Silicon wafers were micropatterned using SU-8 2007 (MicroChem), an epoxy-based photocurable negative-tone photoresist. Silicon wafers were cleaned using acetone, isopropyl alcohol, and deionized water and baked for 10 min at 200°C. A 10-μm-thick layer of SU-8 2007 was deposited onto the wafers by spinning at 1500 rpm, with its thickness verified by white-light interferometry (F20, Filmetrics). Following a preexposure bake at 95°C for 3 min, wafers were exposed to I-line UV (EVG620, EV Group) with a mylar photomask (Fineline) at 140 mJ/cm2. Wafers were then postexposure baked at 95°C for 3 min, developed using an SU-8 developer (MicroChem), and then hard-baked at 200°C for 10 min. We controlled the contact area by decreasing the spacing between circles (s = 24 and 8.7 μm to achieve 30 and 50% of the original contact area, respectively). To avoid fabricating features that were too delicate for use as a mold, the slabs patterned to achieve 30% of the original contact area were composed of individual pillars extending from the surface, whereas the slabs patterned to achieve 50% were composed of an inverse of pillars—a series of wells. These wells are less susceptible to undesirable modes of deformation because they are formed by a single, contiguous network of features, whereas pillars are individual, stand-alone features. Last, to maintain a similar nanoscale roughness between microstructured and flat slabs, both microstructured and flat slabs were cured against the polished surface of a silicon wafer.

Note: The content above has been extracted from a research article, so it may not display correctly.

Please log in to submit your questions online.
Your question will be posted on the Bio-101 website. We will send your questions to the authors of this protocol and Bio-protocol community members who are experienced with this method. you will be informed using the email address associated with your Bio-protocol account.

We use cookies on this site to enhance your user experience. By using our website, you are agreeing to allow the storage of cookies on your computer.