Semiconductor structure and manufacturing method thereof

Abstract

A method includes: receiving a composite substrate including a first region and a second region, the composite substrate comprising a semiconductor substrate and an insulator layer over the semiconductor substrate; bonding a silicon layer to the composite substrate; depositing a capping layer over the silicon layer; forming a trench through the capping layer, the silicon layer and the insulator layer, the trench exposing a surface of the semiconductor substrate in the first region; growing an initial epitaxial layer in the trench; removing the capping layer to form an epitaxial layer from the silicon layer and the initial epitaxial layer; forming a transistor layer over the epitaxial layer, the transistor layer including a first transistor and a second transistor in the first region and the second region, respectively; and forming an interconnect layer over the transistor layer and electrically coupling the first transistor to the second transistor.