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Title: Reducing the Barrier Height in Organic Transistors
Abstract Reducing the Schottky barrier height and Fermi level de‐pinning in metal‐organic semiconductor contacts are crucial for enhancing the performance of organic transistors. The reduction of the Schottky barrier height in bottom‐contact top‐gate organic transistors is demonstrated by adding 1 nm thick atomic layer deposited Al2O3on the source and drain contacts. By using two different donor‐acceptor copolymers, bothp‐andn‐type transistors are investigated. Temperature‐dependent current–voltage measurements from non‐treated, self‐assembled monolayer treated, and Al2O3treated Au source‐drain contact field‐effect transistors with varying channel lengths are carried out. The drain current versus drain voltage near zero gate voltage, which may be described by the thermionic emission model at temperatures above 150 K, allows the estimation of the Schottky barrier height (φB). The Al2O3contact‐treated transistors show more than 40% lowerφBcompared with the non‐treated contacts in thep‐type transistor. Similarly, an isoindigo‐based transistor, withn‐type transport, shows a reduction inφBwith Al2O3treated contacts suggesting that such ultrathin oxide layers provide a universal method for reducing the barrier height.  more » « less
Award ID(s):
2324839
PAR ID:
10617381
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Electronic Materials
Volume:
11
Issue:
4
ISSN:
2199-160X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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