基于QFP技术的高频集成电路封装设计

通过对标准QFP引线框架的改造,实现了一种高频集成电路芯片的封装设计。介绍了利用电磁场仿真软件进行封装的3D建模,并提取封装结构的模型参数,进行信号完整性分析的方法。实例验证表明,此方法以较低的封装成本,较好地减少了长键合线及框架引脚对高频信号的影响,在现有的封装技术基础上提供了实现高频/高速集成电路封装的新思路。     

基于CQFP 64线外壳的封装寄生参数研究

封装寄生效应对高频器件性能的影响越来越明显.为了在高频器件设计中充分考虑寄生参数的影响,需对封装的寄生效应进行模拟,以便保持高频电路封装后信号的完整性.利用Anfost公司的软件Q3D和HFSS,对CQFP 64管壳的引脚和键合线进行电磁仿真分析,提取出三维封装结构的RLC参数和高频下的S参数;分析管壳在封装前后、不同频率、不同封装环境下寄生参数的变化情况;将仿真结果与实验结果进行了对比,为设计人员设计产品提供依据.     

高速BGA封装与PCB差分互连结构的设计与优化

随着电子系统通信速率的不断提升,BGA封装与PCB互连区域的信号完整性问题越来越突出。针对高速BGA封装与PCB差分互连结构进行设计与优化,着重分析封装与PCB互连区域差分布线方式,信号布局方式,信号孔/地孔比,布线层与过孔残桩这四个方面对高速差分信号传输性能和串扰的具体影响。利用全波电磁场仿真软件CST建立3D仿真模型,最后时频域仿真验证了所述的优化方法能够有效改善高速差分信号传输性能,减小信号间串扰,实现更好的信号隔离。     

键合线互连电路的优化设计

介绍了一种微波多芯片组件中芯片与传输线互连的键合线互连电路设计。采用低通滤波器方法设计的键合线互连电路结构,在键合线长度一定的情况下,能够显著提高键合线互连电路的频率响应。设计了一种基于3阶低通滤波器的键合线互连电路,将键合线的寄生电感融入了3阶低通滤波器中,改善了键合线互连电路的微波传输特性,提高了键合线互连电路的截止频率。采用微波电路设计软件和三维电磁场软件相结合的设计方法,对键合线互连电路的微波特性进行建模、分析,验证了这种电路设计方法的正确性。     

面向三维集成封装的硅通孔电特性分析

主要针对三维集成封装中的关键技术之一的硅通孔互连技术进行电性能研究。首先简要介绍了硅通孔互连技术的背景,利用三维全波电磁仿真软件建立地．信号一地TSV模型,对其TDR阻抗和时域TDR／TDT信号进行分析,同时仿真分析了TSV互连线及介质基板所使用的材料和TSV半径、高度、绝缘层厚度等物理尺寸对三维封装中TSV信号传输性能的影响。研究结果可为工程设计提供有力的技术参考,有效地用于改善互连网络的S21,提高三维集成电路系统的性能。     

一种新型柱形POP堆叠封装的信号完整性研究

多层Package-on-Package(POP)堆叠封装技术因具有良好的灵活性与扩展性,广泛应用于数字电子产品的制造中.同时,信号在3D集成封装中的速度不断提高,要求封装互连结构具有良好的信号完整性.本文基于一种新型柱形POP封装结构,通过仿真分析工具建立等效模型,分析相邻两层芯片间信号传输过程中噪声干扰对信号的影响以及提高信号质量的方法.对比在不同高度和半径情况下,柱形POP堆叠结构与传统POP堆叠结构上的信号传输质量,证明前者在信号完整性方面的优越性.     

三维封装中的并行键合线信号仿真分析

当今便携式设备的速率可达数吉比特每秒,但是其通道的频宽限制其性能。在所有芯片与基板的传输结构中键合线是最常用的,但却渐渐成为了带宽主要的限制。基于一款高密度布线系统级封装的研发项目,使用全波电磁场仿真工具进行建模分析,研究了不同参数对键合传输线DDR单端信号与差分信号传输质量的影响。最终通过键合线设计的优化,仿真结果通过了眼图的验证。     

三维封装中引线键合技术的实现与可靠性

结合半导体封装的发展,研究了低线弧、叠层键合、引线上芯片、外悬芯片、长距离键合和双面键合6种引线互连封装技术;分析了各种引线键合的技术特点和可靠性.传统的引线键合技术通过不断地改进,成为三维高密度封装中的通用互连技术,新技术的出现随之会产生一些新的可靠性问题;同时,对相应的失效分析技术也提出了更高的要求.多种互连引线键合技术的综合应用,满足了半导体封装的发展需求;可靠性是技术应用后的首要技术问题.     

射频功率晶体管内匹配技术中键合线的建模仿真与参数提取

金属键合线互连是射频大功率晶体管内匹配技术中的关键手段.键合线的直径、长度、拱高和并列键合线间距等物　理参量,均对器件性能有很大影响.采用三维电磁仿真软件EMDS和射频电路设计软件ADS对金属键合线互连进行了建模　仿真和射频等效参数提取,分析了等效参数与键合线各物理参量之间的关系,针对具体的关系特点及内匹配技术中键合线...     

IC封装中互连线信号完整性的研究

随着电子芯片向着高密度、高频率和小体积化方向发展,IC封装的结构尺寸及其互连线系统在信号完整性、损耗等多方面影响着整个电路系统的可靠性。因此,对IC封装及其互连线电特性的分析显得尤为重要。文章以四列直插芯片封装外壳模型为设计实例,利用AnsoftQ3D软件提取了该封装模型的寄生电阻、电容和电感（RCL）,并结合Mult...     

一种基于基片集成波导技术的引线键合结构

当前微波毫米波芯片的引线键合主要是在芯片焊盘和微带线之间实施,当工作频率达到毫米波频段,引线键合的性能对键合线属性及微带线加工精度的敏感度越来越高,键合操作中键合线长度的差异或微带线加工的误差都可能导致键合性能的快速恶化。文章提出了一种基于基片集成波导(SIW)的引线键合结构,该结构直接使用SIW与芯片焊盘或其他电路进行键合,对比现有微带键合方案,使用本文提出的基于SIW的键合方案,可以显著减小加工精度的敏感度,同时减少对介质基片的限制等。文章分别设计了无源和有源SIW键合结构,仿真和测试结果表明:基于SIW的键合结构拥有良好的键合性能,相比微带键合结构,降低了传输损耗、降低了对结构尺寸的灵敏度、改善了键合性能。     

基于信号返回路径宽度的阻抗匹配技术研究

在高速电路设计中,信号源、传输线、负载之间的阻抗是否匹配是决定电路系统中信号完整性优劣的关键因素。针对该问题,从微带线的信号返回路径宽度与传输线特性阻抗之间的关系出发,经研究分析发现:通过改变微带线的信号返回路径宽度,可以有效控制传输线的特性阻抗,从而实现信号源、传输线、负载之间的阻抗匹配,使系统获得较好的信号完整性。同时给出经验公式。并通过实验仿真,其结果表明提出的方法是解决电路系统中阻抗匹配问题的有效途径之一。     

Analytical and Experimental Study on Suppression of Electromagnetic Interference on High Speed Printed Circuit Board for Wireless Communication Systems

In this paper, a novel routing topology is proposed to reduce crosstalk between parallel links used for high data rate application. Generally, microstrip lines are used in high frequency RF printed circuit boards for propagating high speed signals in wireless communication. Since RF front end modules in wireless system supports a wide ultra wide band frequency range from 700 MHz to 12 GHz, package density parasitic effects have been a major issue which degrades system performance. The close proximity of signal transmission lines with a high packing density results signal integrity problems such as crosstalk and timing jitter. A modified coupled microstrip line is proposed to reduce crosstalk by means of increasing capacitive coupling ratio. Our proposed structure reduced far end crosstalk by 4 dB and near end crosstalk by 4 dB than existing structures. The proposed microstrip line increased the maximum data rate from 1 to 3.3 Gb/s and reduced timing jitter by 51 ps at 3.3 Gb/s.     

The impact of a nonideal return path on differential signalintegrity

Printed circuit board transmission lines propagating high-speed digital signals are susceptible to nonideal return paths which may affect signal integrity. In an attempt to clarify this complex issue, this paper presents a study of differential signal integrity issues for the familiar situation in which two coupled microstrip traces are in close proximity to a common reference plane. Differential signaling on coupled microstrip lines and stripline configurations are investigated. Finite-difference time domain simulations are used to demonstrate the impact a nonideal return path can have on differential signal integrity     

Optimal design for a ball grid array wire bonding process using aneuro-genetic approach

This study presents an integrated method in which neural networks, genetic algorithms, and exponential desirability functions are used to optimize the ball grid array (BGA) wire bonding process. As widely anticipated, the BGA package will become the fastest-growing semiconductor package and push integrated circuit (IC) packaging to higher level of compactness and density. However, wire bonding in BGA is difficult owing to its high input/output (I/O) count, fine pitch wire bonds, and long wire lengths. This study addresses two fundamental issues in the semiconductor assembly facility on its quest toward a defect-free manufacturing environment. First, the problem of exploring the nonlinear multivariate relationship between parameters and responses and second, obtaining the optimum operation parameters with respect to each response in which the process should operate. The implementation for the proposed method was carried out in an IC assembly factory in Taiwan; results in this study demonstrate the practicability of the proposed approach     

Circuit model of microstrip patch antenna on ceramic land grid array package for antenna-chip codesign of highly integrated RF transceivers

This paper presents the circuit model of a microstrip patch antenna on a ceramic land grid array (CLGA) package for the antenna-chip codesign of a highly integrated radio-frequency (RF) transceiver. The microstrip patch antenna is fed by packaging interconnect components such as bond wires, signal traces, and vias in a ground-signal-ground (G-S-G) configuration from the carried chip. The circuit model that consists of RLC lumped elements of both microstrip patch antenna and feeding interconnect components has been developed with an emphasis on verifying existing or deriving analytical formulas. The RLC values of the microstrip patch antenna are calculated with our improvements to existing computer-aided design formulas, while the RLC values of the feeding interconnect components are calculated with more efforts. In particular the C values related to the vias and signal traces require to be calculated numerically and they are calculated here with the method of moments and the conformal mapping method, respectively. The circuit model is validated with numerical simulations (High Frequency Structure Simulator) and network analyzer measurements.     

共漏极双功率MOSFET封装研究

针对适用于锂电池保护电路特点要求的共漏极功率MOSFET的封装结构进行了研发和展望.从传统的TSSOP-8发展到替代改进型SOT-26,一直到芯片级尺寸的微型封装外形,其封装效率越来越高,接近100%.同时,在微互连和封装结构的改进方面,逐渐向短引线或焊球无引线、平坦式引脚、超薄型封装和漏极焊盘散热片暴露的方向发展,增...     

绝缘引线在陶瓷封装中的应用

随着半导体封装持续朝着多引脚、小节距及多列多层叠的方向发展,引线键合技术正面临越来越大的挑战。当陶瓷空封器件中的键合引线长度大于3.0 mm时,在加电冲击试验过程中键合引线容易出现瞬间的短路而导致器件失效。文章主要阐述了产生该问题的基本原因,提出了采用绝缘引线键合解决该问题的可行性,介绍了绝缘引线的基本特性,并用实际封装的电路进行了绝缘引线键合的可靠性研究,根据研究结果,提出了绝缘引线可有限应用于陶瓷封装的结论。     

Millimeter-wave components and subsystems built using microstriptechnology

The author describes the evaluation of microstrip as a transmission medium for components and subsystems operating in the millimeter wavebands. The manufacturing process for thin-film MICs on single-crystal quartz is described. The microwave integrated circuit (MIC) manufacturing process is suitable for high-value manufacturing of highly integrated subsystems since manufacturing costs for the circuits are almost independent of the number of circuit functions. Designs for various circuit elements are discussed, and an integrated subsystem is described in which MIC techniques are used to produce a miniature millimeter-wave distance-measuring sensor. Range measurement results for the miniature sensor are presented