Ampoule sealing apparatus and process
AssigneeThe United States of America as represented by the Administrator of the National Aeronautics and Space Administration
InventorsWilliam J. Debnam, Jr., Ivan O. Clark
Life of this patent
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Abstract
An apparatus 10 for effecting sealing of a fused quartz ampoule 24 while maintaining a vacuum on the ampoule via system 12 is disclosed. A plug 28 of fused quartz is lowered into the vertically disposed ampoule 24 (while maintaining the vacuum thereon) and heat sealed therein to prevent any vapor escape from, or contamination of, the contained semiconductor growth charge 29 during subsequent semiconductor crystal growth processes. A rotary vacuum feed-through mechanism 16 selectively rotates axle 34 and spool 32 to unwind wire 30 for lowering of plug 28 into the reduced diameter portion 24b of ampoule 24. Ampoule 24 is hermatically connected to vacuum housing 18 by quick release flange 20 wherein O-ring 22 retains ampoule 24.
Claims7
Means for precision sealing of an elongated ampoule and precision control of its contents after vacuum evacuation so as to achieve rapid production of precisely repeatable samples comprising in combination:
- an ampoule having contents to be utilized under sealed vacuum therein and having an open end for receiving these contents therein,
- said ampoule being provided with a first diameter portion at the open end thereof and a reduced diameter portion at the other end with the ampoule contents being disposed in the reduced diameter portion,
- means for retaining said ampoule in a vertical open end up position,
- means for evacuating said ampoule,
- plug means for sealing said ampoule,
- retention means for releasably maintaining said plug means adjacent the ampoule open end while said ampoule is evacuated,
- positioning means for inserting said plug means into said ampoule while the vacuum therein is retained,
- heat sealing means for sealing said plug in position in said ampoule,
- said ampoule and said plug means being constructed from fused quartz, and whereby the sealed ampoule is a homogeneous and continuous unit at the sealed portion thereof.
A method for evacuating and sealing a charged fused quartz ampoule after evacuation and while maintaining vacuum pressure on the ampoule comprising:
- providing a fused quartz ampoule having a sealed reduced diameter end portion and an open end enlarged diameter portion and having a charge disposed within the reduced diameter portion;
- maintaining the fused quartz ampoule in a vertical position with the open end thereof up;
- suspending a fused quartz plug having the same composition as the fused quartz ampoule for sealing the reduced diameter charged portion within and spaced on all sides from the open enlarged diameter portion;
- evacuating the ampoule and, while maintaining the vacuum,
- positioning the plug within the reduced diameter portion
- and heating the area of the ampoule containing the plug to the fusion or weld temperature of the ampoule and plug;
- and thereafter cooling the heated portion to ambient temperature to recover a sealed evacuated charged ampoule.
Dependencies are inferred from the claim text.