Tapping-mode has been the most widely used mode of operation in atomic force microscopy. Recent studies have shown that higher harmonics of the cantilever vibrations carries information about material properties such as stiffness, viscoelasticity or capillary forces. A major problem with higher harmonic imaging is the low signal to noise ratio. Here we present a micromachined cantilever that en...

Thermal cycling of a platinum modified, nickel aluminide (Ni,Pt)Al coated single crystal superalloy, between 1000 and 1150 C with 10 min holds at each temperature, and subject to a compressive uniaxial stress is reported. There are two major effects of the superimposed compressive stress not observed in the absence of the stress. One is that the rumpling pattern exhibits an asymmetry with an in...

Short cracks, extending to the interdiffusion zone, have been observed in platinum-modified nickel-aluminide diffusion coatings on single-crystal CMSX-4 superalloys after these have been subject to short (10 min) rapid thermal cycles. The cracks were revealed after removing the thermally grown oxide formed during cycling on the coating surfaces. Cracking was observed for coatings subject to the...

Enhanced grain growth in ultra-thin yttria-doped-zirconia (YDZ) films synthesized under ultraviolet (UV) irradiation is reported. The mean grain size in UV-activated 7.5 mol % yttria doped zirconia films nearly 56 nm thick increased to 85 nm upon annealing in an oxygen-rich ambient at 900 C for one hour, while in thermally grown YDZ they grew only to ~15 nm under identical annealing conditions....

We studied transport through ultrasmall Si quantum-dot transistors fabricated from siliconon-insulator wafers. At high temperatures, 4,T,100 K, the devices show single-electron or single-hole transport through the lithographically defined dot. At T,4 K, current through the devices is characterized by multidot transport. From the analysis of the transport in samples with double-dot characteristi...

Silicon carbide (4H) based metal–oxide–semiconductor field-effect transistors provide capabilities in high power and temperature inaccessible to silicon. However, the performance of thermally grown oxide-based devices remains limited by oxide/semiconductor interface defects. This research employs deposited dielectrics, Al2O3, rather than thermal oxidation. Investigation various pre-deposition p...