A GAS-SENSITIVE FIELD-EFFECT TRANSISTOR UTILIZING A THIN-FILM OF LEAD PHTHALOCYANINE AS THE GATE MATERIAL

The feasibility of making gas sensors by incorporating MPc films in transistors has also been demonstrated using metal/oxide/semiconductor (MOS) diodes coated with LB films of an asymmetrically substituted copper phthalocyanine. The capacitance-voltage curves for these devices were sensitive to part per million concentrations of NO//2. Recently, authors have attempted the fabrication of a more sensitive NO//2-responsive transistor by thermally evaporating a thin film of lead phthalocyanine (PbPc) over the gate oxide region of a field effect transistor (FET). In this letter they report fabrication details and preliminary results on the performance characteristics of the device in NO//2 at concentrations of parts per billion (ppb, i. e. 1 in 10**9).