Orange Dye Based Field Effect Transistor As Humidity Sensor

In this study aqueous solution of organic semiconductor orange dye (8 wt.%) and sugar (8 wt.%), was prepared. The samples having structure of field effect transistor were fabricated by drop-casting of the solution on the surface-type interdigitated silver electrodes, deposited on ceramic alumina sheet. As a result, sol-gel elastic films of orange dye-sugar blend were fabricated. Drain-source volt-ampere characteristics were slightly non-linear and depend both on humidity level and applied gate-source terminal voltage. The fabricated transistors can be used as humidity sensors.