A technique based on suspended islands is described to measure the in-plane thermal conductivity of thin films and nano-structured materials, and is also employed for measurements of several samples with a single measurement platform. Using systematic steps for measurements, the characterization of the thermal resistances of a sample and its contacts are studied. The calibration of the contacts in this method is independent of the geometry, size, materials, and uniformity of contacts. To verify the technique, two different Si samples with different thicknesses and two samples of the same SiN(x) wafer are characterized on a single device. One of the Si samples is also characterized by another technique, which verifies the current results. Characterization of the two SiN(x) samples taken from the same wafer showed less than 1% difference in the measured thermal conductivities, indicating the precision of the method. Additionally, one of the SiN(x) samples is characterized and then demounted, remounted, and characterized for a second time. The comparison showed the change in the thermal resistance of the contact in multiple measurements could be as small as 0.2 K/μW, if a similar sample is used.

The design, fabrication and characterization of a recently developed test platform for the characterization of nanoscale properties of thin films are presented. Platforms are comprised of a microfabricated cascaded thermal actuator system and test specimen. The cascaded thermal actuator system is capable of providing tens of microns of displacement and tens of milli-Newton forces simultaneously while applying a relatively low temperature gradient across the test specimen. The dimensions of the platform make its use possible in both the scanning/transmission electron microscope environments and on a probe station under an optical microscope. Digital image correlation was used to obtain similar accuracy (∼10 nm) for displacement measurements in both a SEM and under an optical microscope. Proof of concept experiments were performed on freestanding 250 nm thick Pt thin films.

Recently, organic/inorganic hybrid nanocomposites being the future in electronic applications. In this paper, we have investigated hybrid nanocomposite zinc phthalocyanine (ZnPc)/zinc oxide nanoparticles (ZnO). ZnPc/ZnO hybrid nanocomposites were prepared with different ratios (wt/wt) (1/0), (0/1), (0.75/0.25), (0.5/0.5), (0.25/0.75), and, deposited on glass substrates by spin coating technique. X-Ray diffraction investigate the structural of ZnPc/ZnO thin films and studied the morphological properties using field emission scan electron microscopy, the surface of ZnPc/ZnO hybrid nanocomposites shows the presence of nanorod-like structures represented the organic material (ZnPc) and spherical nanoparticles for (ZnO), that is depending on the ratio of the blend. In ratio (0.5/0.5) we get the preferred homogeneous surface between like-nanorod and spherical shapes were show various properties from pure compounds which used to prepare the blend. The distribution of ZnO nanoparticles on ZnPc particles nanorods led to the disappearance feature of ZnO morphological characterize and ZnPc decorated was dominated on the hybrid nanocomposite structure.

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Pt deposited by focused ion beam (FIB) is a common material used for attachment of nanosamples, repair of integrated circuits, and synthesis of nanostructures. Despite its common use little information is available on its thermal properties. In this work, Pt deposited by FIB is characterized thermally, structurally, and chemically. Its thermal conductivity is found to be substantially lower than the bulk value of Pt, 7.2 W m(-1) K(-1) versus 71.6 W m(-1) K(-1) at room temperature. The low thermal conductivity is attributed to the nanostructure of the material and its chemical composition. Pt deposited by FIB is shown, via aberration corrected TEM, to be a segregated mix of nanocrystalline Pt and amorphous C with Ga and O impurities. Ga impurities mainly reside in the Pt while O is homogeneously distributed throughout. The Ga impurity, small grain size of the Pt, and the amorphous carbon between grains are the cause for the low thermal conductivity of this material. Since Pt deposited by FIB is a common material for affixing samples, this information can be used to assess systematic errors in thermal characterization of different nanosamples. This application is also demonstrated by thermal characterization of two carbon nanofibers and a correction using the reported thermal properties of the Pt deposited by FIB.

In order to measure in-plane thermal conductivity, electrical resistivity, and Seebeck Coefficient of Phononic Crystals (PnCs) a micro device is designed and fabricated to host different nano-scale samples. The device is comprised of two SiNx suspended membranes with patterned by Pt on top and covered by AlN. The Pt deposited on these two membranes or islands are dual-purpose temperature sensors and heaters. One side of a sample can be attached to each of the two islands. In this way 1-D heat flow can be established in the material to be tested. Covering the islands with AlN enhances the uniformity of temperature on each sensor. Moreover, AlN is an excellent electrical insulator, and it protects the platinum sensors from different sources of doping such as gallium ions used for patterning, depositing, mounting, or demounting different samples on the islands. This ensures the thermo-electric properties of the sensors on the platform do not change after each measurement. Using this design, it is demonstrated that one platform can be used for measurement of a silicon slab and then a separate measurement of a 1-D PnC fabricated from the same sample. The 1-D PnC had a Si-W structure that was fabricated using a Focused Ion Beam (FIB) and a Gas Injection System (GIS) capable of depositing W.

A technique is presented for determination of the depletion of the etchant, etched depth, and instantaneous etch rate for Si etching with XeF2 in a pulsed etching system in real time. The only experimental data required is the pressure data collected temporally. Coupling the pressure data with the knowledge of the chemical reactions allows for the determination of the etching parameters of interest. Using this technique, it is revealed that pulsed etching processes are nonlinear, with the initial etch rate being the highest and monotonically decreasing as the etchant is depleted. With the pulsed etching system introduced in this paper, the highest instantaneous etch rate of silicon was recorded to be 19.5 µm min−1 for an initial pressure of 1.2 Torr for XeF2. Additionally, the same data is used to determine the rate constant for the reaction of XeF2 with Si; the reaction is determined to be second order in nature. The effect of varying the exposed surface area of Si as well as the effect that pressure has on the instantaneous etch rate as a function of time is shown applying the same technique. As a proof of concept, an AlN resonator is released using XeF2 pulses to remove a sacrificial poly-Si layer.

The mechanical behavior of polycrystalline Pt thin films is reported for thicknesses of 75 nm, 100 nm, 250 nm, and 400 nm. These thicknesses correspond to transitions between nanocrystalline grain morphology types as found in TEM studies. Thinner samples display a brittle behavior, but as thickness increases the grain morphology evolves, leading to a ductile behavior. During evolution of the morphology, dramatic differences in elastic moduli (105–160 GPa) and strengths (560–1700 MPa) are recorded and explained by the variable morphology. This work suggests that in addition to the in-plane grain size of thin films, the transitions in cross-sectional morphologies of the Pt films significantly affect their mechanical behavior.