A BIST method for TSVs pre-bond test

In this paper we present a Built-In-Self-Test (BIST) method dedicated to pre-bond testing of TSVs in 3D stacked integrated circuits. The test method aims to detect full-open and pin-hole defects by measuring the discharge delay of TSVs´ equivalent capacitance. The paper presents an original solution for monitoring the discharge delay of the TSV under test independently of the process variations. Simulation-based results shows that the method is robust w.r.t these variations. The proposed BIST circuitry is small enough to be inserted in the available area between the TSVs.