Electronics Assembly Knowledge, Vision & Wisdom
Soldering Immersion Tin
Soldering Immersion Tin
This paper focuses on awareness of factors attributed to soldering i-Sn including IMC formations in relation to reflow cycles and solderability performance.
Production Floor

Authored By:
Rick Nichols and Sandra Heinemann - Atotech Deutschland GmbH
,{url:'http://www.circuitinsight.com/videos/programs_final.mp4'}], clip:{autoBuffering:true, autoPlay:true, scaling:'scale' } }).ipad();
Summary
The stimulating impact of the automotive industry has sharpened focus on immersion tin (i-Sn) more than ever before. Immersion tin with its associated attributes, is well placed to fulfill the requirements of such a demanding application.

In an environment dominated by reliability, the automotive market not only has very stringent specifications but also demands thorough qualification protocols. Qualification is ultimately a costly exercise. The good news is that i-Sn is already qualified by many tier one OSATs.

The focus of this paper is to generate awareness of the key factors attributed to soldering i-Sn. Immersion tin is not suitable for wire bonding but ultimately suited for multiple soldering applications. The dominant topics of this paper will be IMC formations in relation to reflow cycles and the associated solderability performance.
Under contamination free conditions, i-Sn can provide a solderable finish even after multiple reflow cycles. The reflow conditions employed in this paper are typical for lead free soldering environments and the i-Sn thicknesses are approximately 1 micrometer.
Conclusions
Whilst i-Sn can be shown to be a reliable final finish for soldering even after multiple thermal ageing tests that could feasibly be encountered in production, uncontrolled external influences can result in poor results. These are not only problematic to i-Sn final finishes and can be eliminated by good practice.

The production environment is a complex one where controls and good practice can help to ensure high yields. This paper proves that i-Sn can provide a reliable solderable finsh with a long shelf life and a compatibility to realistically challenging production environments.
Initially Published in the IPC Proceedings
Submit A Comment

Comments are reviewed prior to posting. Please avoid discussion of pricing or recommendations for specific products. You must include your full name to have your comments posted. We will not post your email address.

Your Name


Company


E-mail


Country


Comments


Authentication

Please type the number displayed into the box. If you receive an error, you may need to refresh the page and resubmit the information.



Related Programs
bullet Solder Column Attachment for Absorbing Large CTE Mismatch
bullet Simple Test for Flux Penetration
bullet Problem Meeting Minimum Hole Fill During Wave Soldering
bullet Reflow Problems on Intrusive Solder Joints
bullet A Control-Chart Based Method for Solder Joint Crack Detection
bullet Pad Cratering and Suggested Solutions
bullet Lead-Free Selective Solder Guidelines
bullet Does Flux Volume Impact Solderability?
bullet BGA Solder Ball Shelf Life
bullet What Causes Non-wetting of OSP Test Pads?
More Related Programs
About | Advertising | Contact | Directory | Directory Search | Directory Submit | Privacy | Programs | Program Search | Sponsorship | Subscribe | Terms

Circuit Insight
6 Liberty Square #2040, Boston MA 02109 USA

Jeff Ferry, Publisher | Ken Cavallaro, Editor/Business Manager

Copyright © Circuitnet LLC. All rights reserved.
A Circuitnet Media Publication