Semiconductor structure with self-aligned wells and multiple channel materials

摘要

Embodiments of the present invention provide a semiconductor structure having a strain relaxed buffer, and method of fabrication. A strain relaxed buffer is disposed on a semiconductor substrate. A silicon region and silicon germanium region are disposed adjacent to each other on the strain relaxed buffer. An additional region of silicon or silicon germanium provides quantum well isolation.

主权项

1. A method of forming a semiconductor structure, comprising:
forming an n-doped, stress relaxed epitaxial first silicon germanium layer having a first germanium concentration onto a semiconductor substrate; depositing a compressively strained epitaxial second silicon germanium layer having a second germanium concentration onto the first silicon germanium layer, wherein the second germanium concentration is higher than the first germanium concentration; removing a portion of the second silicon germanium layer over a first region to create exposed regions of the first silicon germanium layer, thereby forming a preserved portion of the second silicon germanium layer over a second region; counterdoping to p-type the exposed regions of the first silicon germanium layer that are not covered by the second silicon germanium layer; selectively depositing a tensile strained, epitaxial silicon layer in the first region; and forming a plurality of shallow trench isolation regions in the first region and the second region of the second silicon germanium layer.