21 May 1993 Improvement of metal step coverage of VLSI device structures in a manufacturing environment
Author Affiliations +
Abstract
Methods of improving aluminum alloy step coverage, such as high temperature and low power processing, have become well known. Unfortunately, these methods nearly always have drawbacks such as throughput. The process, therefore, needs to be optimized on a case by case basis. An example is provided in this paper for the case of 0.95 micron contacts (1.20 aspect ratio) starting with double level Al-0.5% Cu-1.0% Si with TiN barrier under first level metal and pure Ti under second level metal; 30% step coverage deemed acceptable. Another drawback to standard high temperature Al alloy deposition is the problem of random metal voids. Methods to alleviate this problem are also discussed. Thus there are 2 distinct types of step coverage issues that must be considered separately: (1) inherent step coverage, and (2) random voids. Optimization of each needs to be performed independently.
© (1993) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Rob B. MacNaughton, Rob B. MacNaughton, T. H. Wonacott, T. H. Wonacott, De-Dui Liao, De-Dui Liao, Hoang Huy Hoang, Hoang Huy Hoang, "Improvement of metal step coverage of VLSI device structures in a manufacturing environment", Proc. SPIE 1805, Submicrometer Metallization: Challenges, Opportunities, and Limitations, (21 May 1993); doi: 10.1117/12.145469; https://doi.org/10.1117/12.145469
PROCEEDINGS
15 PAGES


SHARE
Back to Top