Jeb H. Flemming

Fabrication and Testing of a Microneedles Sensor Array for p-Cresol Detection with Potential Biofuel Applications

We present a miniaturized high-throughput sensor array that will augment biofuel technology by facilitating in situ biochemical measurements upon micrometer-scale surfaces of leaves, stems, or petals. We used semiconductor processing to photopattern Foturan glass wafers and fabricated gold-plated microscopic electrode needles (ElectroNeedles) that pierced 125-mum-thick surfaces without deformation. The 5 x 5 or 10 x 10 arrays of ElectroNeedles can analyze 25 or 100 samples simultaneously, increasing throughput. Each microneedle in the array can also be individually addressed and selectively functionalized using diazonium electrodeposition, conferring multiplexing capability. Our microfabrication is a simple, inexpensive, and rapid alternative to the time-, cost-, and protocol-intense, deep-reactive-ion-etching Bosch process. We validated the system performance by electrochemically detecting p-cresol, a phenolic substrate for laccase, an enzyme that is implicated in lignin degradation and therefore important to biofuels. Our limits of detection (LOD) and quantization (LOQ) for p-cresol were 1.8 and 16microM, respectively, rivaling fluorescence detection (LOD and LOQ = 0.4 and 3microM, respectively). ElectroNeedles are multiplexed, high-throughput, chip-based sensor arrays designed for minimally invasive penetration of plant surfaces, enabling in situ and point-of-test analyses of biofuel-related biochemicals.

Evaluation of Mini/Micro-Pumps for Micro-Chem-Lab™

The performance of a selective group of mini and micro-pumps has been evaluated for use in gas phase detection for the Micro-Chem-Lab™. Our major assessment criteria are: flow rate, pressure drop across the pump, and electrical current drawn by the pump. Two pumping configurations have been investigated: (1) upstream pumping to build up pressure head and (2) downstream pumping to draw vacuum. Four mini-pumps (T-Square, SP 250 EC, SP 135 FZ-4, and KNF Neuberger) have been studied. Each of these pumps has been tested to determine whether they meet our requirements of high head pressure, high flow rate, and low power consumption. We have also assessed different mechanisms for pumping gas in micro-domains — specifically, a valveless diffuser/nozzle micro-pump, a LIGA diaphragm micro-pump and a micro drag pump. However our preliminary findings reveal that these micro-pumps do not meet our minimal requirements for use in the μChemLab™.Copyright

Bio micro fuel cell grand challenge final report.

Christopher Apblett, Kent Schubert, Bruce Kelley, Andrew Walker, Blake Simmons, Ted Borek, Stephen Meserole, Todd Alam, Brian Cherry, Greg Roberts, Jim Novak, Jim Hudgens, Dave Peterson, Jason Podgorski, Susan Brozik, Jeb Flemming, Stan Kravitz, David Ingersoll, Steve Eisenbies, Randy Shul, Sarah Rich, Carrie Schmidt, Mike Beggans, Jeanne Sergeant, Chris Cornelius, Cy Fujimoto, Micheal Hickner, Swapnil Chabra, Suzanne Ma, Joanne Volponi, Micheal Kelly, Kevin Zavadil, Chad Staiger, Patricia Dolan, Monica Manginell, Jason Harper, Dan Doughty, Steve Casalnuovo

Cost-Effective Precision 3D Glass Microfabrication for Advanced Packaging Applications

Todays packaging has become the limiting element in system cost and performance for IC development. Assembly and packaging technologies have become primary differentiators for manufactures of consumer electronics and the main enabler of small IC product development. Traditional packaging approaches to address the needs in these “High Density Portable” devices, including FR4, liquid crystal polymers, and Low Temperature Co-Fire Ceramics, are running into fundamental limits in packaging layer thinness, high density interconnects (HDI) size and density, and do not present solutions to in-package thermal management, and optical waveguiding. In this talk, 3D Glass Solutions will present on our efforts to create advanced microelectronic packing solutions using our APEX™ Glass ceramic which offers a single material capable of being simultaneously used for ultra-HDI through glass vias (TGVs), optical waveguiding, and in-package microfluidic cooling. In this talk we will discuss our latest results in wafer-level ...

Cost effective Precision 3D Glass Microfabrication for Electronic Packaging

The most singular focus of the electronics industry during the last 50 years has been to miniaturize ICs by miniaturization of transistors and on-chip interconnections. Two major problems are fores...

Cost Effective Production of Glass Interposers for 3D ICs Using APEX(TM) Glass Ceramic

The most singular focus of the electronics industry during the last 50 years has been to miniaturize ICs by miniaturization of transistors and on-chip interconnections. Two major problems are foreseen with this approach; electrical leakage and lack of improved electrical performance beyond 16nm. As a result, industry is transitioning from the current SOC-based approach to a through-silicon-via (TSV) based 3D IC-stacked approach. However, a major challenge remains; these 3D ICs need to be interconnected to other ICs with a much higher number of I/Os than are available with current ceramic or organic interposers. While silicon interposers currently in development can provide these high I/Os, they cannot do so at low enough cost. In this talk, we will present on our efforts in glass interposers fabrication. Glass interposers possess many advantages over silicon interposers including: cost, production time, and scale. Life MicroFabs APEX™ Glass ceramic is a photo-sensitive material used to create high densit...

Detection of carbon monoxide (CO) as a furnace byproduct using a rotating mask spectrometer.

Sandia National Laboratories, in partnership with the Consumer Product Safety Commission (CPSC), has developed an optical-based sensor for the detection of CO in appliances such as residential furnaces. The device is correlation radiometer based on detection of the difference signal between the transmission spectrum of the sample multiplied by two alternating synthetic spectra (called Eigen spectra). These Eigen spectra are derived from a priori knowledge of the interferents present in the exhaust stream. They may be determined empirically for simple spectra, or using a singular value decomposition algorithm for more complex spectra. Data is presented on the details of the design of the instrument and Eigen spectra along with results from detection of CO in background N2, and CO in N2 with large quantities of interferent CO2. Results indicate that using the Eigen spectra technique, CO can be measured at levels well below acceptable limits in the presence of strongly interfering species. In addition, a conceptual design is presented for reducing the complexity and cost of the instrument to a level compatible with consumer products.

Biocompatible self-assembly of nano-materials for Bio-MEMS and insect reconnaissance.

This report summarizes the development of new biocompatible self-assembly procedures enabling the immobilization of genetically engineered cells in a compact, self-sustaining, remotely addressable sensor platform. We used evaporation induced self-assembly (EISA) to immobilize cells within periodic silica nanostructures, characterized by unimodal pore sizes and pore connectivity, that can be patterned using ink-jet printing or photo patterning. We constructed cell lines for the expression of fluorescent proteins and induced reporter protein expression in immobilized cells. We investigated the role of the abiotic/biotic interface during cell-mediated self-assembly of synthetic materials.