Investigation of the dependence of sheet resistance on the thickness of spin coated poly (3-Hexylthiophene) thin films
Loading...
Date
2024
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Namibia
Abstract
Sheet resistance (R□) and thickness of as-cast and post-treated poly(3-
hexylthiophene) (P3HT) thin films fabricated on non-conductive glass substrates by
the spin coating method, were determined under dark, and illuminated conditions. R□
of P3HT thin films of different thicknesses were compared, to examine the effect of
illumination on the R□, and hence on the resistivity of the films. Commercially
available P3HT was purchased and dissolved in chloroform (CHCl3). Glass slides
were cleaned using detergent, acetone, and alcohol, in an ultrasonic bath, followed
by cleaning in distilled water. P3HT thin films were fabricated by spin coating
CHCl3 based solutions on cleaned, dry glass substrates, in ambient air. The films
were annealed at a controlled temperature, and then the R□ of each thin film was
measured, using the in-line four-point probe method. The thicknesses of the thin
films were varied by varying the spin speed (ω) of the spin coater. The results
showed a correlation between the R□ and the P3HT thin films’ thickness. The R□
reduces as the thicknesses of the P3HT thin films increase in the light, and in the
dark, for as-cast, and annealed, P3HT thin films. Annealing also reduced the R□ of
the P3HT thin films, and R□ showed some reductions when measured in the dark.
The four-point probe method can be used to characterise materials
Description
A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science (Physics)
Keywords
P3HT, Sheet resistance, Spin coating, Thin films, Annealing, Four-point probe method