High speed SOI CMOS image sensor with pinned photodiode on handle wafer

We have fabricated SOI CMOS active pixel image sensor with pinned photodiode on handle wafer. The structure of one pixel is a four-transistor type active pixel image sensor, which consists of a reset and a source follower transistor on seed wafer, and is comprised of a photodiode, a transfer gate, and a floating diffusion on handle wafer. The photodiode could be optimized for better quantum efficiency and low dark currents because the process of a photodiode on handle wafer is independent of that of transistors on seed wafer. Most of the wavelengths are absorbed within the visible range, because the optimized photodiode is located on the handle wafer. The response time of SOI CMOS active pixel sensor was about 2 times faster than that of bulk CMOS active pixel image sensor.     

Single-photon time response of reach-through APD

Time response of avalanche photodiode (APD) is very important in photon counting systems, and there are many models for circuit simulation. But these studies generally based on the carrier rate equations of steady-state condition, disagree with the single-photon-indicate condition. In this paper, a time response function based on an integration of APD’s sub-domain carriers for reach-through APD arising from a single photo-carrier is derived. The analytical results are shown to be in good accord with experimental results.     

Self-organized Criticality in Hierarchical Brain Network

It is shown that the cortical brain network of the macaque displays a hierarchically clustered organization and the neuron network shows small-world properties. Now the two factors will be considered in our model and the dynamical behavior of the model will be studied. We study the characters of the model and find that the distribution of avalanche size of the model follows power-law behavior.     

新结构雪崩光探测器的特性仿真及后工艺优化

报道了一种在倍增区引入AlxGa1-xAs带隙梯度结构的谐振腔增强型雪崩光探测器,并提出优化其后工艺制作的新方法.通过将Al0.4Ga0.6As(28 nm)一Al0.2Ga0.8As(10 nm)-GaAs(50 nm)带隙梯度结引入雪崩探测器的高场区,可以实现对探测器噪声和频率响应两个主要性能的优化.数值仿真表明,该结构探测器具有较小的噪声(有效离化系数为0.1),约33 GHz的3 dB带宽(增益为5),在增益为15时可获得420 GHz的增益带宽积.在实际的后工艺制作中,提出使用苯并环丁烯树脂进行InP/空气隙DBR反射镜与雪崩探测器结构粘合的方法,简化了工艺流程.

摘要：

     

1Gb/s CMOS调节型共源共栅光接收机

基于特许0.35μm EEPROM CMOS标准工艺设计了一种单片集成光接收机芯片,集成了双光电探测器(DPD)、调节型共源共栅(RGC)跨阻前置放大器(TIA)、三级限幅放大器(LA,limiting amplifier)和输出电路,其中RGCTIA能够隔离光电二极管的电容影响,并可以有效地扩展光接收机的带宽。测试结果表明,光接收机的3dB带宽为821MHz,在误码率为10-9、灵敏度为-11dBm的条件下,光接收机的数据传输速率达到了1Gb/s;在3.3V电压下工作,芯片的功耗为54mW。     

高温环境中光触发开关的设计

 针对在高温环境中测试仪器的供电方式问题,利用光敏二极管响应时间短并对光灵敏的优点,将其作为供电电源的开关,吸收高温辐射源发出的红外光信号,通过光电转换,使电源导通,达到开关的效果。文中阐述了这种光控的供电方式的理论依据和实现方式,排除了日光等因素的干扰,并对该方法进行了验证。通过试验证明,该方法操作简单,实用性强,很适用于一些不适合人为操作的场合。     

Full‐duplex analogue/digital data transmission using lasers coupled to GI fibre and its application

This paper describes a low‐cost version of a full‐duplex optical fibre analogue/digital data transmission link whose practical implementation is simplified by using a pair of laser diodes, each having a built‐in photodiode for monitoring the laser output power, and its application to vibration test data transmission. The transmission link sends digital data of up to 9600 bps in one direction, and analogue data of DC to 100 kHz and image data specified by an NTSC colour video signal in the opposite direction, all at the same time through one GI optical fibre. Being simple in configuration and stable against noise, this type of link has a variety of applications within factory, home and offices. Copyright © 2001 John Wiley & Sons, Ltd.     

氦氖激光纵模脉冲检测及其数据处理

在分析常用低噪声快速光电探测器的基础上,选择PIN光电二极管来探测氦氖激光纵模脉冲。通过合理设计降低前放电路的噪声,根据被测脉冲频率设计探测电路的带宽,达到提高信噪比的目的。同时在后端的数据处理中,根据激光脉冲的波形函数,利用曲线拟合的方法来进一步去除测量中的各种噪声,从而准确地了解脉冲的形状、相位等信息,大大地提高了在现有硬件设备条件下测量的准确性,减小了测量误差。     

Radiation damage in Si photodiodes by high-temperature irradiation

Results are presented of a detailed study of the effects of high-temperature 4-MeV neutron irradiation on the performance degradation of Si pin photodiodes together with the radiation-induced defects, observed by deep level transient spectroscopy. The degradation of the device performance and the introduction rate of the lattice defects decrease with increasing sample temperature during irradiation. For a 250°C irradiation, the reduction of the reverse current is only 20% of the starting value. This result suggests that the creation and recovery of the radiation damage proceeds simultaneously at high temperatures. Carbon-related complex as hole capture levels is also mainly responsible for the device degradation for high-temperature neutron irradiation.     

双极RF功率管的深阱结终端

给出了双极 RF功率管新的深阱结终端结构 .模拟分析表明 ,具有优化宽度、优化深度且填充绝缘介质的深阱结终端结构能使雪崩击穿电压提高到理想值的 95 %以上 .实验结果表明 ,深阱结终端结构器件 DCT2 6 0的BVCBO为理想值的 94 % ,比传统终端结构器件高 14 % ;与传统结构相比 ,在不减小散热面积的情况下 ,该结构还减小集电结面积和漏电流 ,器件的截止频率提高 33% ,功率增益提高 1d B