Electroless Co(W,P) and Co(Mo,P) deposition for Cu metallization applications

Author

Shacham-Diamand, Y. ; Zylberman, A. ; Petrov, N. ; Sverdlov, Y.

Author_Institution

Dept. of Phys. Electron., Tel-Aviv Univ., Ramat-Aviv, Israel

Volume

1

fYear

2001

fDate

2001

Firstpage

410

Abstract

The barrier properties against Cu diffusion of thin-film (< 30 nm) Co(P) alloys are significantly improved when tungsten is added. It is not known whether the barrier properties are due to tungsten or any other refractory metal will have a similar effect. In this work we present a novel electroless cobalt-molybdenum-phosphorous Co(Mo,P) process. Both Co(W,P) and Co(Mo,P) deposition solutions were studied and we present their characteristics such as deposition rate and solid composition. We also present the thin film resistivity and show that the Mo alloy resistivity is higher than that of the W alloy. Auger electron Spectroscopy (AES) and X-ray Photon Spectroscopy (XPS) determined the film composition. The corrosion resistance of Co alloy/Cu/Co-alloy structures were studied by measuring the thin film resistance versus time at elevated temperatures, up to 350°C. We conclude that both W and Mo alloy have similar barrier and corrosion protection priorities. Therefore, the improved barrier properties, as compared to Co(P) alloy is due the refractory metal and not specific to W

Keywords

Auger electron spectra; ULSI; X-ray photoelectron spectra; cobalt alloys; copper; corrosion protective coatings; corrosion resistance; diffusion barriers; electrical resistivity; electroless deposited coatings; electroless deposition; integrated circuit metallisation; molybdenum alloys; phosphorus alloys; tungsten alloys; 30 nm; 350 C; AES; Auger electron spectroscopy; Co alloy/Cu/Co alloy structures; CoMoP deposition solution; CoMoP-Cu; CoWP deposition solution; CoWP-Cu; Cu diffusion; Cu metallization applications; X-ray photon spectroscopy; XPS; barrier properties; corrosion resistance; deposition rate; electroless CoMoP process; refractory metal; solid composition; thin film resistivity; thin-film Co alloys; Cobalt alloys; Conductivity; Copper alloys; Corrosion; Electrons; Metallization; Solids; Spectroscopy; Transistors; Tungsten;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State and Integrated-Circuit Technology, 2001. Proceedings. 6th International Conference on

Conference_Location

Shanghai

Print_ISBN

0-7803-6520-8

Type

conf

DOI

10.1109/ICSICT.2001.981506

Filename

981506