Test bench modeling and characterization for fine pitch wafer level packaged devices

This work describes an interposer hardware for testing fine pitch wafer level packaged devices. It is built to handle multi-gigahertz signal propagation using 100 micron pitch GSG probes. All the components of the test hardware socket such as the SMA connectors, coplanar transmission lines on the PCB and trampoline mesh have been modeled. A sample chip, without bumps on the pads, has also been measured. The measurement and models demonstrate that the test socket performs at 5 GHz with an insertion loss of about 3dB.