TY  - JOUR
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Reisert, Steffen
A1  - Kramer, Friederike
A1  - Begoyan, Vardges K.
A1  - Buniatyan, Vahe V.
A1  - Schöning, Michael Josef
T1  - Multi-parameter sensing using high-k oxide of barium strontium titanate
JF  - Physica status solidi (a)
N2  - High-k perovskite oxide of barium strontium titanate (BST) represents a very attractive multi-functional transducer material for the development of (bio-)chemical sensors. In this work, a Si-based sensor chip containing Pt interdigitated electrodes covered with a thin BST layer (485 nm) has been developed for multi-parameter chemical sensing. The chip has been applied for the contactless measurement of the electrolyte conductivity, the detection of adsorbed charged macromolecules (positively charged polyelectrolytes of polyethylenimine) and the concentration of hydrogen peroxide (H2O2) vapor. The experimental results of functional testing of individual sensors are presented. The mechanism of the BST sensitivity to charged polyelectrolytes and H2O2 vapor has been proposed and discussed.
Y1  - 2015
U6  - https://doi.org/10.1002/pssa.201431911
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1259
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Özsoylu, Dua
A1  - Kizildag, Sefa
A1  - Schöning, Michael Josef
A1  - Wagner, Torsten
T1  - Effect of plasma treatment on the sensor properties of a light‐addressable potentiometric sensor (LAPS)
JF  - physica status solidi a : applications and materials sciences
N2  - A light-addressable potentiometric sensor (LAPS) is a field-effect-based (bio-) chemical sensor, in which a desired sensing area on the sensor surface can be defined by illumination. Light addressability can be used to visualize the concentration and spatial distribution of the target molecules, e.g., H+ ions. This unique feature has great potential for the label-free imaging of the metabolic activity of living organisms. The cultivation of those organisms needs specially tailored surface properties of the sensor. O2 plasma treatment is an attractive and promising tool for rapid surface engineering. However, the potential impacts of the technique are carefully investigated for the sensors that suffer from plasma-induced damage. Herein, a LAPS with a Ta2O5 pH-sensitive surface is successfully patterned by plasma treatment, and its effects are investigated by contact angle and scanning LAPS measurements. The plasma duration of 30 s (30 W) is found to be the threshold value, where excessive wettability begins. Furthermore, this treatment approach causes moderate plasma-induced damage, which can be reduced by thermal annealing (10 min at 300 °C). These findings provide a useful guideline to support future studies, where the LAPS surface is desired to be more hydrophilic by O2 plasma treatment.
Y1  - 2019
U6  - https://doi.org/10.1002/pssa.201900259
SN  - 1862-6319
N1  - Corresponding author: Torsten Wagner
VL  - 216
IS  - 20
PB  - Wiley
CY  - Weinheim
ER  -