• 한국진공학회:학술대회논문집
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• 한국진공학회 2007년도 제33회 하계학술대회 초록집
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• pp.360-360
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• 2007

• 한국광학회지
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• 제14권6호
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• pp.669-673
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• 2003

본 연구에서는 기존의 ridge waveguide laser diode(RWG LD)보다 ridge폭에 따른 측방향 단일모드 특성이 우수하고 planar 화에 유리하며 측방향의 유효 굴절률차를 ridge 구조에 추가로 성장된 InGaAsP층의 두께로 조절이 가능한 Buried RWG LD를제작하였다. 본 연구에서는 Buried RWG LD를 CBE장치로 InGaAs/InGaAsP multiple quantum well(MQW) 에피 웨이퍼를 성장하고, LPE로 재성장하여 B-RWG LD를 제작하였다. 또한 ridge 폭을 5 $\mu\textrm{m}$와 7 $\mu\textrm{m}$로 하여 B-RWG LD를 제작하고 특성을 비교하여 보았다. 제작된 7 $\mu\textrm{m}$ B-RWG LD에서 광출력이 20㎽에 이를 때까지 고차모드 발진에 의한 kink현상이 일어나지 않았으며, 포화 광출력이 80 ㎽ 이상임을 확인하였다. 제작된 B-RWG LD가 측방향 단일모드로 동작함을 확인하기 위해 FFP을 측정한 결과, ridge 폭이 5 $\mu\textrm{m}$일 때는 2.7I$_{th}$ , ridge 폭이 7 $\mu\textrm{m}$일 때는 2.4I$_{th}$ 까지 단일모드로 동작함을 확인할 수 있다.

• 한국전문물리치료학회지
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• 제10권2호
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• pp.61-70
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• 2003

The purposes of this study was to evaluate the effect of low power GaAsAl laser on tissue contraction in a linear incision wound on rat skin. The linear incision wound was made on the midline of the backside in the experimental animals. Low power laser applications with different intensities such as 3, 6, or 10 mW were applied to the experimental animals twice a day for 10 days. On either the seventh or tenth postoperative day, the quantitative analysis of the inflammatory reaction surrounding the linear incision wounds on the rats were performed using enzymatical analysis of myeloperoxidase (MPO) activity. The number of neutrophil was $.07-1.0{\times}106/m{\ell}$ from a normal blood sample that was obtained from the normal experimental animals. Each concentration of neutrophil showed .04-.62 unit activity of MPO. Therefore, the 6 unit activity of MPO per neutrophil was $.57{\pm}.014{\times}10^{-6}$ unit. On the 7th and 10th post operative day, non treated tissues demonstrated increased MPO activity as compared to that of normal tissue. These data indicated that the inflammatory reaction of tissue was induced after wound induction and the MPO activity were increased in the inflammed tissues. While both 3 mW or 6 mW intensity of laser treatments did not affect the tissue MPO activity, 10 mW intensity of laser treatment significantly decreased the tissue MPO activity on the 7th and 10th post operative day. These data demonstrated that only 10 mW intensity of laser treatment successfully suppressed tissue inflammatory reaction after wound induction. In conclusion, these findings suggested that 10 mW of GaAIAs laser treatments effectively suppressed the inflammatory reaction of tissue that was induced during the wound healing process.

• 한국광학회지
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• 제4권3호
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• pp.289-293
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• 1993

파장 792 nm의 AlGaAs 레이저 다이오드로 펌핑되는 Nd:YLF 레이저를 제작하여 펌핑세기와 펌핑빔의 파장에 대한 출력특성을 조사하였다. Brewster 각으로 되어있는 Nd:YLF봉에서 발생하는 비점수차를 보정하기 위하여 공진기 구조를 접힌형태로 하였다. 연속 출력 2.6Watt로 펌핑하였을 때 발진파장 1053 nm에서 최대 출력 1.1Watt를 얻었으며, 이때 전체효율이 39% 였다.

• Applied Microscopy
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• 제27권3호
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• pp.257-263
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• 1997

Microstructural characterizations of II-VI blue laser diodes which consist of quaternary $Zn_{1-x}Mg_xS_ySe_{l-y}$ cladding layer, ternary $ZnS_ySe_{l-y}$ guiding layer and $Zn_{0.8}Cd_{0.2}Se$ quantum well as active layer were carried out using the transmission electron microscope working at 300 kV. Even though the entire structure is pseudomorphic to GaAs substrate, the structure had contained numerous extended stacking faults and dislocations which had created at ZnSe/GaAs interfaces and then further grown to the top of the epilayers. These faults might be expected to cause the degradation and shortening the lifetime of laser devices.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2300-2302
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• 2005

Metal-Semiconductor-Metal type photodetector was fabricated with AlGaAs/InGaAs Quantum Well FET structures using simplified processing steps. The DC and RF responses were measured by 850nm wavelength injection laser. A DC responsivity in the quasisaturated regime was 0.45 A/W in CW measurements, and a bandwidth measured using a 850nm 40 ps pulsed laser was 16GHz. An electrical equivalent circuit model was extracted from measured S-parameter.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.118-119
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• 2013

High power, short wavelength red laser diodes (LDs) have attracted significant interests in a variety of fields due to their advantages in terms of reliability, compactness and cost. The higher brightness for human eyes is required, the shorter wavelength like 630 nm is necessary with higher output power. In this respect, LDs are promising as alternative candidates of gas or dye lasers for such applications due to their small size, high optical/electrical power conversion efficiency, robustness and so on. The crystalline quality of GaInP-AlGaInP multiple quantum wells (MQWs) and AlInP cladding layers is a crucial part in the device performance of GaInP red LDs. Here, we first investigated the effect of Si diffusion on the optical properties of GaInP-AlGaInP MQWs grown with different growth temperatures. Secondary ion mass spectroscopy (SIMS) measurements revealed that both the Mg and Si diffusion into MQW active region was significant. To reduce such diffusion, we employed undoped Mg and Si diffusion barrier and could improve the properties.Without both Mg and Si diffusion barriers, no lasing emission was observed. However, lasing emission was observed clearly for the red LDs with both Mg and Si diffusion barriers. We then investigated the temperature dependent optical properties of MQW layers grown with different well thicknesses (6, 8 and 10 nm). When the well thickness was 10 nm, the better crystalline quality was obtained. However, the observed LD performances were similar, probably due to the defects and impurities in the AlGaInP layer. Further investigation with the detailed analyses will be presented later.

• ETRI Journal
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• 제32권2호
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• pp.339-341
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• 2010

The fundamental transverse mode lasing of a hybrid laser diode is a prerequisite for efficient coupling to a single-mode silicon waveguide, which is necessary for a wavelength-division multiplexing silicon interconnection. We investigate the lasing mode profile for a hybrid laser diode consisting of silicon slab and InP/InGaAsP deep ridge waveguides. When the thickness of the top silicon is 220 nm, the fundamental transverse mode is lasing in spite of the wide waveguide width of $3.7{\mu}m$. The threshold current is 40 mA, and the maximum output power is 5 mW under CW current operation. In the case of a thick top silicon layer (1 ${\mu}m$), the higher modes are lasing. There is no significant difference in the thermal resistance of the two devices.

• ETRI Journal
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• 제26권5호
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• pp.475-480
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• 2004

Self-assembled InAs quantum dots (QDs) embedded in an InAlGaAs matrix were grown on an InP (001) using a solid-source molecular beam epitaxy and investigated using transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. TEM images indicated that the QD formation was strongly dependent on the growth behaviors of group III elements during the deposition of InAlGaAs barriers. We achieved a lasing operation of around 1.5 ${\mu}m$ at room temperature from uncoated QD lasers based on the InAlGaAs-InAlAs material system on the InP (001). The lasing wavelengths of the ridge-waveguide QD lasers were also dependent upon the cavity lengths due mainly to the gain required for the lasing operation.

• 한국광학회지
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• 제22권1호
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• pp.35-39
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• 2011

다층 비율 방정식을 이용한 1550 nm InGaAsP 레이저 다이오드의 PSPICE 등가회로 모델을 제안하고 구현하였다. 비율 방정식에 필요한 레이저 다이오드 파라미터들은 자기충족적 양자우물 해석법을 이용하여 도출하였다. 이 모델을 이용하여 실제 레이저 다이오드와 드라이버 IC를 포함하는 광송신기 회로 전체를 PSPICE로 구현하여 그 출력 값과 측정치를 비교하였다. 이 비교를 통하여 실제 레이저 다이오드의 패키징 시 발생하는 기생 커패시터 값을 산출하였다. 이를 바탕으로 한 PSPICE 출력 값은 여러 동작 주파수에서 실제 회로의 측정값과 일치함을 보였다.