Polycrystalline silicon ion sensitive field effect transistors

Abstract

We report the operation of polycrystalline silicon ion sensitive field effect transistors. These devices can be fabricated on inexpensive disposable substrates such as glass or plastics and are, therefore, promising candidates for low cost single-use intelligent multisensors. In this work we have developed an extended gate structure with a Si 3 N 4 sensing layer. Nearly ideal pH sensitivity �54 mV/ pH� and stable operation have been achieved. Temperature effects have been characterized. A penicillin sensor has been fabricated by functionalizing the sensing area with penicillinase. The sensitivity to penicillin G is about 10 mV/ mM, in solutions with concentration lower than the saturation value, which is about 7 mM.

Highly sensitive dopamine biosensors based on organic electrochemical transistors

“…Transistors have shown important applications in labelfree and high-sensitivity detection of biomolecules including antigen-antibody (Stern et al, 2007), DNA ), protein (Estrela et al, 2010Kanungo et al, 2002), enzyme (Yan et al, 2005), cells (Patolsky et al, 2006), etc. Organic electrochemical transistors (OECTs), as one type of OTFT, have attracted much attention in the past decades because the devices can be used in aqueous solutions with very stable performance and low operating voltages (∼1 V) (White et al, 1984;Bernards and Malliaras, 2007;Berggren and Richter-Dahlfors, 2007;Lin et al, 2010a).…”

Highly photosensitive thin film transistors based on a composite of poly(3-hexylthiophene) and titania nanoparticles

“…It has been recognized that thin film transistors offer a great deal of promise for applications in various types of sensors, including light sensor, 2,3 pressure sensor, 4 gas sensor, 5 and chemical, biological, and medical sensors. [6][7][8][9] Miniaturization is demanded for all types of sensors because of the need for better portability, higher sensitivity, lower power dissipation, and better device integration. OTFTs can be miniaturized without a reduction in signal to noise ratio since the channel current is not directly related to the area but to the ratio between the channel width and length of the device.…”

Chemical and Biological Field‐Effect Sensors for Liquids—A Status Report

“…Generally, the following basic mechanisms of potential generation can be considered: a pH or ion-concentration change, enzymatic reactions, adsorption of charged macromolecules (e.g., polyelectrolytes, deoxyribonucleic acid (DNA)), affinity binding of molecules (e.g., antigen-antibody affinity reaction, DNA hybridization), and potential changes that are coming from living biological systems as a result of more sophisticated (bio-)chemical processes (e.g., action potentials of nerve cells). [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] However, sometimes these results have been "rediscovered" from results that have already been obtained more than 10-30 years ago. At present, Si 3 N 4 , Al 2 O 3 , and Ta 2 O 5 serve as pH-sensitive gate insulator materials in commercial ISFETs.…”