Influence of Low Molecular Weight PDMS Chains in PDMS-Based Non-Photolithography
- PDF / 183,502 Bytes
- 5 Pages / 612 x 792 pts (letter) Page_size
- 5 Downloads / 168 Views
0921-T06-03
Influence of Low Molecular Weight PDMS Chains in PDMS-Based Non-Photolithography Jinook Kim1, C. H. Lee1, Mikyung Park1, G. S. Chae1, In-Jae Chung1, and Jinook Kim2 1 LG.Philips LCD R&D Center, Anyang-shi, Gyongki-do, 431-080, Korea, Republic of 2 LG.Philips LCD R&D Center, Anyang-shi, 431-080, Korea, Republic of
ABSTRACT We describe that an elastomeric stamp of poly(dimethylsiloxane) (PDMS) can modify the surface energy of some surfaces when brought into conformal contact with the number of stamping. We focus on an increase of the hydrophobicity of the patterned surface due to diffusion of low molecular weight (LMW) silicone polymer chains. The transfer of PDMS to the surface during patterning is relevant to and calls for attention by those who are using this method in applications where control of the surface chemistry is of importance for the application. INTRODUCTION Siloxane-based elastomers have found widespread use as sealants, for encapsulation and packaging of electronic components [1], and, most recently, for soft lithography [2]. In soft lithography, the relief structure of a stamp is used to form desired pattern. The most important tool used in soft lithographic techniques is a transparent elastomeric poly(dimethylsiloxane) (PDMS). PDMS is very soft (Young’s modulus ~ 2 Mpa), low surface energy (~ 20 mJ/m2), chemically cross-linked rubber, which easily established conformal contact with a substrate and exhibits excellent printing (for example, micro-contact printing) characteristics with inks. The conformal contact between the stamp and the surface is ascertained by the interfacial force and flexibility of the stamp material. A matter of concern, in some situations where non-conventional lithography with contact process between patterned surface and a PDMS stamp is used, is the risk of the transfer of uncured or low molecular weight molecules/oligomers from stamp to the patterned surface. Recent work [3] suggests that organic light-emitting diodes (OLEDs) formed by soft-contact lamination using a PDMS stamp of metal electrodes to form organic electroluminescent (EL) layers. Virtually, the OLEDs had a double cathode device for the efficiency or lifetime of the device [4]. Thus, when metal are deposited on a contaminated surface with un-cured PDMS chains, the resulting degradation of the metal substrates caused film delamination or diffusion into the patterned metal layer, which produced surfaces to which deposited films do not adhere, laminate, or wet. In this article, we demonstrate that a surface can be changed by PDMS-based lithography and suggest the role that the ink design plays in non-photolithography with contact between the PDMS stamp and ink.
EXPERIMENTAL DETAILS The PDMS stamps were prepared by casting the PDMS precursor (Sylgard 184, Dow Corning) on the substrates with a curing agent in the ratio of 10 to 1 against the masters prepared by photolithography and curing at several temperature (from 80 to 230 °C) for 1 h. Soft UVimprinting was used PDMS stamp cured at 80 °C for 1 h.
Data Loading...
