精细电路连接用紫外光固化各向异性导电胶

为适应高密度超细线路连接的需要,研究了紫外光固化各向异性导电胶。得到了可以用UV(紫外光)有效固化的各向异性导电胶(ACA)。通过对固化过程和应用于氧化铟锡连接实验的分析,研究了各组分在体系中的作用和添加量对导电胶的连接性能和导电性能的影响。结果表明,紫外光固化各向异性导电胶为液晶显示(LCD)和电致发光显示(ELD)技术提供了一种新的连接方式。     

Curing Behaviors of UV-Curable Temporary Adhesives for a 3D Multichip Package Process

Temporary bonding adhesives for a three-dimensional (3D) multichip package process have been synthesized. To enhance the thermal stability, the adhesives used a fluorinated silicon urethane acrylic binder and ultraviolet (UV) curing for crosslinked network structures. Focusing on different photoinitiator contents and UV doses, the UV-curing behaviors and thermal stability were studied using Fourier-transform infrared spectroscopy attenuated total reflectance, gel fraction, swelling ratio, shrinkage, and thermogravimetric analyses.     

富勒烯衍生物的超快光限幅特性研究

应用倍频Ｎｄ：ＹＡＧ脉冲激光，在波长为５３２ｎｍ，脉冲宽庶２３ｐｓ的条件下，研究了面式和径式－「双（１，２－二本基膦基）－２」（三羰基）（η＾２－Ｃ６０）铬（ｆａｃ－ａｎｄ ｍｅｒ－「ｂｉｓ（１，２－ｄｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｏ）ｅｔｈａｎｅ」（ｔｒｉｃａｒｂｏｎｙｌ）η＾２－ｆｕｌｌｅｒｅｎｅ－Ｃ６０）ｃｈｒｏｍｉｕｍ）的光限幅特性。并应用单重态激发态吸收理论对实验结果进行了分析，实验结果     

Nearly Shot-Noise-Limited Performance of Dual-Channel Linear Optical Sampling for Ultrafast DPSK Signals

This paper describes a newly developed dual-channel linear optical sampling technique for observing ultrafast optical differential phase-shift keying (DPSK) signals. As the proposed measurement scheme offsets two parallel interferometers by a relative delay corresponding to 1-symbol length of the DPSK signal, the measured phase distribution reflects the signal quality which is determined by the phase difference between adjacent symbols. This technique, based on interferometric optical gating by local short-pulses, also offers ultrafast measurement at symbol rates of greater than 100 Gsymbol/s. Moreover, its detection sensitivity can reach the shot noise limit. The waveform degradation caused by the coherence of the light source and the pattern effect of the phase modulator is successfully observed in continuous waves and 10-Gsymbol/s nonreturn-to-zero DPSK signals, and the constellation measurement is demonstrated for a 160-Gsymbol/s return-to-zero DPSK signal. Measurement system noise is also discussed for characterizing the detection sensitivity, and the nearly shot-noise-limited performance is experimentally verified.      

Ultrafast All-Optical Processor Based on Quantum-Dot Semiconductor Optical Amplifiers

We have developed a theoretical model of an ultrafast all-optical signal processor based on the Mach–Zehnder interferometer with quantum—dot semiconductor optical amplifiers in both its arms. It is shown that such a processor under different conditions may realize wavelength conversion, xor logic operation, and optical 3R regeneration.      

Investigation of Patterning Effects in Ultrafast SOA-Based Optical Switches

Ultrafast optical switching employing semiconductor optical amplifier (SOA) based optical switches has been demonstrated at bitrates up to 640 Gbit/s. However, patterning effects caused by relatively slow recovery processes in semiconductor structures remain as an important deteriorating factor that limits the ultimate speed at which SOA-based switches can be operated. In this paper, we investigate the patterning effects of SOA-based switches using a systematic approach. A simple condition for the lower bound limit of the bit pattern length that should be adopted in the performance evaluations of the switches is derived. It is shown that the minimum bit pattern length scales linearly with the bitrate and the recovery time of the SOA. To overcome the excessive computation time needed for numerical analysis at long pseudorandom binary sequence (PRBS) lengths, an effective method, i.e., periodic method, has been proposed based on the idea of driving the SOA at two saturation extremes by two periodic pulse trains. The predictive power of the periodic method is verified by comparing its results with those obtained by using ordinary PRBS patterns. Finally, the effectiveness of the periodic method is exploited by analyzing in detail the performance properties of a specific type of switch over large parameter regions. Besides allowing an investigation of patterning effects, the periodic method also simultaneously provides such figures of merit as output power and pulsewidth.      

Ultrafast Measurement of Optical DPSK Signals Using 1-Symbol Delayed Dual-Channel Linear Optical Sampling

We propose and demonstrate a 1-symbol delayed dual-channel linear optical sampling for observing optical differential phase-shift keying (DPSK) signals. As this technique is based on optical gate processing by means of interference with local short pulses, its performance allows ultrafast measurement for a symbol rate of greater than 100 Gsymbol/s. Moreover, as the new measurement apparatus employs a two-series interferometer system with a 1-symbol delay, the measured phase distribution reflects the signal quality between adjacent symbols of the optical DPSK signals. In our experiment, we successfully observe the waveform degradation caused by the coherence of the light source and the pattern effect of the phase modulator. The measurement system noise is also discussed.     

超快时间分辨漫反射法组织光学特性的测量

本文简要介绍一种以时域中的漫射理论为基础，应用超快技术测量漫反射度曲线Ｒ（ρ，ｔ）获得组织吸收系数μ２和传输散射系数μ＇５的方法，该法可望在临床上无损、快速、实时地测量活体组织光学特性，将具有广泛的应用前景。     

Highly Functional All-Optical Control Using Ultrafast Nonlinear Effects in Optical Fibers

Using the optical fibers and ultrashort pulses, we can demonstrate highly functional optical control. We have succeeded in generation of low-noise, ultraflat, high-quality supercontinuum (SC). Recently, octave spanning high-quality SC is also generated. The carrier envelope offset frequency measurement and ultrahigh resolution optical coherence tomography are demonstrated using SC. We can also generate widely wavelength-tunable ultrashort soliton pulses using soliton self-frequency shift (SSFS). So far, several new techniques have been proposed and demonstrated using SSFS. The author has also discovered novel two-pulse trapping phenomena. The ultrafast all-optical switching is demonstrated using the pulse trapping techniques, and principles and characteristics are described.      

Ultrafast Switchable Passive Radiative Cooling Smart Windows with Synergistic Optical Modulation

Switchable passive radiative cooling (PRC) smart windows can modulate sunlight transmission and spontaneously emit heat to outer space through atmospheric transparent window, presenting great potential in building energy conservation. However, realizing stable and on-demand control of the cooling efficiency for PRC materials is still challenging. Herein, an electro-controlled polymer-dispersed liquid crystal (PDLC) smart window showing PRC property is designed and prepared by adding mid-infrared emitting reactive monomers into the conventional PDLC matrix. It is found that not only the electro-optical properties but also the PRC efficiency of PRC PDLC film are tunable by regulating the content of the mid-infrared emitting components, film thickness, and micromorphology. This advanced PRC PDLC material achieves a near/sub-ambient temperature when the solar irradiance is below 400 W m⁻² and can dynamically manage daytime cooling efficiency. Importantly, its PRC efficiency is capable of being tuned in an on-demand and ultrafast millisecond-scale way, whose controllable transparency enables multistage heat regulation. This study is hoped to provide new inspiration in the preparation of advanced optical devices and energy-efficient equipment.     

胶粘剂及其涂覆工艺

在波峰焊及回流焊过程中使用胶粘剂,以保持SMD（表面贴装器件）在PCB上的位置及方向。胶粘剂必须能适应使用高温焊接料及助焊接、清洗剂时的环境,还不能影响电路的性能。因此,选择合适的胶粘剂与涂敷工艺是非常重要的。     

Background-Suppressed Ultrafast Optical Sampling Using Nondegenerate Two-Photon Absorption in a GaAs Photodiode

We describe an ultrafast optical sampling system that uses nondegenerate two-photon absorption (2PA) in a GaAs photodiode. By choosing the sampling pulses to have a photon energy below the half-bandgap, we successfully suppress the otherwise large photocurrent associated with 2PA of the strong sampling pulses. Using this approach, we demonstrate a background-suppressed measurement of quasi-4-Tb/s eye diagrams, with temporal resolution that is limited by the sampling pulsewidth.      

基于光克尔门技术的超快时间分辨测量系统的优化

以SrTiO3晶体作为光克尔介质,建立了一套基于光克尔门技术的超快时间分辨测量系统.由于SrTiO3晶体在强光作用下产生光克尔效应时,同时会产生宽谱带的双光子激发荧光,因此我们一方面通过采用锁相放大探测技术从同频率的荧光背景中提取信号光,另一方面通过设计自动数据采集系统提高测量效率.为避免背景荧光以及泵浦光散射等噪声对光电倍增管的曝光而造成的探测器对信号光的非线性响应,我们通过增加SrTiO<,3>晶体与探测器之间的距离以及采用封闭信号光路来减少因此而造成的测量误差.以小于150 fs波长为800 nm的激光脉冲作为泵浦光,其倍频光作为信号光,采用该系统实验得到了约200 fs的时间分辨率.     

40 Gb/s超快非线性干涉仪的实验分析

全光非线性开关是全光3R再生的关键技术。在对一种全光开关[超快非线性干涉仪(UNI）]的传输函数进行分析后，得到了超快非线性干涉仪窗口的数学描述。在此基础上通过实验得到了40Gb／s的全光开关。并结合实验条件，具体分析了影响超快非线性干涉仪开关窗口的几个因素：增加半导体光放大器(SOA)的注入电流，增大控制脉冲的平均功率和调节连续光功率到最佳值。都能有效地改善输出窗口的形状和消光比，并对这种现象在理论上进行了初步分析。可以利用上述结论指导超快非线性干涉仪实验，从而使超快非线性干涉仪系统得到最大程度的优化。     

Ultrafast Time-Spread Optical BPSK Code Label Generation and Processing Based on Variable-Bandwidth Spectrum Shaper

In experiments, we demonstrated time-spread 200-Gchip/s 10-Gb/s eight-chip optical binary phase-shift keying code generation and matched filtering based on spectral amplitude and phase control. By using a bandwidth-tunable high-resolution optical spectrum controller that we have previously developed, we were able to control spectral components with 10-GHz resolution in the entire $C$-band, with rectangular passbands. To demonstrate the application of this spectrum controller to tunable optical label processing, we performed experiments and simulated label generation and processing by controlling the spectrum.      

Trigger-Detachable Hydrogel Adhesives for Bioelectronic Interfaces

Recent electronics technology development has provided unprecedented opportunities for enabling implantable bioelectronics for long-term disease monitoring and treatment. Current electronics-tissue interfaces are characterized by weak physical interactions, suffering from potential interfacial failure or dislocation during long-term application. On the other hand, some new technologies can be used to achieve robust electronics-tissue interfaces; however, such technologies are limited by potential risks and the discomfort associated with postdetachment of the bioelectronics. Here, a hydrogel-based electronics-tissue interface based on the exploitation of dynamic interactions (such as boronate-diol complexation) that features an interfacial toughness over 400 J m⁻² is presented. Moreover, these hydrogel adhesion layers are also trigger-detachable by dissociating the dynamic complexes (i.e., addition of glucose). These hydrogel-based bioelectronic interfaces enable the in vivo recording of physiological signals (i.e., electromyograph, blood pressure, or pulse rates). Upon mild triggering, these bioelectronics can be easily detached without causing any damage, trauma, or discomfort to the skin, tissues, and organs. This kind of trigger-detachable hydrogel adhesives offer general applicability in bioelectronic interfaces, exhibiting promising utility in monitoring, modulating, and treating diseases where temporary monitoring of physiologic signals, interfacial robustness, and postremoval of bioelectronics are required.     

激光割胶工艺研究

激光割胶,是一种可以完美替代传统印制插头板手工割胶制程的新工艺。该工艺采用激光等光、机、电一体化控制技术,实现贴胶印制插头板的高效率、高精度割胶制程,可以节省大量人工,并且非常稳定地进行蓝胶的盲切,精度达到±0.1mm,提高产品的良品率,满足PCB行业的生产需求。     

Generation of Arbitrary Sequences of Ultrafast Pulses With Integrated-Optic Space-to-Time Optical Processors and Phase-Only Masks

We report a new approach to the generation of arbitrary sequences of ultrafast pulses using an integrated optics space-to-time optical processor. The processor combines a reflective arrayed waveguide grating multiplexer with a phase-only mask containing sets of pixels of constant phase separated by sets of pixels with phases alternating between 0 and pi rad     

微电子封装用导电胶的研究进展

介绍了导电胶的组成、分类及与传统锡-铅焊料相比导电胶的优点。阐述了导电胶的导电机理、失效机理以及国内外的研究现状。