Observatorio de I+D+i UPM

Descripción
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.
Internacional	Si
JCR del ISI	Si
Título de la revista	Sensors And Actuators B-Chemical
ISSN	0925-4005
Factor de impacto JCR	3,898
Información de impacto	Datos JCR del año 2011
Volumen	176
DOI
Número de revista
Desde la página	704
Hasta la página	707
Mes	SIN MES
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• Autor: Tommaso Brazzini . (UPM)
• Autor: Ana Mª Bengoechea Encabo (UPM)
• Autor: Miguel Angel Sanchez Garcia (UPM)
• Autor: Fernando Calle Gomez (UPM)

• 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