应用于微系统封装的激光局部加热键合技术

阐述了利用激光与物质相互作用的热效应实现微系统器件的局部加热键合原理 ,提出了激光键合塑料芯片和激光辅助加热阳极键合的思想 ,建立了半导体激光键合实验装置 ,并实现了聚甲基丙烯酸甲酯 (PMMA)之间的键合     

应用于微系统封装的激光局部加热键合技术

阐述了利用激光与物质相互作用的热效应实现微系统器件的局部加热键合原理,提出了激光键合塑料芯片和激光辅助加热阳极键合的思想,建立了半导体激光键合实验装置,并实现了聚甲基丙烯酸甲酯(PMMA)之间的键合.     

微系统感应局部加热封装与键合设计

整体加热封装(即封装过程中整个衬底、芯片、键合层都处于加热状态),不仅工艺时间长,而且高温会对衬底上温度敏感的微结构和电路产生热损坏,或者因为热膨胀系数不匹配导致键合区热应力增大,影响器件可靠性。首先对电磁感应加热实现微系统局部加热封装进行了论述,重点对感应局部加热键合原理、电源选择、感应器和键合层设计,以及键合过程中的温度测试等方面进行了设计分析。对于感应局部加热键合而言,键合区必须设计成封闭环形,其宽度应大于临界尺寸,并且存在一个最佳频率范围。根据键合层材料和结构不同,感应局部加热可用于焊料键合、共晶键合、扩散键合,以实现微系统器件的封装和结构制作。     

MEMS局部加热封装技术与应用

随着半导体技术的发展,封装集成度不断提高,迫切需要发展一种低温封装与键合技术,满足热敏器件封装和热膨胀系数差较大的同质或异质材料间的键合需求。针对现有整体加热封装技术的不足,首先介绍了局部加热封装技术的原理与方法,然后对电流加热、激光加热、微波加热、感应加热和反应加热等几种局部加热封装技术进行了比较分析,最后具体介绍了局部加热封装技术在热敏器件封装、MEMS封装和异质材料集成等方面的应用。由于局部加热封装技术具有效率高、对器件热影响小等优点,有望在MEMS技术、系统封装(SiP)、三维封装及光电集成等领域得到广泛应用。     

面向MEMS封装的微钎料球键合技术

微钎料球键合技术是一种成本低、适应性强,可靠性好的键合技术,容易与现有的IC自动化设备集成。微钎料球键合技术结合倒扣封装可以实现低成本、高密度以及高可靠性的MEMS封装;而且具有自对准或者自组装的功能,在MEMS封装中获得了广泛的应用。准确地预测微钎料球键合对于MEMS自组装的影响依赖于动态模型的发展。微钎料球键合技术的出现推动了标准化的MEMS封装工艺的进程。     

MEMS器件封装的低温玻璃浆料键合工艺研究

玻璃浆料是一种常用于MEMS器件封装的密封材料.系统研究了MEMS器件在低温下使用玻璃浆料键合硅和玻璃的过程.与大多数MEMS器件采用的玻璃浆料相比(烧结温度400℃以上),此工艺(烧结温度350℃)在键合完成后所形成的封装结构同样具有较高的剪切强度(封装器件剪切强度大于360 kPa),同时具有较好的气密性(合格率达到93.3%),漏率测试结果符合相关标准.结果表明,在保证MEMS器件封装剪切强度和气密性的同时,降低键合温度条件是可以实现的.     

基于晶圆键合的MEMS圆片级封装研究综述

为提升微机电系统（MEMS）器件的性能及可靠性,MEMS圆片级封装技术已成为突破MEMS器件实用化瓶颈的关键,其中基于晶圆键合的MEMS圆片级封装由于封装温度低、封装结构及工艺自由度高、封装可靠性强而备受产学界关注。总结了MEMS圆片级封装的主要功能及分类,阐明了基于晶圆键合的MEMS圆片级封装技术的优势。依次对平面互连型和垂直互连型2类基于晶圆键合的MEMS圆片级封装的技术背景、封装策略、技术利弊、特点及局限性展开了综述。通过总结MEMS圆片级封装的现状,展望其未来的发展趋势。     

基于SiP技术的VCSEL阵列微系统封装

针对半实物仿真系统的需求,基于系统级封装技术提出了一款由垂直腔面发射激光器(VCSEL)激光器阵列、激光器驱动芯片、电源芯片等组成的微系统,并介绍了基于微机电系统微纳加工技术的VCSEL激光器阵列的制造工艺流程.该激光器的封装方法具有集成度高、可靠性高等特点,相比于其他驱动及封装方法大大提高了驱动效率和空间利用率,因此在光学成像、通信、互联等领域具有广泛应用前景,为实现半实物仿真中激光成像发生器奠定了基础.     

基于SiP技术的VCSEL阵列微系统封装

针对半实物仿真系统的需求,基于系统级封装技术提出了一款由垂直腔面发射激光器(VCSEL)激光器阵列、激光器驱动芯片、电源芯片等组成的微系统,并介绍了基于微机电系统微纳加工技术的VCSEL激光器阵列的制造工艺流程.该激光器的封装方法具有集成度高、可靠性高等特点,相比于其他驱动及封装方法大大提高了驱动效率和空间利用率,因此在光学成像、通信、互联等领域具有广泛应用前景,为实现半实物仿真中激光成像发生器奠定了基础.     

微机电系统封装技术

首先提出了MEMS封装技术的一些基本要求,包括低应力、高真空、高气密性、高隔离度等,随后简要介绍了MEMS封装技术的分类.在此基础上,综述了三个微机电系统封装的关键技术:微盖封装、圆片级芯片尺寸封装和近气密封装,并介绍了其封装结构和工艺流程.     

A wafer-level microcap array to enable high-yield microsystem packaging

Packaging represents a significant and expensive obstacle in commercializing microsystem technology (MST) devices such as microelectromechanical systems (MEMS), microopticalelectromechanical systems (MOEMS), microsensors, microactuators, and other micromachined devices. This paper describes a novel wafer-level protection method for MSTs which facilitate improved manufacturing throughput and automation in package assembly, wafer-level testing of devices, and enhanced device performance. The method involves the use of a wafer-sized microcap array. This array consists of an assortment of small caps molded onto a material with adjustable shapes and sizes to serve as protective structures against the hostile environments associated with packaging. It may also include modifications which enhance its adhesion to the MST wafer or increase the MST device function. Depending on the application, the micromolded cap can be designed and modified to facilitate additional functions, such as optical, electrical, mechanical, and chemical functions, which are not easily achieved in the device by traditional means. The fabrication and materials selection of the microcap device is discussed in this paper. The results of wafer-level microcap packaging demonstrations are also presented.     

Laser processing for microelectronics packaging applications

The microelectronics industry is moving toward smaller feature sizes. The main driving forces are to improve performance and to lower cost. From the performance point of view the small distances between chips together with the short interconnection routes have of great importance in order to achieve faster operation. Laser processing applied for via generation, direct pattern processing, image transfer, contour cutting, trimming, etc. has proved to be efficient method for making rapid progress in this direction. On the other hand, smaller spaces between conductive patterns increase the risk of short circuits (caused by pattern faults, solder bridges, migration, etc.), that emphasizes the reliability aspects of applied process technologies.The paper describes the results of research projects that aimed at the application of CO₂ and frequency-multiplied Nd:YAG lasers for drilling and direct patterning of copper clad glass fiber reinforced epoxy laminates, polyester foils and a couple of other structures. The physics of processing using five wavelengths, i.e. 10 600, 1064, 532, 355 and 266 nm, were modeled, examined and evaluated. Laser processing was combined with other – mainly metal coating – processes, e.g. the through contacting of the generated vias were carried out by screen printing with polymer thick films, by wet chemical direct plating and by evaporation of thin metal layers, but the details of metallization are not given here.The conclusion summarizes the results and refers to the possibilities of laser processing of metal layers and polymeric materials in microelectronics packaging applications.     

Localized bonding processes for assembly and packaging of polymeric MEMS

Localized bonding schemes for the assembly and packaging of polymer-based microelectromechanical systems (MEMS) devices have been successfully demonstrated. These include three bonding systems of plastics-to-silicon, plastics-to-glass, and plastics-to-plastics combinations based on two bonding processes of localized resistive heating: 1) built-in resistive heaters and 2) reusable resistive heaters. In the prototype demonstrations, aluminum thin films are deposited and patterned as resistive heaters and plastic materials are locally melted and solidified for bonding. A typical contact pressure of 0.4 MPa is applied to assure intimate contact of the two bonding substrates and the localized bonding process is completed within less than 0.25 s of heating. It is estimated that the local temperature at the bonding interface can reach above 150/spl deg/C while the substrate temperature away from the heaters can be controlled to be under 40/spl deg/C during the bonding process. The approach of localized heating for bonding of plastic materials while maintaining low temperature globally enables direct sealing of polymer-based MEMS without dispensing additional adhesives or damaging preexisting, temperature-sensitive substances. Furthermore, water encapsulation by plastics-to-plastics bonding is successfully performed to demonstrate the capability of low temperature processing. As such, this technique can be applied broadly in plastic assembly, packaging, and liquid encapsulation for microsystems, including microfluidic devices.     

Ultrasonic bonding for multi-chip packaging bonded with non-conductive film

System-on-Chip and System-on-Package technologies have advantages depending on application needs. As a number of electrical and electronic equipment manufacturers have an interest in increasing CMOS technology densities, a range of two- and three-dimensional silicon integration technologies are emerging which will support next-generation high-end semiconductors such as high speed microprocessors and high speed memories. However, there are many issues regarding process integration, thermal management, and reliability of 3D stacked package.In this study, the printed circuit board (PCB), silicon carrier and silicon chip are integrated with ultrasonic vibration. Die shear tests of the joints were carried out with increasing bonding time and input power to optimize the bonding condition. The integrated chips were successfully bonded to the PCB with and without NCF using a transverse ultrasonic bonding. Electrical resistance of multi-chip bonded with NCF (10 mΩ) measures lower than that bonded without NCF (28.9 mΩ). The voids and delamination were easily found on the joint bonded without NCF that caused lower shear strength.     

用于MEMS器件芯片级封装的金-硅键合技术研究

MEMS器件大都含有可动的硅结构 ,在器件加工过程中 ,特别是在封装过程中极易受损 ,大大影响器件的成品率。如果能在MEMS器件可动结构完成以后 ,加上一层封盖保护 ,可以显著提高器件的成品率和可靠性。本文提出了一种用于MEMS芯片封盖保护的金 硅键合新结构 ,实验证明此方法简单实用 ,效果良好。该技术与器件制造工艺兼容 ,键合温度低 ,有足够的键合强度 ,不损坏器件结构 ,实现了MEMS器件的芯片级封装。我们已经将此技术成功地应用于射流陀螺的制造工艺中     

用于MEMS器件芯片级封装的金-硅键合技术研究

MEMS器件大都含有可动的硅结构，在器件加工过程中，特别是在封装过程中极易受损，大大影响器件的成品率。如果能在MEMS器件可动结构完成以后，加上一层封盖保护，可以显著提高器件的成品率和可靠性。本文提出了一种用于MEMS芯片封盖保护的金-硅键合新结构，实验证明此方法简单实用，效果良好。该技术与器件制造工艺兼容，键合温度低，有足够的键合强度，不损坏器件结构，实现了MEMS器件的芯片级封装。我们已经将此技术成功地应用于射流陀螺的制造工艺中。     

塑料生物芯片的激光焊接封装系统研究

介绍了采用半导体激光器在塑料生物芯片焊接封装系统的应用，论述了塑料生物芯片焊接封装原理和工艺，提出了基于808nm半导体激光器的塑料焊接封装系统的设计方法，分析了焊接封装的参数选择，实现了部分塑料之间的成功焊接。     

塑料生物芯片的激光焊接封装系统研究

介绍了采用半导体激光器在塑料生物芯片焊接封装系统的应用 ,论述了塑料生物芯片焊接封装原理和工艺 ,提出了基于 80 8nm半导体激光器的塑料焊接封装系统的设计方法 ,分析了焊接封装的参数选择 ,实现了部分塑料之间的成功焊接     

MEMS post-packaging by localized heating and bonding

This work addresses important post-packaging issues for microsystems and recommends specific research directions by localized heating and bonding. Micropackaging has become a major subject for both scientific research and industrial applications in the emerging field of microelectromechanical systems (MEMS). Establishing a versatile post-packaging process not only advances the field but also speeds up the product commercialization cycle. A review of engineering bases describing current technologies of MEMS packaging and wafer bonding is followed by an innovative post-packaging approach by localized heating and bonding, process demonstrations by selective encapsulation are presented, including an integrated low pressure chemical vapor deposition (LPCVD) sealing process, localized silicon-gold eutectic bonding, localized silicon-glass fusion bonding, localized solder bonding and localized CVD bonding processes.