High-$\kappa$ field-effect transistor with copper-phthalocyanine

TL;DR

This study demonstrates high-permittivity SrTiO₃ dielectrics enabling low-voltage, p-type organic FETs with copper-phthalocyanine, achieving notable mobility and on/off ratios in a vacuum fabrication process.

Contribution

First demonstration of high-$5$ dielectric SrTiO₃ in organic FETs with in-situ fabrication, achieving low-voltage operation and competitive performance.

Findings

Permittivity of SrTiO₃ up to 200.

Low driving voltage of 3 V.

Mobility of about 1.5×10⁻³ cm²/Vs and on/off ratio of 10³.

Abstract

The use of SrTiO$_3$ dielectrics as high-permittivity insulator in organic thin film field effect transistors (FET) is evaluated. Field-effect transistors with sputtered SrTiO$_3$ and copper-phthalocyanine (CuPc) as semiconducting layer were fabricated. The device preparation was performed in-situ in an ultra high vacuum chamber system. The dielectric in the transistors had a permittivity of up to 200 which led to low driving voltages of 3 V. The field effect transistors were p-type and reached mobilities of about $\mu = 1.5\times 10^{-3}$ cm$^2$/Vs and an on/off ratio of $10^3$. These properties are compared to devices based on other dielectric materials.