Title
Optimization of urea-EnFET based on Ta2O5 layer with post annealing.
Abstract
In this study, the urea-enzymatic field effect transistors (EnFETs) were investigated based on pH-ion sensitive field effect transistors (ISFETs) with tantalum pentoxide (Ta2O5) sensing membranes. In addition, a post N-2 annealing was used to improve the sensing properties. At first, the pH sensitivity, hysteresis, drift, and light induced drift of the ISFETs were evaluated. After the covalent bonding process and urease immobilization, the urea sensitivity of the EnFETs were also investigated and compared with the conventional Si3N4 sensing layer. The ISFETs and EnFETs with annealed Ta2O5 sensing membranes showed the best responses, including the highest pH sensitivity (56.9 mV/pH, from pH 2 to pH 12) and also corresponded to the highest urea sensitivity (61 mV/pC(urea), from 1 mM to 7.5 mM). Besides, the non-ideal factors of pH hysteresis, time drift, and light induced drift of the annealed samples were also lower than the controlled Ta2O5 and Si3N4 sensing membranes.
Year
DOI
Venue
2011
10.3390/s110504562
SENSORS
Keywords
Field
DocType
urea,enzymatic field effect transistor (EnFET),ion sensitive field effect transistor (ISFET),tantalum pentoxide (Ta2O5),post N-2 annealing
Urease,Analytical chemistry,Inorganic chemistry,Hysteresis,Chemistry,Electronic engineering,Membrane,Annealing (metallurgy),Urea,Tantalum pentoxide,Tantalum,Covalent bond
Journal
Volume
Issue
ISSN
11
5
1424-8220
Citations 
PageRank 
References 
2
0.55
1
Authors
5
Name
Order
Citations
PageRank
Cheng-En Lue162.79
Ting-Chun Yu220.55
Chia-Ming Yang3204.79
Dorota G. Pijanowska4158.46
Chao-Sung Lai567.19