This document describes design of test structures needed to assess the reliability of aluminum-copper, refractory metal barrier interconnect systems. This includes any metal interconnect system where a refractory metal barrier or other barrier material prevents the flow of aluminum and/or copper metal ions from moving between interconnect layers. This document is not intended to show design of test structures to assess aluminum or aluminum-copper alloy systems, without barriers to Al and Cu ion movement, nor for Cu only metal systems. Some total interconnect systems might not include barrier materials on all metal layers. The structures in this standard are designed for cases where a barrier material separates two Al or Al alloy metal layers. The purpose of this document is to describe the design of test structures needed to assess electromigration (EM) and stress-induced-void (SIV) reliability of AlCu barrier metal systems.