Laser Photochemical Deposition of Gold from Trialkylphosphine Alkylgold(I) Complexes

Abstract

The deposition of gold bearing tracks, by the argon ion laser photolysis at 257 nm of RAuI-PR3, R,R = C2H5, CH3, is reported, Deposits were obtained on optically polished fused quartz and (100) n-type single crystal silicon with a thermally grown oxide layer (3000 A). Tracks were deposited at a range of scan speeds from 0 to 200 pm s-l and characterized by scanning electron microscopy (SEM), laser ionization mass analysis (LIMA), and scanning profilometry.Electrical resistivities as low as 4.51 pQ cm, within a factor of 3 of the value for bulk gold (2.44 p& cm), were measured for tracks deposited a t 40 mW and a scanning speed of 7.5 pm s-l. However, the electrical conductivity of the deposits is highly sensitive to the structure of the organogold precursor. Mass spectral data obtained by LIMA indicate that the incorporation of the precursor and/or various photolysis byproducts into the deposit is related to the volatility of the ligand. Contamination is observed in tracks deposited from compounds containing the heavier ligand. Also, the electrical resistivities are correspondingly higher. Although isothermal annealing above 100 "C removes fragments containing the ligand, the resulting electrical conductivities are not improved.

Gold CVD Using Trifluorophosphine Gold(I) Chloride Precursor and Its Toluene Solutions

“…However, gold CVD studies have not been developed extensively like copper because of the limited gold precursor resource. Some recent studies showed that gold may be deposited from either gold͑I͒ precursors [3][4][5][6][7][8][9][10] or gold͑III͒ precursors. [11][12][13][14][15] Most of the known used precursors are metallo-organic compounds containing C or O atoms or both.…”

Reaction mechanism of the Me3AuPMe3–H2 plasma-enhanced ALD process

“…Davidson et al reported laser induced CVD of gold tracks using MeAuPMe 3 , MeAuPEt 3 , and EtAuPEt 3 using an argon ion laser at 257 nm. 9 The elemental composition and inclusion of precursor ligands on the surface was studied using laser ionization microprobe analysis. They observed the presence of chemisorbed PMe 3 species on the gold surface, which remained present on the surface for prolonged periods of time under high vacuum conditions.…”