Title :
Charging mechanism of AlGaN/GaN open-gate pH sensor and electrolyte interface
Author :
Anvari, R. ; Myers, M. ; Umana-Membreno, G.A. ; Baker, M. ; Spagnoli, D. ; Parish, G. ; Nener, B.
Author_Institution :
Sch. of Electr., Electron. & Comput. Eng., Univ. of Western Australia, Crawley, WA, Australia
Abstract :
The charging mechanism of the interface between an AlGaN/GaN based open-gate ion-sensitive field-effect transistor and electrolyte is studied theoretically. Density functional theory calculations are performed to obtain the energy minimum structure of the surface oxide and electrolyte interface. Thermodynamics based relations are employed to obtain the double layer parameters. An analytical model is applied to study the carrier density modulation of the AlGaN/GaN heterostrucrure by the influence of the surface charge.
Keywords :
III-V semiconductors; aluminium compounds; carrier density; chemical sensors; density functional theory; electrolytes; gallium compounds; ion sensitive field effect transistors; pH measurement; surface charging; wide band gap semiconductors; AlGaN-GaN; analytical model; carrier density; charging mechanism; density functional theory; double layer parameters; electrolyte; electrolyte interface; energy minimum structure; open-gate ion-sensitive field-effect transistor; open-gate pH sensor; surface oxide; Adsorption; Aluminum gallium nitride; Capacitance; Gallium nitride; Sensitivity; Surface charging; Surface treatment; AlGaN; Density Functional Theory; Electrical Double Layer; GaN; Gallium Oxide; pH sensor;
Conference_Titel :
Optoelectronic and Microelectronic Materials & Devices (COMMAD), 2014 Conference on
Conference_Location :
Perth, WA
Print_ISBN :
978-1-4799-6867-1
DOI :
10.1109/COMMAD.2014.7038679
