Dielectric-on-Dielectric Achieved on SiO2 in Preference to W by Water-free Chemical Vapor Depositions with Aniline Passivation

James Huang; Yunil Cho; Victor Wang; Zichen Zhang; Jing Mu; Ajay Yadav; Keith Wong; Srinivas Nemani; Ellie Yieh; Kummel Andrew

doi:10.1021/acsami.3c02278

Dielectric-on-Dielectric Achieved on SiO₂ in Preference to W by Water-free Chemical Vapor Depositions with Aniline Passivation

ACS Appl Mater Interfaces. 2023 May 31;15(21):26128-26137. doi: 10.1021/acsami.3c02278. Epub 2023 May 19.

Authors

Affiliations

¹ Materials Science and Engineering, University of California, San Diego, La Jolla California 92093, United States.
² Electrical and Computer Engineering, University of California, San Diego, La Jolla California 92093, United States.
³ Applied Materials, Inc., Santa Clara, California 95054, United States.
⁴ Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla California 92093, United States.

PMID: 37205770
DOI: 10.1021/acsami.3c02278

Abstract

Selective and smooth dielectric-on-dielectric was achieved by water-free single-precursor chemical vapor deposition (CVD) processes with the help of aniline passivation. Aniline selective passivation was demonstrated on W surfaces in preference to SiO₂ at 250, 300, and 330 °C. After aniline passivation, selective HfO₂, Al₂O₃, and TiO₂ were deposited only on the HF-cleaned SiO₂ surface by water-free single-precursor CVD using hafnium tert-butoxide Hf(O^tBu)₄, aluminum-tri-sec-butoxide (ATSB), and titanium isopropoxide Ti(OⁱPr)₄ as the precursor reactants, respectively. Hf(O^tBu)₄ and Ti(OⁱPr)₄ single-precursor CVD was carried out at 300 °C, while the ATSB CVD process was conducted at 330 °C. HfO₂ and Al₂O₃ nanoselectivity tests were performed on W/SiO₂ patterned samples. Transmission electron microscopy images of the W/SiO₂ patterned samples after deposition demonstrated nanoselectivity and low surface roughness of HfO₂ and Al₂O₃ deposition on the SiO₂ regions only.

Keywords: aluminum-tri-sec-butoxide; aniline selective passivation; area-selective pulsed chemical vapor deposition; hafnium tert-butoxide; titanium isopropoxide; water-free oxide deposition.