Patent ID: 6031261
Filing Date: 2000-02-29
Classification: H01L

Abstract:
A silicon-on-insulator semiconductor device comprising:a silicon substrate;a continuous first buried insulating layer within the substrate, the first buried layer defining an upper substrate above the first buried layer and a lower substrate below the first buried layer, the upper substrate having a hole, the first buried layer having a hole substantially aligned with the hole through the upper substrate;a lower doped region of a first conductivity type within the lower substrate below the hole through the first buried layer;a continuous second buried insulating layer within the lower substrate, the second buried layer bounding from below the lower doped region;upper doped regions of the first conductivity type within the upper substrate to either side of the hole through the upper substrate;a epitaxial layer on the upper substrate and on the lower substrate over the lower doped region, regions of the epitaxial layer over the lower doped region forming a trench;conformal insulating film lining the trench;a conductive layer on the conformal insulating film; anddoped regions of a second conductivity type within both the upper substrate and the epitaxial layer to either side of the trench.