Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403

공학

한국표면공학회지 (38권1호 28-36)

The Effects of the Annealing on the Reflow Property of Cu Thin Film

열처리에 따른 구리박막의 리플로우 특성

김동원;김상호;
Kim Dong-Won;Kim Sang-Ho;

경기대학교 재료공학과;한국기술교육대학교 신소재공학과;
Department of Materials Science and Engineering, Kyonggi University;Department of Materials Engineering, Korea University of Technology and Education, Chungnam;

Abstract

In this study, the reflow characteristics of copper thin films which is expected to be used as interconnection materials in the next generation semiconductor devices were investigated. Cu thin films were deposited on the TaN diffusion barrier by metal organic chemical vapor deposition (MOCVD) and annealed at the temperature between 250℃ and 550℃ in various ambient gases. When the Cu thin films were annealed in the hydrogen ambience compared with oxygen ambience, sheet resistance of Cu thin films decreased and the breakdown of TaN diffusion barrier was not occurred and a stable Cu/TaN/Si structure was formed at the annealing temperature of 450℃. In addition, reflow properties of Cu thin films could be enhanced in H₂ ambient. With Cu reflow process, we could fill the trench patterns of 0.16～0.24 11m with aspect ratio of 4.17～6.25 at the annealing temperature of 450℃ in hydrogen ambience. It is expected that Cu reflow process will be applied to fill the deep pattern with ultra fine structure in metallization.

Keywords

Reflow;Copper film;TaN Diffusion Barrier;Pattern filling;Giga DRAM;