Patent Number: 047059494
Section: claims

1. An improved specimen cell for use in the evacuated chamber of a directed beam irradiation device having an electron beam, said cell comprising: means for preventing dehydration and disruption of a specimen placed in the cell including closed specimen means for mounting and at least partially containing said specimen;  means for defining a single aperture between said specimen and said electron beam when said beam is directed towards said speciman, said aperture comprising a means, sized and gometrically configured, for bidirectionally passing electrons and for restricting passage of vapor from within to without said specimen means; and  door means mounted on a pivotable arm for movement between an opened position and a closed position, for permitting bidirectional electron flow in said open position and for blocking said single aperture and for preventing passage of vapor from within to without said specimen means in said closed position, said door means comprising a backing metal plate attached to said arm and a facing of elastomeric material for blocking said aperture.  providing a closed specimen means, in said vacuum chamber, for mounting and at least partially containing said specimen where said closed specimen means includes means for defining an aperture between said specimen and said electron beam when said beam is directed towards said specimen, wherein said aperture comprises means for bidirectionally passing electrons and for restricting passage of vapor from within to without said specimen means;  providing a door means having an open position and a closed position;  locating a specimen in the specimen means and closing said door means;  reducing the pressure in the evaucated chamber to the normal electron microscope operating pressure while maintaining the door means in said closed position;  moving said door means to said open position; and  scanning said specimen with said electron beam through said aperture.  closing said door means after said scanning to prevent further passage of vapor from within to without said specimen means; and  repeating said opening, scanning, and closing steps for further scanning of said specimen.  a sole means for preventing dehydration and disruption of a specimen placed in the cell including closed specimen means for mounting and at least partially containing said specimen;  means for defining a single aperture between said specimen and said electron beam when said beam is directed towards said specimen, said sperture comprising a means, sized an geometrically configured, for bidirectionally passing electrons and for restricting passage of vapor from within to without said specimen means; and  door means, mounted in a pivotable arm for movement between an opened position and a closed position for permitting bidirectional electron flow in said open position and for blocking said single aperture and for preventing passage of vapor from within to without said specimen means in said closed position said door means comprising a backing metal plate attached to said arm and a facing of elastomeric material for blocking said aperture. 2. The specimen cell according to claim 1, wherein said specimen means comprises a closed specimen module. 3. The specimen cell according to claim 1, wherein said specimen means comprises a specimen cell body and an open specimen module. 4. The specimen cell according to claim 2, wherein said closed specimen module comprises an upper portion and a lower portion and said means for defining a single aperture comprises a single aperture in said upper portion. 5. The specimen cell according to claim 3, wherein said open specimen module includes an upper chamber lid and a mesh specimen mounting means located thereunder. 6. The specimen cell according to claim 5, wherein said open specimen module further includes a liquid/gas induction shroud surrounding said mesh means. 7. The specimen cell according to claim 6, wherein said open specimen module further includes sealing means for sealing said chamber lid to said specimen cell body. 8. The specimen cell according to claim 1, wherein said aperture has a diameter within the range of from 200 angstroms to 500 microns. 9. The specimen cell according to claim 8, wherein said aperture diameter is substantially equal to 200 microns. 10. The specimen cell according to claim 3, wherein said cell body includes a means for heating said open specimen module. 11. The specimen cell according to claim 3, wherein said cell body includes a means for cooling said open specimen module. 12. The specimen cell according to claim 3, wherein said cell body includes a means for injecting a fluid into said open specimen module. 13. The specimen cell according to claim 3, wherein said specimen cell body includes upper, middle, and lower portions with said upper and middle portions separated by a diaphragm and further including means for introducing a fluid into said middle portion forcing said diaphragm to move towards said upper portion. 14. The specimen cell according to claim 13, wherein said means for introducing a fluid includes a means for modulating said fluid for causing said diaphragm to vibrate. 15. The specimen cell according to claim 2, wherein said cell body includes a means for heating said closed specimen module. 16. The specimen cell according to claim 2, wherein said cell body includes a means for cooling said closed specimen module. 17. A method of exposing a specimen to the electron beam of a directed beam irradiation device in a vacuum chamber without destroying high vapor pressure specimens, said method comprising: 18. The method according to claim 17, further including after said scanning step the additional steps of: 19. An improved specimen cell for use in the evacuated chamger of a directed beam irradiation device having an electron beam, said cell comprising: