Nano-textured high sensitivity ion sensitive field effect transistors

Journal Article · Sun Feb 07 04:00:00 EST 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4940915· OSTI ID:22494976

Hajmirzaheydarali, M.; Sadeghipari, M.; Akbari, M.; Shahsafi, A.

Nano-textured gate engineered ion sensitive field effect transistors (ISFETs), suitable for high sensitivity pH sensors, have been realized. Utilizing a mask-less deep reactive ion etching results in ultra-fine poly-Si features on the gate of ISFET devices where spacing of the order of 10 nm and less is achieved. Incorporation of these nano-sized features on the gate is responsible for high sensitivities up to 400 mV/pH in contrast to conventional planar structures. The fabrication process for this transistor is inexpensive, and it is fully compatible with standard complementary metal oxide semiconductor fabrication procedure. A theoretical modeling has also been presented to predict the extension of the diffuse layer into the electrolyte solution for highly featured structures and to correlate this extension with the high sensitivity of the device. The observed ultra-fine features by means of scanning electron microscopy and transmission electron microscopy tools corroborate the theoretical prediction.

• OSTI ID: 22494976
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 5 Vol. 119; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ETCHING
FABRICATION
FIELD EFFECT TRANSISTORS
IONS
NANOSTRUCTURES
SCANNING ELECTRON MICROSCOPY
SEMICONDUCTOR MATERIALS
SENSITIVITY
SENSORS
TRANSMISSION ELECTRON MICROSCOPY