Silicon nitride CESL removal without gate cap height loss and resulting device

• Main Authors: Liu Jinping, Sheng Haifeng, Shu Jiehui
• Format: Patent
• Language: English
• Published: 27.02.2018
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

A method of removing the CESL from small canyon TS structures of a MOSFET device while maintaining gate cap height and the resulting device are provided. Embodiments include providing two gates laterally separated over and perpendicular to a fin of a semiconductor device, each gate having sidewall spacers and a nitride cap; forming a conformal SiN CESL on bottom and side surfaces of a trench formed between opposing spacers between the gates; filling the trench with oxide; planarizing the spacers, nitride caps, oxide, and CESL; removing the oxide; forming a topological flat-SiN layer over the spacers, nitride caps, and CESL; removing the topological flat-SiN layer from side and bottom surfaces of the trench; removing the CESL and the topological flat-SiN layer down to a top surface of the spacers; and performing contact metallization.