Teräs alustamateriaalina/ steel as a substrate
Teräs soveltuu erinomaisesti painetun elektroniikan rungoksi. Sen lujuus ja jäykkyys ovat suuret ja sen joustavuus/ taivutettavuus riittää useimpiin sovelluksiin. Se toimii sulkuna (happi, vesihöyry) ja kilpailee siinä lasin kanssa. Se ei ole läpinäkyvää.OLEDejä ryhdytään valmistamaan teräspohjalle:
http://www.printedelectronicsnow.com/contents/view_breaking-news/2017-09-22/oleds-applied-to-paper-thin-stainless-steel
09.22.17
Fraunhofer Institute FEP, the Nippon Steel & Sumikin Materials Co., Ltd. (NSMAT) and Nippon Steel & Sumitomo Metal Corporation (NSSMC) > will be presenting OLEDs on gauzy stainless steel foil.
Ruostumatonta terästä on vuosia käytetty ohtkalvoaurinkokennoissa ja paristoissa. Nyt niitä sovelletaan joustavan elektroniikan komponenteissa.
"Stainless steel foil has also been utilized for several years in thin-film photovoltaics and batteries. Now stainless steel can also serve as a substrate for flexible electronic components. In comparison to the conventional substrate materials like glass or plastic web the material possesses special properties for this purpose and is well-suited as a substrate for organic light-emitting diodes (OLEDs), for example. With the planarization layer *) as well as the comparatively good thermal conductivity of stainless steel, homogenous large-area lighting surfaces with current densities of more than 10 mA/cm² have become better applicable."
"OLEDs need to be protected from water vapor and oxygen in order that the organic layers remain fully functional. Stainless steel provides excellent barrier properties against environmental influences and is therefore suitable as a substrate for OLEDs from this standpoint as well. 'We see OLEDs on stainless steel in perhaps three years from now being used in automobiles as turn indicator and back-up lights, as cladding for fascia, and as advertising displays.' Fraunhofer FEP has at its disposal roll-to-roll processing lines for manufacturing OLEDs on flexible materials and an OLED process that has high reproducibility. This is what has made possible the development of stainless steel foil with a clean and smooth planarization layer."
Teräsnauhan pinnankarheus on liian suuri hienoja, ohuita piirejä painettaessa ja siksi pintaa joudutaan tasoittamaan ylimääräiselä pinnoitteella.
https://www.quizover.com/course/section/bibliography-applications-for-silica-thin-films-by-openstax
*) Schematic representation of the planarization process. A metallization feature (a) is CVD covered with silicate glass (b), and subsequently coated with an organic resin (c). After etching the resist a smooth silicate surface is produced (d).
The processes of planarization is vital for the development of multilevel structures in VLSI circuits. To minimize interconnection resistance and conserve chip area, multilevel metallization schemes are being developed in which the interconnects run in 3-dimensions.
http://www.nssmc.com/tech/report/nssmc/pdf/117-06.pdf
Teräsnauha-aihion pinnoittaminen tasoittavalla kerroksella.
"There exists fine ruggedness of a number of rolled-in streaks on the surface of the stainless steel foil. Since the thickness of each layer constituting an electronics device is of nanometer order, in order to deposit each film layer without it being broken, the surface of the stainless steel foil needs to be planarized to the level of a glass substrate."
