Study of Copper Surface Preparation by Sequential Atomic Layer Wet Etching and Laser Annealing Treatments. (15th August 2017)

• Record Type: Journal Article
• Authors: Iwasaki, Akihisa; Akanishi, Yuya; Mazzamuto, Fulvio; Kesters, Els; Le, Quoc Toan; Holsteyns, Frank
• Is Part Of: ECS transactions. Volume 80:Number 2(2017)
• Page Start: 233
• Page End: 241
• Publication Date: 2017-08-15
• Subjects: Electrochemistry -- Periodicals; Electrochemistry; Periodicals; Electronic journals; Electronic journal; 541.37
• DOI: 10.1149/08002.0233ecst
• Languages: English
• ISSNs: 1938-5862

Abstract

Abstract : Atomic scale surface preparation, e.g. atomic layer etching, cleaning, local surface modifications and selective area deposition, becomes increasingly important for device scaling at sub-10 nm technology nodes in order to meet more stringent process variations and the highly selective process requirements. In the fully self-aligned via process, a topography is created by recess etching the underlying metal (copper) layer using chemical mixtures. In addition to a high compatibility with the materials exposed, one of the key requirements is to control the copper recessing such that the change in its roughness is kept at a minimum. The fundamental understanding and control of the polycrystalline surface reactions and interactions at the atomic scale are needed. In this paper, we will demonstrate the copper recess process for atomic layer wet etching (ALWE) with combination of laser thermal annealing (LTA) for surface smoothening.