Enhanced conductivity of Y-doped ZnO thin films by incorporation of multiple walled carbon nanotubes

Multiple walled carbon nanotubes have been incorporated into yttrium-doped zinc oxide (YZO) films through sol-gel method. Sol-gel process is used since it is an inexpensive means of thin film deposition when compared to the more expensive and time consuming techniques like RF sputtering. The structural, electrical and optical properties of the YZO films with and without multiple walled carbon nanotubes (MWCNT) are investigated. The carrier concentration of YZO/MWCNT composite films (2.95 × 10¹⁹ cm^{- 3}) is found to be twice that of the YZO films (1.49 × 10¹⁹ cm ^{- 3}) achieving lower electrical resistivity of 4.36 × 10 ^{- 2} Ω-cm and an optical transparency over 85% making it suitable for application as channel injection layer in transparent organic thin film transistors. The spin coating or printable procedure of the solution processed YZO/MWCNT for incorporating a channel injection layer can replace expensive vacuum processes techniques.