While the literature is rich with data for the electrical behavior of nanotransistors based on semiconductor nanowires and carbon nanotubes, few data are available for ultrascaled metal interconnects that will be demanded by these devices. Atomic layer deposition (ALD), which uses a sequence of self-limiting surface reactions to achieve high-quality nanolayers, provides an unique opportunity to study the limits of electrical and thermal conduction in metal interconnects. This work measures and interprets the electrical and thermal conductivities of free-standing platinum films of thickness 7.3, 9.8, and 12.1 nm in the temperature range from 50 to 320 K. Conductivity data for the 7.3 nm bridge are reduced by 77.8% (electrical) and 66.3% (thermal) compared to bulk values due to electron scattering at material and grain boundaries. The measurement results indicate that the contribution of phonon conduction is significant in the total thermal conductivity of the ALD films.

This paper describes a new technique for strongly anchoring parylene (poly-para-xylylene) layers on a silicon^ substrate. Parylene has gained interest for MEMS applications due to its excellent properties. More specifically, because of its flexibility (Yong's modulus =4GPa), its chemical harrier properties, its conformal deposition and its biocompatibility, parylene is of great interest for microfluidics and BioMEMS. One of the issues with parylene processing is adhesion and delamination problems, occurring during fabrication or during device operation. Here, we report a new technique for anchoring parylene films on silicon using DRIEetched trenches and anchors. We demonstrate a new way to completely protect the adhesion of parylene even when exposed to aggressive chemicals.

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The field of nanofluidics dealing with nL fluids is growing, and sensors for monitoring ever smaller flow rates (-nL/min) are needed. This paper presents a new, sensitive micromachined thermal sensor for measuring flow rates. The integrated sensor uses a high-TCR (temperature coefficient of yesistance) carbon sensing element obtained from ion-implanted parylene. The ion-implanted carbon element has a high temperature coefficient of resistance of -2%PC and is embedded in a freestanding microchannel suspended from the substrate. The developed sensor has been characterized for flow measurements with a volumetric flow sensitivity of 380 pV/(nlimin) under a constant current bias with a power consumption of only 28 pW. To our knowledge, this is the first such nanofluidic carbon flow sensor and its sensitivity is better than any of flow sensors reported to date.

This paper describes the first work of using wafer-sized flexible parylene-valved actuator skins (total thickness ~ 20 µm) for micro adaptive flow control. The check-valved actuator skins feature vent-through holes with tethered valve caps on the membrane to regulate pressure distribution across the skins. The skins were integrated onto MEMS wings and were tested in the low-speed wind tunnel for aerodynamic evaluation. The test results have shown very significant effects on the aerodynamic performances. Compare to the reference MEMS wings (no actuators), both the lift and thrust of the parylene check-valved wings were improved by more than 50%. This is the first experimental result to demonstrate that the application of MEMS actuator skins for flow control is very promising.