The end of node scaling is approaching. Therefore, the need to start scaling the packages is growing constantly. Fan out wafer-level packaging (FO-WLP) offers an efficient solution due to its possibility for high IO count, thin package and short development times. The process flow to build a so called redistribution layer (RDL) requires a full lithography and plating cycle. To ensure a reliable product, all involved process steps need to be tightly monitored and controlled accurately. The challenge here: how to measure step height of pads or under bump metallization (UBM) features on structures that are not completely flat and show height variations. The answer = interferometry.
In this webinar hosted by SMTA, we’ll explore ways to tackle that problem and introduce the work flow of a stable algorithm to evaluate the above mentioned features automatically for different devices. We will discuss how White Light Interferometry (WLI) and Spectral Coherence Interferometry (SCI) can be used to achieve fast and accurate measurements of step heights, critical dimensions (CDs) of pads, UBM structures, as well as polymer thickness. We will share data taken from measurements – displaying full wafer maps, 3D profiles, and identifying the anomalies that are revealed.
- White light interferometry sensor and technology
- Spectral coherence interferometry sensor and technology
- Measurement principles
- Application examples in packaging
- Data evaluation
Who Should Attend:
- R&D Managers
- Laboratory Managers
Recorded April 4, 2017
Duration: 45 minutes
Presenting by Quantum Analytics
Julia Brueckner, PhD
Application Scientist, Quantum Analytics
Julia Brueckner received her PhD in Physical Chemistry at the University of Heidelberg, Germany. She worked for Sentronics Metrology, a Germany-based metrology equipment supplier before she was transferred to the US distributor Quantum Analytics. As an applications engineer, Julia is responsible for promoting optical metrology solutions and providing technical support to customers.