Patent Number: 042726824
Section: claims

1. A machine for ion milling a specimen comprising: a main evacuated chamber having an upper port and a lower port;  ion milling means for ion milling of a specimen disposed in said main evacuated chamber;  a secondary chamber in communication with said main chamber through its upper port for specimen viewing and exchange;  specimen positioning means extending through said lower port of said main chamber for vertically moving the specimen between a first position in said main evacuated chamber, where ion thinning is accomplished, and a second position in said secondary chamber, where the specimen can be viewed and exchanged;  means for sealing said main chamber at its lower port; and  sealing means for providing a vacuum seal between said main chamber and said secondary chamber when said specimen positioning means is in the second position.  said secondary chamber is removable from said main chamber; and,  said secondary chamber is held to said main chamber by atmospheric pressure when said main chamber and said secondary chamber are evacuated.  a transparent outer portion disposed so the specimen can be viewed when said specimen positioning means is in the second position.  vacuum valve means for connecting a vacuum to said secondary chamber; and  atmospheric valve means for connecting said secondary chamber to atmosphere.  drive means for rotating said specimen positioning means when said specimen positioning means is in the first position.  said specimen positioning means comprises an elongated piston extending into said main evacuated chamber and being movable along its longitudinal axis;  said sealing means at said lower port of said main chamber includes a seal around said elongated piston where it extends into said main evacuated chamber; and,  said drive means comprises:  a positioning cylinder disposed around a portion of said elongated piston outside of said main evacuated chamber;  a sealing plate providing a seal between said elongated piston and said positioning cylinder; and  the means for admitting or exhausting pressurized gas from the positioning cylinder for causing movement of said piston along its longitudinal axis.  a main chamber wherein ion thinning of the specimen is accomplished under vacuum;  a specimen elevating means for moving the specimen between a lowered position where ion thinning is accomplished and a raised position where the specimen can be viewed;  said specimen elevating means comprising,  a secondary chamber for receiving said specimen when said specimen elevating means is in its raised position; and  sealing means for sealing said secondary chamber from said main chamber when said specimen elevating means is in said raised position.  drive means for rotating said piston when said specimen elevating means is in its lowered position.  said specimen elevating means moves vertically and comprises a holder platform disposed for horizontally supporting a specimen so that the specimen can be held in place by the force of gravity.  a main evacuated chamber having an upper port and a lower port;  ion milling means for milling a specimen disposed in said main evacuated chamber;  a secondary chamber in communication with said main chamber through its upper port;  specimen support means extending into said main evacuated chamber through its lower port for supporting a specimen and being movable between a first position wherein said specimen is in said main chamber in position for ion milling and a second position wherein said specimen is in the secondary chamber;  means for sealing said main chamber where said specimen support means extends through said lower port of said main chamber;  sealing means for sealing said secondary chamber from said main chamber when said specimen support means moves the specimen into the secondary chamber; and  drive means for rotating the specimen when said specimen support means is in the first position.  atmospheric biasing means for biasing said specimen support means to the second position by atmospheric pressure;  pressurized gas biasing means for biasing said specimen support means to the first position by utilizing pressurized gas; and  release means for controllably releasing the pressurized gas from said pressurized gas biasing means to permit said specimen support means to move to the second position under the influence of atmospheric pressure.  a specimen inspection chamber in communication with said main chamber;  means for supporting said specimen within said main chamber in a first position during said ion milling and for transporting said specimen to a second position within said inspection chamber;  means for sealing said main chamber from said inspection chamber when said specimen supporting and transporting means moves said specimen into said second position;  means for biasing said specimen supporting and transporting means toward said second position by the selected application thereto of atmospheric pressure; and  means for overcoming said biasing means by the selected application of superatmospheric pressure to said specimen supporting and transporting means to urge it into said first specimen position.  said specimen inspection chamber is releasably connected to said main chamber, when said specimen is in said second position, by the selective application of atmospheric or subatmospheric pressure to the interior of said inspection chamber.  a main chamber wherein ion thinning is accomplished under vacuum;  a specimen elevating means for moving the specimen between a lowered position where ion thinning is accomplished and a raised position where the specimen can be exchanged;  said specimen elevating means comprising:  a secondary chamber for housing said specimen when said specimen elevating means is in its raised position; and  sealing means for sealing said secondary chamber from said main chamber when said specimen elevating means is in said raised position. 2. A machine as claimed in claim 1 wherein: 3. A machine as claimed in claim 2 wherein said secondary chamber comprises: 4. A machine as claimed in claim 1 which further comprises: 5. A machine as claimed in claim 1 which further comprises: 6. A machine as claimed in claim 5 wherein: 7. A machine as claimed in claim 6 wherein said specimen positioning means further comprises: 8. A machine as claimed in claim 7 wherein said piston is oriented vertically. 9. An ion milling machine for ion thinning a specimen comprising: 10. An ion milling machine as claimed in claim 9 comprising: 11. An ion milling machine as claimed in claim 10 comprising: 12. An ion milling machine as claimed in claim 9 wherein: 13. An ion milling machine comprising: 14. An ion milling machine as claimed in claim 13 comprising: 15. In an ion milling machine having a main chamber in which ion milling of a specimen disposed therein is carried out under subatmospheric pressure, the improvement comprising: 16. The improvement recited in claim 15 wherein: 17. An ion milling machine for ion thinning a specimen comprising: