Electronic component solderability assessment algorithm by deep external visual inspection - Dr. Eyal Weiss
Electronic component solderability assessment algorithm by deep external visual inspection
Abstract— Electronic component solderability is an essential capability in electronics manufacturing. It determines an
electronic component’s ability to be reliably and repeatably soldered onto a circuit board in an automated production
scheme. However, conventional solderability assessment is a destructive test that is performed on samples only.
INTRODUCTION: Electronic component solderability
Electronic component solderability is an essential capability in the electronics manufacturing domain. It stands for the ability of an electronic component to be reliably and repeatably soldered onto a circuit board in an automated production environment [1]. To obtain a reliable and repeatable soldering process, the production parameters are optimized by the electronic manufacturer. This process includes managing the board preparations, solder paste dispensing, component placement, and reflow parameters. However, manufacturers rarely evaluate the conditions and solderability of the soldering leads in electronic components prior to assembly. This is because of the assumption that the proficiency of the assembly process is sufficient to mitigate the variations within the acceptable parameters of the component leads. There are several conventional methods to assess the solderability of an electronic component [2].
In the defense industry samples from a component batch that are suspect of poor solderability are required to be inspected according to MIL-STD-202, Method 208 [3].In the automotive industry, the ISO-26262 standard is used [4], [5]. Typically, the testing process involves selecting and testing samples of the components under specified conditions to assess the solder wetting ability on the component leads and the strength of the bond. The evaluation process is either by visual examination of the solder coverage on the leads after the solder dip process or by evaluating the strength of the bond after reflow. This conventional process is manual, labor-intensive, expensive, and performed on samples only.