| 摘要 |
A technique is described for the preparation of buried channels of arbitrary conductivity type in a semiconductor device or integrated circuit containing oxide moats in an epitaxial surface layer. By following a specific sequence of process steps, two mask layers are obtained from a single mask alignment step which permits adjacent regions in the substrate to be doped to different conductivity and type, if desired, prior to the growth of the epitaxial layer. The resulting epitaxial layer has an irregular surface pattern reflecting the shape of the buried structures to faciliate ready alignment with the mask pattern necessary for the production of oxide moats. The resulting structure has a channel buried under the oxide moat region which is used to inhibit the formation of parasitic channels or create a desired channel for device purposes. |
