Download 슬라이드 제목 없음 - 나노응용시스템연구센터

Special Issue on the nano devices
서울대 나노 협동과정&
나노 응용시스템 연구센터(NSI_NCRC)
The 5th lecture: MOS as the sensor
Prof. Young June Park
MOSFET Structures and challenges in scaling
Motivation : Other Alternatives
Motivation: Evolution of DG FET(or FINFET)
5nm-Gate Nanowire FinFET
Fu-Liang Yang, et., TSMC group, SOVT 2004
FET as the chemical sensor(with gate)
2 Types: with gate and without gate
-With gate: based on the ISFET structure
changing the charge of the insulator –electrolyte
interface through
: by changing the pH of the electrolyte
or by direct binding of the receptor-molecule binding
-Nanowire
conductor(either silicon or CNT
j
where
l gate is not existent) : in this case,
k potential of the conductor should be stabilized,
surface
or the jconductor should
not be of the surface type device.
Based on ISFET(pH sensitve)
-The interface between the
Insulator and electrolyte
Is modified by the pH of the
Electrolyte ,
which in turn is modulated
by the bio chemical reaction
In the insulator
-In order to achieve better
sensitivity, Al2O3, Si3O4,
or Ta2O5 are used.
ISFET based sensor type 1: Enzyme FET
- Due to the reaction between the enzyme(as the bioreceptor) and the target material,
Products(usually H+) are generated which change the local solution concentration,
which in turn is detected by the ISFET.
•Enzymes are bound to gate insulator through :
-physical or chemical adsorption
-entrapment within polymeric matrices
-cross-linking through cross-linking agents
ISFET based sensor type 1: Cell FET
- Changes monitored by the ISFET
include
Extracellular pH, ion concentration,O2
consumption, CO2production, redox
potential, other metabolic products,
neuronal potentials and others.
-Even the activation of the cell can be
Performed by MOSFET driven electrode.
Based on ISFET: type 2
-The interface between the
Insulator and electrolyte
Is modified by the DNA-DNA
hybridization
or antigen-antibody affinity reaction .
-Potential changes is caused by
surface polarization effects
or through change in dipole moments
Nanowire conductor without gate
-In this case, surface of the FET
(or conductor) should be stabilized
without gate conductor
-Stability of the sensor against the
environment is the challenge.
Nanowire conductor
-Biotin modified nanowires detect
streptavidinbinding at picomolar
concentrations with reversible antibody binding
-To configure nanowire
sensor devices for screening small-molecule inhibitors t
tyrosine kinases, we linked the kinase Abl to the surface
nanowire FETs and investigated the binding of ATP and
competitive inhibition of ATP binding with organic
molecules, such as the drug Gleevec®, as shown
schematically i
Nanowire conductor as the drug discovery
-Even nanowire FET is applied to the drug discovery
by, for example, screening small-molecule inhibitors to
tyrosine kinases.
-Link the kinase Abl to the surface of Si
nanowire FETs and investigated the binding of ATP
And competitive inhibition of ATP binding
with organic molecules,
which is the target materials to find.
i
Fernando Patolsky and Charles M. Lieber*, from April, Materialtoday