TEM investigation on top Si layer and buried oxide layer in silicon wafer implanted with low dose at low energy

Microstructures of as-received Si wafers prepared by Separation by Implanted Oxygen (SIMOX) techniques have been investigated by means of high-resolution transmission electron microscopy (TEM) with interest mainly in the top Si layer and the buried oxide (BOX) layer which were developed in the production process. Cross-sectional TEM and HRTEM micrographs clearly reveal the existence of thermally produced oxide layers over the Si top interfaces in both the protectively capped and uncapped Si wafers implanted with different doses of oxygen ions at low fixed energy level, and before the annealing process. The thickness of the top Si layer and the BOX layer have been measured and it is apparent that the thickness of these layers relates to the thermally grown oxide layer covering the top Si layer. The TEM analysis allows an understanding and explanation to be made of the different deposition and growth processes of the thermal oxide layers that cover the top Si layers.