Process for the preparation of magnesium oxide films using organ

Details Process for the preparation of magnesium oxide films using organ Process for the preparation of magnesium oxide films using organ

1997-12-18

1999-09-21

Beck, Shrive

Coating processes

Coating by vapor, gas, or smoke

Mixture of vapors or gases utilized

427226, 117944, C23C 1600

Patent

active

059551461

DESCRIPTION:

BRIEF SUMMARY
FIELD OF THE INVENTION

The present invention relates to a process for coating a substrate with a magnesium oxide film using an organomagnesium compound having an oxygen to magnesium atomic ratio of 1:1.


BACKGROUND OF THE INVENTION

Magnesium oxide is a transparent and chemically stable material having good electric insulation property and it does not undergo a phase transition even at a high temperature up to its melting temperature of 2852.degree. C. Magnesium oxide has been used as a substrate for preparing thereon films of a number of inorganic compounds, i.e., various oxides such as cuprate-based high-T.sub.c superconductors, lithium niobate, barium titanate, and nitrides such as gallium nitride, niobium nitride, and the like.
Although large single crystals having uniform properties have been successfully grown for quartz, silicon, gallium arsenide(GaAs), sapphire and the like, a process for preparing large single crystals of high-temperature superconductors has not yet been developed. Also, attempts to prepare a high-temperature superconducting film directly on the surface of quartz, silicon, gallium arsenide or sapphire crystal have not been-successful. However, it is known that a high-temperature superconductor film having excellent property can be prepared via coating a magnesium oxide film on the surface of a single crystal substrate. For example, a copper oxide high-temperature superconductor may be deposited and grown on a magnesium oxide film coated on the surface of a silicon single crystal (D. K. Fork, F. A. Ponce, J. C. Tramontana, and T. H. Geballe, Applied Physics Letters, 58, 2294 (1991)). It is also known that magnesium oxide can be used as a diffusion barrier which inhibits the reaction between silicon and barium titanate, and the resulting dielectric material may find use in semiconductor memory devices of the next generation.
Hitherto, there have been reported a number of chemical vapor deposition(CVD) methods for the preparation of a magnesium oxide film at a relatively low temperature.
For example, Kwak et al. reported that a crystalline film of magnesium oxide may be prepared on the surface of a silicon single crystal or quartz by heating bis(2,2,6,6-tetramethyl-3,5-heptanedionato)magnesium of formula 1 to 196.degree. C. and carrying the vapor thereof in an argon stream containing oxygen to the substrate heated above 650.degree. C. (B. S. Kwak, E. P. Boyd, K. Zhang, A. Erbil, and B. Wilkins, Applied Physics Letters, 54, 2542 (1989)). ##STR1##
Lu et al. disclosed that a crystalline film of magnesium oxide can be prepared on the surface of sapphire or strontium titanate at a temperature below 600.degree. C. by carrying bis(2,2,6,6-tetramethyl-3,5-heptanedionato)magnesium in a helium or argon stream to the substrate and then adding oxygen thereto (Z. Lu, R. S. Feigelson, R. K. Route, S. A. DiCarolis, R. Hiskes, and R. D. Jacowitz, Journal of Crystal Growth, 128, 788 (1993)).
Using a plasma-assisted chemical vapor deposition method, Zhao and Suhr prepared crystalline magnesium oxide films on the surfaces of glass, quartz, silicon single crystal and stainless steel by carrying bis(2,2,6,6-tetramethyl-3,5-heptanedionato)magnesium heated at 200.degree. C. in argon stream to the substrate heated above 400.degree. C. and adding oxygen thereto (Y. W. Zhao and H. Suhr, Applied Physics A, 54, 451 (1992)).
Maruyama et al., on the other hand, reported that a crystalline magnesium oxide film may be formed on the surface of glass, quartz or silicon single crystal by treating the substrate heated above 450.degree. C. with an air stream containing magnesium 2-ethylhexanoate of formula 2 (T. Maruyama and J. Shionoya, Japanese Journal of Applied Physics, 29, L810 (1990)). It was reported therein that a magnesium oxide film did not form when the carrier gas was nitrogen instead of air. ##STR2##
According to DeSisto and Henry, an amorphous magnesium oxide film was deposited on the surface of a silicon single crystal, quartz or sapphire by ultrasonic spraying of an ##STR3## aqueous or alcoholic soluti

REFERENCES:
patent: 4382980 (1983-05-01), Donohue
patent: 5258204 (1993-11-01), Wernberg et al.
patent: 5656329 (1997-08-01), Hampden-Smith et al.
Ashby et al., A New Convenient, and Stereospecific Method for the Dehydration of Alcohols. The Thermal Decomposition of Magnesium, Zinc, and Aluminum Alkoxides. A Mechanistic Study, J. Org. Chem., vol. 44, No. 8, pp. 1221-1232, Aug. 1979.

Affiliated with

Also associated with

Rating

Process for the preparation of magnesium oxide films using organ does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for the preparation of magnesium oxide films using organ, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the preparation of magnesium oxide films using organ will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-78050