Jump to main content
Jump to site search

Issue 10, 2003
Previous Article Next Article

New powerful reagents based on dihalogen/N,N′-dimethylperhydrodiazepine-2,3-dithione adducts for gold dissolution: the IBr case

Author affiliations

Abstract

The synthesis, X-ray structure [monoclinic, P21/n, a = 12.1690(1), b = 7.8360(1), c = 14.4250(1) Å, β = 113.808(2)°], spectroscopic and electrochemical characterization of a new powerful reagent based on the iodine monobromide adduct of the N,N′-dimethylperhydrodiazepine-2,3-dithione (Me2dazdt) ligand, able to oxidize gold metal in a one-step reaction under mild conditions, is reported. The gold metal dissolution has been performed on gold powder, wires and Au/Ti thin layers. The oxidation product has been isolated and structurally characterised as [Au(Me2dazdt)Br2]IBr2 [monoclinic, C2/c, a = 26.523(8), b = 10.191(6), c = 14.549(7) Å, β = 111.57(2)°]. The metal is essentially within a square planar geometry, Me2dazdt acts as an S,S chelating ligand and two bromide ligands complete the geometry around the metal. The IBr2 counteranion is essentially linear and shows I–Br bond lengths slightly asymmetric [Br(4)–I(1) 2.742(3), Br(3)–I(1) 2.682(2) Å]. A comparison with the gold removal from Si/SiO2/Au/Ti thin layers of comparable thickness to that found in microelectronic devices, by using THF solutions of IBr and I2 adducts of the Me2dazdt donor, as well as the currently used I2/I aqueous solutions, shows that these dihalogens-adducts produce a quantitative gold removal in shorter times and leaving the underlying layer perfectly clean, and are thus highly desirable as new etching agents in the gold-based technology of semiconductor devices.

Graphical abstract: New powerful reagents based on dihalogen/N,N′-dimethylperhydrodiazepine-2,3-dithione adducts for gold dissolution: the IBr case

Back to tab navigation

Supplementary files

Article information


Submitted
21 Oct 2002
Accepted
13 Dec 2002
First published
23 Apr 2003

Dalton Trans., 2003, 1969-1974
Article type
Paper

New powerful reagents based on dihalogen/N,N′-dimethylperhydrodiazepine-2,3-dithione adducts for gold dissolution: the IBr case

L. Cau, P. Deplano, L. Marchiò, M. L. Mercuri, L. Pilia, A. Serpe and E. F. Trogu, Dalton Trans., 2003, 1969
DOI: 10.1039/B210281A

Social activity

Search articles by author

Spotlight

Advertisements