多功能有源激光微调机的系统设计

针对厚膜混合集成电路的功能微调需求,设计了一种多功能有源激光微调机。通过在线测量不同的产品参数,可实现多功能激光微调,其中包括输出电压修调,保护电流修调和信号电路调整(调测占空比、频率和相位)。本文重点介绍了多功能有源激光微调机的控制系统,通过分析测量步长和减速精度对修调精度和修调效率的影响,进而提出了自动修调方法中兼顾精度和效率的参数设置方法。多功能有源激光微调机很好地满足了国内厚膜混合集成电路功能微调需求。     

微电子工业中的一种新型激光调修技术

新型激光调修技术与常规的CMOS处理方法完全兼容。用这种方法既可以调修模拟器件，也可以调修模拟和数字混合的微电子器件。该方法是用一束激光烧熔硅体，使两个p-n结二极管之间形成电连接而产生一个电阻器件。在自动设备系统中，1s内就可生产出这种激光扩散电阻，其阻值范围从100Ω到几MΩ，激光的重复调修过程可使电阻精度达到50ppm。用这种方法也可做出温度系数接近0的电阻。本文主要阐述生产这种电阻的方法、主要器件和有关处理方式的关键点。     

一种高精度快速激光修调方案设计

在激光修调过程中,激光的修调路径和控制策略是影响修调精度和修调速度的关键因素,而常规激光修调方案难以同时满足高精度和快速修调。因此,提出了一种高精度快速激光修调方案,使用“离散+连续”结构的金属薄膜电阻图形提高修调效率和可靠性;利用阶梯形的激光修调路径提升修调精度;采用动态测试步长的控制策略提高修调速度。采用上述方案对60个金属薄膜电阻样品进行激光修调,结果表明：修调精度可达0.004%,平均测试步长为2.53,验证了所提出的修调方案可有效提升修调精度和修调速度。进一步将该方案应用在200个温度传感器芯片的校准中,结果表明200个温度传感器芯片的测温误差均校准至±0.2℃以内,平均测试步长为6.29。     

激光修调对CrSi薄膜电阻稳定性的影响

该文分析了激光修调对CrSi薄膜电阻稳定性的影响,获得了对CrSi薄膜电阻进行激光修调的优化方法.实验结果表明,150 ℃储存48 h,可完全消除激光修调带来的影响,使CrSi薄膜电阻温度系数降到了20×10-6/℃,提高了CrSi薄膜电阻网络的稳定性,从而为研制高性能模拟集成电路打下坚实的基础.     

基于自适应测量步长的激光调阻控制策略

针对0603型片式电阻在不同位置的阻值变化率不同,提出了基于自适应测量步长的激光调阻控制策略。这种调阻控制策略可根据当前阻值与目标值的偏差百分比自适应选择测量步长。经过实验分析,与固定测量步长的控制策略相比,这种控制策略不仅能够保证激光修调精度也能提高激光修调效率。为了使这种控制策略能够广泛应用于不同电阻型号的激光修调,介绍了自适应测量步长控制策略的建模过程,在不了解刻蚀路径对阻值变化率的影响时可建模之后再应用这种控制策略。     

微电子学、集成电路

TN4 2003040484信总例代最三要的荃石一徽电子/陆剑侠,李树良(东北微电子所)}I微处理机.一2002,(2)一1一3分析了国际国内微电子行业市场情况,着重阐述了微电子行业在信息时代的重要作用.最后,展望了国内微电子行业的发展前景.表2参5(刚)可以调修模拟器件,也可以调修模拟和数字混合的微电子器件.该方法是用一束激光烧熔硅体,使两个P-n结二极管之间形成电连接而产生一个电阻器件.在自动设备系统中,ls内就可生产出这种激光扩散电阻,其阻值范围从100几到几Mfl,激光的重复调修过程可使电阻精度达到50ppm.用这种方法也可做出温度系数接近O的电…     

TureType字库在激光调阻机中的应用

为了获得一种用于自动激光调阻机中的激光打标系统,选用VB程序设计语言并采用API函数从TureType字库中提取字符信息,将字符信息保存为激光调阻机可读取的文件,以激光划线和激光扫描打点的方式打印空心字和实心字,并将激光打印程序指令化。结果表明使用API函数可以方便地提取字符信息和进行各种字符格式的变换,该系统已经运用到自动激光调阻机中。     

基于厚膜混合集成电路的激光调阻工艺研究

激光调阻具有高精度、高效率等特点,是目前厚膜混合集成电路最为常用的电阻修调方法。为了实现厚膜混合集成电路中精度电阻的制作,文章对激光调阻工艺进行了系统研究,内容包括探针卡焊接组装、调阻程序编制以及工艺试验研究。通过进行试验验证,选用L型调阻路径,调阻精度已达到±0.5%,满足设计要求。     

不同波长激光电阻修调的对比研究

微电子线路的被动或主动元件的激光修调技术，经过二十多年的实践已经发展成一项成熟技术了。在生产精确的混合信号、线性和被动网络方面，该项技术已成为必要工序。由于市场要求器件的尺寸更小、性能更高，因此在大多数情况下必须用激光来精确修调电路。同时，被修调的元件尺寸越来越小，公差越来越严格，也推动了激光修调技术走向更高水平。传统的1m激光波长产生的光斑尺寸及其热影响区域（HAZ），可能不够小，不足以维持电阻的稳定性，也难以使阻值温度系数（TCR）的漂移和改变降到最小。 本文研究了用更短波长的激光进行电阻修调，并将结果与传统的1m波长的修调技术作了比较。     

激光调阻机的光学系统设计

激光调阻机是通过激光打点切割,改变电阻体的导电截面积,从而达到把低于目标阻值的电阻体阻值修调到要求阻值允许的偏差范围内,适用于片状电阻器的快速大规模生产.在激光调阻过程中,通过高精度的数字电桥实时监测阻值变化,控制调阻进程,辅之以系统复杂的机械手操作,脉冲激光器高频输出,光束精确定位控制及其它机电操作控制,自动完成每小时十几万支电阻的调修生产,是集光、机、电一体的现代化高科技生产设备.调阻机光学系统主要由三部分组成:1)光源系统,2)光束扫描系统,3)光学监视系统.光源系统包括激光器、光束能量衰减器、扩束器等.作为激光调阻机的加工用光源,其特性参数对调阻效率、精度有直接影响,本机采用Nd∶YAG声光调Q脉冲固体激光器,光束模式为TEM00模.激光调阻时,薄膜电阻材质不同,所需要的激光功率也不同,通过在光路中加入衰减片的方法,可获得稳定的调阻功率.光束扫描系统由双向扫描振镜和聚焦f-θ透镜组构成,前者实现光束按要求偏转,后者对光束进行聚焦,使其焦点位于电阻片表面.聚焦镜头由多片透镜组成,除有普通光学系统的一般要求外,还要求该镜组达到扫描距离与扫描角度成线性关系.光学监视系统包括分光镜、变焦镜头、CCD相机和照明光源等.分光镜经过特殊镀膜处理,以实现对不同波长光的透过及反射要求.调阻用的激光是单色光,f-θ聚焦镜组在设计时无须考虑消色差.照明光源采用高亮度红光二极管,可获得清晰的观察效果.(OE33)     

A novel tunable transmission line and its application to a phase shifter

This letter describes the design of a novel transmission line, where characteristic impedance can be adjusted electronically, and its application to a phase shifter. A tunable transmission line enables microwave circuit designers to have flexibility and better return loss which can enhance its tuning range. A UHF band distributed analog phase shifter, as well as a tunable transmission line, is presented. The characteristic impedance of a fabricated novel transmission line varies from 10 to 69.5/spl Omega/, which demonstrates its tunability, and the fabricated UHF phase shifter using this novel line shows the possibility of better reflection coefficient and wider tuning range over the conventional capacitively-loaded distributed phase shifter.     

Development of multiband phase shifters in 180-nm RF CMOS technology with active loss compensation

We present the design and development of a novel integrated multiband phase shifter that has an embedded distributed amplifier for loss compensation in 0.18-/spl mu/m RF CMOS technology. The phase shifter achieves a measured 180/spl deg/ phase tuning range in a 2.4-GHz band and a measured 360/spl deg/ phase tuning range in both 3.5- and 5.8-GHz bands. The gain in the 2.4-GHz band varies from 0.14 to 6.6 dB during phase tuning. The insertion loss varies from -3.7 dB to 5.4-dB gain and -4.5 dB to 2.1-dB gain in the 3.5- and 5.8-GHz bands, respectively. The gain variation can be calibrated by adaptively tuning the bias condition of the embedded amplifier to yield a flat gain during phase tuning. The return loss is less than -10 dB at all conditions. The chip size is 1200 /spl mu/m/spl times/2300 /spl mu/m including pads.     

Optimizing polarization states in a figure-8 laser using anonreciprocal phase shifter

The polarization states in a figure and laser are analyzed using Jones matrices. The analysis shows that a figure-8 laser in CW operation does not give enough information to allow the optimization of the birefringence for mode-locking. A switchable nonreciprocal phase shifter is proposed to provide a simple way to optimize the birefringence for a mode-locked figure-8 laser. Using this device, the mode-locking of a diode-pumped figure-8 laser was started, with a probability better than 99%, by following a sequence of predetermined mechanical adjustment. With the proposed nonreciprocal phase shifter, the optimization and starting of a figure-8 laser can easily be automated     

On the feasibility of CMOS multiband phase shifters for multiple-antenna transmitters

We present the design of an integrated multiband phase shifter in RF CMOS technology for phased array transmitters. The phase shifter has an embedded classical distributed amplifier for loss compensation. The phase shifter achieves a more than 180/spl deg/ phase tuning range in a 2.4-GHz band and a measured more than 360/spl deg/ phase tuning range in both 3.5-GHz and 5.8-GHz bands. The return loss is less than -10dB at all conditions. The feasibility for transmitter applications is verified through measurements. The output power at a 1-dB compression point (P/sub 1 dB/) is as high as 0.4dBmat 2.4GHz. The relative phase deviation around P/sub 1 dB/ is less than 3/spl deg/. The design is implemented in 0.18-/spl mu/mRF CMOS technology, and the chip size is 1200/spl mu/m /spl times/ 2300 /spl mu/m including pads.     

一种S频段反射型可调模拟移相器的设计

设计了一种应用于S频段卫星通信相控阵系统的反射型可调模拟移相器。该移相器利用三分支线定向耦合器扩展了带宽,改善了工作频段内驻波;采用传输线和变容二极管构成的L型反射负载扩大了相移量。测试结果表明,在上行频段1.98～2.01 GHz内,相移量达到191°±1°,在下行频段2.17～2.2 GHz内,相移量达到186°±0.1°;插入损耗优于3.3 dB且插入损耗波动小于1 dB,回波损耗在整个电压调谐范围内均大于20 dB。该移相器结构简单、便于调节且价格低廉,在卫星通信领域有一定的应用价值。     

Distributed MEMS analog phase shifter with enhanced tuning

The design, fabrication, and measurement of a tunable microwave phase shifter is described. The phase shifter combines two techniques: a distributed capacitance transmission line phase shifter, and a large tuning range radio frequency (RF) microelectromechanical system (MEMS) capacitor. The resulting device is a large bandwidth, continuously tunable, low-loss phase shifter, with state-of-the-art performance. Measurements indicate analog tuning of 170/spl deg/ phase shift per dB loss is possible at 40 GHz, with a 538/spl deg/ phase shift per centimeter. The structure is realized with high-Q MEMS varactors, capable of tuning C/sub max//C/sub min/= 3.4. To our knowledge, this presents the lowest loss analog millimeter wave phase shifter performance to date.     

A 0.13-μ m CMOS Phase Shifter Using Tunable Positive/Negative Refractive Index Transmission Lines

This letter presents a tunable positive/negative refractive index transmission line (TL) phase shifter utilizing active circuits. It comprises a microstrip TL loaded with series varactors and a shunt monolithic microwave integrated circuit (MMIC) to synthesize a tunable inductor. This implementation increases the phase tuning range and maintains the input and output matching of the phase shifter across the entire phase tuning range, while eliminating the need for bulky passive inductors. The phase shifter is capable of providing both positive and negative phase shifts. The MMIC tunable inductors are fabricated in a 0.13-mum CMOS process and operate from a 1.5-V supply. The phase shifter achieves a phase of -40deg to +34deg at 2.5GHz from a single stage with less than -19dB return loss, and better than 1.1-dB insertion loss at 2.5 GHz. The phase shifter has a 1-GHz bandwidth over which the return loss remains better than 12.1dB     

Printed and Integrated CMOS Positive/Negative Refractive-Index Phase Shifters Using Tunable Active Inductors

This paper presents a printed and an integrated bi-directional tunable positive/negative refractive-index phase shifter utilizing CMOS tunable active inductors (TAIs). The printed phase shifter is comprised of a microstrip transmission line (TL), loaded with series varactors and a shunt monolithic microwave integrated circuit (MMIC) synthesizing the TAI. Using the TAI extends the phase tuning range and results in a low return loss across the entire tuning range. The integrated circuit (IC) phase shifter replaces the TLs with suitable lumped L-C sections. This enables integrating the entire phase shifter on a single MMIC, resulting in a compact implementation. The TAI used for both phase shifters is based on a modified gyrator-C architecture, employing a variable resistance to independently control the inductance and quality factor. The TAI is fabricated in the 0.13-mum CMOS process and operates from a 1.5-V supply. The TAI chip is used to implement the TL phase shifter, which achieves a phase of -40deg to +34deg at 2.5 GHz with less than -19-dB return loss from a single stage occupying 10.8 mm times 10.4 mm. The IC phase shifter is fabricated in the same process and achieves a phase from -35deg to +59deg at 2.6 GHz with less than -19-dB return loss from a single stage occupying 550 mum times 1300 mum.     

A Simple Tuning Circuit for Waveguide and Transmission Line Systems (Correspondence)

A simple tuning circuit for source or load matching is described that makes possible smooth and sensitive adjustments with no "holes" in frequency coverage over a complete waveguide band. Energy is coupled out of the mainline, the phase and magnitude adjusted with phase shifter and attenuator and fed back into the mainline to cancel the reflected signal. A simple analysis of the circuit is presented, and a graph given for estimating the maximum voltage standing-wave (VSWR) that can be "tuned out." Application to measurement of reflection coefficient or to impedance is proposed.