Abstract
| Original language | English |
|---|---|
| Title of host publication | Microfluidics, BioMEMS, and Medical Microsystems VIII |
| Place of Publication | USA |
| Publisher | International Society for Optics and Photonics SPIE |
| DOIs | |
| Publication status | Published - 2010 |
| MoE publication type | Not Eligible |
| Event | Microfluidics, BioMEMS, and Medical Microsystems VIII, SPIE MOEMS-MEMS, 2010 - San Francisco, United States Duration: 25 Jan 2010 → 27 Jan 2010 |
Publication series
| Series | Proceedings of SPIE |
|---|---|
| Number | 7593 |
Conference
| Conference | Microfluidics, BioMEMS, and Medical Microsystems VIII, SPIE MOEMS-MEMS, 2010 |
|---|---|
| Abbreviated title | SPIE MOEMS-MEMS, 2010 |
| Country | United States |
| City | San Francisco |
| Period | 25/01/10 → 27/01/10 |
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PDMS surface modification in the application of waveguide claddings for evanescent field sensing. / Meng, Wang; Uusitalo, Sanna; Myllylä, R.; Hakalahti, Leena; Känsäkoski, Markku.
Microfluidics, BioMEMS, and Medical Microsystems VIII. USA : International Society for Optics and Photonics SPIE, 2010. 759317 (Proceedings of SPIE; No. 7593).Research output: Chapter in Book/Report/Conference proceeding › Conference article in proceedings › Scientific › peer-review
TY - GEN
T1 - PDMS surface modification in the application of waveguide claddings for evanescent field sensing
AU - Meng, Wang
AU - Uusitalo, Sanna
AU - Myllylä, R.
AU - Hakalahti, Leena
AU - Känsäkoski, Markku
PY - 2010
Y1 - 2010
N2 - We fabricated SU-8 based slab waveguides on surface-modified poly(dimethyl siloxane) PDMS lower claddings for application in evanescent field sensing. In this application, higher sensitivity is obtained by generating stronger penetrating power above the waveguide into the analyte. This can be achieved by reducing the refractive index of the substrate. Compared with glass substrates that have a refractive index of 1.5, PDMS has a refractive index of 1.42 at 633 nm, thus serving as a better lower cladding material for high-sensitivity sensing with an evanescent field or as claddings in multilayer waveguide applications. In order to increase the adhesion of PDMS surfaces for successful SU-8 application we treated PDMS thin films in low-frequency (40 kHz) oxygen plasma for varied length of exposure time. The treatment process made PDMS hydrophilic and created nano-structures on the surfaces. The resultant surface topography with different exposure time was studied by an interferometric profiler on PDMS lower claddings and the later spin-coated SU-8 waveguides. Measurement results showed that longer plasma treatment on PDMS claddings significantly improved the uniformity and waviness of the waveguides. Light propagation tests performed with a prism coupler and an end-butt coupling setup proved that PDMS can be used as a proper material for SU-8 waveguides.
AB - We fabricated SU-8 based slab waveguides on surface-modified poly(dimethyl siloxane) PDMS lower claddings for application in evanescent field sensing. In this application, higher sensitivity is obtained by generating stronger penetrating power above the waveguide into the analyte. This can be achieved by reducing the refractive index of the substrate. Compared with glass substrates that have a refractive index of 1.5, PDMS has a refractive index of 1.42 at 633 nm, thus serving as a better lower cladding material for high-sensitivity sensing with an evanescent field or as claddings in multilayer waveguide applications. In order to increase the adhesion of PDMS surfaces for successful SU-8 application we treated PDMS thin films in low-frequency (40 kHz) oxygen plasma for varied length of exposure time. The treatment process made PDMS hydrophilic and created nano-structures on the surfaces. The resultant surface topography with different exposure time was studied by an interferometric profiler on PDMS lower claddings and the later spin-coated SU-8 waveguides. Measurement results showed that longer plasma treatment on PDMS claddings significantly improved the uniformity and waviness of the waveguides. Light propagation tests performed with a prism coupler and an end-butt coupling setup proved that PDMS can be used as a proper material for SU-8 waveguides.
U2 - 10.1117/12.841244
DO - 10.1117/12.841244
M3 - Conference article in proceedings
T3 - Proceedings of SPIE
BT - Microfluidics, BioMEMS, and Medical Microsystems VIII
PB - International Society for Optics and Photonics SPIE
CY - USA
ER -