分立IGBT的封装技术研究

文章通过对单器件的分立IGBT的封装结构进行分析,针对其结构特点和封装技术要求,特别是封装关键工艺芯片切割的影响,对装片、焊接方面进行工艺研究。并通过试验分析解决实际生产所出现的技术问题,由此形成一套适应于大批量封装生产的IGBT封装工艺技术,成功地应用于分立IGBT器件的批量生产,保证了产品的可靠性,取得了很好的生产效益。     

铅锡烧结全自动装片设备与工艺的研究

本文通过对KNS6300全自动装片机铅锡烧结设备与工艺调试的探索，得到了铅锡烧结全自动装片寻找工艺最佳点的方法，提出了铅锡烧结全自动装片工艺与设备中共性问题的解决设想方案。     

GZP-2全自动硅片装片机的研制

太阳能电池制造过程中,有多个工序需将硅片装入篮具中,目前的人工装片方式碎片率高、对硅片的污染多.装片机可以代替人工装片,克服人工装片的缺点.主要介绍了GZP-2全自动硅片装片机研制过程中所涉及的机械结构,电气控制等方面的技术,对整机的工作原理、特性和技术创新等做了详细的叙述.     

GZP-2全自动硅片装片机的研制

太阳能电池制造过程中,有多个工序需将硅片装入篮具中,目前的人工装片方式碎片率高.对硅片的污染多.装片机可以代替人工装片,克服人工装片的缺点.主要介绍了GZP-2全自动硅片装片机研制过程中所涉及的机械结构,电气控制等方面的技术,对整机的工作原理、特性和技术创新等做了详细的叙述.     

封装过程中装片后烘烤机理及改善方法探讨

本文探讨并验证了IC封装工序装片后烘烤过程的机理,结合烘烤后失重曲线的分析,重新设计了烘烤升温曲线（烘烤固化）、氮气保护（防止铜材氧化）、抽风（排出挥发物）等工艺参数。验证结果表明,重新设计后的烘烤过程,克服了装片胶挥发污染、铜材氧化这两个对产品可靠性影响最关键的不利因素,降低了装片烘烤工艺对产品可靠性的影响。     

车载IGBT器件封装装片工艺中空洞的失效研究

IGBT芯片在TO-220封装装片时容易形成空洞,焊料层中空洞大小直接影响车载IGBT器件的热阻与散热性能,而这些性能的好坏将直接影响器件的可靠性。文章分析了IGBT器件在TO-220封装装片时所产生的空洞的形成机制,并就IGBT器件TO-220封装模型利用FEA方法建立其热学模型,模拟结果表明:在装片焊料层中空洞含量增加时,热阻会急剧增大而降低IGBT器件的散热性能,IGBT器件温度在单个空洞体积为10%时比没有空洞时高出28.6℃。同时借助工程样品失效分析结果,研究TO-220封装的IGBT器件在经过功率循环后空洞对于IGBT器件性能的影响,最后确立空洞体积单个小于2%,总数小于5%的装片工艺标准。     

60 mm尺度CMOS图像传感器装片工艺技术研究

为了在使用过程中得到高质量的图像,对CMOS图像传感器芯片的贴装精度、芯片倾斜度及装片胶的稳定性要严格控制.对一款60 mm尺度CMOS图像传感器芯片封装结构进行优化研究,进一步优化装片材料和装片工艺参数,解决了芯片倾斜和翘曲问题.芯片翘曲度在10 μm以内,满足图像传感器对封装的技术要求以及可靠性要求.     

全自动硅片装片机工艺设备研制

太阳能电池制造过程中,有多个工序需将硅片装入篮具中,目前的人工装片方式碎片率高、对硅片的污染多、劳动强度大.全自动硅片装片机可以代替人工装片,克服人工装片的缺点.本文主要介绍了全自动硅片装片机的关键技术,并对整机的工作原理、特性和技术创新等做了详细的叙述.     

超高频晶体管共晶装片中eb结失效的分析

我厂超高频低噪声晶体管在管芯生产过程中，应用了许多特殊工艺，如预光刻、浓棚扩散、硼离子注入、浅结扩散、引线孔光刻采用泡发射极工艺，背面六层金属电极工艺，延伸电极钛铝合金等工艺。3DG79（即3DG105，是正向自动增益控制超高频、低噪声晶体管）用于VHF高频调谐器高频放大用。起先我们是用银浆装片的，为了提高组装质量的一致性，减少集电极欧姆接触电阻，最近我们把3DG79的装片工艺也改成自动共晶装片。共晶装片是在410℃温度情况下，管芯背面（V，N1，AuGe，AuCeSb，AuGe，Au）六层电极的金属层在振动头振动磨擦作用下，…     

SOT23系列产品MSL1封装工艺研究

近年来集成电路封装材料、设备及工艺技术研究进展迅速,尤其是封装材料及封装设备更是日趋完善。材料性能和设备能力已不再是SOT23系列产品达到MSL1要求的主要/关键限制因素。文章主要研究影响SOT23系列产品达到MSL1要求的工艺过程因素,寻求SOT23系列产品达到MSL1要求的工艺过程控制解决方案。通过对工艺过程中关键工序加工方法、工艺流程及工艺条件的试验,最终确定了可以稳定通过MSL1的方案,其主要做法是:在粘片后采用分段烘烤,在压焊和塑封前加等离子清洗以及对工序间间隔时间进行控制。     

Cooling rate in diode laser bonding

Diode laser die bonding parameters were measured for the cases of slow cool and rapid cool die bonding processes. The thermal strain, solder composition and structure, thermal impedance, and bond strength of InP based diode lasers bonded to AlN chip carriers using pre-deposited Au-Sn solder were examined. Relative to the rapid cool process, the slow cool process was found on average: to induce greater strain in the laser chips; to exhibit a larger thermal impedance in the die bonds; to produce a rougher solder structure; and, to promote alloying of the solder material and chip carrier metallization.     

IGBT芯片参数对瞬态均流特性的影响

IGBT模块一般采用多芯片并联的方式进行封装,但由于模块参数、驱动控制等差异,模块内部存在电流分布不均衡的问题。相比于稳态电流分布,瞬态电流分布的影响因素众多,是研究的热点。针对IGBT的芯片参数开展了模块内部各支路瞬态电流分布特性的研究。通过建立IGBT芯片模型及芯片并联的瞬态电路分析模型,计算单一芯片参数与多种芯片参数作用下IGBT模块的瞬态电流分布,提出新的适用于芯片支路瞬态均流分析的评价指标,得到了IGBT芯片参数对并联瞬态均流影响的规律。研究结果表明阈值电压、跨导和栅极电阻是对瞬态均流影响最大的3个芯片参数,且需要关注阈值电压与跨导的共同影响。研究结果对IGBT的芯片筛选及并联后的瞬态均流计算具有指导意义。     

Reverse‐Conducting IGBT Using MEMS Technology on the Wafer Back Side

In this paper, we present a 600‐V reverse conducting insulated gate bipolar transistor (RC‐IGBT) for soft and hard switching applications, such as general purpose inverters. The newly developed RC‐IGBT uses the deep reactive‐ion etching trench technology without the thin wafer process technology. Therefore, a freewheeling diode (FWD) is monolithically integrated in an IGBT chip. The proposed RC‐IGBT operates as an IGBT in forward conducting mode and as an FWD in reverse conducting mode. Also, to avoid the destructive failure of the gate oxide under the surge current and abnormal conditions, a protective Zener diode is successfully integrated in the gate electrode without compromising the operation performance of the IGBT.     

多层芯片应用中的封装挑战和解决方案

The continuous growth of stacked die packages is resulting from the technology‘s ability to effectively increase the functionality and capacity of electronic devices within the same footprint as a single chip.The increased utilization of stacked die packages in cell phone and other consumer products drives technologies that enable multiple die stacks within a given package dimension.This paper reviews t6he technology requirements and challenges for stacked die packages.Foremost among these is meeting package height is 1.2mm for a single die package.For stacked die packages,two or more die need to fit in the same area.That means every dimension in the package has to decrease,including the die thickness.the mold cap thickness,the bond line thickness and the wire bond loop profile.The technology enablers for stacked die packages include wafer thinning,thin die attachment,low profile wire bonding,bonding to unsupported edges and low sweep molding.     

IGBT焊料层中的空洞对器件热可靠性的影响

根据IGBT的基本结构和工作原理,建立了一种新的IGBT三维热模型。该模型考虑了Si材料的温度特性,模拟研究了焊料层空洞对器件热稳定性的影响。研究表明焊料层空洞对IGBT器件的热稳定性有很大的影响。实测结果、超声波显微镜以及红外显微镜的扫描图片证实模拟结果。该研究结果对于改进IGBT器件的可靠性有一定意义,值得器件应用工程师、设计及工艺工程师参考。     

基于IGBT模块饱和压降温度特性的结温探测研究

实验室条件下,IGBT模块的结温探测是瞬态热阻抗测试的关键。首先分别在热稳态和热瞬态下证明了饱和压降温度特性只与芯片有关,然后建立了IGBT模块结温探测模型,利用饱和压降值和集电极电流值来计算结温值,并将用模型计算出的结温与光纤实测的结温相比较,吻合性良好,证明了模型计算法能够准确探测结温。该方法可以用于恒流加热过程中瞬态热阻抗的测量,比起热敏参数法中冷却过程测量瞬态热阻抗相比,更具有实际意义。     

IGBT模块焊料层空洞对模块温度影响的研究

介绍了IGBT模块的封装工艺,分析真空回流焊接过程中焊料层空洞的形成机理,并使用SAM方法检测并测量空洞;接着通过有限元模拟方法对模块进行热分析,对比了焊料层有、无空洞情况下模块的整体温度,具体研究焊料层空洞尺寸、空洞分布位置和焊料层厚度对芯片温度分布的影响。     

Enhanced power cycling performance of IGBT modules with a reinforced emitter contact

A typical emitter contact of an IGBT consists of a front metallization and bond wires. In this study, the power cycling performance of a special emitter contact design is experimentally verified. The emitter contact includes a metal plate, which is Ag-sintered to the metallization and wire bonded on the top surface. Either Cu or Al bond wires were implemented. Power cycling tests were performed to investigate the performance of such IGBT modules. The results were very promising and a cycling lifetime was achieved, which is about 20 times higher than the lifetime of typical IGBT modules. For a better understanding of the experimental results, the electrical and thermal response of the IGBT modules were simulated by FEM. The results of this study, provide a key for high-reliability designs of the emitter contact of IGBT modules with superior power cycling capability.     

Reliability and lifetime evaluation of different wire bonding technologies for high power IGBT modules

IGBT modules for power transmission, industrial and traction applications are operated under severe working conditions and in harsh environments. Therefore, a consequent design, focused on quality, performance and reliability is essential in order to satisfy the high customer requirements. One of the main failure mechanisms encountered in high power IGBT modules subjected to thermal cycles is wire bond lift-off, which is due to the large thermal expansion coefficient mismatch between the aluminum wires and the silicon chips. The paper describes various bonding technologies using different wire materials directly bonded onto chip metallisation as well as the ABB solution where the wire is bonded on a thin molybdenum strain buffer soldered onto the chip. We assess in the present paper the potential of these technologies to enhance module reliability and lifetime through a power cycling test. Failure analysis results are presented and the failure mechanisms related to each technology are explained in detail.