Source of Metals in Si and Ge Crystal Growth and Processing

© Springer International Publishing AG, part of Springer Nature 2018. First, metal contamination during Si and Ge wafer growth and wafering will be discussed. Wet wafer cleaning processes, although intended to remove contaminants from the wafer surface, can actually deposit metals, depending on a number of parameters. Optimal cleaning recipes for both Si and Ge wafers are discussed. Alternatively, one can consider dry vapor phase cleaning. Photoresist deposition and stripping is another source of metal contamination. Issues with wafer handling will be discussed although they are nowadays largely under control. On the other hand, ion implantation remains a process step, requiring regular metal contamination monitoring. While the lowering of the thermal budget has reduced the occurrence of contamination, fast diffusing metals can still penetrate the semiconductor material. Finally, the use of metal layers and its impact on metal contamination is highlighted in the last section of this chapter.

ISBN:978-3-319-93924-7

Publication year:2018