Stability Study of a Magnesium β-Diketonate As Precursor for Chemical Vapor Deposition of MgO

Abstract

On the basis of the study of the thermal behavior of [Mg(tmhd)2(TMEDA)] (1; tmhd =2,2,6,6-tetramethyl-3,5-heptanedionate; TMEDA = N,N,N′,N′-tetramethylethylenediamine), a novel procedure for magnesium oxide thin film growth has been developed for chemical vapor deposition (CVD) applications. Complementary studies (thermogravimetric measurements and IR and NMR spectroscopy) enabled revelation of the dissociation of TMEDA from 1, confirmed by the detection of both free TMEDA in the vapor phase and less volatile [Mg2(tmhd)4] (2) as a residue after sublimation. The effect of this dissociation is an unwanted changeable sublimation rate of the precursor 1 during the CVD process. The endeavor of a constant deposition rate by simultaneously exploiting the good volatility of 1 was achieved through its synthesis in situ by using 2 with a diamine enriched carrier. Laser reflectance interferometry (LRI) measurements testified that such a method ensured a good and constant deposition rate throughout the growth experiment, independently of the adopted processing conditions. In addition, X-ray diffraction (XRD) measurements revealed the obtainment of textured and polycrystalline MgO coatings on sapphire and on Si(100). The system chemical composition was investigated by X-ray photoelectron spectroscopy (XPS).

Zirconocene Alkoxides, Promising Precursors for MOCVD of Zirconium Dioxide Thin Films

“…A KLA‐Tencor Alpha‐Step IQ surface profiler was used to analyze the film height steps on partially masked samples after the deposition, while LRI, a convenient method to monitor the film growth in‐situ, allowed us to obtain real‐time information on the deposition process. Interferometer results were calculated according to the equation described elsewhere 55 (with zirconia refraction index = 2.13–2.20) 56.…”

A Study on Sc2O3‐Stabilized Zirconia Obtained by MOCVD as a Potential Electrolyte for Solid Oxide Fuel Cells

“…The LRI measurements allowed a non invasive in‐situ monitoring of the film growth on Si(100) by analyzing the number of fringes in the resulting interferogram. Interferometer results were calculated according to the equation described elsewhere 48 (with experimentally calculated refraction indexes of 2.24 and 2.14 for ScSZ and YSZ, respectively).…”

Magnesium β-ketoiminates as CVD precursors for MgO formation

“…1, the Mg(II) ion is hexa-coordinated by two tridentate b-ketoiminato ligands occupying meridional sides and a distorted octahedral MgN 2 O 6 coordination geometry in the OC-6-33 form. Deviations from the idealized octahedral geometry are observed, for example, the bond angles of transand cis-bonded donor atoms range from 164.87(8) to 165.4 (3) and 76.8(3) to 104.2 (8) , respectively (Fig. 1).…”

“…3 These groups are able to occupy an additional coordination site on the alkaline earth metals leading to less oligomerization of the molecules and thus increase the volatility of the complexes. In this respect, Rees and co-workers reported on the synthesis of the rst example of such a metal-organic species, bis[5-N-(N,N-dimethylaminopropyl)-2,2,7-trimethyl-3-octanonato]magnesium, 28 which successfully could be applied as precursor in the CVD process for MgO thin layer formation.…”