Deposition andin-situ plasma doping of plasma-polymerized thiophene films using PECVD

Abstract

Highly transparent, thin polythiophene (PT) films were successfully synthesized by the plasma polymerization of thiophene. These films were doped with O 2 plasma by in-situ doping technique. The plasma polymerized PT films were deposited at about 50 to 340 nm/min, depending on the temperature and plasma power. A resultant transparency as high as 85% was achieved. The plasma polymerized PT films exhibited the characteristics of an insulator or semiconductor (10 1 0 ~ 1 2 Ω/̱ , 10 -7S/cm). The conductivity was immediately increased up to 10 Ω/̱ and 10 -2 S/cm, when doped with O 2 plasma. The plasma-doped PT films exhibited an increased surface roughness resulting in a decreased contact angle. However, the thickness of the PT layer was partially decomposed and/or etched with increasing voltage above 40 W.

Chemical Vapor Deposition of Conformal, Functional, and Responsive Polymer Films

“…PECVD has been used in conjunction with thiophene (and its derivatives),124–135 pyrrole,121, 133, 136 and aniline137–139 monomers. Both the chemical structure and properties of the PECVD films differ from the conducting polymers obtained by traditional wet‐synthetic methods and are dependent on the plasma‐polymerization conditions.…”

Plasma deposition of organic polymer films for solar cell applications

“…Thiophene was chosen as one of the organic precursors because it was examined previously in conductivity measurements after doping. [18,19] However, in these cases, plasma deposition of thiophene produced films that were partially oxidized and highly crosslinked. 4-Methylthiazole was chosen as a nitrogen-…”

“…There are only a few studies in the literature that used plasma deposited polymeric materials for electronic applications. [16][17][18][19][20][21] The majority of these studies were focused on the conducting properties of doped films. Investigations into semiconducting properties of plasma deposited organic films has been rare.…”

In-Situ Iodine Doping Characteristics of Conductive Polyaniline Film Polymerized by Low-Voltage-Driven Atmospheric Pressure Plasma

“…By contrast, in-situ I 2 doping is an in-line processing method that is highly suitable for plasma polymerization in which nucleation reaction and crosslinking occur in the gas phase. Nevertheless, in sharp contrast to the many studies on the use of in-situ doping in the vacuum plasma process [ 42 , 43 , 44 ], there are only a few studies related to the use of in-situ doping in atmospheric pressure plasma polymerization. This is because the discharge becomes unstable due to dopant injection, which adversely affects plasma polymerization steps such as the fragmentation, recombination, and nucleation of monomers.…”