| 摘要 |
A method for fabricating a high-voltage device substrate comprising the steps of forming a pad oxide layer and a mask layer over a substrate. Then, the pad oxide layer and the mask layer are patterned to define a region for a first ion implantation. Next, the exposed substrate is oxidized to form a field oxide layer. Thereafter, the mask layer is removed followed by a first ion implantation. Next, a portion of the field oxide layer is removed, and then a second ion implantation is performed implanting ions into the exposed substrate. Then, a conformal oxide layer is formed over the substrate surface. Next, a high temperature drive-in and oxidation operation is carried out, in which ions in the first ion implanted region and the second ion implanted region are driven deeper into the substrate interior, and at the same time the substrate above those regions are oxidized. Finally, the oxide layer on the substrate surface is removed, and then an epitaxial layer is formed over the substrate.
|
