Defects Created by Helium Implantation at Different Temperatures in Silicon

摘要

Single and multi-energy implantations at different temperatures were performed in silicon single crystals with high dose of helium. The implantation damage were investigated using cross section transmission electron microscopy and thermal desorption spectrometry. A 200 °C implant induces a continuous band of small bubbles ranging between 20 and 650 nm from the surface. After implantation at 800 °C, no bubbles are detected, only extended defects located at the end of range of the damaged profile are observed (EOR defects). Multi-energy implantations at 800 °C performed to obtain a large and constant damage profile shows that the buried zone can be divided into three different layers. The first layer, constituted of faceted bubbles and small clusters, is followed by two other layers free of bubbles. In these two deep layers only extended defects are observed, {113} defects in particular.