Abstract
This work demonstrates an effective approach to improve both charge transport and performance consistency in solution-processed organic thin-film transistors (OTFTs) by blending 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS pentacene, or TP) with a series of small-molecule additives: 4-butylbenzoic acid (BBA), 4-hexylbenzoic acid (HBA), and 4-octylbenzoic acid (OBA). These three small molecules share a benzoic acid moiety, but have different length of hydrophobic tails. The self-assembled interfacial layer of small molecules on the gate oxide surface leads to uniform deposition of TP crystal seeds and facilitates TP to grow along the tilted orientation of substrate, which results in a film of enhanced crystal orientation and areal coverage. OTFTs based on TP/small molecule blends demonstrate greatly improved average hole mobility and performance consistency, which correlates with the length of hydrophobic tail of the small-molecule additives.
| Original language | English |
|---|---|
| Pages (from-to) | 150-155 |
| Number of pages | 6 |
| Journal | Organic Electronics |
| Volume | 15 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 2014 |
Funding
This work was supported by National Science Foundation ( NSF ECCS-1151140 ). A portion of this research was conducted at the Center for Nanophase Materials Sciences and Neutron Scattering Science Division, which are sponsored at Oak Ridge National Laboratory by the Division of Scientific User Facilities , Office of Basic Energy Sciences , U.S. Department of Energy . J.K. acknowledges sample preparation for X-ray reflectivity experiment from Dr. Ming Shao.
Keywords
- Crystal anisotropy
- Interfacial layer
- Organic thin-film transistors
- TIPS pentacene-small molecule blends
- Thin film coverage