title: Fully gravure printed complementary carbon nanotube TFTs for a clock signal generator using an epoxy-imine based cross-linker as an n-dopant and encapsulant.
abstract: Printed p-type single walled carbon nanotube (SWCNT) based circuits exhibit high power dissipation owing to their thick printed dielectric layers (>2 μm) and long channels (>100 μm). In order to reduce the static power dissipation of printed SWCNT-base circuits while maintaining the same printing conditions and channel lengths, complementary metal-oxide-semiconductor (CMOS) based circuits are more ideal. These circuits, however, have not been successfully implemented in a scalable printing platform due to unstable threshold voltages of n-doped SWCNT based thin film transistors (TFTs). In this work, a thermally curable epoxy-imine-based n-doping ink is presented for achieving uniform doping and sealing of SWCNT layers by gravure printing. After printing the n-doping ink, the ink is cured to initiate a cross-linking reaction to seal the n-doped SWCNT-TFTs so that the threshold voltage of the n-doped SWCNT-TFTs is stabilized. Flexible CMOS ring oscillators using such n-doped SWCNT-TFTs combined with the intrinsically p-type SWCNT-TFTs can generate a 0.2 Hz clock signal with significantly lower power consumption compared to similarly printed p-type only TFT based ring oscillators. Moving forward, this CMOS flexible ring oscillator can be practically used to develop fully printed inexpensive wireless sensor tags.
authors.affiliation: Sunchon National University, Printed Electronics Engineering in BK 21 Program, Sunchon, 540-742, Korea. gcho@sunchon.ac.kr.
authors.forename: Donghwan
authors.initials: D
authors.lastname: Kim
authors.affiliation: Sunchon National University, Printed Electronics Engineering in BK 21 Program, Sunchon, 540-742, Korea. gcho@sunchon.ac.kr.
authors.forename: Younsu
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Sunchon National University, Printed Electronics Engineering in BK 21 Program, Sunchon, 540-742, Korea. gcho@sunchon.ac.kr.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Sun
authors.affiliation: Sunchon National University, Printed Electronics Engineering in BK 21 Program, Sunchon, 540-742, Korea. gcho@sunchon.ac.kr.
authors.forename: Chisun
authors.initials: C
authors.lastname: Yeom
authors.affiliation: Sunchon National University, Printed Electronics Engineering in BK 21 Program, Sunchon, 540-742, Korea. gcho@sunchon.ac.kr.
authors.forename: Hyejin
authors.initials: H
authors.lastname: Park
authors.affiliation: Sunchon National University, Printed Electronics Engineering in BK 21 Program, Sunchon, 540-742, Korea. gcho@sunchon.ac.kr.
authors.forename: Dae Gon
authors.initials: DG
authors.lastname: Jung
authors.affiliation: Sunchon National University, Printed Electronics Engineering in BK 21 Program, Sunchon, 540-742, Korea. gcho@sunchon.ac.kr.
authors.forename: Yeonkyeong
authors.initials: Y
authors.lastname: Ju
authors.affiliation: University of California, Berkeley, California 94720, USA. ajavey@berkeley.edu.
authors.forename: Kevin
authors.initials: K
authors.lastname: Chen
authors.affiliation: University of California, Berkeley, California 94720, USA. ajavey@berkeley.edu.
authors.forename: Ali
authors.initials: A
authors.lastname: Javey
authors.affiliation: Sunchon National University, Printed Electronics Engineering in BK 21 Program, Sunchon, 540-742, Korea. gcho@sunchon.ac.kr.
authors.forename: Gyoujin
authors.initials: G
authors.lastname: Cho