• Title/Summary/Keyword: Photodiode

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Design and Fabrication Technologies of Avalanche Photodiode for Optical Communication (애벌란치형 광검출기 설계 및 제작 기술)

  • 박찬용;강승구;신명훈;주흥로
    • Proceedings of the Optical Society of Korea Conference
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    • 2001.02a
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    • pp.164-165
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    • 2001
  • 애벌란치형 광검출기(Avalanche Photodiode; APD)는 내부 이득을 갖고 있어 수신감도가 좋고 고속 동작이 가능하여 광통신에 있어서 매우 중요한 소자이다. 초기에는 공정의 용이성 등으로 인해 Ge을 소재로 하는 APD가 많이 사용되었으나 1.55 $\mu\textrm{m}$ 파장에서 광흡수 특성이 좋지 않고 전자와 정공의 이온화 계수비가 거의 같아 GB Product이 낮으므로 점차 이들 특성이 우수한 InP/InGaAs APD가 사용되었다. InGaAs는 밴드갭은 Ge보다 크지만 직접천이형 밴드구조를 갖기 때문에 1.67 $\mu\textrm{m}$까지 광흡수 특성이 좋고 소수캐리어의 이동도가 높아 고속동작에 유리하다. (중략)

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Voltage-Dependent Residual Phase Noise of a Photodiode Measurement Based on a Two-Tone Correlation Method

  • Zhu, Dezhao;Yang, Chun;Cao, Zhewei;Li, Xianghua
    • Journal of the Optical Society of Korea
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    • v.18 no.5
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    • pp.594-597
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    • 2014
  • We propose a novel approach to measure the residual phase noise (RPN) of a photodiode (PD) based on a two-tone correlation method. Compared with the previous measurements of the RPNs of PDs, this method is more convenient in practical application. In this method, two microwave sources and other components were placed in two isolated links sharing the same PD, so the noises of them were uncorrelated. With an FFT analyzer, the uncorrelated noises could be mostly suppressed while only the RPN of the PD was preserved. Voltage-dependent nonlinearities of PDs were studied previously. In this letter, we investigate the relationship between the RPN of the PD and the bias voltage on the PD. By changing the bias voltage, the difference of the RPN can be up to 10 dB.

A Study on Implemention of Pulse Oximeter System (펄스옥시미터 개발에 관한 연구)

  • Park, Y.S.;Kim, K.E.;Lim, H.S.;Yang, D.G.;Huh, W.
    • Proceedings of the KOSOMBE Conference
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    • v.1993 no.05
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    • pp.116-119
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    • 1993
  • In this paper, we implemented a pulse wave type oximeter system that continuously measure the of oxyhemoglobin saturation of the arterial blood(SaO2) and pulse rate with non-invasively. We use the transmission type and reflection type transducer for comparison the percentage of hemoglobin oxgen saturation. The light Iron the two kind of LEDs is transmitted through the tissue, then received by a single photodiode with alternatively. By the phase sensitive detection circuit, the output of the photodiode is separated in to red and near infrared signal. We calculated a ratio of light transmittance between two kind of LEDs, and then, it is applied to the oxgen saturation coefficent calculation formular.

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Improved Circuits for Single-photon Avalanche Photodiode Detectors

  • Kim, Kyunghoon;Lee, Junan;Song, Bongsub;Burm, Jinwook
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.6
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    • pp.789-796
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    • 2014
  • A CMOS photo detection bias quenching circuit is developed to be used with single photon avalanche photodiodes (SPADs) operating in Geiger mode for the detection of weak optical signals. The proposed bias quenching circuits for the performance improvement reduce the circuit size as well as improve the performance of the quenching operation. They are fabricated in a $0.18-{\mu}m$ standard CMOS technology to verify the effectiveness of this technique with the chip area of only $300{\mu}m^2$, which is about 60 % of the previous reported circuit. Two types of proposed circuits with resistive and capacitive load demonstrated improved performance of reduced quenching time. With a commercial APD by HAMAMATSU, the dead time can be adjusted as small as 50 ns.

Automatic Alignment of a Differential Detector to the Optical Signal in a Wireless Optical Interconnection (무선광연결에서 신호광에 자동 정렬하는 차동검출기)

  • 이성호
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.5
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    • pp.822-829
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    • 2000
  • In this paper, we introduce a differential detector that automatically aligns itself to the signal beam in order to prevent the voltage variation that may result from minute misalignment of the light source. In this system, a photodiode-array recognizes the central point of the signal beam, and drives motors that correspond to the x and y axes. The photodiode-array aligns itself to the central point of the signal beam, and eliminates the optical noise effect with differential detectioin method. It is very useful in wireless optical interconnections.

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Numerical Study on the Link Range of the IM/DD Wireless Optical Communication at 830[nm] Optical Wavelength using Galilean Optics (갈릴리안 광학계를 사용한 IM/DD 광무선통신 시스템에서 830[nm] 광파장에 대한 전송거리 제한 해석)

  • Hong, Kwon-Eui;Ko, Sung-Won;Cho, Jung-Whan
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.11
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    • pp.123-129
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    • 2011
  • In terrestrial wireless optical communication links, atmospheric effects including turbulence, absorption and scattering have significant impact on the system performance. Based on the analysis of transmission in atmospheric channel concerning 830[nm] wavelength diode laser beam, performance of free space optical (FSO) link utilizing Galilean optics as a laser beam transmitting and receving optics, PIN photodiode as a detecting device. In this paper we designed optical link equation for received optical power and we analyze the atmospheric effects on the signal to noise ratio (SNR) and bit error rate (BER) of an terrestrial FSO system. We show that the possible communication distance for BER=$10^{-9}$ in proposed adverse atmospheric conditions.

Fabrication and Characteristics of an InP Single HBT and Waveguide PD on Double Stacked Layers for an OEMMIC

  • Kim, Hong-Seung;Kim, Hye-Jin;Hong, Sun-Eui;Jung, Dong-Yun;Nam, Eun-Soo
    • ETRI Journal
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    • v.26 no.1
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    • pp.61-64
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    • 2004
  • We have explored the fabrication of an InP/InGaAs single heterojunction bipolar transistor (HBT) and a wave guide p-i-n photodiode (PD) on two kinds of double stacked layers for the implementation of an optoelectronic millimeter-wave monolithic integrated circuit (OEMMIC). We applied a photosensitive polyimide for passivation and integration to overcome the large difference between the HBT and PD layers of around $3{\mu}m$. Our experiment showed that the RF characteristics of the HBT were dependent on the location of the PD layer, while the dc performances of the HBTs and PDs were independent of the type of stacked layer used. The $F_t$ and $F_{max}$ of the HBTs on the HBT/PD stacked layer were 10% lower than those of the HBTs on the PD/HBT stacked layer.

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Ultraviolet Photodetection Properties of ZnO/Si Heterojunction Diodes Fabricated by ALD Technique Without Using a Buffer Layer

  • Hazra, Purnima;Singh, S.K.;Jit, S.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.1
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    • pp.117-123
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    • 2014
  • The fabrication and characterization of a Si/ZnO thin film heterojunction ultraviolet photodiode has been presented in this paper. ZnO thin film of ~100 nm thick was deposited on <100> Silicon (Si) wafer by atomic layer deposition (ALD) technique. The Photoluminescence spectroscopy confirms that as-deposited ZnO thin film has excellent visible-blind UV response with almost no defects in the visible region. The room temperature current-voltage characteristics of the n-ZnO thin film/p-Si photodiodes are measured under an UV illumination of $650{\mu}W$ at 365 nm in the applied voltage range of ${\pm}2V$. The current-voltage characteristics demonstrate an excellent UV photoresponse of the device in its reverse bias operation with a contrast ratio of ~ 1115 and responsivity of ~0.075 A/W at 2 V reverse bias voltage.

A Multi-channel CMOS Feedforward Transimpedance Amplifier Array for LADAR Systems (라이다 시스템용 멀티채널 CMOS 피드포워드 트랜스임피던스 증폭기 어레이)

  • Kim, Seung-Hoon;Park, Sung Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.12
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    • pp.1737-1741
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    • 2015
  • A multi-channel CMOS transimpedance amplifier(TIA) array is realized in a $0.18-{\mu}m$ CMOS technology for the applications of panoramic scan LADAR systems. Each channel consists of a PIN photodiode and a feed-forward TIA that exploits an inverter input stage followed by a feed-forward common-source amplifier so as to achieve lower noise and higher gain than a conventional voltage-mode inverter TIA. Measured results demonstrate that each channel achieves $76-dB{\Omega}$ transimpedance gain, 720-MHz bandwidth, and -20.5-dBm sensitivity for $10^{-9}$ BER. Also, a single channel dissipates the power dissipation of 30 mW from a single 1.8-V supply, and shows less than -33-dB crosstalk between adjacent channels.

Examination of Diffusion Process for High-speed Avalanche Photodiode Fabrication

  • Ilgu Yun;Hyun, Kyujg-Sook;Kwon, Yong-Hwan;Pyun, Kwang-Eui
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.11
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    • pp.954-958
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    • 2000
  • The characterization of zinc diffusion processes applied for high-speed avalanche photodiodes has been examined. The different diffusion process conditions for InP test structures were explored. The zinc diffusion profiles, such as the diffusion depth and the zinc dopant concentration, were examined using secondary ion mass spectrometry with varying the process variables and material parameters. It is observed that the diffusion profiles are severly impacted on the process parameters, such as the amount of Zn$_3$P$_2$ source and the diffusion time, as well as material parameters, such as doping concentration of diffusion layer. These results can be utilized for the high-speed avalanche photodiode fabrication.

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