Bottom-up organic integrated circuits
2008 (English)In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 455, no 7215, 956-959 p.Article in journal (Refereed) Published
Self- assembly - the autonomous organization of components into patterns and structures(1) - is a promising technology for the mass production of organic electronics. Making integrated circuits using a bottom- up approach involving self- assembling molecules was proposed(2) in the 1970s. The basic building block of such an integrated circuit is the self- assembled- monolayer field- effect transistor ( SAMFET), where the semiconductor is a monolayer spontaneously formed on the gate dielectric. In the SAMFETs fabricated so far, current modulation has only been observed in submicrometre channels(3-5), the lack of efficient charge transport in longer channels being due to defects and the limited intermolecular pi-pi coupling between the molecules in the self-assembled monolayers. Low field- effect carrier mobility, low yield and poor reproducibility have prohibited the realization of bottom- up integrated circuits. Here we demonstrate SAMFETs with long- range intermolecular pi - pi coupling in the monolayer. We achieve dense packing by using liquid- crystalline molecules consisting of a pi- conjugated mesogenic core separated by a long aliphatic chain from a monofunctionalized anchor group. The resulting SAMFETs exhibit a bulk- like carrier mobility, large current modulation and high reproducibility. As a first step towards functional circuits, we combine the SAMFETs into logic gates as inverters; the small parameter spread then allows us to combine the inverters into ring oscillators. We demonstrate real logic functionality by constructing a 15- bit code generator in which hundreds of SAMFETs are addressed simultaneously. Bridging the gap between discrete monolayer transistors and functional self-assembled integrated circuits puts bottom- up electronics in a new perspective.
Place, publisher, year, edition, pages
Nature Publishing Group , 2008. Vol. 455, no 7215, 956-959 p.
IdentifiersURN: urn:nbn:se:liu:diva-118188DOI: 10.1038/nature07320ISI: 000260038300047OAI: oai:DiVA.org:liu-118188DiVA: diva2:813509
Funding Agencies|Dutch Polymer Institute [project 516]; EU project NAIMO [NMP4-CT-2004-500355]; Dutch Technology Foundation STW; Austrian Science Foundation2015-05-222015-05-222015-06-01