Block copolymer (BCP) lithography is a powerful technique to write periodic arrays of nanoscale features into substrates at exceptionally high densities. In order to place these features at will on substrates, nanoimprint offers a deceptively clear path toward high throughput production: nanoimprint molds are reusable, promote graphoepitaxial alignment of BCP microdomains within their topography, and are efficiently aligned with respect to the substrate using interferometry. Unfortunately, when thin films of BCPs are subjected to thermal nanoimprint, there is an overwhelming degree of adhesion at the mold-polymer interface, which compromises the entire process. Here we report the synthesis of additives to mitigate adhesion based on either PS or PDMS with short, interface-active fluoroalkyl chains. When blended with PS-b-PDMS BCPs and subjected to a thermal nanoimprint, fluoroalkyl-modified PS in particular is observed to substantially reduce film adhesion to the mold, resulting in a nearly defect-free nanoimprint. Subsequent lithographic procedures revealed excellent graphoepitaxial alignment of sub-10 nm BCP microdomains, a critical step toward lower-cost, high-throughput nanofabrication.
Increasing maturation and dissemination of easy-to-use and affordable means of digital production (e.g. 3D printing), access to these in makerspaces and FabLabs as well as powerful tools and online platforms for virtual and collaborative product design enabled the highly efficient and innovative mode of open source to spill over from software to hardware. Open source technology has enormous potential to spur innovation and enhance technological literacy and thus contribute to socioeconomic and ecological sustainability. Like in software, open source hardware (OSH) projects and online communities have evolved in a broad range of technologies and applications. In these communities, people from all over the world with diverse backgrounds (students, researchers, consumers, users etc.) gather online to jointly develop, revise, improve and freely share hardware designs and documentation. Additionally, people may build, adapt, use and sell physical artefacts based on these designs in accordance with the notion of open source. The (potential) economic impact and value of open source hardware is hard to quantify as contributors usually do not get paid and users do not necessarily buy products from vendors. Nonetheless, value is created as in the case of Linux or Wikipedia. We applied established valuation methods for open source hardware to quantify cost savings and as a result the value of an open source magnetic resonance imaging device (MRI) currently under development by the Open Source Imaging Initiative (OSI 2). Depending on the scenario and the valuation method, we found that savings for healthcare systems from US$1.8 million up to US$222 million per year are possible in the near future making the case for public funding and private investment in open source technology development.
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