基于LTCC技术的垂直互连微波传输特性研究

发布时间：2018-01-06 10:43

本文关键词：基于LTCC技术的垂直互连微波传输特性研究　出处：《西安电子科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着通信产业的快速发展,各种智能化、小型化的终端产品不断涌现,智能手机、平板电脑等电子产品正在改善着人们的生活。人们对电子产品要求的不断提高,直接推动了微电子产业不断向前发展,集成电路封装技术也处在不断革新之中。其中,低温共烧陶瓷技术以其优异的高频性能、极高的集成度、较低的成本在蓝牙、WLAN等领域取得了广泛的应用。在该工艺中,常使用垂直通孔连接不同介质基板上的走线,通孔的传输特性直接影响到了信号的传输质量,因此必须对通孔传输特性的影响因素进行充分研究。本文主要对LTCC中的垂直互连结构进行了系统的研究,建立了垂直通孔的等效电路模型,采用准静态分析法并运用高斯定理等推导出通孔寄生参数的计算公式,将推导出来的公式输入到MATLAB软件中进行数值计算并与Q3D软件的计算结果进行对比,结果显示公式的计算结果与仿真结果的误差不超过10%。接着,将等效电路模型在ADS中进行了S参数仿真并与通孔的HFSS仿真结果相对照,结果表明文中的等效电路模型在低频和偏离谐振的频点上具有较高的准确性。使用HFSS软件建立了通孔的三维电磁仿真模型,分析了通孔尺寸(包括通孔半径、焊盘半径、反焊盘半径和通孔长度)、传输线的连接角以及屏蔽孔的存在对垂直互连结构微波传输特性的影响。仿真结果表明,通过改变通孔的尺寸可以实现对其传输特性的微调,越是接近180°的夹角传输特性就越好,屏蔽孔的存在能对互连结构的第一谐振频率起到很大的调节作用,并且能够使得S参数曲线走势更加平滑,在一定程度上增大了互连结构的带宽。论文还研究了互连结构的谐振频率在改善传输线微波传输特性上的特殊作用。基于阻抗匹配技术,在ADS中对垂直互连结构进行阻抗匹配设计,将设计好的传输线结构在HFSS中建立模型并仿真优化。文中分别对工作频率为20GHz和50GHz的互连结构进行阻抗匹配,匹配后的结果表明,并联单枝节匹配以及四分之一波长变换器都可以有效改善通孔在工作频率周围的微波传输特性,且四分之一波长变换器匹配具有更小的面积和更宽的带宽。另外,受阻抗匹配设计思想的启发,文中还采用了椭圆形反焊盘和阻抗调节段的方式对电路阻抗进行微调,使得通孔的微波传输特性得到了一定程度的改善。
[Abstract]:With the rapid development of the communication industry, a variety of intelligent, miniaturized end products continue to emerge, smart phones. Electronic products, such as tablets, are improving people's lives. The increasing demand for electronic products has directly promoted the development of microelectronics industry. Integrated circuit packaging technology is also in constant innovation. Among them, low temperature co-fired ceramic technology with its excellent high frequency performance, high integration, low cost in Bluetooth. WLAN and other fields have been widely used. In this process, vertical through holes are often used to connect the lines on different dielectric substrates, and the transmission characteristics of through holes directly affect the quality of signal transmission. Therefore, it is necessary to study the influence factors of through hole transmission characteristics. In this paper, the vertical interconnect structure in LTCC is studied systematically, and the equivalent circuit model of vertical through hole is established. By using quasi-static analysis method and Gao Si theorem, the formulas for calculating parasitic parameters of through holes are derived. The derived formula is inputted into MATLAB software for numerical calculation and compared with the results of Q3D software. The results show that the error between the calculation results and the simulation results is not more than 10. Then, the equivalent circuit model is simulated in ADS and compared with the through hole HFSS simulation results. The results show that the equivalent circuit model in this paper has high accuracy in low frequency and deviation from resonance frequency. A 3D electromagnetic simulation model of through hole is established by using HFSS software. The size of through hole (including through radius, pad radius, reverse pad radius and through hole length) is analyzed. The influence of the connection angle of transmission line and the existence of shielding hole on the microwave transmission characteristics of vertical interconnection structure. The simulation results show that the transmission characteristics can be fine-tuned by changing the size of the through hole. The closer to 180 掳angle transmission characteristics, the better, the existence of shielding holes can play a great role in regulating the first resonant frequency of the interconnection structure, and can make the S parameter curve more smooth. To a certain extent, the bandwidth of the interconnection structure is increased. The special role of resonant frequency of the interconnection structure in improving the microwave transmission characteristics of transmission lines is also studied, based on impedance matching technology. The impedance matching design of vertical interconnection structure is carried out in ADS. The designed transmission line structure is modeled in HFSS and optimized by simulation. The impedance matching of 20 GHz and 50 GHz interconnect structures is carried out respectively, and the matching results show that. Parallel single-branch matching and 1/4 wavelength converter can effectively improve the microwave transmission characteristics around the working frequency. The matching of 1/4 wavelength converter has smaller area and wider bandwidth. In addition, it is inspired by the design idea of impedance matching. In this paper, the impedance of the circuit is fine-tuned by using the elliptical reverse pad and the impedance adjusting section, which improves the microwave transmission characteristics of the through hole to a certain extent.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN015;TN405

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