Vacuum-and-solvent-free fabrication of organic semiconductor layers for field-effect transistors

Matsushima, Toshinori; Sandanayaka, Atula S. D.; Esaki, Yu; Adachi, Chihaya

doi:10.1038/srep14547

Cited by 19 publications

(19 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…37,38 C8-BTBT has a melting point of 130°C and therefore melts in the fusing roller of an office laser printer without needing any modifications in its construction. 39 By covering the device with a powder of C8-BTBT we then fused the C8-BTBT to the device in a bottom-gate, bottom-contact orientation by sending the paper through the laser printer fusing roller, which resulted in melting of the semiconductor layer, followed by recrystallization after exiting the paper feed of the printer. This deposition is in fact a simplified version of the laser-printing technique for OSC devices that we developed recently, and was adopted here with no further optimization.…”

Section: Contact Deposition and Patteringmentioning

confidence: 99%

Contact patterning by laser printing for flexible electronics on paper

2019

View full text Add to dashboard Cite

The desire for cost-effective strategies for producing organic electronic devices has led to many new methods for the organic semiconductor layer deposition; however, manufacturing contacts remains an expensive technique due to the high cost of both the materials used and the processing necessary for their patterning. In this work, we present a method for contact deposition and patterning, which overcomes these limitations and allows fabrication of all-printed organic thin-film transistors on paper. The method relies on depositing contacts using aerosol spray and patterning them with a digitally printed mask from an office laser printer, at ambient temperature and pressure. This technique, which we have denoted aerosol spray laser lithography, is costeffective and extremely versatile in terms of material choice and electrode geometry. As the processing temperature does not exceed 155°C, it is compatible with a variety of substrates, including plastic or paper. The success of this method marks an opportunity for a rapid, scalable, and low-cost alternative to current electrode-manufacturing techniques for development of flexible, large-area, electronic applications.

show abstract

Section: Contact Deposition and Patteringmentioning

confidence: 99%

Contact patterning by laser printing for flexible electronics on paper

2019

View full text Add to dashboard Cite

show abstract

“…To fabricate an active semiconducting layer, vacuum vapor deposition and solution‐processing methods are competitively employed. However, recent research is concerned more with solution processability as a platform to afford simplified fabrication . Spin coating, dip casting, and ink‐jet printing are examples of solution‐processing methods .…”

Section: Introductionmentioning

confidence: 99%

Solution‐Processable Unsymmetrical Triarylamines: Towards High Mobility and ON/OFF Ratio in Bottom‐Gated OFETs

Dheepika

Imran

Bhuvanesh

et al. 2019

Chemistry A European J

View full text Add to dashboard Cite

Self‐assembly of organic small molecules into an ordered thin film has been the key strategy towards efficient charge transport for organic field‐effect transistors (OFETs). Solution processing is a feasible and economic way to enhance pi–pi interaction. Herein, nitrile‐substituted unsymmetrical triarylamines for OFET applications with high mobility are reported. The compounds were constructed by Suzuki cross‐coupling reactions under inert conditions. The HOMO level of about 5.3 eV indicates good hole‐transporting ability. OFETs were assembled in bottom‐gate, top‐contact architecture. Devices fabricated from a binary solvent system exhibited excellent p‐channel characteristics, with impressively high charge‐carrier mobility of up to 2.58 cm2 V−1 s−1 and ION/OFF current ratios of 106–107. SEM and AFM analysis showed the efficient molecular self‐assembly attained by the simple and effective solvent‐engineering method. Theoretical insights obtained by DFT calculations supported by single‐crystal structures showed that the crystalline nature and packing modes of these compounds ensure high mobility. The results prove that these compounds have great potential for use in numerous electronic applications, such as sensors and logic switches.

show abstract

“…The thickness decrease and improved mechanical and electrical characteristics of the film by CIP were attributed to the gap compression inside the H 2 Pc film. Additionally, we recently demonstrated incorporation of a very high concentration of oxygen, on the order of 4.4 × 10 20 cm −3 , into organic films using a modified CIP technique; OFETs containing organic powder compressed with HIP exhibiting a maximum hole mobility of 0.22 cm 2 V −1 s −1 ; and an increase of the efficiency of organic–inorganic perovskite solar cells by about 1.5 times through improvement of perovskite morphology and crystallinity by HIP . Here, one question arises: What kinds of organic films can be compressed by the CIP and HIP techniques?…”

Section: Introductionmentioning

confidence: 99%

Current Enhancement in Organic Films through Gap Compression by Cold and Hot Isostatic Pressing

Esaki

Matsushima

Adachi

2016

Adv Funct Materials

Self Cite

View full text Add to dashboard Cite

wileyonlinelibrary.com(OSCs) and organic fi eld-effect transistors (OFETs) and have rather rough surfaces with grain structures, possess relatively large macroscopic gaps between grains and other grains, substrates, or electrodes. [ 3,4 ] Densities of vacuum-deposited and solution-processed organic fi lms are generally lower than those of single crystals. [ 5 ] The typical difference in density between organic fi lms and single crystals is several to over ten percent, which corresponds to the total volume of gaps in an organic fi lm. Such gaps in amorphous and polycrystalline fi lms might be expected to impede carrier injection and transport because of ineffi cient carrier movement through indirect routes to avoid the gaps. For example, carrier movement across gaps between grains is a limiting step because they might be potential barriers or carrier traps. [ 6,7 ] The removal of gaps between grains enhanced carrier mobilities in OFETs containing polycrystalline organic fi lms. [ 8,9 ] Densities of amorphous organic fi lms depend on substrate temperature during vacuum deposition, with density variation of around 1%. For example, fi lms of stable organic glasses with high densities form at T substrate / T g = 0.8−0.9, where T substrate is the substrate temperature during vacuum deposition and T g is the glass transition temperature of an organic material. [ 10 ] Lower water uptake was realized in denser organic fi lms vacuum deposited at a suitable substrate temperature. [ 11 ] Low water uptake should improve the long-term air stability of organic devices because water promotes the degradation of organic materials, especially in the presence of photo generated excited states and redox-generated radicals, cations, and anions. [ 12,13 ] We expect that the electrical characteristics and air stability of organic devices, such as OLEDs, OSCs, and OFETs, will be enhanced if the macroscopic and microscopic gaps in the organic fi lms are removed.Our strategy to remove the gaps from organic fi lms is very simple: the gaps are irreversibly compressed by applying high pressure to polycrystalline and amorphous organic fi lms. To compress the fi lms, we focused our attention on cold isostatic pressing (CIP) and hot isostatic pressing (HIP). CIP and HIP have been widely used to compress and mold metal, ceramic, plastic, and composite powders into certain forms. [14][15][16] In this approach, the powder is enclosed in a fl exible, sealed rubber bag and immersed in a pressurization vessel fi lled with a liquid. Standard metal mold pressing (MMP) applies uniaxial The spatial gaps in organic fi lms are compressed using cold and hot isostatic pressing (CIP and HIP, respectively) with the aim of enhancing their electrical characteristics. The microscopic gaps formed in amorphous organic fi lms by ineffi cient molecular packing are diffi cult to compress using CIP and HIP; however, the macroscopic gaps formed between grains and other grains or substrates in polycrystalline organic fi lms can be compressed using CIP and HIP. The gap com...

show abstract

Vacuum-and-solvent-free fabrication of organic semiconductor layers for field-effect transistors

Cited by 19 publications

References 38 publications

Contact patterning by laser printing for flexible electronics on paper

Contact patterning by laser printing for flexible electronics on paper

Solution‐Processable Unsymmetrical Triarylamines: Towards High Mobility and ON/OFF Ratio in Bottom‐Gated OFETs

Current Enhancement in Organic Films through Gap Compression by Cold and Hot Isostatic Pressing

Contact Info

Product

Resources

About