US2753458A - Electron microscope - Google Patents
Electron microscope Download PDFInfo
- Publication number
- US2753458A US2753458A US446126A US44612654A US2753458A US 2753458 A US2753458 A US 2753458A US 446126 A US446126 A US 446126A US 44612654 A US44612654 A US 44612654A US 2753458 A US2753458 A US 2753458A
- Authority
- US
- United States
- Prior art keywords
- specimen
- gas
- electron beam
- cylinder
- heating element
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000010438 heat treatment Methods 0.000 claims description 67
- 239000007789 gas Substances 0.000 description 37
- 238000010894 electron beam technology Methods 0.000 description 31
- 238000006243 chemical reaction Methods 0.000 description 7
- 238000004891 communication Methods 0.000 description 5
- 239000008187 granular material Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000012495 reaction gas Substances 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000012840 feeding operation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229910052573 porcelain Inorganic materials 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/02—Details
- H01J37/20—Means for supporting or positioning the object or the material; Means for adjusting diaphragms or lenses associated with the support
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/02—Details
- H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement or ion-optical arrangement
- H01J37/10—Lenses
- H01J37/12—Lenses electrostatic
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S164/00—Metal founding
- Y10S164/04—Dental
Definitions
- This invention relates to an electron microscope, and more particularly to an electron microscope in which changing conditions of a specimen which is continuously subjected to heating or gas reaction can be observed or photographed.
- This invention intends to remove the above troublesome handling and operation.
- the chief object of this invention is to provide an electron microscope in which changing conditions of a specimen which has been held in the passage of the electron beam during heating or gas reaction treatment can be observed or photographed.
- Another object of this invention is to provide an electron microscope which enables to observe changing conditions of the same region or the region adjacent thereto of a specimen being held in the same observation field.
- Further object of this invention is to provide an electron microscopic arrangement in which a heating element of the specimen and a gas feeding device can easily be attached to a ready made electron microscope, if needed.
- a heating element is entirely enclosed in a microscopic column and a specimen holder is combined with the heating element, a specimen being so attached thereto that it is held in the passage of the electron beam during the condition changing treatment.
- the heating element, as well as the specimen holder is associated with an adjusting means which can be operated out of the vacuum to set the specimen at any desired position. That is, the above arrangement is so made that continuous changing conditions of the specimen region laid in the same observation field can be investigated during heat treatment.
- Heat shielding means are provided for preventing the objective pole pieces which are to be positioned near by the specimen from being excessively heated.
- a cylinder which is transversely arranged with respect to the lens axis and into which the heatin" element and the specimen holder in tegrally and detachably fit through one end thereof, the upper and lower side walls of the cylinder forming little holes through which the electron beam can be passed.
- an auxiliary heat shielding plate which is disposed out of the cylinder and has a little hole just large enough to pass the electron beam therelhrough, for aiding prevention of overheating to the objeclive pole pieces.
- This shielding plate plays also the part of preventing granules which will fly in all directions from the specimen in operation from choking the holes of the objective pole pieces. if the hole of the shielding plate nite States Patent Eatented July 3, 1956 2 has been clogged with the granules to prevent the advance of the electron beam, this shielding plate can be substituted by a new one.
- the gas feeding means comprise a pipe inserted into the microscope from a gas source equipment which is arranged out of the vacuum and a nozzle connected to the pipe.
- a gas exhaust passage is also provided for removing the exhaust and excessive gases out of the column. This exhaust passage is composed of a connection pipe the inlet of which is near to the specimen position and an outlet tube secured to the column.
- the above mentioned cylinder can also be used as a member for enclosing the specimen so as to prevent the fed gas from diffusing all over the vacuum.
- the construction is such that the nozzle is opened into the cylinder from the other end opposite to the attaching end of the heating element and the same end of the cylinder is in communication with one end of a bellows, the other end thereof being connected to an outlet tube.
- the cylinder Above the cylinder is arranged a wall having a little electron beam passing hole so that the cylinder is enclosed in a narrow chamber formed between the objective pole pieces and the wall, the narrow chamber communicating with an exhaust pipe which is led to a vacuum pump.
- the vacuum in the column is scarcely reduced by gas leakage, although such gas leakage might be taking place through the electron beam passing hole formed in the cylinder wall.
- Adjusting means are also provided for adjusting the specimen to and fro and for inclining the same to the advance direction of the electron beam.
- the means are constructed to be operated manually out of the vacuum, the inner end thereof being connected to the heating element.
- the bellows connected to the cylinder enables to operate freely the specimen adjusting means.
- the specimen adjusting means can be constructed in any preferable manner, an example thereof will easily be understood from the detailed explanation hereinafter described referring to the accompanying drawing.
- Fig. l is a vertical sectional view of main parts of an electron microscope according to this invention, showing the relative arrangement of a specimen heating element and specimen adjusting means;
- Fig. 2 is a sectional view along the line A-A of Fig. 1, showing the relation between a specimen attached to a heating element and gas feeding means.
- 1 represents one column of a microscope forming a vacuum chamber 2 therein.
- 3 is a wall having an electron passing hole 4, which divides the column chamber into the vacuum chamber 2 and an upper vacuum chamber 5.
- An electron beam producing device will be arranged in the upper part of the column, but the explanation and illustration in connection therewith are omitted for the sake of simplicity, as this invention has no direct relation thereto.
- 6 is a pair of electron beam defleeting devices having coils 7 and iron cores 7 which latter are detachably inserted into the former.
- 8 is an objective lens and 9 its pole pieces having electron passing holes Ill in the centre thereof.
- a specimen heating element 11 which is composed of a heating body 12 as the axial part and an electric heater 13 Wound thereon, these parts being supported in a cylindrical insulator 14, made of porcelain, which has an arm 17 formed integrally therewith and extended perpendicularly thereto.
- a specimen holder 15 is secured to the heating body 12 or formed integrally therewith and a specimen 16 attached thereto is maintained in the position where it is exposed to the electron beam.
- the cylindrical insulator 14 is detachably fitted into a cylinder 37 which is arranged transversely to the lens axis. This cylinder serves as a heat shield which prevents overheatng of the objective pole pieces 9 by heat from the heating element.
- an auxiliary heat shielding plate 50 which prevents excessive heat from arriving at the objective pole pieces 9.
- the auxiliary shielding plate and the pole pieces are also provided with little holes 49 and respectively through which the electron beam can be passed.
- the heat proof arm 17 is secured to the inner end of an ax1s 18, the outer end of which is extended through the column.
- the axis 18 is inserted into and coaxially with a sleeve 19 and the outer end extended from the latter has a knob 20, the inner surface of which is rotatbly engaged with the outer head 21 of the sleeve 19.
- a nut 23 To a threaded neck 22 of the sleeve is screwed a nut 23, the inner face of which contacts the outer end of a guiding member 24 mounted on the column.
- a sliding member 25 is fitted into the guiding member 24 so as to be guided thereby in the direction perpendicular to the paper.
- pins 26 which mesh with longitudinal guiding slots 27 formed so as to guide the sleeve 19 along its axis only.
- the inner end of the sleeve 19 and the base of the guiding member 24 are connected by means of a bellows 28 which serves to hold the vacuum in the column and enables to operate freely the adjusting mechanism above ment1oned.
- 29 are the terminals of the electric heater; and 30 terminals of a thermo-couple 31 attached to the specimen holder 15. Lead wires 32 and 33 connected respectively to these terminals pass through the axis 18, led to the outside of the vacuum.
- the heating element accordingly the specimen position can be adjusted as follows:
- the inclined angle of the specimen to the advance direction of the electron beam can be adjusted by rotating the knob 2G.
- the sleeve 19 accompanied by the axis 18 slides along its axis by rotating the nut 23, so that the specimen can be displaced to the right and the left.
- the sleeve 19 is biased inwardly by elasticity of the bellows 28.
- any adequate adjusting mechanism for moving the sliding mernber 25 in the guiding member 24 will be also provided. Adjusting screws (not shown) may be used for pushing the sliding member 25 in the reverse direction.
- a gas feeding passage is preferably formed for supplying gas to the specimen surface being exposed to the electron beam. That is, the passage is so constructed that a flexible pipe 35 one end of which is in communication with any desired gas supply source 34 is led into the column therethrough and the other end of which is in communication with a nozzle 36 from which gas is supplied to the specimen surface.
- a connector is also provided for arranging the specimen 16 and the nozzle 36 in such relation that the fed gas is prevented from diffusing to all other vacuum chamber 3.
- the cylinder 37 serves also as such a connector in this example.
- the heating element 11 is detachably fitted to one end of the cylinder 37 as already described and to the other end thereof is secured a cover 38 through which the nozzle 36 is inserted.
- An exhaust passage is provided for removing exhaust and excessive gases out of the column, which passage has a bellows 43 formed as a connection pipe, the inlet of which is in communication with the cylinder 37, the other end of the bellows being in communication with an outlet tube 42 hermetically secured to the column wall. It is preferable to arrange the flexible pipe 35 in the bellows 43, one end of the flexible pipe communicating with a gas pipe 44 which is secured to the tube 42 and the other end thereof to the nozzle 36.
- the gas inlet pipe and outlet tube 42, with the bellows, to which one end of the cylinder 37 is previously attached, are secured to the column and thereafter the sleeve 19 accompanied by all parts associated therewith including the element 11 is inserted through the column to fit the heating element into the other end of the cylinder 37.
- the cylinder 37 can be freely moved owing to flexibility of the pipe 35 and elasticity of the bellows 23 and 43.
- a wall 45 in the vacuum chamber 2 to form a comparatively narrow chamber 46 which contains the cylinder 37, the chamber thus formed being continuously vacuumed through a vacuum pipe 47 communicating therewith.
- the auxiliary heat shielding plate 54 also serves to prevent granules which will fly in all directions from the specimen in operation from arriving at the holes 10 of the objective pole pieces 9. According to the inventors experiments, it was found that reaction gas which is fed into the vacuum chamber neither substantially prevents the advance of the electron beam nor influences upon the vacuum. However, in consideration of fear of preventing the advance of the electron beam according to kind of gas or its thickness, it will be preferable to carry out the gas feeding operation from the nozzle intermittently.
- changing conditions of the same region or the region adjacent thereto of a specimen which is subjected to heating and gas reaction can be continuously observed or photographed in the same observation field.
- a lens system comprising a plurality of lenses and observation and photographing parts which are to be arranged under the objective lens is well known by those skilled in the art, so that explanation and illustration in connection with these well known parts are omitted for the sake of simplicity.
- An electron microscope comprising in combination heating means which are arranged in the column of a microscope for heating a specimen, a specimen holder for holding said specimen in the passage of the electron beam during heat treatment and heat shielding means located adjacent said heating means for preventing objective pole pieces from being overheated by said heating means, thereby enabling that continuous heating conditions of said specimen is observed.
- An electron microscope comprising in combination a heating element having a heating body and an electric heater Wound thereon which are arranged in the column of a microscope, a specimen holder which is secured to said heating body for holding a specimen in the passage of electron beam during heat treatment, and a heat shielding member which is disposed between said heating element and objective pole pieces for preventing said objective pole pieces from being overheated by said heating element.
- An electron microscope comprising in combination a heating element having a heating body and an electric heater wound thereon which are arranged slightly above on objective pole pieces, a specimen holder Which is formed integrally with said heating body for holding a specimen in the passage of the electron beam during heat treatment, and a heat shielding cylinder which is arranged transversely to the lens axis and which surrounds said heating element and said specimen holder, for preventing objective pole pieces from being overheated by said heating element, said heat shielding cylinder having little holes just large enough to pass the electron beam.
- An electron microscope comprising in combination a heating element having a heating body and an electric heater wound thereon which are arranged slightly above the objective pole pieces, a specimen holder which is formed integrally with said heating body for holding a specimen in the passage of the electron beam during heat treatment, a heat shielding cylinder which is arranged transversely to the lens axis and which surrounds said heating element and said specimen holder, said heat shielding cylinder having little holes just enough to pass the electron beam, a heat proof arm attached to said heat element, and adjusting means which is connected to said heat proof arm for adjusting the position of said specimen from the outside of the microscopic column.
- An electron microscope comprising in combination a heating element having a heating body and an electric heater wound thereon which are arranged slightly above the objective pole pieces, a specimen holder which is formed integrally with said heating body for holding a specimen in the passage of the electron beam during heat treatment under gas feeding, a heat shielding cylinder which is arranged transversely to the lens axis and in which said heating element with said specimen holder is enclosed through one end thereof, said heat shielding cylinder having little holes just large enough to pass the electron beam, a gas feeding device for introducing reaction gas into said heat shielding cylinder through a cover attached to the other end thereof, thereby preventing said objective pole pieces from being overheated by said heat element and simultaneously preventing reaction gas from diffusing through said little holes out of said heat shielding cylinder, and a gas exhaust passage communicated with said heat shielding cylinder for leading out exhaust and excessive gases.
- An electron microscope comprising in combination a heating element having a heating body and an electric heater wound thereon which are arranged slightly above the objective pole pieces, a specimen holder which is formed integrally with said heating body for holding a specimen in the passage of the electron beam during heat treatment, a heat shielding cylinder which is arranged transversely to the lens axis and which surrounds said heating element and said specimen holder for preventing objective pole pieces from being overheated by said heating element, said heat shielding cylinder having little holes just large enough to pass the electron beam, and an auxiliary shielding plate which is disposed between said heat shielding cylinder and said objective pole pieces for reducing heating of said objective pole pieces by said heating element and further serving to prevent granules which will fly in all directions from said specimen under treatment from arriving at holes of said objective pole pieces, said auxiliary heat shielding plate having a little hole just large enough to pass the electron beam.
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Analysing Materials By The Use Of Radiation (AREA)
- Sampling And Sample Adjustment (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP325279X | 1954-04-12 |
Publications (1)
Publication Number | Publication Date |
---|---|
US2753458A true US2753458A (en) | 1956-07-03 |
Family
ID=12361421
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US446126A Expired - Lifetime US2753458A (en) | 1954-04-12 | 1954-07-27 | Electron microscope |
Country Status (5)
Country | Link |
---|---|
US (1) | US2753458A (fr) |
CH (1) | CH325279A (fr) |
DE (1) | DE1039153B (fr) |
FR (1) | FR1113365A (fr) |
GB (1) | GB772621A (fr) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3051834A (en) * | 1959-09-16 | 1962-08-28 | Shimula Yoshihiro | Automatic recording system of x-ray diffraction patterns |
US3171958A (en) * | 1962-03-30 | 1965-03-02 | Rca Corp | Heated specimen holder for the electron microscope |
US3257554A (en) * | 1962-08-28 | 1966-06-21 | Ass Elect Ind | Electron microscope specimen holder having means for heating the specimen |
US3290119A (en) * | 1959-05-14 | 1966-12-06 | Nuclear Technical Services Cor | Inspection unit |
US3313936A (en) * | 1964-01-06 | 1967-04-11 | Varian Associates | Low energy electron diffraction apparatus having three concentric tubular focusing elctrodes |
US3327114A (en) * | 1964-06-23 | 1967-06-20 | Alfred F Diorio | Low-angle x-ray diffraction camera comprising releasably connected sections and adjustable beam apertures and stops |
US3896314A (en) * | 1972-12-14 | 1975-07-22 | Jeol Ltd | Specimen heating and positioning device for an electron microscope |
US4071766A (en) * | 1974-03-28 | 1978-01-31 | Mta Kozponti Kemiai Kutato Intezet | Micro-chamber for electron optical examinations particularly for the electron microscopic examination of biological objects |
US4142088A (en) * | 1973-08-17 | 1979-02-27 | The United States Of America As Represented By The United States Department Of Energy | Method of mounting a fuel pellet in a laser-excited fusion reactor |
US5296669A (en) * | 1992-05-29 | 1994-03-22 | Hitachi, Ltd. | Specimen heating device for use with an electron microscope |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2266082A (en) * | 1938-05-02 | 1941-12-16 | Fides Gmbh | Electron microscope |
US2417213A (en) * | 1944-12-28 | 1947-03-11 | Rca Corp | Device for indirect heating of materials |
US2467225A (en) * | 1948-05-22 | 1949-04-12 | Rca Corp | Reducing specimen contamination in electron optical instruments |
US2467224A (en) * | 1948-02-21 | 1949-04-12 | Rca Corp | Neutralization of electrostatic charges in electron-optical instruments |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE659092C (de) * | 1934-12-12 | 1938-04-25 | Ernst Ruska Dr Ing | Einschleusvorrichtung fuer an der Pumpe betriebene Korpuskularstrahlapparate |
CH240304A (de) * | 1941-12-03 | 1945-12-15 | Ardenne Manfred Von | Heizbarer Objektträger an einem Elektronenstrahlgerät. |
CH233969A (de) * | 1942-04-29 | 1944-08-31 | Fides Gmbh | Korpuskularstrahlapparat. |
DE888896C (de) * | 1943-08-03 | 1953-09-07 | Siemens Ag | Elektrisch heizbarer Objekttraeger fuer Elektronenstrahlgeraete |
-
1954
- 1954-07-27 US US446126A patent/US2753458A/en not_active Expired - Lifetime
- 1954-08-04 GB GB22694/54A patent/GB772621A/en not_active Expired
- 1954-09-04 CH CH325279D patent/CH325279A/de unknown
- 1954-10-06 FR FR1113365D patent/FR1113365A/fr not_active Expired
- 1954-10-16 DE DEK23753A patent/DE1039153B/de active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2266082A (en) * | 1938-05-02 | 1941-12-16 | Fides Gmbh | Electron microscope |
US2417213A (en) * | 1944-12-28 | 1947-03-11 | Rca Corp | Device for indirect heating of materials |
US2467224A (en) * | 1948-02-21 | 1949-04-12 | Rca Corp | Neutralization of electrostatic charges in electron-optical instruments |
US2467225A (en) * | 1948-05-22 | 1949-04-12 | Rca Corp | Reducing specimen contamination in electron optical instruments |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3290119A (en) * | 1959-05-14 | 1966-12-06 | Nuclear Technical Services Cor | Inspection unit |
US3051834A (en) * | 1959-09-16 | 1962-08-28 | Shimula Yoshihiro | Automatic recording system of x-ray diffraction patterns |
US3171958A (en) * | 1962-03-30 | 1965-03-02 | Rca Corp | Heated specimen holder for the electron microscope |
US3257554A (en) * | 1962-08-28 | 1966-06-21 | Ass Elect Ind | Electron microscope specimen holder having means for heating the specimen |
US3313936A (en) * | 1964-01-06 | 1967-04-11 | Varian Associates | Low energy electron diffraction apparatus having three concentric tubular focusing elctrodes |
US3327114A (en) * | 1964-06-23 | 1967-06-20 | Alfred F Diorio | Low-angle x-ray diffraction camera comprising releasably connected sections and adjustable beam apertures and stops |
US3896314A (en) * | 1972-12-14 | 1975-07-22 | Jeol Ltd | Specimen heating and positioning device for an electron microscope |
US4142088A (en) * | 1973-08-17 | 1979-02-27 | The United States Of America As Represented By The United States Department Of Energy | Method of mounting a fuel pellet in a laser-excited fusion reactor |
US4071766A (en) * | 1974-03-28 | 1978-01-31 | Mta Kozponti Kemiai Kutato Intezet | Micro-chamber for electron optical examinations particularly for the electron microscopic examination of biological objects |
US5296669A (en) * | 1992-05-29 | 1994-03-22 | Hitachi, Ltd. | Specimen heating device for use with an electron microscope |
Also Published As
Publication number | Publication date |
---|---|
FR1113365A (fr) | 1956-03-28 |
CH325279A (de) | 1957-10-31 |
GB772621A (en) | 1957-04-17 |
DE1039153B (de) | 1958-09-18 |
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