Defect transferred and lattice mismatched epitaxial film

摘要

An embodiment uses a very thin layer nanostructure (e.g., a Si or SiGe fin) as a template to grow a crystalline, non-lattice matched, epitaxial (EPI) layer. In one embodiment the volume ratio between the nanostructure and EPI layer is such that the EPI layer is thicker than the nanostructure. In some embodiments a very thin bridge layer is included between the nanostructure and EPI. An embodiment includes a CMOS device where EPI layers covering fins (or that once covered fins) are oppositely polarized from one another. An embodiment includes a CMOS device where an EPI layer covering a fin (or that once covered a fin) is oppositely polarized from a bridge layer covering a fin (or that once covered a fin). Thus, various embodiments are disclosed from transferring defects from an EPI layer to a nanostructure (that is left present or removed). Other embodiments are described herein.

主权项

1. An apparatus comprising:
a fin structure including a fin top and opposing fin sidewall portions extending from the fin top towards a substrate; a bridge layer including opposing bridge layer sidewall portions respectively directly contacting the opposing fin sidewall portions; and an epitaxial (EPI) layer comprising opposing EPI sidewall portions respectively directly contacting the opposing bridge layer sidewall portions; wherein a lattice constant differential between the bridge layer and fin structure is less than a lattice constant differential between the bridge layer and the EPI layer wherein a single plane, orthogonal to a long vertical axis of the fin structure, intersects the fin structure over a first area and the EPI sidewalls over a second area and the second area is greater than the first area.