玻璃表面嵌入式亚微米金属线的制备

提出了一种在玻璃表面制备嵌入式亚微米金属线的方法。首先利用飞秒激光直写技术在玻璃表面烧蚀出亚微米线宽的凹槽,然后采用连续流化学镀工艺在样品表面沉积金属薄膜,再经过热处理和机械抛光,可实现玻璃表面嵌入式亚微米线宽金属结构的可控制备。将飞秒激光烧蚀的阈值效应与连续流化学镀相结合,可制备出最小线宽约为0.66μm的金属银线。四探针法测试结果表明,制备的亚微米金属银线具有良好的导电性,其电阻率约为体积银电阻率的1.2倍。     

光刻1微米线宽的相关技术

光刻技术是发展超大规模集成电路的关键技术。光刻线宽随着DRAM集成的提高而进一步变细,现已突破了0.35微米的屏障。本文论述了曝光系统中镜头的数值孔径,曝光射线的波长及抗蚀剂特性对光刻1微米线宽或亚微米线宽的重要影响。     

千赫兹量级窄线宽半导体激光器研究进展

窄线宽半导体激光器由于其高单色性、低频率噪声、高可调谐性等优点,广泛应用于高速相干光通信、分布式传感、激光雷达等领域.随着高品质因子(Q)光学谐振腔、硅光异构集成芯片等技术的发展,窄线宽半导体激光器近十年经历了革命式发展,线宽压缩至千赫兹(kHz)量级,甚至到亚千赫兹量级.文章阐述了千赫兹量级窄线宽半导体激光器的最新进展,针对不同压缩线宽机制的窄线宽激光器进行了分类介绍,深入讨论了优化耦合系数、减少外腔损耗等对窄线宽激光器性能的影响,并针对未来应用需求展望了千赫兹量级窄线宽激光器在进一步压缩线宽、提升输出光功率方面的发展方向.     

向微米、亚微米进军——日本超大规模集成电路制造设备一瞥

<正> 从某种意义上说,集成电路制造设备就是物化了的集成电路制造技术。本文拟从设备的角度介绍日本超大规模集成电路(VLSI)制造技术的一些近况。目前,日本集成电路企业生产的64KRAM(线宽3～2微米)占世界产量的80％,不少企业又计划在一、两年内开始生产256KRAM(线宽1.5微米)、同时,正在研制中的VLSI的线宽已突破(小于)1微米而进入亚微米的阶段。因此,实现微米,亚微米级微细加工是日本集成电路制造技术面临的中心课题。电子束曝光是突破光波波长的局限,实现亚微米级图形加工的一个基本手段。但是,由于目前的电子束曝光机的加工速度慢,不适于     

利用共焦显微技术测试亚微米尺寸

当集成电路制造工艺线宽进入亚微米领域时，精确、稳定的测试亚微米、深亚微米线宽／间距尺寸，将成为重要而迫切的研究课题。本文主要阐述以光学原理为基础的共焦显微技术，以及利用共焦技术制造的LWM200型测试仪的性能，测试0．5μm，0．3μm的黑／白条宽，及其仪器测试性能分析。     

窄泵浦脉冲对布里渊光时域反射仪测量精度的影响

在窄泵浦脉冲下,由于布里渊散射光的线宽与泵浦脉宽有关,布里渊光时域反射仪(BOTDR)中泵浦脉冲的宽度对BOTDRs的测量精度有影响.本文以数值方法求解了声-光振幅耦合方程,发现当泵浦脉冲的宽度远大于声子寿命时,布里渊散射光的线宽为自然线宽.而当泵浦脉冲的宽度趋于声子寿命时,布里渊散射光的线宽明显增加,从而降低了BOTDR的测量精度.     

准分子激光刻蚀聚合物微图形制作研究

主要描述了紫外准分子激光刻蚀聚酰亚胺(polyimide,PI)制作微图案实验。通过这种刻蚀方法,成功地在PI上制作了微米量级线宽和亚微米量级深度的图案。     

声表面波器件叉指换能器的制作技术

声表面波器件的制造关键在于如何制作叉指换能器，特别对于GHz频率以上的器件,亚微米线宽如何控制是声表器件能否制作成功的关键。本文提供了其制作工艺流程及要点。     

日趋成熟的X射线光刻技术

本文从X射线源、掩模和X射线光刻装置等几个方面,阐述了X射线光刻技术近年来的新进展。并预示了这种新型的亚微米加工技术在八十年代末期可望进入工业化生产0.5微米线宽图形的发展前景。     

基于拉曼泵浦-探测光谱的冷原子温度估算

提出了基于拉曼泵浦-探测技术得到的原子吸收谱线获取冷原子温度的方案,并将其应用于85Rb原子磁光阱中.实验中,原子在囚禁光和探测光的共同作用下发生受激拉曼跃迁,产生亚自然线宽的类色散峰,通过把该类色散峰与理论模型进行拟合估算出被囚禁85Rb冷原子团的温度为230 μK.相对于飞行时间测温法,该方案提供了一种简捷的测量冷原子温度的方法.     

Line shape and atomic efficiency of two-photon absorption using counter-propagating beams to reduce Doppler effects

Doppler effects can be reduced or eliminated for two-photon absorption if the atoms are made to absorb one photon from each of two counter-propagating beams. We derive the line shape for the transition as a function of the frequency difference of the two beams and specifically consider the variation of the linewidth and of the efficiency of utilization of the available atoms.     

Microcavity Laser Linewidth Close to Threshold

Microcavity laser linewidth behavior close to the threshold transition region is investigated through high-resolution linewidth measurements. A local maximum is found for the linewidth of lasers operating slightly above threshold. The increase in laser linewidth close to threshold is explained by the effective contribution of the linewidth enhancement factor ( $alpha $) to the laser linewidth. The Fokker–Planck model of laser noise is then solved using the eigenfunction expansion method to fit to the measured linewidth data. The behavior of the measured linewidth agrees with the model with an extracted linewidth enhancement factor ($alpha $ ) ranging between 3.5 and 5.0.      

Spectral linewidth of AlGaAs/GaAs surface-emitting laser

The spectral linewidth Delta nu of a vertical cavity surface-emitting (SE) laser was measured for the first time. The linewidth measured by a delayed self-homodyne method was 50 MHz at an output power of 1.4 mW under room-temperature CW operation. The linewidth obtained was guite narrow in spite of the short cavity configuration of the SE laser. This narrow linewidth is attributed to the high-reflectivity mirrors. The measured linewidth is in good agreement with theoretical values.<>     

有源光纤环形腔的频率滤波特性

本文首先从理论上通过简单的分析得以了有源光纤环形腔的输出谱密度函数公式，该式清楚地表明光纤环形腔的频率滤波特性。从该公式出发，详细分析了环形腔输入光纤宽和环形腔参数对输出光谱谱型和线宽的影响。最后，通过设计不同的环形腔的自由谱宽和不同线宽的激光器作为输出光源，对上述理论分析做了实验验证。理论和实验表明，由于环形腔的强度传递函数是多峰的响应函数，环形腔自由谱宽和输入激光线宽的大小直接影响到环形腔输出光频谱形状，即是单峰输出还是多峰输出，对于不同形状的光谱输出，输出激光的线宽受环形腔的参数影响也各不相同。     

The semiconductor laser linewidth due to the presence of side modes

The laser linewidth is evaluated by solving the rate equations for a nearly single-mode laser with two modes. The resulting linewidth contribution due to the presence of side modes is introduced by the nonlinear gain in the laser diode. For weak side modes, the linewidth contribution is proportional to the third power of the side mode intensity. A linewidth contribution of about 20 MHz for a side-mode power of 100 μW has been found experimentally for a 1.3-μm buried-heterostructure laser     

The optimal loop gain design for the spectral linewidth reductionin an electrical feedback semiconductor laser

The design of the optimal feedback loop gain for the spectral linewidth reduction in a semiconductor laser with electrical feedback is presented using a model of self-heterodyne type electrical feedback. The results show that the feedback loop gain must be suitably chosen to satisfy the requirement of narrowing linewidth. Due to the influence of AM noise in the feedback process, there is an optimal value for the feedback loop gain to reduce the linewidth for a given feedback condition. The influence of other feedback parameters on the linewidth reduction is also presented     

Analysis of linewidth of separated-electrode DFB laser diode

Presents a new linewidth formula for DFB lasers, which includes the spatial hole burning effect. The linewidth of DFB lasers with three separated electrodes is calculated in various bias conditions. The optimum bias condition is discussed to obtain a narrow linewidth.<>     

Correlation of relative intensity noise with linewidth floors in narrow linewidth DFB lasers

The relative intensity noise of narrow linewidth DFB lasers in the vicinity of linewidth floors is measured. A strong correlation between linewidth rebroadening and a corresponding increase in the relative intensity noise for frequencies below 3 GHz is observed for devices with mode suppression ratios in excess of 35 dB.<>     

差频产生中红外光源的线宽分析

差频法具有无需复杂腔型调整、输出激光调谐范围宽、效率较高等综合优点,是获得3～5μm中红外激光光源的重要手段。推导了差频产生中红外激光的输出光波长、线宽以及功率的公式,重点讨论了输出激光线宽与抽运光波长和线宽、信号光线宽以及温度等因素的关系。结果表明,输出激光线宽主要由抽运光和信号光的线宽决定。     

RF Linewidth in Monolithic Passively Mode-Locked Semiconductor Laser

We have analyzed theoretically and experimentally the linewidth of the first harmonic of the photocurrent (radio-frequency (RF) linewidth) in monolithic passively mode-locked semiconductor lasers. Due to the absence of restoring force, the timing jitter is directly related to the RF linewidth, avoiding possible underestimations made with conventional methods of phase noise measurement. The RF linewidth is also analytically related to the pulse characteristics using Haus's model. The timing stability performance of a promising two-section quantum-dot laser is presented using RF linewidth measurements. Experimental evolution of the RF linewidth with power and pulsewidth is finally compared to the analytical expression.