We report exceptional nanoscale wear and fouling resistance of ultrananocrystalline diamond (UNCD) tips integrated with doped silicon atomic force microscope (AFM) cantilevers. The resistively heated probe can reach temperatures above 600 degrees C. The batch fabrication process produces UNCD tips with radii as small as 15 nm, with average radius 50 nm across the entire wafer. Wear tests were performed on substrates of quartz, silicon carbide, silicon, or UNCD. Tips were scanned for more than 1 m at a scan speed of 25 mum s(-1) at temperatures ranging from 25 to 400 degrees C under loads up to 200 nN. Under these conditions, silicon tips are partially or completely destroyed, while the UNCD tips exhibit little or no wear, no signs of delamination, and exceptional fouling resistance. We demonstrate nanomanufacturing of more than 5000 polymer nanostructures with no deterioration in the tip.

We report thermoelectric voltage measurements between the platinum-coated tip of a heated atomic force microscope (AFM) cantilever and a gold-coated substrate. The cantilevers have an integrated heater-thermometer element made from doped single crystal silicon, and a platinum tip. The voltage can be measured at the tip, independent from the cantilever heating. We used the thermocouple junction between the platinum tip and the gold substrate to measure thermoelectric voltage during heating. Experiments used either sample-side or tip-side heating, over the temperature range 25-275 °C. The tip-substrate contact is ∼4 nm in diameter and its average measured Seebeck coefficient is 3.4 μV K(-1). The thermoelectric voltage is used to determine tip-substrate interface temperature when the substrate is either glass or quartz. When the non-dimensional cantilever heater temperature is 1, the tip-substrate interface temperature is 0.593 on glass and 0.125 on quartz. Thermal contact resistance between the tip and the substrate heavily influences the tip-substrate interface temperature. Measurements agree well with modeling when the tip-substrate interface contact resistance is 10(8) K W(-1).

The authors report field emission from nanometer-sharp tips of polarized PbZr x Ti 1Àx O 3 (PZT), silicon, and platinum. The PZT nanoemitters are fabricated in a batch fabrication process from single-crystal silicon tips that are coated with a 30 nm thick film of crystalline PZT. The nanoemitters start to emit electrons at fields as low as 2 V/lm and reach threshold emission, or turn-on, at fields as low as 3.9 V/lm. The turn-on field is 3.9 V/lm for PbZr 0.2 Ti 0.8 O 3 , 6.8 V/lm for PbZr 0.52 Ti 0.48 O 3 , and 10.75 V/lm for PbZr 0.8 Ti 0.2 O 3 . The silicon nanoemitters have an electron emission turn-on field of 7.2 V/lm, and the platinum nanoemitters have an electron emission turn-on field of 5.75 V/lm. Using a Fowler-Nordheim analysis, the calculated effective work function of the PbZr 0.2 Ti 0.8 O 3 film is 1.00 eV, and the field amplification factor is $

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