Mb. Stern et al., NANOCHANNEL FABRICATION FOR CHEMICAL SENSORS, Journal of vacuum science & technology. B, Microelectronics and nanometer structures processing, measurement and phenomena, 15(6), 1997, pp. 2887-2891
In a novel chemical sensor, the chemical charge coupled device (CCD),
electrostatic fields in nanocapillary channels smaller than a Debye le
ngth will be used to separate and concentrate ions in solution with a
predicted detection limit of < 1 x 10(-13) M. Conventional integrated
circuit techniques are used to deposit thin dielectric and amorphous-S
i films on a Si substrate and to lithographically define channel and r
eservoir structures. Hollow Si3N4 nanochannels with heights between 20
and 100 nm, widths between 0.5 and 20 mu m, and lengths up to 5 mm ha
ve been fabricated by wet chemical etching of a sacrificial amorphous-
Si layer in tetramethylammonium hydroxide. Initial modeling of a three
-phase chemical CCD predicts the ability to select and concentrate ion
ic constituents by many orders of magnitude, according to their diffus
ion coefficients. (C) 1997 American Vacuum Society.