Balancing Parallel Test Productivity With Yield & Cost


Parallel test is used for nearly every device produced by fabs and OSATs, but it can reduce yield and increase the cost of test boards and operations. This is a well-understood tradeoff for ensuring consistent test accuracy across multiple sites and reducing test time. Collectively, ATEs and multi-site test boards — DUT interface boards (DIBs), probe cards, and load boards — significantl... » read more

Bump Co-Planarity And Inconsistencies Cause Yield, Reliability Issues


Bumps are a key component in many advanced packages, but at nanoscale levels making sure all those bumps have a consistent height is an increasing challenge. Without co-planarity, surfaces may not properly adhere. That can reduce yield if the problem is not identified in packaging, or it can cause reliability problems in the field. Identifying those issues requires a variety of process steps... » read more

Growing Challenges With Wafer Bump Inspection


As advanced packaging goes mainstream, ensuring that wafer bumps are consistent has emerged as a critical concern for foundries and OSATs. John Hoffman, computer vision engineering manager at CyberOptics, talks about the shift toward middle-of-line and how that is affecting inspection and metrology, why there is so much concern over co-planarity and alignment, how variation can add up and creat... » read more