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 | 2023-01-17 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 | 2026-03-17 20:51:50.0
The Tintina fault is a major ∼1,000‐km‐long geologic fault in the Yukon Territory of northwestern Canada, previously believed to have last been active around 40 million years ago, but speculated to remain capable of generating large earthquakes. Using new high‐resolution topographic data collected from satellites, airplanes, and drones, we have identified a 130‐km‐long segment of the fault where 2.6 million‐year‐old, and 132 thousand‐year‐old geological formations are laterally shifted across the fault by ∼1,000 and 75 m, respectively. From this, we surmise that the Tintina fault has ruptured in numerous large earthquakes in the recent geologic past, and continues to accumulate strain at an average rate of 0.2–0.8 mm/yr. We further show that the fault has not ruptured in a major earthquake for at least 12 thousand years, and could generate an earthquake of at least magnitude 7.5 in the future. The Tintina fault therefore represents an important, previously unrecognized, seismic hazard to the region.
Technical Library | 2025-11-11 19:37:14.0
Facing inefficiencies and quality control challenges during pre-production, Microboard turned to ScanCAD to improve circuit card assembly inspections. Traditional reliance on Gerber data from board shops resulted in delayed feedback, rework, and scrap--adding as much as 10% to pre-production costs. Manual inspections further slowed the process and left subtle defects undetected. ScanCAD empowered Microboard to perform automated, in-house inspections, identifying issues such as board stretch, over-etching, and component misalignments before they disrupted production. The technology also created digital records for enhanced traceability and quality assurance, a critical feature for regulatory compliance. Since implementing ScanCAD, Microboard has achieved: 40% reduction in pre-production cycle time 40% reduction in line shutdowns due to pre-production errors 20% reduction in pre-production process costs The Executive Director of Technology calls the tool indispensable, particularly for projects involving smaller components and high-complexity assemblies.
Technical Library | 2012-01-26 20:28:34.0
In electronics design, Computer Aided Design (CAD) tools manage part data in a logical schematic view (a part symbol) and a physical PCB view (a part footprint). Yet, a part has a third view, which CAD tools ignore – its supply data (Manufacturer part num
Technical Library | 1999-05-06 14:19:44.0
In many high-performance VLSI designs, including all recent Intel microprocessors, datapath is implemented in a bit-sliced structure to simultaneously manipulate multiple bits of data. The circuit and layout of such structures are largely kept the same for each bit slice to achieve maximal performance, higher designer productivity, and better layout density. There are very few tools available to automate the design of a general datapath structure, most of which is done manually...
Technical Library | 2015-04-03 20:02:31.0
Understanding your process and how to minimize defects has always been important. Nowadays, its importance is increasing with the complexity of products and the customers demand for higher quality. Quality Management Solutions (QMS) that integrate real-time test and inspection results with engineering and production data, can allow the optimization of the entire manufacturing process. We will describe the cost and time benefits of a QMS system when integrated with engineering data and manufacturing processes. We will use real examples that can be derived from integrating this data. This paper also discusses the aspects of Quality Management Software that enables electronic manufacturers to efficiently deliver products while achieving higher quality, reduce manufacturing costs and cutting repair time. Key words: Quality Management Software, ICT, Repair workstations, First Pass Yield, Pareto analysis, Flying Probe, QMS.
Technical Library | 2012-05-17 21:53:39.0
First published in the 2012 IPC APEX EXPO technical conference proceedings. Companies that have initiated internal resources to obtain compliance data have realized that collecting, and more importantly, maintaining the currency of that data requires more
Technical Library | 2018-04-11 22:18:05.0
Millimeter-wave (mmWave) frequency applications are becoming more common. There are applications utilizing PCB technology at 60 GHz, 77 GHz and many other mmWave frequencies. When designing a PCB for mmWave frequency, the properties of the circuit materials need to be considered since they can be critical to the success of the application. Understanding the properties of circuit materials at these frequencies is very important.This paper will give an overview of which circuit material properties are important to mmWave frequency applications using PCBs. There will be data supplied which demonstrates why these properties are essential to the circuit material selection for mmWave applications. Some properties discussed will be dielectric constant (Dk) control, dissipation factor, moisture absorption, thickness control and TCDk (Temperature Coefficient of Dk). Measured comparisons will be shown for insertion loss and Dk versus frequency for different types of circuit materials up to 110 GHz. As part of the test data, the impact on circuit performance due to TCDk and moisture absorption will be shown at mmWave frequencies.
Technical Library | 2019-09-04 21:35:53.0
Since the European Directives, RoHS (Restriction of Hazardous Substances) and REACH (Registration, Evaluation, Authorization and Restriction of Chemicals), entered into force in 2006-7, the number of regulated substances continues to grow. REACH adds new substances roughly twice a year, and more substances will be added to RoHS in 2019. While these open-ended regulations represent an ongoing burden for supply chain reporting, some ability to remain ahead of new substance restrictions can be achieved through full material declarations (FMD) specifically the IPC-1752A Class D Standard (the "Standard"), which was developed by the IPC - Association Connecting Electronic Industries. What is important to the supply chain is access to user-friendly, easily accessible or free, fully supported tools that allow suppliers to create and modify XML (Extensible Markup Language) files as specified in the Standard. Some tools will provide enhancements that validate required data entry and provide real-time interactive messages to facilitate the resolution of errors. In addition, validation and auto-population of substance CAS (Chemical Abstract Service) numbers, and Class D weight rollup validation ensure greater success in the acceptance of the declarations in customer systems that automate data gathering and reporting. A good tool should support importing existing IPC-1752A files for editing; this capability reduces the effort to update older declarations and greatly benefits suppliers of a family of products with similar composition. One of the problems with FMDs is the use of "wildcard" non-CAS numbers based on a declarable substance list (DSL). While the substances in different company's lists tend to have some overlap, no two DSL’s are the same. We provide an understanding of the commonality and differences between representative DSLs, and the ability to configure how much of a non-DSL substance percent is allowed. Case studies are discussed to show how supplier compliance data, can be automatically loaded into the customer's enterprise compliance system. Finally, we briefly discuss future enhancements and other developments like Once an Article, Always an Article (O5A) that will continue to require IPC standards and supporting tools to evolve.
