However, the mask patterns formed by these methods are mechanically produced at higher load and stress, damaging the mask surfaces and creating an oxidation layer that decreases the etching rate achieved with KOH solution. As a result, these damages remain on the processed surfaces [18–22]. In our previous study, we proposed a lower damage direct patterning of oxide layers by

mechanical processing. Sliding of an AFM diamond tip on a silicon surface forms protuberances under ambient conditions [23–25]. Proper mechanical action without plastic deformation by a sliding diamond tip on a silicon surface results in local mechanochemical oxidation with low damage [23–26]. The resulting oxide masks can be used for pattern transfer during selective wet etching processes [24–28]. Subsequently, by changing the diamond tip sliding scanning density, we realized the control of the etching rate GSK1210151A research buy of a silicon surface by KOH solution. We also evaluated the dependence of etching depth on KOH solution etching time [26]. An approach combining mechanical and electrical processes, such as an AFM technique that simultaneously uses a mechanical load and bias voltage, could be developed in the future. Reports on electrical and mechanical nanoprocessing have indicated that this complex approach can produce more electrically

resistant layers [29]. In this study, we attempted to fabricate a nanometer-scale PND-1186 clinical trial etching Ribonucleotide reductase mask pattern with low damage and evaluate the chemical resistance properties of the mechanically processed areas. First, we removed the natural oxide layer by diamond tip sliding at low load and then Tanespimycin mw increased the etching rate with KOH solution. Then, at higher load, we formed an etching resistance layer using mechanochemical oxidation. We fabricated protuberances with and without plastic deformation by mechanical processing. Finally, the surfaces were processed at low load and scanning density to remove

the natural oxide layer. The dependence of the KOH solution etching depth of these processed areas on etching time was also investigated. Methods The specimens were n-type Si (100) wafers. The samples were exposed in a clean atmosphere to allow their surfaces to become covered with a natural oxide layer less than 2 nm thick. First, mechanical processing was performed using diamond tip sliding with an AFM under atmospheric conditions at room temperature and humidity ranging between 50% and 80%. Dependence of KOH solution etching on load and scan density of mechanical pre-processing We clarified the conditions under which the etching rate increased after mechanical pre-processing due to the removal of the natural oxide layer. To evaluate the dependence of the KOH solution etching of the mechanically pre-processed area on the applied load and scanning density, diamond tips were directly slid on the Si (100) using the AFM, and square areas were processed as shown in Figure  1.