METHODS FOR MANUFACTURING METAL GATES

摘要

Provided are methods for making metal gates suitable for FinFET structures. The methods described herein generally involve forming a high-k dielectric material on a semiconductor substrate; depositing a high-k dielectric cap layer over the high-k dielectric material; depositing a PMOS work function layer having a positive work function value; depositing an NMOS work function layer; depositing an NMOS work function cap layer over the NMOS work function layer; removing at least a portion of the PMOS work function layer or at least a portion of the NMOS work function layer; and depositing a fill layer. Depositing a high-k dielectric cap layer, depositing a PMOS work function layer or depositing a NMOS work function cap layer may comprise atomic layer deposition of TiN, TiSiN, or TiAlN. Either PMOS or NMOS may be deposited first.