US Patent Application 18446674. TRANSISTOR ISOLATION STRUCTURES simplified abstract

TRANSISTOR ISOLATION STRUCTURES

Organization Name

Taiwan Semiconductor Manufacturing Company, Ltd.

Inventor(s)

Mrunal Abhijith Khaderbad of Hsinchu (TW)

Keng-Chu Lin of Ping-Tung (TW)

Yu-Yun Peng of Hsinchu (TW)

TRANSISTOR ISOLATION STRUCTURES - A simplified explanation of the abstract

This abstract first appeared for US patent application 18446674 titled 'TRANSISTOR ISOLATION STRUCTURES

Simplified Explanation

The patent application describes a method for creating spacer structures in nanostructure transistors.

• The method involves forming a fin structure with alternating nanostructure elements on a substrate.
• The edge portions of the nanostructure elements are etched to create spacer cavities.
• A spacer layer is then deposited to fill the spacer cavities.
• The spacer layer is treated with a microwave-generated plasma to create an oxygen concentration gradient within the layer.
• The treated portion of the spacer layer is removed using an etching process, with the removal rate based on the oxygen concentration gradient.

Original Abstract Submitted

The present disclosure is directed to method for the fabrication of spacer structures between source/drain epitaxial structures and metal gate structures in nanostructure transistors. The method includes forming a fin structure with alternating first and second nanostructure elements on a substrate. The method also includes etching edge portions of the first nanostructure elements in the fin structure to form spacer cavities, and depositing a spacer layer on the fin structure to fill the spacer cavities. Further, treating the spacer layer with a microwave-generated plasma to form an oxygen concentration gradient within the spacer layer outside the spacer cavities and removing, with an etching process, the treated portion of the spacer layer. During the etching process, a removal rate of the etching process for the treated portion of the spacer layer is based on an oxygen concentration within the oxygen concentration gradient.