Coating apparatus – Control means responsive to a randomly occurring sensed... – Condition of coated material
Reexamination Certificate
2001-07-30
2003-01-28
Bueker, Richard (Department: 1763)
Coating apparatus
Control means responsive to a randomly occurring sensed...
Condition of coated material
C118S668000, C118S669000, C118S697000, C118S729000
Reexamination Certificate
active
06511544
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention was made with Government support under Contract No. DE-AC05-96OR22464 awarded by the U.S. Department of Energy to Lockheed Martin Energy Research Corporation, and the Government has certain rights in the invention.
This invention relates generally to the growth of thin-films upon semiconductor-based materials and relates, more particularly, to the means and methods by which the growth of such thin-films in a high vacuum facility can be controlled.
The growth of thin-films in a high vacuum facility may be monitored with Reflection High Energy Electron Diffraction (RHEED) techniques involving the use of a high energy electron beam emitted from an electron gun to diffract electrons off of a substrate (i.e. target) surface at a glancing angle. These diffracted electrons are diffracted in a pattern which provides crystallographic information of the film surface. More specifically, each crystallographic condition of the film surface evidences a signature electron diffraction pattern so that during a thin-film growth process, a desired crystallographic condition of the film surface can be substantiated by an electron diffraction pattern which is indicative of the desired crystallographic condition.
However, to obtain desired RHEED measurements by conventional techniques, the substrate upon which the thin film is grown is rigidly mounted within the high vacuum facility and must typically, on occasion, by physically adjusted in position relative to the electron gun. Of course, in order to make adjustments in the position of the substrate, the film growth process must be halted and the facility may even have to be opened to gain access to the substrate. It follows that this conventional technique is time-consuming and is not well-suited for mass production techniques.
An object of the present invention is to provide a new and improved process and system for use during the growth enabling the film growth process to be efficiently controlled.
Another object of the present invention is to provide such a process which is well-suited for mass production techniques.
Still another object of the present invention is to provide such a process which is uncomplicated to perform yet effective in operation.
SUMMARY OF THE INVENTION
This invention resides in a process for growing a thin film upon the surface of a substrate involving the exposure of the substrate surface to vaporized material in a high vacuum (HV) facility and an associated system.
Within the process of the invention, the improvement comprises the steps of directing an electron beam generally toward the surface of the substrate as the substrate is exposed to vaporized material so that electrons are diffracted from the substrate surface by the beam and monitoring the pattern of electrons diffracted from the substrate surface as vaporized material settles upon the substrate surface. The improvement further includes the step of shutting off or otherwise adjusting the exposure of the substrate to the vaporized materials when the monitored pattern achieves a condition indicative of the desired condition of the thin film being grown upon the substrate.
A system of the invention includes means mounted within the HV facility for directing an electron beam generally toward the surface of the substrate so that electrons are diffracted from the substrate surface and means mounted within the HV facility for monitoring the pattern of electrons diffracted from the substrate surface. The system also includes means connected between the substrate and the directing means for moving the substrate and the directing means relative to one another to facilitate an adjustment of the crystallographic orientation of the thin film being grown upon the substrate surface relative to the directed electron beam.
REFERENCES:
patent: 4710259 (1987-12-01), Howe
patent: 4855013 (1989-08-01), Ohta
patent: 4962057 (1990-10-01), Epler
patent: 5120393 (1992-06-01), Kubo
patent: 5148025 (1992-09-01), Ahn
patent: 5225031 (1993-07-01), McKee et al.
patent: 5450812 (1995-09-01), McKee et al.
patent: 5554415 (1996-09-01), Turchan
patent: 5588995 (1996-12-01), Sheldon
patent: 5588999 (1996-12-01), Takahashi
patent: 5691280 (1997-11-01), Eckstein et al.
patent: 5827802 (1998-10-01), Lagues
patent: 5919515 (1999-07-01), Yano
patent: 6121647 (2000-09-01), Yano
McKee Rodney A.
Walker Frederick J.
Bueker Richard
McKee Michael E.
UT-Battelle LLC
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