• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08b
• /
• pp.1295-1297
• /
• 2007

In this study, we report that the characteristics of OTFTs can be improved by the UV exposure of the surface of the synthesized photo-reactive gate insulator, and be optimized by controlling the exposure time. As a gate dielectric, the modified PVP was prepared by substituting hydroxyl group in PVP with cinnamoyl group. The synthesis details and the effects of the modified PVP on the device performance are discussed.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.487-490
• /
• 2006

We propose a new method to achieve well-defined surface properties of the polymeric gate dielectrics without using SAM technique and inserting another organic/inorganic buffer layer. Pentacene thin film transistors(OTFTs) fabricated with the polyimide gate insulators with different side chain structures were demonstrated. Further, a relationship between the surface properties (surface morphology, surface energy, etc) of the films and the performance of OTFTs have investigated, which will be given in more detail in presentation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.04b
• /
• pp.43-44
• /
• 2009

We fabricated organic field-effect transistors (OFETs) based a fluorinated copper phthalocyanine ($F_{16}CuPc$) as an active layer. And we observed the surface morphology of the $F_{16}CuPc$ thin film. The $F_{16}CuPc$ thin film thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed the typical current-voltage (I-V) characteristics and capacitance-voltage (C-V) in $F_{16}CuPc$ FET and we calculated the effective mobility.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.504-505
• /
• 2008

We fabricated organic field-effect transistors (OFETs) based a fluorinated copper phthalocyanine ($F_{16}CuPc$) as an active layer. And we observed the surface morphology of the $F_{16}CuPc$ thin film. The $F_{16}CuPc$ thin film thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed the typical current-voltage (I-V) characteristics and capacitance-voltage (C-V) in $F_{16}CuPc$ FET and we calculated the effective mobility.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2009.10a
• /
• pp.566-567
• /
• 2009

We have examined the silicon nitride ($SiN_x$) as gate insulator with the ammonia ($NH_3$) plamsa treatment for the soluble derivatives of polythiophene as p-type channel materials of organic thin film transistors (OTFTs). Fabrications of the jetting-processed OTFTs with $SiN_x$ as gate insulator by $NH_3$ plasma treatment can be similar to performance of OTFTs with silicon dioxide ($SiO_2$) insulator.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08a
• /
• pp.267-270
• /
• 2007

Organic thin-film transistors (OTFTs) using organic semiconductors as an active layer are of interest for their use in low-cost, lightweight and flexible electronic products. Although the field-effect mobility of OTFTs is still lower than those of inorganic thin-film transistor, the advantages of easy manufacturing and processing make them suitable for selected applications. In this paper, we report the syntheses and characterization of new p-type OTFT materials.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.19 no.6
• /
• pp.563-567
• /
• 2006

Indium tin oxide (ITO) used as an electrode in organic light emitting diodes (OLEDs) and organic thin film transistors (OTFTs) was modified by a self-assembled monolayer (SAM). For device fabrication, surface of the ITO was modified by immersion in a solution including various phosphonic acid at room temperature in order to increase work function of an electrode. The work function of ITO with SAM was measured by Kelvin probe. Work function increase of 0.88 eV was observed in ITO with various SAM. Therefore, ohmic contact is achieved in an interface between ITO and organic semiconductors (pentacene). We analyzed the origin of work function increase of ITO with SAM by X-ray photoelectron spectroscopy. We confirmed that increase of oxygen bonding energy attributed to increase the work function of ITO. These results suggested that ITO with the SAM gives a high possibility for high performance of OLEDS and OTFTs.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
• /
• 2005.09a
• /
• pp.63-67
• /
• 2005

Pentacene channel OTFT(organic thin film transistor)을 SiOC 절연박막 위에서 film by thermal evaporation 방법을 이용하여 성장시켰다. CVD 방법으로 증착시킨 SiOC 절연막은 조성비에 따라 특성이 달라지므로 절연막 위에서의 펜타센의 화학적 반응을 조사하기 위해서 inorganic-type인 $O_2/(BTMSM\;+\;O_2)$ = 0.5의 비율을 갖는 SiOC 박막을 사용하였다. 팬타센 분자의 말단에서 SiOC 표면에서 Diels-Alder 반응에 의한 이중결합이 깨어지면서 안정된 성장을 하지만 온도가 높아감에 따라 표면에서의 $SN_2$(bimolecular nucleophilic substitution) 반응과 연쇄적인 화학반응에 의해 팬타센의 성장을 방해하는 것으로 나타났다.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.05a
• /
• pp.113.1-113.1
• /
• 2011

PEMS (printed electro-mechanical system) is fabricated by means of various printing technologies. Passive and active compo-nents in 2D or 3D such as conducting lines, resistors, capacitors, inductors and TFT(Thin Film Transistor), which are printed withfunctional materials, can be classified in this category. And the issue of PEMS is applied to a R2R process in the manu-facturing process. In many electro-devices, the vacuum process is used as the manufacturing process. However, the vacuum process has a problem, it is difficult to apply to a continuous process such as a R2R(roll to roll) printing process. In this paper, we propose an ESD (electro static deposition) printing process has been used to apply an organic solar cell of thin film forming. ESD is a method of liquid atomization by electrical forces, an electrostatic atomizer sprays micro-drops from the solution injected into the capillary with electrostatic force generated by electric potential of about several tens kV. ESD method is usable in the thin film coating process of organic materials and continuous process as a R2R manufacturing process. Therefore, we experiment the thin films forming of PEDOT:PSS layer and active layer which consist of the P3HT:PCBM. The organic solar cell based on a P3HT/PCBM active layer and a PEDOT:PSS electron blocking layer prepared from ESD method shows solar-to-electrical conversion efficiency of 1.42% at AM 1.5G 1sun light illumination, while 1.86% efficiency is observed when the ESD deposition of P3HT/PCBM is performed on a spin-coated PEDOT:PSS layer.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2002.08a
• /
• pp.754-758
• /
• 2002

In order to reach the high quality of organic thin films such as high mobility for device applications, it is strongly desirable to study the growth properties of pentacene film as a function of evaporation condition. Here, we report the structure and morphology of thermal evaporated pentacene thin film by AFM, SEM, and XRD as a function of the evaporation rate and substrate temperature. These results play a key role in determining the electric performance of organic thin film transistor devices.