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Current methods used for analyzing biomarkers involve expensive and time consuming techniques like the Sandwich ELISA which require lengthy incubation times, high reagent costs, and bulky optical equipment. We have developed a technique involving the use of a micro-channel with integrated electrodes, functionalized with receptors specific to target biomarkers. We have applied our biochip to the rapid electrical detection and quantification of target protein biomarkers using protein functionalized micro-channels. We successfully demonstrate detection of anti-hCG antibody, at a concentration of 1 ng ml−1 and a dynamic range of three orders of magnitude, in less than one hour. We envision the use of this technique in a handheld device for multiplex high throughput analysis using an array of micro-channels for probing various protein biomarkers in clinically relevant samples such as human serum for cancer detection.

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The linac coherent light source (LCLS), an x-ray free-electron laser project presently under construction at SLAC, uses a 2.856 GHz rf photocathode gun with a copper cathode for its electron source. While the copper cathode is performing well for the LCLS project, a cathode material with higher quantum efficiency would reduce the drive laser requirements and allow a greater range of operating conditions. Therefore a robust CsBr=Cu photocathode with greater than 50 times the quantum yield at 257 nm relative to the present LCLS copper cathode has been investigated. Preliminary experiments using a dedicated electron source development test stand at SLAC/SSRL are encouraging and are presented in this paper.

Currently, microbiological techniques such as culture enrichment and various plating techniques are used for detection of pathogens. These expensive and time consuming methods can take several days. Described below is the design, fabrication, and testing of a rapid and inexpensive sensor, involving the use of microelectrodes in a microchannel, which can be used to detect single bacterial cells electrically (label-free format) in real time. As a proof of principle, we have successfully demonstrated real-time detection of target yeast cells by measuring instantaneous changes in ionic impedance. We have also demonstrated the selectivity of our sensors in responding to target cells while remaining irresponsive to nontarget cells. Using this technique, it can be possible to multiplex an array of these sensors onto a chip and probe a complex mixture for various types of bacterial cells.

CsBr/Cr photocathodes were found [1,2] to meet the requirements of a multi-electron beam lithography system operating with a light energy of 4.8 eV (257nm). The fact that photoemission was observed with a light energy below the reported 7.3 eV band gap for CsBr was not understood. This paper presents experimental results on the presence of intra-band gap absorption sites (IBAS) in CsBr thin film photo electron emitters, and presents a model based on IBAS to explain the observed photoelectron emission behavior at energies below band gap. A fluorescence band centered at 330 nm with a FWHM of about 0.34 eV was observed in CsBr/Cr samples under 257 nm laser illumination which can be attributed to IBAS and agrees well with previously obtained synchrotron photoelectron spectra[1] from the valence band of CsBr films.

Photocathodes with relatively low energy spread ͑Ͻ0.5 eV͒ are required for electron sources in several applications including single and multiple electron beam inspection and lithography tools and free electron lasers. CsBr based photocathodes have been shown to be very robust and capable of operation at high current density ͑Ͼ150 A / cm 2 ͒ with very long lifetime ͑approximately hundreds of hours/spot͒. Experimental results of the photoelectron energy spread obtained in CsBr films deposited on both metal and InGaN substrates will be presented in this paper.

Low-temperature Aluminum-Germanium (Al-Ge) eutectic bonding has been investigated for monolithic threedimensional integrated circuits (3DIC) applications. Successful bonds using Al-Ge bilayer films as thin as 157 nm were achieved at temperatures as low as 435 °C, when applying 200 kPa downpressure for 30 minutes. The liquid phase of the eutectic composition ensured a seamless and void-free bond. The fracture energy of the Al-Ge bond (630 nm thick) was measured to be G c = 50.5 ± 12.7 J/m 2 , using double cantilever beam thin-film adhesion measurement technique. An array of silicon islands was attached onto an amorphous SiO 2 wafer using low-temperature Al-Ge bonding. These islands could be used to form devices on upper layers of monolithically integrated 3DICs.Index Terms-wafer bonding, monolithic integration, Al-Ge eutectic, 3DIC.