Wafer-level Cu–Cu bonding technology

Semiconductor industry currently utilizes copper wafer bonding as one of key technologies for 3D integration. This review paper describes both science and technology of copper wafer bonding with regard to present applications. The classification of Cu bonding, bonding mechanisms, process developments, its microstructure evolution, as well as other characterizations are reviewed. Researches about patterned Cu bonding, future prospects, and 3D integration using Cu bonding are discussed in this paper.     

Cu溶解溶液

本文概述了Cu 和 Cu 合金用的溶解溶液,适用于Cu 和 Cu 合金的蚀刻和化学研磨等工艺,特别适用于制造微细图形的高密度印制板。     

Sn-3.0Ag-0.5Cu/Cu焊点可靠性研究

采用铺展面积法研究了Sn-3.0Ag-0.5Cu无铅钎料在不同温度下的润湿性能,同时探讨了150℃等温时效对Sn-3.0Ag-0.5Cu/Cu焊点界面组织及力学性能的影响。结果表明,随着钎焊温度的升高,Sn-3.0Ag-0.5Cu钎料的润湿性能明显增加。焊后钎料/Cu界面处对应的金属间化合物为Cu6Sn5相,经150℃时效,界面层的形貌由原来的齿状逐渐转化为层状,且厚度随着时效时间的增加而增加。发现界面层金属间化合物厚度与时效时间的二次方根成线性关系。对焊点在时效过程中的力学性能进行分析,发现Sn3.0Ag0.5Cu/Cu焊点的力学性能随着时效时间的增加逐渐降低,时效初期,焊点的力学性能下降较快,后期趋于平缓。     

Cu箔表面处理工艺

概述了PCB用Cu箔光泽面的表面处理工艺。处理过的Cu箔与树脂粒子难以融着到Cu箔光泽面上,而且具有优良的耐热变色性、焊料湿润性,抗蚀剂附着性和防锈蚀性等性能。     

Cu接口标准化介绍

本文首先对Cu接口的标准化情况进行了介绍,然后对Cu接口的技术要求包括Cu接口的物理、电气、逻辑特性和USIM应用的内容进行了介绍。     

Cu导体陶瓷基板

<正> 日本三菱电机生产技术研究所最近开发成Cu导体陶瓷基板,采用该基板制成大功率组件的寿命比原用基板提高10倍以上。由于它是将氧化钼箔夹在钢导体之间制成的,散热性能     

Cu—Invar—Cu印制板在功率SMT电路中的应用

本文介绍了Ｃｕ－Ｉｎｖａｒ－Ｃｕ（铜烟瓦）印制板的特点，及其在ＳＭＴ电路中的应用．     

Cu/Sn/Cu界面元素的扩散行为研究现状

从老化过程的界面作用和Cu/Sn/Cu界面元素扩散行为等方面,综述了国内外研究动态与进展。随后,着重介绍了老化过程Sn基钎料和Cu基板的界面反应和柯肯达尔孔洞形成的影响因素,并且柯肯达尔孔洞的形成与界面组分元素的扩散直接相关。最后指出了Cu/Sn/Cu焊点扩散行为研究中存在的问题,提出采用实验与分子动力学模拟相结合的方法开展研究,为以后界面元素扩散的研究起到启发作用。     

Cu/Nb微观复合线材中Cu沿径向的织构研究

本文利用电子背散射衍射(EBSD)技术,对含不同铌芯丝数的Cu/Nb微观复合线材中的Cu沿径向的织构进行了表征.结果表明:复合线材在拉拔过程中,各层织构存在差异,织构种类由表及里减少,且主要向平行于拉拔方向的〈111〉丝织构聚集;对于复合不同道次的样品,在相同部位,变形量大的线材内部织构更集中于〈111〉织构组分.     

Cu—Cu键合工艺及其在高功率声光器件中的应用

介绍了一种低温Cu—Cu扩散键合工艺技术,利用电子束蒸发Cr/Cu薄膜作为键合层制作了声光调制器。实验表明,Cr/Cu/Cu/Cr键合层厚为755.5 nm、键合温度120℃、键合压强30 MPa时,器件键合强度可达2.7 MPa。采用该工艺制作的调制器能够承受的最大电功率为8 W/mm~2,且峰值衍射效率达到70%,为研制高功率声光器件奠定了工艺基础。     

化学镀Cu—Ni合金

概述了PH=5—10的化学镀Cu—Ni合金工艺,用以取代传统的以HCHO为还原剂的强碱性化学镀Cu工艺,特别适用于刚性印制板,挠性印制板磁带自动粘结等电子部品的制造。     

时效对Sn3.0Cu0.15Ni/Cu界面组织的影响

研究了150℃时效0,200,500h对Sn3.0Cu0.15Ni/Cu界面组织结构的影响.结果表明:界面金属间化合物层由Cu6Sn5层和Cu3Sn层组成,质量分数为0.15％的Ni的加入会使IMC层最初变厚,但在时效过程中,热稳定性强的界面化合物(Cu,Ni)6Sn5的生成,会抑制Cu3Sn化合物层的生长;同时Ni的加入会降低Cu6Sn5颗粒的长大速度,并且随着时效时间的延长,Cu6Sn5颗粒的形貌呈多面体结构.     

Cu/Nb微观复合线材中Cu沿径向的织构研究

本文利用电子背散射衍射(EBSD)技术,对含不同铌芯丝数的Cu/Nb微观复合线材中的Cu沿径向的织构进行了表征。结果表明:复合线材在拉拔过程中,各层织构存在差异,织构种类由表及里减少,且主要向平行于拉拔方向的<111>丝织构聚集;对于复合不同道次的样品,在相同部位,变形量大的线材内部织构更集中于<111>织构组分。     

Low cycle fatigue performance of ball grid array structure Cu/Sn–3.0Ag–0.5Cu/Cu solder joints

Low cycle fatigue performance of ball grid array (BGA) structure Cu/Sn–3.0Ag–0.5Cu/Cu joints with different standoff heights (h, varying from 100 to 500 μm) and two pad diameters (d, d = 320 and 480 μm) under displacement-controlled cyclic loading was studied by experimental method and finite element (FE) simulation. A prediction method based on the plastic strain energy density and continuum damage mechanics (CDM) framework was proposed to evaluate the initiation and propagation of fatigue crack in solder joints. The results show that fatigue failure of solder joints is a process of damage accumulation and the plastic strain energy density performs a power function correlation with the cycle numbers of crack initiation and propagation. Crack propagation rate is affected by the stress triaxiality, which is dependent on the loading mode and increases dramatically with decreasing h under tensile loading, while the change of standoff height has very limited influence on the stress triaxiality under shear loading mode. Moreover, crack growth correlation constants identified in Cu/Sn–3.0Ag–0.5Cu/Cu joints with a specific geometry (h = 100 μm and d = 480 μm) can be well used to predict the fatigue life of BGA joints with other geometries. Furthermore, the results have also shown that the fatigue life of solder joints increases with decreasing the geometric ratio of h/d under the same nominal shear strain amplitude, while it drops with decreasing h/d under the same shear displacement amplitude in cyclic loading. When the geometric ratio (i.e., h/d ratio) is unchanged, the miniaturization of BGA joints brings about a decrease in fatigue life of the joints.     

化学镀Cu—Ni合金工艺

概述了ＰＨ５－１０的化学镀Ｃｕ－Ｎｉ合金工艺。特别适用于制造刚性印制板（ＲＰＣ）、挠性印制板（ＦＰＣ）和磁带自动粘结带（ＴＡＢ）等电子部品。     

A fast test technique for life time estimation of ultrasonically welded Cu–Cu interconnects

In this research the quality of the interconnects of the ultrasonically welded Cu terminals to the Cu substrate in the IGBT-module has been investigated. An ultrasonic resonance fatigue system in combination with a laser Doppler vibrometer and a special specimen design was used for shear fatigue testing of these large ultrasonic Cu–Cu welds (about 0.5 cm²). Fatigue life curves up to 10⁹ loading cycles were obtained in a very short period of time. Using this technique it was possible to evaluate the fatigue strength of these interconnects for the first time. The microstructural features of the interconnects were characterized and their crack growth behaviour was studied. Fracture analysis of the fatigued specimen shows that failure occur due to the propagation of the crack beneath the welding interface into the copper substrate. Additionally performed finite element simulations offer an insight into the stress and strain concentrations during the mechanical fatigue tests. As this method is not restricted to the welding geometry, material joints with larger interconnects can be tested likewise. Thus this new technique can be used as a practical and valid fatigue testing method for evaluation of various interconnects.     

Cu材料激光表面强化研究

采用激光技术对Cu基材进行表面强化处理。使用扫描电镜(SEM)、电子能谱计(EDS)和X射线衍射仪(XRD)对强化表面进行显微组织和物相分析,并测试了样品的显微硬度、耐磨性能和导电性能。结果表明,激光强化层无裂纹,组织细小均匀、呈快速凝固特征,强化层具有较高的硬度(平均硬度为625HV0.1)和良好的耐磨性,其磨损失重仅为纯Cu基材的1/5,而激光表面强化使导电性略微降低。激光表面强化层硬度和耐磨性的提高可归因于颗粒强化、细晶强化和固溶强化的共同作用,而导电性的降低程度主要受稀释率的影响。     

磁控溅射生长Cu/Si薄膜

用溅射方法在Si(111)上生长Cu/Si,Ti/Si,Cu/Ti/Si薄膜。用XRD,红外吸收光谱,台阶仪对薄膜进行分析和测量。结果表明:在150℃溅射生长出的Cu/Ti/Si薄膜的缓冲层为硅化物TiSi2(311);Cu薄膜的主要成分是晶粒大小为17nm的Cu(111);Cu/Ti/Si(111)平均厚度为462nm,粗糙度为薄膜厚度的3%。在以TiSi2薄膜为缓冲层的Si(111)衬底上生长出的Cu薄膜抗氧化性较强、薄膜均匀性和致密性较好。