves of 0-2 nm depth were processed by the tip of about 50 nm radius. It was observed that both protuberance and groove were produced using the tip of about 100 nm radius. Indentation measurements show the hardness of processed parts was greater than that of unprocessed parts. Potassium hydroxide (KOH) solution etching was performed on the mechanochemically processed sample. The processed areas were prevented from etching due to the formation of a dense oxide layer. This may be because the processed parts were oxidized by tip sliding due to the effect of mechanochemical oxidation.