The current state of novel technology, surface microfabricated ultrasonic transducers, is reported. Experiments demonstrating both air and water transmission are presented. Air-coupled longitudinal wave transmission through aluminum is demonstrated, implying a 110 dB dynamic range for transducers at 2.3 MHz in air. Water transmission experiments from 1 to 20 MHz are performed, with a measured 60 dB SNR at 3 MHz. A theoretical model is proposed that agrees well with observed transducer behavior. Most significantly, the model is used to demonstrate that microfabricated ultrasonic transducers constitute an attractive alternative to piezoelectric transducers in many applications.

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Bias controlled capacitive driven cantilever oscillation for high resolution dynamic force microscopy Appl. Phys. Lett. 102, 073110 (2013) Friction measurement on free standing plates using atomic force microscopy Rev. Sci. Instrum. 84, 013702 (2013) A correlation force spectrometer for single molecule measurements under tensile load J. Appl. Phys. 113, 013503 (2013) Compact metal probes: A solution for atomic force microscopy based tip-enhanced Raman spectroscopy Rev. Sci. Instrum. 83, 123708 (2012) Note: Radiofrequency scanning probe microscopy using vertically oriented cantilevers Rev. Sci. Instrum. 83, 126103 (2012) Additional information on Appl. Phys. Lett.

Cataloged from PDF version of article.Higher harmonics in tapping-mode atomic force microscopy offers the potential for imaging and sensing\ud material properties at the nanoscale. The signal level at a given harmonic of the fundamental mode can be\ud enhanced if the cantilever is designed in such a way that the frequency of one of the higher harmonics of the\ud fundamental mode ~designated as the resonant harmonic! matches the resonant frequency of a higher-order\ud flexural mode. Here we present an analytical approach that relates the amplitude and phase of the cantilever\ud vibration at the frequency of the resonant harmonic to the elastic modulus of the sample. The resonant\ud harmonic response is optimized for different samples with a proper design of the cantilever. It is found that\ud resonant harmonics are sensitive to the stiffness of the material under investigation

Cataloged from PDF version of article.An expandable system has been developed to operate multiple probes for the atomic force microscope in parallel at high speeds. The combined improvements from parallelism and enhanced tip speed in this system represent an increase in throughput by over two orders of magnitude. A modular cantilever design has been replicated to produce an array of 50 cantilevers with a 200 μm pitch. This design contains a dedicated integrated sensor and integrated actuator where the cells can be repeated indefinitely. Electrical shielding within the array virtually eliminates coupling between the actuators and sensors. The reduced coupling simplifies the control electronics, facilitating the design of a computer system to automate the parallel high-speed arrays. This automated system has been applied to four cantilevers within the array of 50 cantilevers, with a 20 kHz bandwidth and a noise level of less than 50 Å. For typical samples, this bandwidth allows us to scan the probes at 4 mm/s.\ud © 1998 American Institute of Physic