ASSEMBLY AND RELIABILITY OF HIGH CTE CERAMIC LAND GRID ARRAYAuthors: Andrew Mawer et al.
Company: Freescale Semiconductor, Inc.
Date Published: 9/25/2005 Conference: SMTA International
LGA eliminates the possibility of spheres being damaged in shipping or handling and resphering for reuse or test is not necessary after removal. The use of Pb-free assembly solder, along with a Pb-free capacitor attach solder interconnect to the LGA substrate, allows the package to be a Pb-free solution.
LGA also has a lower mounted height which may benefit space limited applications and may result in improve delectrical and/or shock performance. This paper outlines a high CTE ceramic LGA SMT assembly process and reliability study that was carried out using SnPb and Pb-free solder pastes. LGAs were assembled to boards with four different stencil thickness and aperture diameter combinations.
Assembly yields and observations for each combination will be reported. Extensive X-ray and crosssectional analyses were carried out to characterize joint geometries and the extent of voiding. The boards were placed into thermal cycling from 0 to 100ºC until >50% failure and post-cycling data and failure analysis results will also be presented.
Members download articles for free:
Not a member yet?
What else do you get when you join SMTA? Read about all of the benefits that go along with membership.
Notice: Sharing of articles is restricted to just your immediate work group. Downloaded papers should not be stored on an external network or shared on the internet.