• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.170-170
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• 2006

[ ${\pi}-conjugated$ ] organic and polymeric semiconductors are receiving considerable attention because of their suitability as an active layer for electronic devices. An organic inverter with a full swing and a high gain can be obtained through the good qualities of the transfer characteristics of organic thin-film transistors (OTFTs); for example, a low leakage current, a threshold voltage ($V_{th}$) close to 0 V, and a low sub-threshold swing. One of the most critical problems with traditional organic inverters is the high operating voltage, which is often greater than 20 V. The high operating voltage may result in not only high power consumption but also device instabilities such as hysteresis and a shift of $V_{th}$ during operation. In this paper, low-voltage and little-hysteresis pentacene OTFTs and inverters in conjunction with PEALD $Al_{2}O_{3}\;and\;ZrO_{2}$ as the gate dielectrics are demonstrated and the relationships between the transfer characteristics of OTFT and the voltage transfer characteristics (VTCs) of inverter are investigated.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.194-197
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• 2006

One novel electrode-architecture has been adapted to fabricate transparent OTFTs. The device has more than 70% transmittance, yet reminds high performance. Furthermore, we also use transfer line method to prove that the device performance enhancement indeed contributes from the reduction of the contact resistances. It is anticipated that the transparent OTFTs would be very suitable to be the driving circuits for liquid crystal displays (LCDs).

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.314-316
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• 2006

In this paper, the plastic organic thin-film transistors (OTFTs) with $32{\ast}32$ array are presented. Flexible organic light emitting diodes (OLEDs) operated by OTFTs are fabricated with a novel lamination method and the results are also presented. OTFT pixels defined by photolithography, and pentacene deposited by thermal evaporation. Fabrication method and the performances of green PHOLEDs with high efficiency, stability, and electrical performance are discussed.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.975-978
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• 2008

Novel sulfur-containing aromatic compounds were developed as stable, high-performance organic semiconductors for OTFT applications. Of them, dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT) consisting of six aromatic rings gave high quality thin films by vapor deposition, which acted as a superior FET channel showing FET mobility as high as $3.0\;cm^2V^{-1}s^{-1}$. On the other hand, highly soluble 2,7-dialkyl[1]benzothieno[3,2-b][1]benzothiophenes ($C_n$-BTBTs) gave solution-processible OTFTs with FET mobility higher than $1.0\;cm^2V^{-1}s^{-1}$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.470-470
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• 2012

Organic thin film transistors (OTFTs) backplane constitute the active elements in new generations of plastic electronic devices for flexible display. The overall OTFTs performance is largely depended on the properties and quality of each layers of device material. In solution based process of organic semiconductors (OSCs), the interface state is most impediments to preferable performance. Generally, a threshold voltage (Vth) shift is usually exhibited when organic gate insulators (OGIs) are exposed in an ambient air condition. This phenomenon was caused by the absorbed polar components (i.e. oxygen and moisture) on the interface between OGIs and Soluble OSCs during the jetting process. For eliminating the polar component at the interface of OGI, the role of high vacuum seasoning on an OGI for all solution processable OTFTs were studied. Poly 4-vinly phenols (PVPs) were the material chosen as the organic gate dielectric, with a weakness in ambient air. The high vacuum seasoning of PVP's surface showed improved performance from non-seasoning TFT; a $V_{th}$, a ${\mu}_{fe}$ and a interface charge trap density from -8V, $0.018cm^2V^{-1}s^{-1}$, $1.12{\times}10^{-12}(cm^2eV)^{-1}$ to -4.02 V, $0.021cm^2V^{-1}s^{-1}$, $6.62{\times}10^{-11}(cm^2eV)^{-1}$. These results of OTFT device show that polar components were well eliminated by the high vacuum seasoning processes.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1364-1369
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• 2005

In this paper, we have identified the mechanism of C-V hysteresis behavior often observed in pentacene organic thin-film transistors (OTFTs). The capacitance-voltage (C-V) characteristics were measured for pentacene OTFTs fabricated on glass substrates with MoW as gate/source/drain electrode and TEOS $SiO_2$ as gate insulator. The measurements were made at room temperature and elevated temperatures. From the room temperature measurements, we found that the hysteresis behavior was caused by hole injection into the gate insulator from the pentacene semiconductor for large negative gate voltages, resulting in the negative flat-band voltage shift. However electron injection was observed only at elevated temperatures

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.151-154
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• 2007

We demonstrate a novel selective patterning process of a semiconducting polymer for channel regions to fabricate an array of organic thin-film transistors (OTFTs). This process is applicable for various organic films over large area. A reflective liquid crystal display based on the OTFT array was produced using the selective patterning through a wettability control.

• 대한전자공학회논문지SD
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• 제47권8호
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• pp.7-12
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• 2010

본 논문에서는 BPhen(Bathophenanthroline)과 BPhen에 Cs가 도핑 된 interlayer를 $C_{60}$활성층과 Al전극사이에 주입해 $C_{60}$을 기반으로 한 유기박막트랜지스터 (OTFTs)를 제작하여 전기적 특성을 향상시켰다. BPhen층을 증착하면 유기물과 금속층계면의 표면 거칠기가 낮아져 결과적으로 성능이 향상되는 것을 알 수 있었다. 또한 BPhen에 Cs가 도핑 된 interlayer를 co-evaporation을 이용하여 주입하였을 경우는 Contact resistance가 감소하였다. 이러한 $C_{60}$을 기반으로 한 BPhen에 Cs가 도핑 된 interlayer를 삽입한 유기박막트랜지스터는 향후 n형 유기박막트랜지스터를 제작하는데 있어서 적용이 될 것이라고 기대된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.86-89
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• 2004

Organic thin film transistors (OTFTs) are fabricated on the plastic substrate through 4-level mask process without photolithographic patterning to yield the simple fabrication process. And we herewith report for the effect of dielectric surface modification on the electrical characteristics of OTFTs. The KIST-JM-1 as an organic molecule for the surface modification is deposited onto the surface of zirconium oxide $(ZrO_2)$ gate dielectric layer. In this work, we have examined the dependence of electrical performance on the interface surface state of gate dielectric/pentacene, which may be modified by chemical properties in the gate dielectric surface.

• 한국전기전자재료학회논문지
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• 제16권11호
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• pp.961-968
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• 2003

In order to reach the high electrical quality of organic thin film transistors (OTFTs) such as high mobility and on-off current ratio, it is strongly desirable to study the enhancement of electrical properties in OTFTs. Here, we report the novel method of hydrogen plasma treatment to improve electrical properties in inverted staggered OTFTs based on pentacene as active layer. To certify the effect of this method, we compared the electrical properties of normal device as a reference with those of device using the novel method. In result, the normal device as a reference making no use of this method exhibited a field effect mobility of 0.055 $\textrm{cm}^2$/Vs, on/off current ratio of 10$^3$, threshold voltage of -4.5 V, and subthreshold slope of 7.6 V/dec. While the device using the novel method exhibited a field effect mobility of 0.174 $\textrm{cm}^2$/Vs, on/off current ratio of 10$\^$6/, threshold voltage of -0.5 V, and subthreshold slope of 1.49 V/dec. According to these results, we have found the electrical performances in inverted staggered pentacene TFT owing to this method are remarkably enhanced. So, this method plays a key role in highly improving the electric performance of OTFTs. Moreover, this method is the first time yet reported for any OTFTs.