Semiconductor device is produced by (a) forming a field oxide layer (2) on a section of a Si substrate (1); (b) forming a conducting layer pattern so that it overlaps the field oxide layer so the conducting layer pattern is insulated from the Si substrate; (a) forming a protective intermediate layer-insulating film (7) on the arrangement produced; (d) etching a contact region of the insulating film (7) to form a contact hole (30) to expose part of the layer pattern, where a region of the field oxide layer is etched as a result of the misalignment of the contact mask and a region of the Si substrate is exposed by a contact hole; (e) selectively depositing epitaxial single crystalline Si on the exposed region of the Si substrate, oxidising the epitaxial single crystalline Si up to a required depth to form an oxide layer (3); and (f) forming a metal wire (10), which is electrically connected to the conducting layer pattern and electrically insulated from the Si substrate.
