Journal of Biotechnology & Biomaterials
Open Access

Abstract

State-of-the-art carriers for biosensors, tissue engineering, and directed cell growth are chemically functionalized and coated by polymers to operate under physiological conditions. There is still a strong demand for the development of smart carriers with high accuracy, selectivity, lower detection limits and robustness during autoclaving for sterilization, incubation for cell growth, and cryogenic applications for shock freezing. We have implanted ions in ca. 200 - 1000 nm thick layers of semiconductor wafers, in order to realize defined microscopic to nanoscopic patterns of surface-near electrostatic forces (SNEF). Finally, these charge patterned silicon wafers are protected by a thin 2-3 nm thick insulting oxide layer. The estimated density of localized charges between the native silicon dioxide and the silicon carrier ranges from 1014 to 1018 m-2 and is much larger and stable than charges from silanol groups at an ordinary silicon dioxide surface. Using combined Atomic and Kelvin probe force microscopy measurements (KPFM), we could prove that positively and negatively charged polymers are preferentially adsorbed at n-type and p-type conducting regions of the of locally implanted silicon carrier with different SNEF patterns. Moreover from KPFM measurements, we know that the SNEF can be minimized by applying an appropriate bias to correspondingly structured back electrodes.

Biography

Heidemarie Schmidt has completed her PhD at the University Leipzig. Since 2003, she and her team from the “Nano-Spintronics” group has been developing new materials for neuromorphic computing, transparent spintronics, magnetooptics, and for smart carriers in biotechnology at the University Leipzig, HZDR, and TU Chemnitz. She has published more than 150 papers in reputed journals and serves as an advisory program committee member for the international workshop in Ellipsometry WSE-2014 and WSE-2015. She received the Nano-Future prize from the Bundesministerium für Bildung und Forschung (2002) and a Heisenberg Fellowship from the German Science foundation (2011).

Email: Heidemarie.Schmidt@etit.tu-chemnitz.de