Novel precleaning treatment for selective tungsten chemical vapor deposition

T. C. Chang*, Y. S. Mor, Po-Tsun Liu, S. M. Sze, Y. L. Yang, M. S. Tsai, C. Y. Chang

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review

1 Scopus citations


The new solutions, hydroxylamine sulfate [(NH2OH)2H2SO4] combined with CuSO4, for cleaning Al via were investigated. It is found that the cleaning capability of hydroxylamine sulfate combined with CuSO4 is better than that of hydroxylamine sulfate. Low via resistance of electrical test structure is obtained if the via is cleaned by this new cleaning solution. The hydroxylamine sulfate can efficiently remove Al3O2 and leave the clean Al on the surface of via. Then, the Cu ion in this new solution will immediately react with clean Al and form a copper passivating layer on the surface of via. The copper is more stable than aluminum in the environment and hard to be oxidized. Therefore, hydroxylamine sulfate combined with CuSO4 can provide excellent cleaning capability for aluminum via holes. Also, the clean surface on the bottom of via is helpful for tungsten nucleation in via during CVD-W deposition. Therefore, a low via resistance and good selectivity of tungsten plug are obtained when the Al via is precleaned with this new solution.

Original languageEnglish
Pages (from-to)451-455
Number of pages5
JournalThin Solid Films
StatePublished - 1 Nov 1999
EventProceedings of the 1999 26th International Conference on Metallurgic Coatings and Thin Films - San Diego, CA, USA
Duration: 12 Apr 199915 Apr 1999


Dive into the research topics of 'Novel precleaning treatment for selective tungsten chemical vapor deposition'. Together they form a unique fingerprint.

Cite this