Temperature characteristics of a-Si : H gate ISFET

In this paper, we put emphasis on the study of the temperature effect of th e ISFET (ion sensitive field effect transistor) based on the hydrogenated a morphous silicon (a-Si:H). Since the temperature influences the properties of the ISFET device, we studied the influence of the temperature effect to ISFET in detail. In this paper, we prepared the a-Si:H/SiO2/p-Si/Al structu re of ISFET devices by plasma-enhanced chemical vapor deposition (PECVD). T he thickness of the a-Si:H was 2000 Angstrom. Then we used epoxy to encapsu late the a-Si:H pH-ISFET device. Furthermore, we utilized Keithley 236 Semi conductor Parameter Analyzer to measure the I-V curve, and then pH sensitiv ity of the a-Si:H pH-ISFET was determined. Since the a-Si:H thin film is ea sily dissolved in alkaline solution, so it was measured in acid solutions b etween pH 1-7. The experimental results were also compared with the simulat ed results. We can conclude that the experimental results approximately agr ee with simulation results. (C) 2001 Elsevier Science B.V. All rights reser ved.