http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
주방 GCD 70 구상흑연 주철의 기계적 성질 및 흑연형상에 미치는 주물 두께의 영향
김창주,윤한상 대한금속재료학회(대한금속학회) 1984 대한금속·재료학회지 Vol.22 No.6
Casting thickness influences mechanical property and graphite shape in ductile cast iron and the results from this study are as follows: 1) The strength and the hardness were decreased rectilinearly as the casting size increased from Ø25㎜ to Ø100㎜ and were nearly same at the size of Ø100㎜ and 150㎜. 2) The strength and the hardness were appeared homogeneous in every step bar of the same thickness. 3) The best ductility was obtained at Ø50㎜. 4) The maximum diameter of huge graphite nodule was 130㎛.
Optical Investigation of GaInP-AlGaInP Quantum-well Layers for High-power Red Laser Diodes
김창주,최재혁,송근만,신찬수,고철기,김호경 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.9
We investigated the effect of Si diffusion on the optical properties of GaInP-AlGaInP multiple quantum wells (MQWs) grown at different growth temperatures. Photoluminescence (PL) measurements showed that the emission wavelength was shortened and the PL intensity decreased with increasing growth temperature. Secondary-ion mass spectroscopy (SIMS) measurements showed that the Si concentrations in the MQW active region were similar regardless of the growth temperature. Different growth temperatures of the MQW layers might give rise to different compositions in the MQW layers, resulting in different emission wavelengths. We also investigated the temperaturedependent optical properties of MQW layers grown with different well thicknesses (6, 8, and 10 nm). For the sample with a well thickness of 10 nm, better crystalline quality, better GaInP-AlGaInP interfaces and higher activation energy were observed compared to other samples. However, the activation energies for all three samples were found to be smaller than the carrier confinement energy. The carrier loss in the GaInP-AlGaInP QW might be related to defects and impurities in the AlGaInP layer.
김창주,최재혁,배성주,Keun-Man Song,신찬수,고철기,김호경 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.61 No.7
We investigated the doping profiles of Mg and Si dopants near the multiple quantum well (MQW) active region in 640 nm band GaInP-AlGaInP red laser diodes (LDs). With a 200 nm thick Mg diffusion barrier, the optimal doping profiles with an Mg flow rate of 80 sccm were obtained. Without Si diffusion barrier, significant Si diffusion into MQW layers was observed even at the lowest Si flow rate of 25 sccm. A 100 nm thick Si diffusion barrier suppressed effectively the Si diffusion into MQW layers, resulting in the improved laser performance. The results suggest that undoped diffusion barriers for Mg and Si dopants in AlInP cladding layers with optimal thickness will enhance the laser performance.