A NOVEL pH SENSITIVITY OF SnO2THIN FILM BASED EGFET PREPARED USING CHEMICAL BATH METHOD

Nanocrystalline (NC) tin dioxide (SnO 2 ) thin film has been prepared using chemical bath method at low working temperature onto SiO 2 /Si substrates. The structural and morphological properties were studied through X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The as-deposited thin film appeared with tetragonal rutile structure. The crystallization of SnO 2 film was achieved when the film was exposed to anneal at [Formula: see text]C. NC SnO 2 thin film was successfully utilized as an extended gate field-effect transistor (EGFET) pH sensing. NC SnO 2 film based pH-EGFET sensor displayed a notable pH sensing performance, where the sensitivity and the linearity values are equal to 25.7 (mV/pH) and 0.8489 within 2–12 range consecutive. The NC SnO 2 thin film sensor has shown good pH sensor stability and reliability; thus it can be considered the best choice for flexible and disposable biosensors.