Journal: American Chemical Society NANO
Publication date: 2016.10.17
Summarized by Sejin Kim
– The fabrication process of the fully screen-printed flexible active-matrix electrochromic display using SWCNT(single-walled CNT) TFTs.
v. Figure (a)
- High-purity semiconducting SWCNTs were incubated on a 5 × cm2 PET substrate.
- The printing of silver source and drain electrodes and data lines.
- The printing of a BTO layer (barium titanate/gate dielectric) on the channel region of each TFT.
v. Figure (b)
- Printed BTO layer was used as a hard mask for etching to remove the unwanted SWCNTs outside the TFT region.
- Then another BTO layer was printed as a passivation layer to protect the data lines and the ground lines.
v. Figure (c)-(e)
- Scan lines, ground lines, PEDOT:PSS layer, and electrolyte were screen-printed sequentially+.
– The fully screen-printed flexible electrochromic cells.
v. The switching time of this electrochromic cells : 2−5 s
v. The printed EC cell operates reliably under bending.
v. Negligible degradation of the electrical performance after 7 days in air.
– The control of coloration and retention behavior by changing VScan and VData
v. Vscan = -10V [TFT on], VData = 4V: the oxidation of PEDOT:PSS-> [transparent state]
v. Vscan = 10V [TFT off], VData = 4V: the pixel color is retained.
v. Vscan = -10V [TFT on], VData = -4V à the reduction of PEDOT:PSS -> [dark-blue state]
v. Vscan = 10V [TFT off], VData = – 4V: the pixel color is retained.