Abstract: An embodiment of a multilayer wafer according to the invention includes a base substrate, a first layer associated with the base substrate, and a second layer on the first layer on side opposite from the base substrate in an axial direction and having a lateral edge. The first layer includes a ridge that protrudes axially and is disposed laterally adjacent the second layer measured in a direction normal to the axial direction for protecting the lateral edge. This ridge can surround portion the lateral edge in an axial cross-section for preventing edge falls. Also, the ridge can have an axial height greater than the axial thickness of the second layer. In one embodiment, the second layer includes an oxydizable semiconductor and the first layer includes an oxidized insulator.

Abstract: An embodiment of a multilayer wafer according to the invention includes a base substrate, a first layer associated with the base substrate, and a second layer on the first layer on side opposite from the base substrate in an axial direction and having a lateral edge. The first layer includes a ridge that protrudes axially and is disposed laterally adjacent the second layer measured in a direction normal to the axial direction for protecting the lateral edge. This ridge can surround portion the lateral edge in an axial cross-section for preventing edge falls. Also, the ridge can have an axial height greater than the axial thickness of the second layer. In one embodiment, the second layer includes an oxydizable semiconductor and the first layer includes an oxidized insulator.

Abstract: The invention relates to a process for the treatment of substrates (1) for microelectronics or optoelectronics comprising a working layer (6) at least partially composed of an oxidizable material on at least one of their faces, this process comprising: a first sacrificial oxidation stage for removing material constituting the working layer (6) over a certain surface thickness of each substrate (1), a stage of polishing (200) the face which has been subjected to the first sacrificial oxidation stage (100), and a second sacrificial oxidation stage for again removing material constituting the working layer (6) on the polished face (17).

Abstract: The invention relates to a process for the treatment of substrates (1) for microelectronics or optoelectronics comprising a working layer (6) at least partially composed of an oxidizable material on at least one of their faces, this process comprising: