Wp. Kang et al., A NEW HYDROGEN SENSOR USING A POLYCRYSTALLINE DIAMOND-BASED SCHOTTKY DIODE, Journal of the Electrochemical Society, 141(8), 1994, pp. 2231-2234
A new hydrogen sensor utilizing plasma-enhanced chemical vapor deposit
ed diamond in conjunction with palladium (Pd) metal has been developed
. The device is fabricated in a layered Pd/undoped diamond/p-doped dia
mond Schottky diode configuration. Hydrogen sensing characteristics of
the device have been examined in terms of sensitivity, linearity, res
ponse rate, and response time as a function of temperature and hydroge
n partial pressure. Hydrogen adsorption activation energy is investiga
ted in the temperature range from 27 to 85-degrees-C. Analysis of the
steady-state reaction kinetics using the I-V method confirm that the h
ydrogen adsorption process is responsible for the barrier height chang
e in the diamond Schottky diode. The ability to fabricate diamond-base
d hydrogen sensor on a variety of substrates makes the device very ver
satile for gas sensing.