Accurate Sub-micron Device Delayering of Plan View TEM Specimens By Ar Ion Milling

With the introduction of new materials, new device structures, and shrinking device dimensions, failure mechanisms evolve, which can make identifying defects challenging. Therefore, an accurate and controllable delayering process to target defects is desirable. We present a workflow comprised of bulk device delayering by broad Ar ion beam milling, plan view specimen preparation by focused ion beam tool, followed by site-specific delayering by concentrated Ar ion beam milling. The result is an accurately delayered device, without sample preparation-induced artifacts, that is suitable for uncovering defects during physical failure analysis.