• 한국자기학회:학술대회 개요집
• /
• 한국자기학회 2002년도 춘계연구발표회 논문개요집
• /
• pp.22-23
• /
• 2002

• 한국자기학회:학술대회 개요집
• /
• 한국자기학회 2012년도 자성 및 자성재료 국제학술대회
• /
• pp.65-66
• /
• 2012

• 한국전기전자재료학회논문지
• /
• 제18권11호
• /
• pp.1056-1060
• /
• 2005

We investigated the fabrication and characteristics of the nitride-based spin-polarized LEDs with room-temperature ferromagnetic (Ga,Mn)N layer as a spin injection source. The (Ga,Mn)N thin films having room-temperature ferromagnetic ordering were found to exhibit the negative MR and anomalous Hall resistance up to room temperature, revealing the existence of spin-polarized electrons in (Ga,Mn)N films at room temperature. The electrical characteristics in the spin LEDs did not degraded in spite of the insertion of the (Ga,Mn)N layer into the LED structure. In EL spectra of the spin LEDs, it is confirmed that the devices produce intense EL emission at 7 K as well as room temperature. These results are expected to open up new opportunities to realize room-temperature operating semiconductor spintronic devices.

• 한국자기학회:학술대회 개요집
• /
• 한국자기학회 2017년도 임시총회 및 하계학술연구발표회
• /
• pp.182-182
• /
• 2017

• 한국재료학회지
• /
• 제26권2호
• /
• pp.84-89
• /
• 2016

We present the rectifying and nitrogen monoxide (NO) gas sensing properties of an oxide semiconductor heterostructure composed of n-type zinc oxide (ZnO) and p-type copper oxide thin layers. A CuO thin layer was first formed on an indium-tin-oxide-coated glass substrate by sol-gel spin coating method using copper acetate monohydrate and diethanolamine as precursors; then, to form a p-n oxide heterostructure, a ZnO thin layer was spin-coated on the CuO layer using copper zinc dihydrate and diethanolamine. The crystalline structures and microstructures of the heterojunction materials were examined using X-ray diffraction and scanning electron microscopy. The observed current-voltage characteristics of the p-n oxide heterostructure showed a non-linear diode-like rectifying behavior at various temperatures ranging from room temperature to $200^{\circ}C$. When the spin-coated ZnO/CuO heterojunction was exposed to the acceptor gas NO in dry air, a significant increase in the forward diode current of the p-n junction was observed. It was found that the NO gas response of the ZnO/CuO heterostructure exhibited a maximum value at an operating temperature as low as $100^{\circ}C$ and increased gradually with increasing of the NO gas concentration up to 30 ppm. The experimental results indicate that the spin-coated ZnO/CuO heterojunction structure has significant potential applications for gas sensors and other oxide electronics.

• 마이크로전자및패키징학회지
• /
• 제10권4호
• /
• pp.35-38
• /
• 2003

ITO/glass 기판 위에 발광물질로서 poly(2-methoxy-5-(2-ethylhexoxy)-1,4-phenylenevinylene (MEH-PPV)를 이용하여 스핀코팅법(spin coating)으로 Glass/ITOM/MEH-PPV/Al 구조를 가지는 고분자 유기 발광 다이오드를 제작하였다. MEH-PPV 박막형성시 열처리온도에 따른 다이오드의 전기적, 광학적 특성을 조사하였다. 열처리 온도를 $65^{\circ}C$에서 $170^{\circ}C$로 증가함에 따라 유기 발광다이오드의 발광휘도는 10V 인가전압에서 630 cd/$\m^2$에서 280 cd/$\m^2$로 크게 감소하였다. 또한 $65^{\circ}C$에서 열처리한 시료의 경우 약 2 lm/W의 최대 발광효율을 나타내었다. 이러한 결과는 높은 온도에서 열처리시 MEH-PPV 유기 형광층과 전극간의 상호반응에 의한 계면 거칠기의 증가와 새로운 절연층의 형성 등과 관련이 있는것으로 판단된다.

• 한국자기학회:학술대회 개요집
• /
• 한국자기학회 2002년도 동계연구발표회 논문개요집
• /
• pp.156-157
• /
• 2002

자성체, 반도체의 계면을 조절하여 스핀 산란을 없애는 방법으로 A12O3를 이용하여, 스핀의 정보를 잃지 않고 반도체에 주입할 수 있는 방법을 연구하였다. 반도체에 월형 편광된 laser를 조사하여 내부에서 여기한 전자 spin이 자성체 내부로 흘러가면서 일어나는 현상을 관측한 것이다[1], [2]. 일반적인 반도체와 금속간의 접합을 구성한 schottky-barrier 특성이 아닌 접합 사이에 인위적으로 barrier를 형성하여 그 특성을 관측하였다. n-type 과 p-type의 시료를 제작하여 I-V 특성을 온도에 따라 I-V 특성 측정하였다. (중략)

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2007년도 추계학술대회논문집
• /
• pp.77-81
• /
• 2007

Pentacene was dissolved in N-methyspyrrolidone (NMP) and mixed with poly(3,4-ethylenedioxythiophene), poly(styrenesulfonate) (PEDOT:PSS). The solution color changed from deep purple to intense yellow. As the dissolution time increased, visible absorption decreased and ultraviolet (UV) absorption increased. PEDOT:PSS or Pentacene-PEDOT:PSS was spin-coated to control the layer thickness. Three-layered Schottky diodes consisting of Al, PEDOT:PSS or PEDOT:PSS-pentacene, and Au with thickness of 300nm, respectively, were fabricated. The current densities of $4.8{\mu}A/cm^2$ at 2.5MV/m and $660{\mu}A/cm^2$ at 1.9MV/m were obtained for the Au/PEDOT:PSS/Al and Au/Pentacene-PEDOT:PSS/Al Schottky diodes, respectively. The current density of the Schottky diode was enhanced by about two orders of magnitude by doping pentacene to PEDOT:PSS.

• 한국전기전자재료학회논문지
• /
• 제18권7호
• /
• pp.641-646
• /
• 2005

To fabricate a single layer white organic light emitting diode (OLED), a novel non-conjugated blue emitting material PPPMA-co-DTPM copolymer was synthesized containing a perylene moiety unit with hole transporting and blue emitting ability and a triazine moiety unit with electron transporting ability. The devices were fabricated using PPPMA-co-DTPM $(PPPMA[70\;wt\%]:DTPM[30\;wt\%])$ copolymer by varying the doping concentrations of each red, green and blue fluorescent dye, by molecular-dispersing into Toluene solvent with spin coating method. In case of ITO/PPPMA-co-DTPM:TPB$(3\;mol\%):C6(0.04\;mol\%):NR(0.015\;mol\%)/Al$ structure, as they were molecular-dispersing into 30 mg/ml Toluene solvent, nearly-pure white light was obtained both (0.325, 0.339) in the CIE coordinates at 18 V and (0.335, 0.345) at 15 V. The turn-on voltage was 3 V, the light-emitting turn-on voltage was 4 V, and the maximum external quantum efficiency was $0.667\%$ at 24.5 V. Also, in case of using 40 mg/ml Toluene solvent, the CIE coordinate was (0.345, 0.342) at 20 V.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2011년도 제40회 동계학술대회 초록집
• /
• pp.146-146
• /
• 2011

The blue light emitting diode (LED) structure based on non-polar a-plane (11-20) GaN which was coated TiO2 nanoparticles using spin coating method was grown on r-plane (1-102) sapphire substrates to improve light extraction efficiency. We report on the emission and structural properties with temperature dependence of photoluminescence (PL) and x-ray rocking curves (XRC). From PL results at 13 K of undoped GaN samples, basal plane stacking fault (BSF) and near band edge (NBE) emission peak were observed at 3.434 eV and 3.484 eV, respectively. We also found the temperature-induced band-gap shrinkage, which was fitted well with empirical Varshini's equation. The PL intensity of TiO2 nanoparticles ?coated multiple quantum well (MQW) sample is decayed slower than that of no coating sample with increasing temperature. The anisotrophic strain and azimuth angle dependence in the films were shown from XRC results. The full width at half maximum (FWHM) along the GaN [11-20] and [1-100] directions were 564.9 arcsec and 490.8 arcsec, respectively. A small deviation of FWHM values at in-plane direction is attributed to uniform in-plane strain.