This paper describes a semi-automated conductive ink process used for packaging MEMS devices. The method is applied to packaging of MEMS sensors for wind tunnel testing. The primary advantage of the method is a reduction in surface topology between the package and the integrated MEMS sensors. In this paper we explore the relationship between trace dimensions, resistivity, and deposition parameters such as feed rate, tip-substrate separation and tip diameter. Using this procedure it is possible to generate interconnects between a PC board and MEMS sensor chip with a topology of less than 25 micrometers.

Here, we present microfluidic methods to fabricate complex hydrogel structures for 3D tissue or organ-like cell structures in vitro. First, a microfluidic system to continuously synthesize chemically and physically anisotropic Ca–alginate hydrogel microfibers is proposed to enable the guidance of cell proliferation and differentiation. Next, the microfluidic preparation methods for yarn-ball-shape hydrogel particles and extremely-small hydrogel microspheres. Finally, a newly developed micro-molding and bonding method for hydrogel micro-patterned plates is reported.

We are developing a new non-contact and non-destructive imaging technique which requires no sample preparation and provides similar content information as FTIR or Raman spectroscopy while being immune to fluorescence and offers a potentially faster scan rate and/or higher spatial resolution. It utilizes photo-thermal heating of the sample with a quantum cascade laser (or other suitable infrared laser) and measuring the resulting increase in thermal emissions by either an infrared (IR) detector or a laser probe consisting of a visible laser reflected from the sample. The latter case allows for further increases in the spatial resolution from ∼10 μm to ∼1 μm or better, with suitable experimental conditions. Since the thermal emission signal is proportional to the absorption coefficient, by tuning the wavelength of the IR laser we can directly measure the IR spectrum of the sample. By raster scanning over the surface of the sample we can obtain maps of the chemical composition of the sample surface. We demonstrate this technique by imaging the surface of a micro-fabricated flow-through chemical vapor preconcentrator consisting of a silicon frame and a suspended-perforated polyimide membrane with a pair of platinum heater traces, coated with a custom sorbent polymer for selective sorption of analyte. We measure the spatial resolution of our photo-thermal imaging system as well as discuss the conditions under which the spatial resolution can be further increased from the far-field diffraction limited resolution given by the combination of the imaging optic and IR excitation laser wavelength.