In order to detect interested matters in fields, various lab-on-a-chips where chemical, physical, or biological sensors are
loaded have been developed. eNOSE can be a representative example among them. Because animals can sense
300~1000 different chemicals by olfactory system – smell –, the olfactory system has been spotlighted as new materials
in the field of sensing. Those investigations, however, are usually focused on how to detect signals from the olfactory
neurons or receptors loaded on chips and enhance sensing efficacy of chips. Therefore, almost of those chips are
designed for only one material sensing. Multi-sensing using multi-channels will be needed when the olfactory systems
are adopted well on chips. For multiple sensing, we developed an addressable cell array. The chip has 38 cell-chambers
arranged in a circle shape and different cell types of thirty eight can be allocated with specific addresses on the chip
without any complex valve system. In order to confirm the cell addressing, we loaded EGFP-transfected and empty
vector-transfected HEK293a cells into inlets of the cell array in a planned address and those cells were positioned into
each chamber by brief aspiration. The arrayed cells were confirmed as a specific pattern through EGFP and nuclei
staining. This cell array which can generate address of sensor materials like cells with their own specification is expected
to be applied to a platform for a biosensor chip at various sensing fields.
A study of the laser annealing effect for the thermal evaporated Al thin film onto micromirrors of optical switch and (100) Si subtrates is reported. The 2 X 2 optical switches has been fabricated through DRIE process. The input laser energy has been changed from 150 mJ/pulse to 350 mJ/pulse and the number of pulse also changed. The surface morphology is investigated by SEM micrograph and the roughness is examined by AFM. The reflectivities of the samples are measured by IR reflectometer and the results are normalized with gold. In case of the energy above 200 mJ/pulse, the reflectivities are improved up to above 0.98 from the incident beam region of 1300 nm to 1550 nm. The improvement of reflectivity is caused by the reflow process induced laser annealing. By the reflow process the grain have been growth and agglomerated for the surface planarization. The energy for planarization is sufficient as 1 pulse incident laser beam. According to the number of pulses, reflectivity is somewhat degraded by excess heat of reflow in case of above 5 pulses. There is minor morphology change with input laser energy.