Improved performance of n-type organic field-effect transistor with a non-conjugated polyelectrolyte layer

We characterized the n-type organic field-effect transistors (OFETs) with non-conjugated polyelectrolytes (NPEs) interlayers as the electron injection layer. Novel NPEs with various ions (Cl-, Br-, I-) improved the electron mobility from $5.06{\times}10^{-3}$ to $2.10{\times}10^{-2}cm^2V^{-1}s^{-1}$ in OFETs based [6,6]-Phenyl-$C_{61}$-butyric acid methyl ester (PCBM) when $PEIEH^+I^-$ spin-cast from 0.6% solution was deposited onto the PCBM layer. Reduced electron injection barrier (${\phi}_e$) at NPE/metal electrode interface was induced by dipole formation and led to increase the electron injection and transport. These findings are important for understanding how NPEs function in devices, the improvement of device performance, and the design of new materials for use in optoelectronic devices.