Solution-Processed and Self-Assembled Monolayer-Treated High-Voltage Organic Thin Film Transistors for Flexible MEMS Int
- PDF / 1,352,188 Bytes
- 6 Pages / 432 x 648 pts Page_size
- 66 Downloads / 178 Views
MRS Advances © 2018 Materials Research Society DOI: 10.1557/adv.2018.41
Solution-Processed and Self-Assembled MonolayerTreated High-Voltage Organic Thin Film Transistors for Flexible MEMS Integration Andy Shih1 and Akintunde Ibitayo Akinwande1 1 Department of Electrical Engineering and Computer Science, Microsystems Technology Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, U.S.A., email: [email protected]
ABSTRACT
We report a 6,13-Bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) solution-processed high-voltage organic thin film transistor (HVOTFT) with a large breakdown voltage of |V DS| > 450 V, a three-fold increase from previous results. An offset channel architecture and an organosilane-based self-assembled monolayer (SAM) treatment were used to achieve large breakdown voltages. Solution-processed HVOTFTs will enable novel high-voltage and flexible applications. Reliability of the HVOTFT under high-field stress was studied in the context of threshold and onset to conduction voltages.
INTRODUCTION The desire to explore electronics on arbitrary and flexible surfaces has led to the development of organic semiconductors with solution-processing ability, low processing cost and mechanical flexibility [1]. Although transport properties of organic thin film transistors (OTFTs), as measured by mobility, are comparable to hydrogenated amorphous Si (a-Si:H) thin film transistors (TFTs), there are currently very few efforts to broaden their performance to include large drive voltages. Of particular interest is the ability of a solution-processed high-voltage organic thin film transistor (HVOTFT) to drive voltages above 100 V across its drain and source (V DS) while operating under a low gate to source voltage (VGS). High-voltage in TFTs allows for novel applications such as photovoltaic systems on glass (PV-SOG) and flat-panel detectors for digital x-ray imaging [2, 3]. Another application of great interest is the integration of the HVOTFT with large electrostatic MEMS actuators on arbitrary and flexible substrates, where large drive voltages are desired over large drive currents [4]. Over the past years, OTFT research has focused on low voltage applications, typically operating well below 50 V [5]. Our previous work on pentacene and 6,13Bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) HVOTFTs had high-voltage capabilities up to 550 and 150 V, respectively [6]. Furthermore, a-Si high-voltage thin film transistors (HVTFTs) have been shown to actuate MEMS cantilevers with voltages of 800 V [4]. Other materials systems such as poly-Si, Indium Gallium Zinc Oxide (IGZO) and Magnesium Zinc Oxide (MZO) have also been used in HVTFTs, reaching voltages of 240 V, 100 V, and 200 V, respectively [2]. We report a TIPS-pentacene solution-processed HVOTFT with an offset channel architecture that is capable of driving voltages up to |V DS| > 450 V, an improvement of three-fold compared to previous results [6]. An organosilane-based self-assembled
Downloaded from https://www.cambridge.org/core. Ac
Data Loading...
