Large Flip Chip Assembly Challenges and Risk Mitigation Process

Author(s):  
Jeremy Plunkett ◽  
Suresh Subramaniam ◽  
Nokibul Islam ◽  
Kang KeonTaek ◽  
Gu SeonMo ◽  
...  

Next generation high speed network/communication packages require much larger die sizes and increased ball counts (>3000) to meet high speed, high input/output (I/O) functionality and improved reliability performance. Demand for such high speed large flip chip packages create an opportunity for highly integrated multi-chip modules (MCM’s) and 2.5D/3D silicon (Si) interposer packages which are gradually emerging to meet these requirements. Achieving both increased margins in the power delivery network and increased functionality in next generation high speed network/communication applications requires extremely efficient, low loss package designs with body sizes 50×50mm or larger. One of the biggest challenges for such large die, large body packages is how effectively the assembly risk can be mitigated while fulfilling long term package reliability and functionality. The work presented in this paper describes key factors for mitigating several assembly related issues in the industry, including package warpage/co planarity, and the identification of the optimum processes and materials for successfully manufacturing large body flip chip packages with high assembly yields. As the body sizes and die sizes increase, the chip-to-package interaction failure risk increases significantly due to a larger distance to neutral point (DNP). Typical assembly risks are extreme low-k (ELK) delamination (white bumps) during the chip joining process, bump tearing or cracking, underfill delamination, and warpage issues. A comprehensive experiment was carried out to achieve the objective of the work. A test vehicle was developed using a 21×22mm2, flip chip copper (Cu) column bumped die placed onto a 50×50mm body size, using a multi-layer substrate with full array BGA footprint and ample passive components in the package. Processes were developed to optimize assembly yield and package reliability, including an extensive board level reliability test. Assembly materials were selected to achieve excellent assembly yield, high thermo-mechanical reliability, and increased package functionality.

2010 ◽  
Vol 2010 (DPC) ◽  
pp. 001486-001513
Author(s):  
Jon Aday ◽  
Nozad Karim ◽  
Mike Devita ◽  
Steven Lee

There are 2 primary drivers for advanced substrate technologies to support the next generation of products. One driver is silicon designs which are shifting to 20–40 GBit applications. The band width of these products are requiring advanced materials, and designs which use much thinner cores making routing and manufacturing of these packages easier. The second driver is the move more advanced silicon nodes which also drives the importance for much better power delivery. Coreless substrates enable both of these applications by eliminating the core layer which enables much finner via pitchs to route signals and power/gnd planes. The thinness also reduces the bandwidth used up by the substrate which also enables better electrical performance. This paper will focus on the electrical drivers including simulation to support the structure, flip chip assembly of the package as well as the reliability data associated with the assembly.


2013 ◽  
Vol 2013 (1) ◽  
pp. 000458-000460
Author(s):  
Jonathan Prange ◽  
Julia Woertink ◽  
Yi Qin ◽  
Pedro Lopez Montesinos ◽  
Inho Lee ◽  
...  

Flip-chip interconnect and 3-D packaging applications must utilize reliable lead-free solder joints in order to produce highly efficient, advanced microelectronic devices. The solder alloy most commonly utilized for these applications is SnAg, which is typically deposited by electroplating due to lower cost and greater reliability as compared to other methods. The electroplating performance and robustness of SnAg products for bumping and capping applications is highly dependent on the organic additives used in the process. Here, next-generation SnAg products that improve the rate of solder electrodeposition without compromising key requirements such as tight Ag% control, uniform height distribution and smooth surface morphology will be discussed. These plated solders were then evaluated for compatibility with bumping, capping and micro-capping applications.


1959 ◽  
Vol 63 (585) ◽  
pp. 508-512 ◽  
Author(s):  
K. W. Mangler

When a body moves through air at very high speed at such a height that the air can be considered as a continuum, the distinction between sharp and blunt noses with their attached or detached bow shocks loses its significance, since, in practical cases, the bow wave is always detached and fairly strong. In practice, all bodies behave as blunt shapes with a smaller or larger subsonic region near the nose where the entropy and the corresponding loss of total head change from streamline to streamline due to the curvature of the bow shock. These entropy gradients determine the behaviour of the hypersonic flow fields to a large extent. Even in regions where viscosity effects are small they give rise to gradients of the velocity and shear layers with a lower velocity and a higher entropy near the surface than would occur in their absence. Thus one can expect to gain some relief in the heating problems arising on the surface of the body. On the other hand, one would lose farther downstream on long slender shapes as more and more air of lower entropy is entrained into the boundary layer so that the heat transfer to the surface goes up again. Both these flow regions will be discussed here for the simple case of a body of axial symmetry at zero incidence. Finally, some remarks on the flow field past a lifting body will be made. Recently, a great deal of information on these subjects has appeared in a number of reviewing papers so that little can be added. The numerical results on the subsonic flow regions in Section 2 have not been published before.


Author(s):  
Johan Roenby ◽  
Hassan Aref

The model of body–vortex interactions, where the fluid flow is planar, ideal and unbounded, and the vortex is a point vortex, is studied. The body may have a constant circulation around it. The governing equations for the general case of a freely moving body of arbitrary shape and mass density and an arbitrary number of point vortices are presented. The case of a body and a single vortex is then investigated numerically in detail. In this paper, the body is a homogeneous, elliptical cylinder. For large body–vortex separations, the system behaves much like a vortex pair regardless of body shape. The case of a circle is integrable. As the body is made slightly elliptic, a chaotic region grows from an unstable relative equilibrium of the circle-vortex case. The case of a cylindrical body of any shape moving in fluid otherwise at rest is also integrable. A second transition to chaos arises from the limit between rocking and tumbling motion of the body known in this case. In both instances, the chaos may be detected both in the body motion and in the vortex motion. The effect of increasing body mass at a fixed body shape is to damp the chaos.


Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 593
Author(s):  
Ryota Yanagisawa ◽  
Shunsuke Shigaki ◽  
Kotaro Yasui ◽  
Dai Owaki ◽  
Yasuhiro Sugimoto ◽  
...  

In this study, we fabricated a novel wearable vibration sensor for insects and measured their wing flapping. An analysis of insect wing deformation in relation to changes in the environment plays an important role in understanding the underlying mechanism enabling insects to dynamically interact with their surrounding environment. It is common to use a high-speed camera to measure the wing flapping; however, it is difficult to analyze the feedback mechanism caused by the environmental changes caused by the flapping because this method applies an indirect measurement. Therefore, we propose the fabrication of a novel film sensor that is capable of measuring the changes in the wingbeat frequency of an insect. This novel sensor is composed of flat silver particles admixed with a silicone polymer, which changes the value of the resistor when a bending deformation occurs. As a result of attaching this sensor to the wings of a moth and a dragonfly and measuring the flapping of the wings, we were able to measure the frequency of the flapping with high accuracy. In addition, as a result of simultaneously measuring the relationship between the behavior of a moth during its search for an odor source and its wing flapping, it became clear that the frequency of the flapping changed depending on the frequency of the odor reception. From this result, a wearable film sensor for an insect that can measure the displacement of the body during a particular behavior was fabricated.


Queue ◽  
2021 ◽  
Vol 19 (1) ◽  
pp. 77-93
Author(s):  
Niklas Blum ◽  
Serge Lachapelle ◽  
Harald Alvestrand

In this time of pandemic, the world has turned to Internet-based, RTC (realtime communication) as never before. The number of RTC products has, over the past decade, exploded in large part because of cheaper high-speed network access and more powerful devices, but also because of an open, royalty-free platform called WebRTC. WebRTC is growing from enabling useful experiences to being essential in allowing billions to continue their work and education, and keep vital human contact during a pandemic. The opportunities and impact that lie ahead for WebRTC are intriguing indeed.


Sign in / Sign up

Export Citation Format

Share Document