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Piezoelectric micromachined ultrasound transducer (PMUT) matrix arrays were fabricated containing novel through-silicon interconnects and integrated into intracardiac catheters for in vivo real-time 3-D imaging. PMUT arrays with rectangular apertures containing 256 and 512 active elements were fabricated and operated at 5 MHz. The arrays were bulk micromachined in silicon-on-insulator substrates, and contained flexural unimorph membranes comprising the device silicon, lead zirconate titanate (PZT), and electrode layers. Through-silicon interconnects were fabricated by depositing a thin-film conformal copper layer in the bulk micromachined via under each PMUT membrane and photolithographically patterning this copper layer on the back of the substrate to facilitate contact with the individually addressable matrix array elements. Cable assemblies containing insulated 45-AWG copper wires and a termination silicon substrate were thermocompression bonded to the PMUT substrate for signal wire interconnection to the PMUT array. Side-viewing 14-Fr catheters were fabricated and introduced through the femoral vein in an adult porcine model. Real-time 3-D images were acquired from the right atrium using a prototype ultrasound scanner. Full 60? ? 60? volume sectors were obtained with penetration depth of 8 to 10 cm at frame rates of 26 to 31 volumes per second. [ABSTRACT FROM AUTHOR]

Abstract: The electromechanical performance of piezoelectric scanning mirrors for endoscopy imaging is presented. The devices are supported by a single actuating cantilever to achieve a high fill factor, the ratio of mirror area to the combined mirror and actuator area. The largest fill factor devices (74%) achieved 10° mechanical scan range at ±10V with a 300μm long cantilever. The largest angular displacement of 30° mechanical scan range was obtained with a 500μm long cantilever device with a 63% fill factor driven at 40Vpp. A systematic investigation of device performance (displacement and speed) as a function of fabrication and operational parameters including the stress balance in the cantilever revealed unexpectedly large displacements with lack of inversion at the coercive field. An interpretation of the results is presented based on piezoelectric film domain orientation and clamping with supporting piezoelectric film characterization measurements. [Copyright &y& Elsevier]

Abstract: The design, fabrication and characterization of a compact optical biosensor based on an input grating coupler are presented. The sensor device consists of a waveguide-integrated single grating structure. The optical reader is based on the use of a largely tunable, small footprint infrared laser for wavelength interrogation of the sensor and on edge-detection of waveguided modes, resulting in a compact configuration. A multiplexing approach is illustrated and a two-output sensor system is demonstrated. The device is packaged in a microfluidic cartridge for sample handling. The volumetric sensing performance of the system is characterized and a limit of detection of 1×10−5 RIU is reported while the surface sensing capability is demonstrated by detection of protein diluted down to 200ng/ml. [Copyright &y& Elsevier]

Abstract: Dense one-dimensional arrays of high aspect ratio Faraday cups have been microfabricated for application as position sensitive charged particle detectors. The method developed to fabricate these Faraday cup arrays utilizes deep reactive ion etching (DRIE) of low resistivity silicon, conformal deposition of an insulator and metal, and a novel method for patterning the cup-to-fanout interconnect to allow for high cup density. Linear arrays of 64 cups have been fabricated with cups ranging in width from 15 to 45μm. Cup depth-to-width aspect ratios in excess 8:1 can be realized with the method. The minimum spacing between cups demonstrated here was 5μm. Linear fill factors of the Faraday cups ranged from 50% to 90%, depending on the cup geometry and pitch. The capacitance and leakage current measurements on microfabricated Faraday cups will be discussed along with an electrical model and predictions of the detector performance. [Copyright &y& Elsevier]