Nondestructive characterization of oxygen‐ion‐implanted silicon‐ on‐insulator using multiple‐angle ellipsometry

Silicon‐on‐insulator formed by high‐dose and high‐energy oxygen ion implantation in silicon, called SIMOX (separation by implanted oxygen), has been characterized nondestructively by multiple‐angle ellipsometry using a He–Ne laser at 632.8 nm. A multilayered model exhibiting two interlayers, one between the top silicon layer and the buried oxide layer and the other between the buried oxide and the substrate silicon, offers a simple representation of SIMOX. The difference between low‐temperature furnace anneal (1150 °C) and an additional high‐temperature rapid thermal anneal (1150+1350 °C) on as‐implanted wafers is shown by the better agreement between the theoretical model and the experimental results for the high‐temperature annealed SIMOX sample.