A recursive un-termination method for nondestructive in situ S-parameter measurement of hermetically encapsulated packages

In this paper, we analyze the performance of a newly introduced recursive un-termination method for nondestructive in situ S-parameter measurements of multiport packages. The fundamental limitations of the method are statistically analyzed and compared to conventional two-port probing techniques. The methodology is based on programmable terminations fully integrated in a standard silicon process technology (integrated-circuit chip) and a recursive un-terminating method implemented in software. To demonstrate the validity of the technique, results for a chip-on-board packaging technology have been compared to high-frequency electromagnetic simulations and direct two-port probing techniques.