Advanced structural process monitoring, using in-line FIB

Abstract

In this paper the challenges of incorporating in-line FIB as process monitor will he discussed, for both process qualificaiion phase as well as production phose. Results of advanced FIB capobiliiies using Applied's SEWision G2FIB will be demonstrated on some of Infineon's most challenging process sieps, previously lacking in-line capahiliv. In addiiion, ihe efforts ond results of developing best known method (BKMs) for FIB milling, deposition techniques (capping, and imaging will be discussed and shown comparing resulis to iraditional lab profile measurement iechniques. INTRODUCTIONCross sectioning to reveal multi-layer images is a critical process diagnostics and metrology method used for process-integration analysis and optimization at development phase as well as process window monitoring during production. This is traditionally a task performed in the failure analysis lab. Sending a wafer to the lab for cross section analysis and metrology is time consuming and dictates scrapping of wafers sampled. Advance process requirements and methodology can benefit greatly by implementing in-line cross sectioning capabilities that will allow high volume multi-layer cross section analysis avoiding forfeiting entire wafer yield when sampled. This may be achieved by introducing advanced in-line defect analysis system combining defect review SEM with integrated Focused Ion Beam (FIB). This enables local cross sectioning on wafer surface abiding by requirements of minimal sacrificing of dies on wafer and thus allowing returning wafer to production.