IWLPC (Wafer-Level Packaging) Conference Proceedings


Sub-µM 3D For RDL Structures In FO-WLP and Advanced Packaging Using Mult-Sensor Interferometry

Authors: Moritz Jurgschat, Matthias Weber and Ramon Tuason
Company: Sentronics Metrology GmbH and Quantum Analytics
Date Published: 10/18/2016   Conference: IWLPC (Wafer-Level Packaging)


Abstract: FO-WLP has many different process flows, all of which require at least one redistribution layer (RDL) [1]. The manufacturing of this layer involves a full lithography and plating process that needs to be monitored accordingly in a non-destructive metrology loop.

This paper presents a versatile state-of-the-art metrology tool that is capable of measuring the complete process flow with its multi-sensor approach. A high-resolution white-light interferometer (WLI) is used to measure the step heights and CDs of UBM structures with sub-µm vertical and horizontal resolution. The patented Spectral Coherence Interferometry (SCI) technology is used to measure the coating thickness before the exposure step. This is done with a rate of up to 4 kHz enabling full wafer maps to optimize typical areas of low yield such as the center and edge of the wafer.

Key Words: 

Under Bump Metallization (UBM), Redistribution Layer (RDL), Fan-Out Packaging, Mold Wafer, White Light Interferometry, Spectral Coherence Interferometry, Critical Dimension (CD)



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.


Back


SMTA Headquarters
6600 City West Parkway, Suite 300
Eden Prairie, MN 55344 USA

Phone +1 952.920.7682
Fax +1 952.926.1819