Comparison of Self-Assembled Monolayers Using 3-Aminopropyltrimethoxysilane and Decyltrimethoxysilane in Vapor Phase for Porous SiOCH Dielectrics

Abstract

Self-assembled monolayers (SAMs) are the emerging materials to act as barriers in the back-end-of-line interconnects for advanced technological nodes. In this study, SAMs were formed on the porous SiOCH (p-SiOCH) films by using different precursors: 3-Aminopropyltrimethoxysilane (APTMS) or decyltrimethoxysilane (DTMOS), in the vapor phase. Effects of SAMs precursors on the electrical characteristics and reliability of p-SiOCH films were characterized and compared. Experimental results indicated that both SAMs derived from APTMS and DTMOS enhanced the breakdown field and time-dependent dielectric breakdown, provided Cu barrier capacity, and promoted adhesion with Cu. In particular, APTMS-SAMs had a larger improvement, but a larger increase in the dielectric constant was observed as compared to DTMOS-SAMs. Therefore, SAMs derived from APTMS are a promising candidate for sub-nanometer barrier application for advanced interconnects.