Technical Library | 2023-01-17 17:58:36.0
Heterogeneous integration has become an important performance enabler as high-performance computing (HPC) demands continue to rise. The focus to enable heterogeneous integration scaling is to push interconnect density limit with increased bandwidth and improved power efficiency. Many different advanced packaging architectures have been deployed to increase I/O wire / area density for higher data bandwidth requirements, and to enable more effective die disaggregation. Embedded Multi-die Interconnect Bridge (EMIB) technology is an advanced, cost-effective approach to in-package high density interconnect of heterogeneous chips, providing high density I/O, and controlled electrical interconnect paths between multiple dice in a package. In emerging architectures, it is required to scale down the EMIB die bump pitch in order to further increase the die-to-die (D2D) communication bandwidth. Aa a result, bump pitch scaling poses significant challenges in the plated solder bump reflow process, e.g., bump height / coplanarity control, solder wicking control, and bump void control. It's crucial to ensure a high-quality solder bump reflow process to meet the final product reliability requirements. In this paper, a combined formic acid based fluxless and vacuum assisted reflow process is developed for fine pitch plated solder bumping application. A high-volume production (HVM) ready tool has been developed for this process.
Technical Library | 2023-01-17 17:12:33.0
Reflowed indium metal has for decades been the standard for solder thermal interface materials (solder TIMs or sTIMs) in most high-performance computing (HPC) TIM1 applications. The IEEE Heterogeneous Integration Thermal roadmap states that new thermal interface materials solutions must provide a path to the successful application of increased total-package die areas up to 100cm2. While GPU architectures are relatively isothermal during usage, CPU hotspots in complex heterogeneously-integrated modules will need to be able to handle heat flux hotspots up to 1000W/cm2 within the next two years. Indium and its alloys are used as reflowed solder thermal interface materials in both CPU and GPU "die to lid/heat spreader" (TIM1) applications. Their high bulk thermal conductivity and proven long-term reliability suit them well for extreme thermomechanical stresses. Voiding is the most important failure mode and has been studied by x-ray. The effects of surface pretreatment, pressure during reflow, solder flux type/fluxless processing, and preform design parameters, such as alloy type, are also examined. The paper includes data on both vacuum and pressure (autoclave) reflow of sTIMs, which is becoming necessary to meet upcoming requirements for ultralow voiding in some instances.
Technical Library | 2023-08-16 18:13:53.0
In one of our Consumer Electronics projects, a smart lighting company wished to dispense silicone-based LED encapsulation material for two different product sizes. The larger product had a 9mm circular dam which required silicone dispensing flush with the top of the dam. The smaller product had a 1mm LED die that required only the top to be encapsulated. The material consisted of two parts which were mixed by weight in a 1:1 ratio. A phosphor powder was added totaling 10% of the overall weight. The phosphor required agitation to remain suspended.
Technical Library | 2023-09-07 14:38:31.0
A repeat customer specializing in high-technology interconnect, sensor, and antenna solutions, partnered with us to dispense small volumes of solder paste (Indium 10.1 SAC305 T6SG 78%m) onto backplane connectors – gold pads 0.175mm x 0.225mm. We performed a test requiring 0.200mm diameter or smaller dots to demonstrate the dispensing capability required.
Technical Library | 2012-12-17 22:05:22.0
Package on Package (PoP) has become a relatively common component being used in mobile electronics as it allows for saving space in the board layout due to the 3D package layout. To insure device reliability through drop tests and thermal cycling as well as for protecting proprietary programming of the device either one or both interconnect layers are typically underfilled. When underfill is applied to a PoP, or any component for that matter, there is a requirement that the board layout is such that there is room for an underfill reservoir so that the underfill material does not come in contact with surrounding components. The preferred method to dispensing the underfill material is through a jetting process that minimizes the wet out area of the fluid reservoir compared to traditional needle dispensing. To further minimize the wet out area multiple passes are used so that the material required to underfill the component is not dispensed at once requiring a greater wet out area. Dispensing the underfill material in multiple passes is an effective way to reduce the wet out area and decrease the distance that surrounding components can be placed, however, this comes with a process compromise of additional processing time in the underfill dispenser. The purpose of this paper is to provide insight to the inverse relationship that exists between the wet out area of the underfill reservoir and the production time for the underfill process.
Technical Library | 2023-11-09 08:53:45.0
Crafting an Efficient SMT Conformal Coating Line for Double-Sided PCBA In the intricate realm of electronics manufacturing, selecting the ideal SMT conformal coating line can seem like a challenging quest. The pursuit of a solution that seamlessly integrates efficiency, reliability, and performance is the ultimate goal. In this article, we embark on a journey to unravel the secrets of a standard SMT conformal coating line, using a captivating visual guide as our compass. The Symphony Of Components In An SMT Conformal Coating Line Picture a finely orchestrated symphony, with each instrument playing a unique role in this PCB coating process. The star performers in this lineup include: Transfer Conveyor: These act as the stage where the PCB's journey begins. Think of them as the entry and exit points for your precious boards, allowing a smooth, choreographed dance through the line. 1st Coating Machine: As the first movement in this musical journey, this machine, partnered with the initial curing station, lays down the foundation – applying adhesive to one side of the PCB. Inspection Conveyor: After the initial curing, our inspectors take center stage, using these transfer stations to carefully evaluate the coating's quality. 1st Curing Oven: This is where the magic happens. The first curing oven solidifies the adhesive applied in the previous act, setting the tone for a flawless performance. Flipper Machine: The flipper machine takes the spotlight, gracefully turning the PCB to reveal its other side, ensuring both faces receive their share of adhesion. 2nd Coating Machine: With a newfound perspective, the second coating machine takes the stage, applying adhesive to the reverse side of the PCB. 2nd Curing Oven: The grand finale! The second curing oven brings our symphony to a breathtaking close, solidifying the adhesive applied in the second act, creating a harmonious, dual-sided masterpiece. Efficiency Meets Dual-Side Coating This SMT conformal coating line is like a well-choreographed ballet that requires at least two dancers. One stands at the front, carefully loading PCBs onto the stage, guiding them through the first act. After the flip, the second dancer carries them through the second act, with both sides perfectly coated, ensuring a flawless performance for applications requiring dual-sided adhesion. UV Curing Oven For Illuminating Results For applications that embrace UV-curable adhesives, our line includes UV curing ovens, adding a layer of brilliance to the process and ensuring an efficient solidification of adhesives. Transfer Stations With A Touch Of Magic Within this symphony, the transfer stations wear a touch of magic – the second and fourth stations feature enchanting blue glass covers illuminated by embedded LED lights. These stations offer operators a clear view of the adhesive quality, allowing for meticulous inspections. The blue glass covers also act as protective shields, guarding freshly coated PCBs from the ever-present dust fairies. Certified Excellence: European Standards And CE Certification Ensuring that our performance meets the highest standards, our entire ensemble adheres to stringent European safety standards and proudly boasts CE certification, a testament to compliance with safety, health, and environmental protection requirements. A Variety Of Coating Machines For Your Unique Needs Our lineup doesn't just feature one star, but an ensemble of coating machines, including models like I.C.T-T550, I.C.T-T550U, I.C.T-T600, and I.C.T-T650. For an encore performance with detailed specifications of each model, please refer to our dedicated article. Additionally, for a captivating exploration of the right coating valve for your adhesive, please visit our comprehensive guide. Single-Sided PCB Coating For those who prefer a single board, our dedicated article on single-sided PCB coating is a spotlight on this specialized process. In the dynamic world of electronics manufacturing, our SMT conformal coating line stands as a versatile and reliable performance. With dual-sided coating capabilities, adherence to European safety standards, and CE certification, we offer a comprehensive platform for your coating needs. Join us in this symphony and explore our range of coating machines and accessories to enhance your conformal coating process. It's a performance that promises to leave you in awe!
Technical Library | 2010-01-13 12:34:10.0
Micro-sectioning (sometimes referred to as cross-sectioning)is a technique, used to characterize materials or to perform a failure mode analysis, for exposing an internal section of a PCB or package. Destructive in nature, cross-sectioning requires encapsulation of the specimen in order to provide support, stability, and protection. Failures that can be investigated through micro-sectional analysis include component defects, thermo-mechanical failures, processing failures related to solder reflow, opens or shorts, voiding and raw material evaluations.
Technical Library | 2013-07-03 10:31:54.0
It has been demonstrated in numerous pieces of work that stencil printing, one of the most complex PCB assembly processes, is one of the largest contributors to defects (Revelino et el). This complexity extends to prototype builds where a small number of boards need to be assembled quickly and reliably. Stencil printing is becoming increasingly challenging as packages shrink in size, increase in lead count and require closer lead spacing (finer pitch). Prototype SMT assembly can be further divided between industrial and commercial work and the DIYer, hobbyist or researcher groups. This second group is highly price sensitive when it comes to the materials used for the board assembly as their funds are sourced from personal or research monies as opposed to company funds. This has led to development of a lower cost SMT printing stencil made from plastic film as opposed to the more traditional stainless steel stencil used by industrial and commercial users.This study compares the performance of these two traditional materials and their respective impact on solder paste printing including efficiency and print quality.
Technical Library | 2022-02-21 19:49:16.0
The ability to undertake non-destructive testing on semiconductor devices, during both their manufacture and their subsequent use in printed circuit boards (PCBs), has become ever more important for checking product quality without compromising productivity. The use of x-ray inspection not only provides a potentially non-destructive test but also allows investigation within optically hidden areas, such as the wire bonding within packages and the quality of post solder reflow of area array devices (e.g. BGAs, CSPs and flip chips).
Technical Library | 2017-06-22 17:11:53.0
C-mode scanning acoustic microscopy (C-SAM) is a non-destructive inspection technique showing the internal features of a specimen by ultrasound. The C-SAM is the preferred method for finding “air gaps” such as delamination, cracks, voids, and porosity. This paper presents evaluations performed on various advanced packages/assemblies especially flip-chip die version of ball grid array/column grid array (BGA/CGA) using C-SAM equipment. For comparison, representative x-ray images of the assemblies were also gathered to show key defect detection features of the two non-destructive techniques.
