• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.2040-2042
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• 2012

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.518-520
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• 1997

Recently, thiophene oligomer with short chain lengths has received much attention as model compounds for facilitating better understanding of electronic and optical properties of polymers, because oligomer is well-defined chemical systems and its conjugation chain length can be exactly controlled. Moreover, organic this films based on conjugated thiophene oligomer have potential for application to electronic and optoelectronic devices such as MISFETs(metal-insulator-semiconductor field-effect transistors) and LEDs(light-emitting diodes). However, there is little knowledge on electronic and structural properties of linear-conjugated oligothiophenes in solid states, compared with those in solutions. $\alpha$-sexithienyl($\alpha$-6T) thin-films were deposited by OMBD(Organic Molecular Beam Deposition) technique, where the $\alpha$-6T was synthesized and purified by the sublimation method. The $\alpha$-6T films were deposited under various conditions. The effects of deposition rate, substrate temperature, and vacuum pressure on the formation of these films have been studied. The molecules in the $\alpha$-6T film deposited at a low deposition rate under a high vacuum were aligned almost perpendicular to the substrate. The $\alpha$-6T films deposited at an elevated substrate temperature showed higher conductivity than the film deposited at room temperature. Electrical characterization of these films will be also executed by using four-point probe measurement technique.

• 한국응용과학기술학회지
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• 제16권4호
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• pp.313-316
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• 1999

Organic semiconductors based on conjugated thiophene oligomer have great potential to be utilized as an active layer for electronic and optoelectronic devices. In this study, a conjugated oligomer such as ${\alpha}$-sexithiophene (${\alpha}$-6T) thin films was prepared by the Organic Molecular Beam Deposition (OMBD), and various electrode materials were also deposited by a simple vacuum evaporation, respectively. Those films were photolithographically patterned for the electrical measurements. Electrical charact-erization of the thin film transistor with various channel length were executed and the field effect mobility of these thin film transistors were also calculated by the formula using the experimental data.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.313-316
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• 1998

Conjugated oligomers have been already used as active layers in field effect transistors, photodiodes and electroluminescent devices. Particularly thiophene oligomers such $\alpha$ -sexithiophene($\alpha$-6T) attract great interest for its prospective app1ications in large-area flexible displays. In this study, we investigated the contact properties between the organic semiconductor $\alpha$-6T and metals such as Au(Gold), Ag(Silver), Cr(Chromium), Al(Aluminum), Cr(Chromium). Using the Transmission Line Model(TLM) method, specific contact resistances of the metal lines in contact with the $\alpha$-6T were determined. From the current-voltage characteristics, electrical conductivity of the $\alpha$-6T films is found.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.586-589
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• 1999

Organic semiconductors based on conjugated thiophene oligomer have great potential to be utilized as an active layer far electronic and optoelectronic devices. In this study, $\alpha$ -sexithiophene($\alpha$-6T) thin films and various electrode materials were deposited by Organic Molecular Beam Deposition(OMBD) and vacuum evaporation respectively. Those films were photolithographically patterned fur measurements. Electrical characterization of the thin film transistor with various channel length were measured, and field effect mobility is calculated by formula.

• Macromolecular Research
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• 제11권5호
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• pp.297-302
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• 2003

The imidization and cure reaction of a thermosetting phenylethynyl-terminated amic acid (LaRC PETI-5) in film form have been monitored as a function of temperature by means of a steady-state fluorescence technique using a front-face illumination method. The variation of the fluorescence emission spectra of LaRC PETI-5 can be divided into four temperature regions; Region I: below 15$0^{\circ}C$, Region II: 150-25$0^{\circ}C$, Region III: 250-35$0^{\circ}C$, and Region IV: above 35$0^{\circ}C$. The fluorescence spectra in Region I are largely influenced by residual N-methyl-2pyrrolidinone in the polymer and also slightly by partial imidization of the polymer. There is a combined effect of imidization and solvent removal on the fluorescence behavior in Region II. The spectra in Regions III and IV are due significantly to the cure reaction of LaRC PETI-5 and to a post-cure effect of the polyimide, respectively. This spectroscopic evidence indicating the transformation of the amic acid imide oligomer into the corresponding polyimide via imidization and cure, agrees well with thermal analysis results obtained previously. The intermediate stage of cure in the range of 250-30$0^{\circ}C$ predominantly influences the change of the fluorescence intensity. The later stage above 30$0^{\circ}C$ significantly influences the position of the spectrum. This fluorescence study also supports the mechanism proposed in earlier work that the crosslinking reaction takes place at the reaction sites in the conjugated polyene and the phenylethynyl end group in the polyimide chain.

• 공업화학
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• 제22권5호
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• pp.545-550
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• 2011

바이오 분자의 고정 링커로 전기전도도가 높은 방향족 공액구조의 4-(2-(4-(acetylthio)phenyl)ethynyl)benzoic acid (APBA) 분자를 합성한 후, APBA 자기조립 단분자막을 제작하였다. 제작한 APBA 자기조립 단분자막의 구조를 분석하였고, 페로센으로 고정화시킨 APBA의 자기조립 단분자막의 전기화학적 특성을 조사하였다. 부탄티올 단분자막에 APBA를 삽입시켜 혼합 단분자막을 제조하여 XPS로 금 기판에 대한 혼합 단분자막의 수직 배향성을 조사하였다. 또한, APBA 혼합 시간에 따른 APBA와 부탄티올(BT) 혼합 단분자막에 페로센을 고정화하여 전기화학적 산화 환원 특성을 조사하였다. 혼합 단분자막의 전기화학적 활성은 혼합 시간의 증가에 따라 증가하였고, 부탄티올 단분자막 기판을 APBA 용액에 36 h 침지시켰을 때 가장 높은 페로센 분자의 산화 환원 전류값을 얻었다.

• Applied Microscopy
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• 제30권4호
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• pp.403-412
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• 2000

1. 아메바 항-액틴의 Ag-Ab 반응과 이를 항-생쥐 IgG-금 입자로 표지한 결과는 주로 정세 포 및 정자의 핵질에 특이적으로 표지되었고 첨체에서는 그 반응을 볼 수 없었다. 2. 표지된 항-액탠 금 입자로 볼 때 정자 핵질의 G-액틴 또는 G-actin oligomer는 정세포의 F-액틴에서 유래되는 것으로 사료된다. 3. 첨체의 액틴은 주로 F-액틴으로 첨체돌기 형성에 참여하지 않는 위상인 것으로 관찰된다. 4. 미세구조의 변화, 정세포 체적의 감소, 정세포 및 정자 핵에 표지되는 금 입자의 증가와 이들 현상이 나타나는 동시성으로 볼 때 정세포 핵의 형태변화의 내용은 응축이고 이는 F-actin의 탈중합 반응에 의한 G-액틴의 생성이 원인일 것으로 사료된다.