Memorias de investigación
Research Publications in journals:
Investigation of AlInN barrier ISFET structures with GaN capping for pH detection
Year:2013

Research Areas
  • Electrochemical,
  • Sensor devices,
  • Other electronic devices

Information
Abstract
The pH response of GaN/AlInN/AlN/GaN ion-sensitive field effect transistor (ISFET) on Si substrates has been characterized. We analyzed the variation of the surface potential (?Vsp/?pH) and current (?Ids/?pH) with solution pH in devices with the same indium content (17%, in-plane lattice-matched to GaN) and different AlInN thickness (6 nm and 10 nm), and compared with the literature. The shrinkage of the barrier, that has the effect to increase the transconductance of the device, makes the 2-dimensional electron density (2DEG) at the interface very sensitive to changes in the surface. Although the surface potential sensitivity to pH is similar in the two devices, the current change with pH (?Ids/?pH), when biasing the ISFET by a Ag/AgCl reference electrode, is almost 50% higher in the device with 6 nm AlInN barrier, compared to the device with 10 nm barrier. When measuring the current response (?Ids/?pH) without reference electrode, the device with thinner AlInN layer has a larger response than the thicker one, of a factor of 140%, and that current response without reference electrode is only 22% lower than its maximum response obtained using reference electrode.
International
Si
JCR
Si
Title
Sensors And Actuators B-Chemical
ISBN
0925-4005
Impact factor JCR
3,898
Impact info
Datos JCR del año 2011
Volume
176
Journal number
From page
704
To page
707
Month
SIN MES
Ranking
Participants

Research Group, Departaments and Institutes related
  • Creador: Grupo de Investigación: Grupo de Dispositivos Semiconductores del ISOM
  • Centro o Instituto I+D+i: Instituto Universitario de Sistemas Optoelectrónicos y Microtecnología
  • Departamento: Ingeniería Electrónica