TY - JOUR
T1 - Liquid phase sensors based on chemically functionalized GaAs/AlGaAs heterostructures
AU - Luber, S. M.
AU - Adlkofer, K.
AU - Rant, U.
AU - Ulman, A.
AU - Gölzhäuser, A.
AU - Grunze, M.
AU - Schuh, D.
AU - Tanaka, M.
AU - Tornow, M.
AU - Abstreiter, G.
N1 - Funding Information:
The authors thank A. Paul for e-beam cross-linking of some of the MBP samples and M.G. Nikolaides for help with the experimental set-up. This work was financially supported by the DFG (SFB563, Ta 259/1) and in part by Fujitsu Labs Europe.
PY - 2004/3
Y1 - 2004/3
N2 - We report on surface-near two-dimensional electron gases in GaAs/AlGaAs heterostructures for application in potential chemical or biochemical sensors in liquid environment. GaAs cap layers of the heterostructures were coated with self-assembled monolayers of 4′-substituted 4-mercaptobiphenyls (MBP), showing stable device performance in physiological (aqueous) buffers. Deposition of MBP with different 4′-substituents led to systematic changes in the lateral resistance, which can be correlated to the electrical potential drop across the established surface dipole layers. Furthermore, the lateral resistance showed a clear dependency on organic solvents with different polarities, suggesting its high sensitivity to the polarity of physisorbed molecules.
AB - We report on surface-near two-dimensional electron gases in GaAs/AlGaAs heterostructures for application in potential chemical or biochemical sensors in liquid environment. GaAs cap layers of the heterostructures were coated with self-assembled monolayers of 4′-substituted 4-mercaptobiphenyls (MBP), showing stable device performance in physiological (aqueous) buffers. Deposition of MBP with different 4′-substituents led to systematic changes in the lateral resistance, which can be correlated to the electrical potential drop across the established surface dipole layers. Furthermore, the lateral resistance showed a clear dependency on organic solvents with different polarities, suggesting its high sensitivity to the polarity of physisorbed molecules.
KW - GaAs
KW - Heterostructure
KW - Self-assembled monolayer
KW - Sensor
KW - Two-dimensional electron gas
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U2 - 10.1016/j.physe.2003.11.189
DO - 10.1016/j.physe.2003.11.189
M3 - Conference article
AN - SCOPUS:12144288770
SN - 1386-9477
VL - 21
SP - 1111
EP - 1115
JO - Physica E: Low-Dimensional Systems and Nanostructures
JF - Physica E: Low-Dimensional Systems and Nanostructures
IS - 2-4
T2 - Proceedings of the Eleventh International Conference on Modulation (MSS11)
Y2 - 14 July 2003 through 18 July 2003
ER -