Authored By:
Mumtaz Y. Bora
Kyocera Wireless Corporation
San Diego, CA 92121 USA
Transcript
The handheld wireless product market place demands products that are small, thin, low-cost and lightweight with improved user interfaces. In addition, the convergence of handheld wireless phones with palmtop computers and Internet appliances is accelerating the need for functional circuits designed with the smallest, low-cost technologies.
The miniaturization of portable electronics and mobile handsets is resulting in thin form factor cell phones, camera modules and Bluetooth packages. The consumer appeal for sleek phones is driving the need for thin PWB roadmaps for the handset.
Qualification of thin PWBs require careful evaluation of PWB stackup for warpage, delamination and successful lead free reflow and rework.
This paper presents the qualification testing of thin PWBs for warpage, cross sectional analysis, shear testing, thermal shock, temperature, humidity testing and drop test for long-term reliability.
Summary
The handheld wireless product market place demands products that are small, thin, low-cost and lightweight and improved user interfaces. In addition, the convergence of handheld wireless phones with palmtop computers and Internet appliances is accelerating the need for functional circuits designed with smallest, low-cost technologies.
The miniaturization of portable electronics and Mobile handsets is resulting in thin form factor cell phones, camera modules and Bluetooth packages. The consumer appeal for sleek phones is driving the need for thin PWB roadmaps for the handset. [1]
Qualification of thin PWBs (less than 0.8mm) require careful evaluation of PWB stackup for warpage, delamination and successful lead free reflow and rework. The paper presents the qualification testing of thin PWBs for warpage characteristics. X-sectional analysis, shear testing, thermal shock, temp. Humidity testing and drop test for long-term reliability
Conclusions
Thin form factor PWBs can be successfully assembled and used in portable products. Proper understanding of the warpage characteristics of the PWBs and packages is essential for a reliable assembly. For success in assembly yields, correct thermo coupling of the PWB and critical packages for both sides A and B reflow is required. The concerns with damaged and misregistered components and cracked interconnects can be addressed by fully characterizing device and substrate warpage behavior prior to production and help reduce in-process defects related to adverse mechanical behaviors.
Initially Published in the IPC Proceedings
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