Orange Dye Based Temperature Sensor

In this study, organic semiconductor orange dye (8 wt.%) and sugar (8 wt.%) aqueous solution was prepared. The temperature sensors were fabricated by drop-casting of the solution on the surface-type, interdigitated silver electrodes, deposited on ceramic alumina sheet. In the result, it was fabricated sol-gel elastic films of orange dye-sugar blend samples. Two kinds of samples were investigated as temperature sensors: opened surface (1) and encapsulated (2). It was observed that the properties of these samples were entirely different: sample (1) showed positive temperature coefficient, as posistor, whereas sample (2) showed negative temperature coefficient, as thermistor. Temperature coefficient of impedance at 100 Hz of the posistor and thermistor were equal to +150% /degrees C and -9.7% /degrees C, respectively. The transistors can be used as temperature sensors.