10.1021/ja901619h.s001
Meng-Hsien Lin
Meng-Hsien
Lin
Chi-Fan Chen
Chi-Fan
Chen
Hung-Wei Shiu
Hung-Wei
Shiu
Chia-Hao Chen
Chia-Hao
Chen
Shangjr Gwo
Shangjr
Gwo
Multilength-Scale Chemical Patterning of Self-Assembled Monolayers by Spatially Controlled Plasma Exposure: Nanometer to Centimeter Range
American Chemical Society
2009
contact masks
SAM
chemical patterning method
XPS
PDMS
monolayer
SPEM
Centimeter RangeWe
photoelectron
contact angle measurements
scanning Kelvin probe microscopy
colloid nanoparticles
SEM
air plasma causes hydroxylation
channel stamps
SKPM
surface functionalities
chemical conversion method
Spatially Controlled Plasma Exposure
feature sizes
50 nm range
plasma exposure
methyl terminal group
carboxyl groups
OTS
2009-08-12 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Multilength_Scale_Chemical_Patterning_of_Self_Assembled_Monolayers_by_Spatially_Controlled_Plasma_Exposure_Nanometer_to_Centimeter_Range/2835784
We present a generic and efficient chemical patterning method based on local plasma-induced conversion of surface functional groups on self-assembled monolayers (SAMs). Here, spatially controlled plasma exposure is realized by elastomeric poly(dimethylsiloxane) (PDMS) contact masks or channel stamps with feature sizes ranging from nanometer, micrometer, to centimeter. This chemical conversion method has been comprehensively characterized by a set of techniques, including contact angle measurements, X-ray photoelectron spectroscopy (XPS), scanning photoelectron microscopy (SPEM), scanning electron microscopy (SEM), and scanning Kelvin probe microscopy (SKPM). In particular, XPS and SPEM can be used to distinguish regions of different surface functionalities and elucidate the mechanism of plasma-induced chemical conversion. In the case of an octadecyltrichlorosilane (OTS) monolayer, we show that exposure to low-power air plasma causes hydroxylation and oxidation of the methyl terminal group on an OTS-covered Si surface and generates polar functional groups such as hydroxyl, aldehylde, and carboxyl groups, which can allow subsequent grafting of dissimilar SAMs and adsorption of colloid nanoparticles onto the patterned areas with an achievable resolution down to the 50 nm range.