Effect of weak metallic contamination on silicon epitaxial layer and gate oxide integrity

✍ Scribed by D. Mello; C. Coccorese; E. Ferlito; G. Sciuto; R. Ricciari; P. Barbarino; M. Astuto

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 258 KB
• Volume: 46
• Category: Article
• ISSN: 0232-1300
• DOI: 10.1002/crat.201000585

✦ Synopsis

Abstract

The detection of metallic contaminants in microelectronics devices is one of the main issues in production line. In fact they could diffuse rapidly into the silicon bulk and establishing energy states into the silicon energy‐band gap. The presence of trace of metals on the silicon surface can also degrade the gate oxide integrity, cause structural defect in silicon epitaxial layers or anomalies in silicon/gate oxide interface. Usually in semiconductor manufacturing superficial metallic contamination is monitored using Total X‐ray Reflection Fluorescence spectroscopy (TXRF) and performing specific electrical measurements on dedicated capacitor. In this work a weak contamination, undetected by TXRF analysis, was revealed by Transmission Electron Microscopy (TEM) observing lattice damaging and Time of Flight Secondary Ion Mass Spectrometry (ToF‐SIMS) detecting an anomalous Na distribution in depth profile. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)