• 분석과학
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• 제11권2호
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• pp.96-104
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• 1998

수 많은 광검출기들이 직선으로 집적된 광다이오드 어레이를 이용한 모세관 전기영동장치용 다채널 검출기를 개발하였다. 본 연구에서 사용된 광다이오드 어레이는 1024개의 광검출소자를 가지고 있으며 275~675 nm 파장범위에서 시료의 흡수분광스펙트럼을 검출할 수 있다. 이 장치는 30 ms내에 전 파장영역의 스펙트럼을 얻을 수 있으며, PC에 의하여 시료분석에 필요한 여러 가지 조건들을 제어할 수 있도록 설계하였다. 개발된 검출기의 성능을 L-ascorbic acid와 alizarin yellow GG를 사용하여 시험하였다. 본 연구에서 개발한 모세관 전기영동장치용 다채널 검출기의 재현성 실험결과 상대 표준편차는 5.6%이었다.

• 산업기술연구
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• 제37권1호
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• pp.27-31
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• 2017

In this paper, we have extended the research on the infrared sensor which has been limited to the plane. The reflection mechanism of the light on the curved surface is analyzed according to the curvature change and the emitted angle of photodiode and verified through experiments. The difference in the curvature causes a difference in the measurement distance, and also changes the intensity of the light coming into the phototransistor, thereby causing a difference in the output voltage. However, the difference in the output voltage due to the curvature change can be solved by adjusting the emitted angle of the photodiode to minimize the spot area formed on the curved surface regardless of the curvature. Therefore, it is possible to measure the distance by using the infrared sensor regardless of the curvature by aligning the photodiode to the center of the curved surface and adjusting the angle of the photodiode.

• 전자공학회논문지A
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• 제31A권6호
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• pp.88-97
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• 1994

We describe the design, fabrication, and performance of the optical fiber-photodiode 1$\times$12 arry module using mesa-type InS10.53T GaS10.47TAS/INP 1$\times$12 PIN photodiode array. We fabricated the PIN PD array for high-speed optical fiber parallel data link optimizing quantum efficiency, operating speed sensitivity from the PIN-FET structure, and electrical AC crosstalk. For each element of the array, the diameter of the photodetective area is 80 $\mu$m, the diameter of the p-metal pad is 90 $\mu$m, and the photodiode seperation is 250 $\mu$m to use Si v-groove. Ground conductor line is placed around diodes and p-metal pads are formed in zigzag to reduce Ac capacitance coupling between array elements. The dark current (IS1dT) is I nA and the capacitance(CS1pDT) is 0.9 pF at -5 V. No signifcant variations of IS1dT and CPD from element to element in the array were observed. We calulated the coupling efficiency for 10/125 SMF and 50/125 GI MMF, and measured the responsivity of the PD array at the wavelength is 1.55 $\mu$ m. Responsivities are 0.93 A/W for SMF and 0.96 A/W for MMF. The optical fiber-PD array module is useful in numerous high speed digital and analog photonic system applications.

• 센서학회지
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• 제22권4호
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• pp.256-261
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• 2013

This paper presents an extension of the dynamic range in a complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) using a stacked photodiode and feedback structure. The proposed APS is composed of two additional MOSFETs and stacked P+/N-well/P-sub photodiodes as compared with a conventional APS. Using the proposed technique, the sensor can improve the spectral response and dynamic range. The spectral response is improved using an additional stacked P+/N-well photodiode, and the dynamic range is increased using the feedback structure. Although the size of the pixel is slightly larger than that of a conventional three-transistor APS, control of the dynamic range is much easier than that of the conventional methods using the feedback structure. The simulation and measurement results for the proposed APS demonstrate a wide dynamic range feature. The maximum dynamic range of the proposed sensor is greater than 103 dB. The designed circuit is fabricated by the $0.35-{\mu}m$ 2-poly 4-metal standard CMOS process, and its characteristics are evaluated.

• 한국광학회지
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• 제16권4호
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• pp.345-353
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• 2005

포토 다이오드(photodiode) 조정 방식을 이용해서, 비전 시스템을 장착한 고가의 정밀 자동 조립조정 장비 없이 홀로그램 픽업 모듈을 제작하는 새로운 방법을 제안하였다. 저가격화를 위해서 리드 프레임형의 반도체 레이저와 COB(Chip on Board)형의 포토 다이오드를 사용했고, 초점 에러 신호(focus error, FES) 검출방법은 스팟 사이즈 검출법(spot size detection, SSD), 트랙 에러 신호(tracking error, TES) 검출방법은 삼빔법(3 beam method)을 이용했다. 이를 만족하는 픽업 홀로그램 모듈 광학계를 설계하고, 조립조정 프로세스 수립 및 시스템을 제작하였으며, 조립된 홀로그램 모듈을 이용하여 CD에서 데이터를 검출하는 실험을 통해 제안된 포토 다이오드 조정방식의 유용함을 입증하였다.

• Journal of information and communication convergence engineering
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• 제5권2호
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• pp.116-120
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• 2007

In this paper, the image sensor using the a-Si:H TFT is proposed. The optimum amorphous silicon thin film is deposited using plasma enhanced chemical vapor deposition (PECVD). TFT and photodiode both with the thin film are fabricated and form image sensor. The photodiode shows that $I_{dark}\;is\;{\sim}10^{-13}\;A,\;I_{photo}\;is\;{\sim}10^{-9}\;A\;and\;I_{photo}/I_{dark}\;is\;{\sim}10^4$, respectively. In the case of a-Si:H TFT, it indicates that $I_{on}/I_{off}\;is\;10^6$, the drain current is a few ${\mu}A\;and\;V_{th}\;is\;2{\sim}4$ volts. For the analysis on the fabricated image sensor, the reverse bias of -5 volts in ITO of photodiode and $70 {\mu}sec$ pulse in the gate of TFT are applied. The image sensor with good property was conformed through the measured photo/dark current.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1265-1267
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• 1995

In the fiber-photodiode(PD) coupling module using v-groove, the paraxial approximation is no longer valid because the beam enters obliquely the PD substrate with the angle of $20^{\circ}$ after being reflected from the $55^{\circ}$ mirror formed by anisotropically etching of the (100) silicon wafer. In this paper, we study the beam profile incident on the PD active area and fiber-PD coupling efficiency for this case.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
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• pp.754-756
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• 1999

In this paper, we have developed a high-sensitivity SNRD(Semiconductor Nuclear Radiation Detector) using silicon PIN photodiode. The SNRD is constructed with silicon PIN photodiode(S3590-05), preamplifier and shaping amplifier. To show the effectiveness of SNRD, nuclear radiation experiments are conducted with $\gamma$-ray Ba-133, Cs-137 and Co-60. The SNRD is different in characteristics of the energy spectrum to scintillation detectors. However, the SNRD have a good linearity on $\gamma$-ray energy and activity. The results of this paper can be applied to electronic personal dosimeter.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.281-284
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• 1995

A molecular photodiode was fabricated with hetero-Langmuir-Blodgett (LB) film consisting of an electron accepter(A) and sensitizer. N-Allyl-N-[3-propylamido-N\",N\"-야(n-octadecyl)]-4,4-bipyridum Dibromide and 7,8-dimethyl-10-dodecyl isoalloxan-zine were used as A and S units, respectively. By aligning hefter-LB film of A/S units on ITO glass with an aluminium thin film, a molecular photodiode with the structure of Metal/Insulator/Metal(MIM) was constructed. Due to excitation by irradiation with a 460nm monochromatic light source, the photo-induced unidirectional flow of electrons in the MIM device could be achieved and was detected as photocurrents. The direction of energy flow was in accordance with the energy level profile across the LB films. The photo switching function was achieved and the rectifying characteristics was obserbed in the molecular devise.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권1호
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• pp.35-41
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• 2017

We propose a novel multi-photodiode array (MPDA) based retinal implant IC with on/off stimulation strategy for a visual prosthesis with improved spatial resolution. An active pixel sensor combined with a comparator enables generation of biphasic current pulses when light intensity meets a threshold condition. The threshold is tuned by changing the discharging time of the active pixel sensor for various light intensity environments. A prototype of the 30-channel retinal implant IC was fabricated with a unit pixel area of $0.021mm^2$, and the stimulus level up to $354{\mu}A$ was measured with the threshold ranging from 400 lx to 13120 lx.