Component Packaging
“Reliability Testing of Advanced Semiconductors Using Embedded Chip Build-Up (ECBU) Packaging Technology”
Authors: Shane Lewis, Tan Zhang, Richard J. Saia, Paul A. McConnelee, Kishor V. Desai, Krishnaswami Srihari, Donald P. Cunningham and Charles G. Woychik
Abstract: Embedded chip build-up (ECBU) is an advanced packaging technology targeting high-end microprocessors and video processors. An overview of the performance advantages offered by this technology for high I/O count, high power dissipation and high clock rate chips is covered. This paper shows data of packages fabricated in this technology that meet Jedec qualification specifications, therefore making this packaging technology attractive for the stringent reliability demands for high-end processor applications. Reliability data of ECBU packages using conventional and advanced copper low-K advanced semiconductors are presented for a number of reliability tests. (SMTA International, August 2008)
Pb-Free Reliability
“Improving Hole-Fill in Lead-Free Soldering of Thick Printed Circuit Boards with OSP Finish”
Authors: Jing Li, Pei-Fang Jennifer Tsai, Krishnaswami Srihari, Layag-Junell Abarquez, Jianyeou Yong, Chongchit Chew, Mulugeta Abtew and Robert Kinyanjui;
This e-mail address is being protected from spambots. You need JavaScript enabled to view it
.
Abstract: The challenge in the Pb-free wave soldering of thick (0.080" and above) PCBs lies in achieving desirable hole-fill. Inadequate hole-fill can be improved by sufficient preheat, higher pot temperature and more active flux. However, increasing processing temperatures could be limited because of the thermal tolerances of the laminate and components. Further, it has been reported OSP coating is suspected to degrade under high processing temperatures. Consequently, copper underneath the OSP layer may get oxidized, which can lead to poor wetting. This research focused on hole-fill issues pertaining to thick PCBs with an OSP surface finish that were wave soldered with SAC 305 solder. Test vehicles (0.095" thick) with five different pinhole gap distances (0.00592", 0.00611", 0.00669", 0.00761" and 0.0115") were used in this study. Two factors were considered for the OSP coating layer: increasing OSP coating thickness and increasing the roughness between the copper and OSP layer by applying microetch processing. Hole-fill penetration percentage was measured by x-ray inspection, and more than 50% hole-fill percentage was used as the acceptance criteria. Results showed microetching had no effect on hole-fill percentage. Doubling the OSP layer thickness from 0.2 to 0.4 µm for the smallest pinhole gap distance of 0.00592" increased the hole-fill rejection rate 14%. However, the OSP layer thickness had no significant effect on the hole-fill rejection rate for pinhole gap distances of 0.00669", 0.00761" and 0.0115". For the pinhole gap distance of 0.00611", there was a trend that thinner OSP could lead to better performance. (SMTA International, August 2008)
Project Management
“Applying Project Management Methodologies in Electronics Manufacturing”
Author: Lee Whiteman,
This e-mail address is being protected from spambots. You need JavaScript enabled to view it
.
Abstract: Project management is defined as the application of knowledge, skills, tools, and techniques to project activities to meet project requirements. It is a discipline used to define goals, plan and monitor tasks and resources, identify and resolve issues, and control costs and budgets for a specific project. There are five phases to the project management process: opportunity assessment, initiating, planning, executing/controlling, and closing. These methodologies have been applied to many technical applications in the commercial, information technology and government environments. Research has shown companies that apply project management disciplines outperform competitors that do not. Applying these disciplines is consistent with introducing Six-Sigma, Lean manufacturing, and continuous process improvement initiatives to the design engineering and production environment. This paper covers how project management methodologies can be applied to electronics manufacturing. (SMTA International, August 2008)
Soldering Pallets
“Optimizing Pallet Materials for Long Life and Ease of Machining”
Author: Raj Savara,
This e-mail address is being protected from spambots. You need JavaScript enabled to view it
.
Abstract: This paper presents seven different materials used for the production of wave and reflow solder pallets. The goal of this study was to depict machining capabilities for depth, wall thickness, and accuracy of machining for each of the seven materials presented. Also, a Pb-free wave pallet (used for a high-volume PCB product) was built out of each of the materials under test. Each pallet was tested for the purpose of showing long-term wear effects over multiple heat cycle run times; monitoring pallet flatness for heat warping of the pallet; wall thickness changes, and overall changes in surface condition. (IPC Apex, April 2008)
Circuits Assembly provides abstracts of papers from recent industry conferences and company white papers. With the amount of information increasing, our goal is to provide an added opportunity for readers to keep abreast of technology and business trends.
|
