【作者】 姬五胜；

【导师】 李英；

【作者基本信息】 上海大学 ， 无线电物理， 2004， 博士

【摘要】 近半个世纪以来，微波电路发展十分迅速，它经历了从低频到高频、从单层到多层的发展历程，最终导致了微波多芯片组件的产生。随着多芯片组件密度的不断提高，互连的不连续性成为制约整体性能的瓶颈。因此，对互连进行仿真和建模，对于微波多芯片组件的设计有着重要的意义。本论文以垂直通孔互连作为研究对象，对通孔的散射参数进行了数值仿真和软件仿真，得到了一些有益的结论。主要的研究工作如下： 首先，以分段正弦函数作为基函数，采用矩阵束矩量法(Matrix-penciled Momem Method)分析了多层封装环境下微带线-通孔-微带线互连模型，得到了通孔的散射参数，并总结了该互连结构通孔的散射参数在其几何尺寸变化时所表现出来的规律。并以B-样条函数作为基函数进行了分析，对比了以分段正弦函数作为基函数的结果，结果表明，分段正弦函数作为求解垂直通孔互连问题的矩阵束矩量法的基函数，从精度和计算量两个方面来说都是可行的。 其次，以微带线—通孔—微带线互连结构作为研究对象，针对微带线连接角是任意角度的情况，利用Ansoft Ensemble 7.0仿真软件，对此时通孔的散射特性和辐射功率进行了仿真，得到了散射特性和辐射功率随微带线连接角的变化规律。 第三，以低温共烧陶瓷微波多芯片组件中微带线—通孔—带状线互连模型作为仿真对象，在信号通孔周围等距离对称地加上同轴屏蔽通孔，仿真了信号通孔的散射参数，结果表明屏蔽通孔能够改善信号通孔的散射特性。保持微带线—通孔—带状线互连结构不变，在微带线和带状线之间加入一层介质，并考虑了存在同轴屏蔽通孔的情况，仿真结果表明加入介质层能明显改善信号通孔的散射特性，此时若再加上屏蔽通孔，散射特性会变差。 第四，以共面线-共面线倒装互连结构作为研究对象，采用时域有限差分法分析了此倒装结构中焊盘的散射特性。数值结果表明，焊盘的高度或宽度越小，焊盘的散射特性越好。焊盘的自感是其不连续性的主要因素，且自感与焊盘的高度是成比例增大的。当上、下层共面线相互交迭部分的长度变短时，当芯片、主板以及上、下共面线之间这三个区域介质的介电常数变小时，在这两种情况下，焊盘的散射特性均得到改善。 最后，对比了矩阵束矩量法和时域有限差分法的优缺点。对于垂直通孔互连问题，时域有限差分法更具优势。垂直通孔互连是微波多芯片组件封装工艺和理论分析的基础，开展垂直通孔互连的研究有着现实的意义。更多还原

【Abstract】 During the last half century, it is rapidly developing of microwave circuit technique either from low frequency to high frequency or from single layer to multiple layers that leads to the coming of microwave multi-chip module (MMCM). With the increasing density of multi-chip module, the discontinuity of interconnect is the choke point which restrains its integral performance. Hence, it is significant for the design of MMCM to simulate and model of interconnect. The work in this dissertation is, focused on the problem of vertical via interconnect, to fulfil numerical and software simulation on via’s scattering parameter. Some useful results are obtained. Main study contains the following:Firstly, Matrix-penciled moment method with piecewise sinusoidal basis function is used to analysis and compute via’s scattering parameter of microstrip-via-microstrip interconnect model of multi-layered environment. Some laws of scattering parameter in the interconnect structure are shown while to change via’s geometric parameters. Another analysis is made by considering B-spline function as the basis function to carry the same process. By contrast, the former is feasible to solve the vertical via interconnect problem for the acceptable precision and the cost of implement.Secondly, considering microstrip-via-microstrip interconnect structure, for the case that microstrip connecting angle is arbitrary, simulation is programmed in Ansoft Ensemble 7.0 simulation software so as to obtain scattering parameter and radiation power. The inherent relationship between changes of scattering parameter and radiation power is explored and reported when microstrip connecting angle changes.Thirdly, the object to simulate is microstrip-via-microstrip interconnect model of MMCM in LTCC, equal-distance and symmetric adding coaxially shielding via around signal via. With the simulation of signal via’s scattering parameter, conclusion that shielding via can improve the scattering parameter of signal via. Considering that there exists synchronously coaxially shielding via, simulating result shows that to add a layer of dielectric between microstrip and stripline can improve evidently the scattering parameter of signal via. But if adding progressively shielding via, its scattering parameter will become worse.Fourthly, the object to study is CPW-CPW flip-chip interconnect structure. Scattering parameter of solder bump in flip-chip structure is analyzed by using FDTD. It is shown from result of numerical experiment that the less the bump’s height and width are, the better of its scattering parameter. It is also come out that the bump’s inductance which is proportioned to its length is the major factor to cause discontinuity. Both the case that the overlap part’s length between upper and lower layer CPW becomes short, and the case that dielectric constant of the chip, mother board, and media between the chip and mother board becomes small, the bump’s scattering parameter can be improved.Lastly, the advantage and disadvantage of two methods, namely matrix-penciled moment method and FDTD method, is presented by contrast. FDTD method is better than the other one for vertical via interconnect problem. Because vertical via interconnect is the base of theoretical analysis and package technics of MMCM, further study on vertical via interconnect is very vital and instructive to reality.更多还原