Comparison of NH(3) and N(2)O Plasma Treatments on Bi(2)O(3) Sensing Membranes Applied in an Electrolyte–Insulator–Semiconductor Structure

In this study, bismuth trioxide (Bi(2)O(3)) membranes in an electrolyte–insulator–semiconductor (EIS) structure were fabricated with pH sensing capability. To optimize the sensing performance, the membranes were treated with two types of plasma—NH(3) and N(2)O. To investigate the material property improvements, multiple material characterizations were conducted. Material analysis results indicate that plasma treatments with appropriate time could enhance the crystallization, remove the silicate and facilitate crystallizations. Owing to the material optimizations, the pH sensing capability could be greatly boosted. NH(3) or N(2)O plasma treated-Bi(2)O(3) membranes could reach the pH sensitivity around 60 mV/pH and show promise for future biomedical applications.