US Patent Application 18163649. BUFFER EPITAXIAL REGION IN SEMICONDUCTOR DEVICES AND MANUFACTURING METHOD OF THE SAME simplified abstract

BUFFER EPITAXIAL REGION IN SEMICONDUCTOR DEVICES AND MANUFACTURING METHOD OF THE SAME

Organization Name

Taiwan Semiconductor Manufacturing Company, Ltd.

Inventor(s)

Shahaji B. More of Hsinchu City (TW)

BUFFER EPITAXIAL REGION IN SEMICONDUCTOR DEVICES AND MANUFACTURING METHOD OF THE SAME - A simplified explanation of the abstract

• This abstract for appeared for US patent application number 18163649 Titled 'BUFFER EPITAXIAL REGION IN SEMICONDUCTOR DEVICES AND MANUFACTURING METHOD OF THE SAME'

Simplified Explanation

This method involves creating a semiconductor fin that sticks out from a semiconductor substrate. The fin has two parts: an epitaxial portion and a mesa portion underneath it. The epitaxial portion consists of multiple channel layers and sacrificial layers. The semiconductor substrate has a top surface that is in a specific crystal plane. The method also includes creating a dummy gate structure that spans across the semiconductor fin. Then, the epitaxial portion of the fin adjacent to the dummy gate structure is removed to create a recess. A buffer semiconductor region is grown in this recess, followed by the growth of a source/drain feature on top of the buffer semiconductor region. Finally, the dummy gate structure is replaced with a metal gate structure. The buffer semiconductor region also has a top surface in the same crystal plane as the semiconductor substrate.

Original Abstract Submitted

A method includes forming a semiconductor fin protruding from a semiconductor substrate. The semiconductor fin has an epitaxial portion and a mesa portion under the epitaxial portion. The epitaxial portion has a plurality of channel layers interleaved with a plurality of sacrificial layers. The semiconductor substrate has a top surface in (110) crystal plane. The method also includes forming a dummy gate structure across the semiconductor fin, removing at least the epitaxial portion of the semiconductor fin in a region adjacent the dummy gate structure to form a recess, epitaxially growing a buffer semiconductor region in the recess, epitaxially growing a source/drain feature on the buffer semiconductor region, and replacing the dummy gate structure with a metal gate structure. The buffer semiconductor region has a top surface in (110) crystal plane.