Deposition of Platinum from Bis(Acetylacetonato)Platinum(II)

Abstract

The evaporation and deposition process of Bis(acetylacetonato)platinurn(LI) fPt(acac)J was examined in a computerized microbalance system, which allows the measuring of the mass of evaporating precursor and depositing layer simultaneously. The investigations were carried out in an argon-atmosphere and an argonloxygen-atmosphere with pressure ranging from 250 Pa to 1000 Pa. The deposition kinetics were investigated in the temperature range between Tdep = 523 K and Tdep= 733 K. A strong dependence of the deposition rate on the pretreatment of the substrate was observed. Beginning the deposition on alumina with low deposition temperatures Tdep an activation energy of 204 + 9 Mlmol was found. On platinum precoated substrates we observed higher deposition rates and lower values for the activation energy, if the precoating was carried out at temperature T w > Tdcp. At long deposition tirnes with Tdep= const. the deposition rates on precoated substrates decreased to the values obtained without precoating at higher temperatures. This effect has not been clarified. In argon-atmosphere platinum layers containing carbon were deposited. Increasing the deposition temperature caused increased carbon contamination. The carbon can be removed by oxidation in air after the deposition. Platinum coatings without carbon contamination were obtained by adding oxygen during the deposition process.

Metal Organic CVD of Nanostructured Composite TiO 2 ‐Pt Thin Films: A Kinetic Approach

“…In many cases platinum films have contained a very high carbon concentration, [6] which can be drastically reduced by carrying out the deposition either in oxygen or in hydrogen atmospheres. [7] From such literature data, Pt(acac) 2 seems suitable for use in a co-deposition process together with TTIP, as the reported growth conditions are similar to those we found for TiO 2 .…”

“…Platinum thin film growth has already been studied using Pt(acac) 2 as precursor in an oxygen-free environment in the temperature range 523±733 K, [7] where the resulting deposition process was kinetically controlled; however, on adding oxygen during the deposition process, the resulting film growth was independent of reactor temperatures higher than 520 K. In this paper we report the deposition of platinum films on glass, stainless steel, platinum, and TiO 2 films at 80 Pa and varying reactor temperature in the range 653±693 K and varying sublimation temperature of Pt(acac) 2 in the range 390±450 K. The molar ratio oxygen/precursor at the inlet was in the 20±130 range. Figure 2 (curve a) shows the temperature dependence of the deposition rate: the growth rate is independent of deposition temperatures above 668 K, indicating a diffusion-limited deposition process.…”

Chemical Vapor Deposition of Iridium, Platinum, Rhodium and Palladium

“…A different activation energy value about 56 kJÁmol À1 , was determined for the deposition on a platinum pre-coated substrate. 45) Under similar argon atmosphere conditions, consistent activation energies for a reaction-controlled regime about 200 kJÁmol À1 at temperatures below 743 K and for a diffusion-controlled regime about 60 kJÁmol À1 at higher temperatures were calculated. 20) The study of the rate-limited mechanisms in CVD may allow an appropriate selection of the deposition temperature needed to obtain high deposition rates.…”

MOCVD of Platinum (100) Films on Random Hastelloy C276

“…[13] Lower temperatures and argon-oxygen atmosphere have proven to produce carbon-free platinum layers. [15,16] In this communication, we report on the deposition of (100)-oriented platinum films on Hastelloy C276 (Hast) from Pt(acac) 2 . To our knowledge, this represents the first report of (100)-oriented platinum films obtained using MOCVD on a non-epitaxial substrate.…”

“…The present experimental assembly, at variance with that adopted in other studies, [16] allows deposition at temperatures as low as 200 C. The source sublimation temperature was kept constant at 170 C in all experiments, while substrate temperatures were explored in a wide range (200±500 C). The lower temperatures (< 260 C) were not sufficient to thermally activate the precursor decomposition.…”