Yoshihiro Saida

Evaluation of electrochromic fast-switching behavior of self-doped conducting polymer

Abstract The electrochemical and optical fast-switching behavior of a self-doped conducting polymer was investigated by cyclic voltammetry and opto-electrochemical spectroscopy. In comparison with poly(3-hexylthiophene), the self-doped polymer thin film exhibited a reasonable electrochemical response in an acid electrolyte solution, even at fast scan rates. The optical switching phenomenon on the self-doped polymer was observed to take place within about 50 ms, in contrast to polyisothianaphthene which exhibits optical switching within about 500 ms.

A facile preparation of a self-doped conducting polymer

A self-doped conducting polymer having alkanesulphonic acid groups on polythiophene has been directly synthesized from sodium 3-(3-thienyl)propanesulphonate 3 by chemical polymerization with FeCl3 in an aqueous medium; the resulting acid form of this polymer after work-up shows highly self-doped behaviour both in water and as a solid film and has a high molecular weight distribution.

Evaluation of the new-type ESPACER adopted for its removal after Post-Exposure Bake Process

The second level exposure of Alternating Phase Shift Mask has to be accomplished by e-beam lithography. However, e-beam writing on structured open chrome layers may induce severe charging and yields to deteriorate overlay accuracy. In case of charging problems, applying of conductive top coats on resists help to reduce the distortion of the second layer. ESPACER makes the conductive layer on the e-beam resist and prevent a positioning error during e-beam writing by its shield effect. However, ESPACER required removal of its topcoat before post-exposure bake (PEB) because of the undesirable effect to the resist, due to the acid diffusion from the ESPACER film to high sensitive Chemical Amplified Resists (CARs). Our investigations were focused on the combination of the representative positive tone CAR: FUJIFILM ELECTRONIC MATERIALS CO., LTD and the new-type ESPACER called ESPACER 300F. ESPACER 300F was possible to use the PEB process before its removal, improved by exchanging a lower mobility surfactant than before. This material also had a good wettability, a low resist-thickness losses and kept good pattern shapes of the resist. Additionally, ESPACER 300F have little influence in both overlay accuracy at the variety of pattern density and sensitivity of the resist, therefore it would be the good material for making reticles for 65nm node and beyond.