Denuded Zone Formation by High Temperature Inert Anneal of 300 mm Cz-Silicon Wafers : AEPM: Advanced Equipment, Processes and Materials

We investigated the influence of high temperature inert anneals (1150° - 1175°C) in nitrogen and argon on the formation of an oxygen denuded zone (DZ) in 300 mm as-grown Czochralski Silicon (Cz-Si) wafers from three different vendors as an alternative to epitaxial layers as active device zone. An anneal process optimized in time, temperature and gas ambient was found, resulting in a significant reduction in STI etch defects caused by bulk micro defects (BMD). Changes in the Oxygen interstitial concentration were studied as well as the effect of the high temperature anneal on slip line formation. We discuss the underlying mechanisms of the BMD anneal and DZ formation.