JPH09196831A - Specimen cooling and observing device - Google Patents
Specimen cooling and observing deviceInfo
- Publication number
- JPH09196831A JPH09196831A JP8007095A JP709596A JPH09196831A JP H09196831 A JPH09196831 A JP H09196831A JP 8007095 A JP8007095 A JP 8007095A JP 709596 A JP709596 A JP 709596A JP H09196831 A JPH09196831 A JP H09196831A
- Authority
- JP
- Japan
- Prior art keywords
- sample
- specimen
- heating
- heating element
- cooling
- 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.)
- Pending
Links
Landscapes
- Sampling And Sample Adjustment (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、走査形電子顕微鏡
及びその類似装置に係り、特に走査形電子顕微鏡に使用
するに好適な試料冷却観察装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning electron microscope and an apparatus similar thereto, and more particularly to a sample cooling observation apparatus suitable for use in a scanning electron microscope.
【０００２】[0002]
【従来の技術】試料に収束電子線を照射し、走査するこ
とにより、試料から得られる信号をもとに走査像を得る
装置、いわゆる走査形電子顕微鏡（通称ＳＥＭ）では、
試料をできるだけ生の状態で観察したいという要求が最
近ますます多くなってきている。そのための方法の一つ
として、試料を冷却した状態で観察する、いわゆる試料
冷却観察装置が使用されている。また、試料室を１〜２
７０Ｐａ程度の低真空度にして試料からの水分の蒸発を
できるだけ少なくして観察する方法も用いられている。
さらに、この両者を組み合わせる方法も用いられてい
る。しかるに、高分子材料や低融点物質など、試料によ
っては、−２０℃以下の低い温度に素速く冷却し、一定
温度に調節しながら観察する場合があり、できるだけ応
答性の良い冷却装置が望ましい。また、試料室を１〜２
７０Ｐａ程度の低真空度にしても、さらには大気圧状態
にしても容易に温度調整ができるようになっていること
が望ましい。従来技術では、この点での考慮が払われて
おらず、−２０℃以下の低い温度設定が困難であった
り、試料室を１〜２７０Ｐａ程度の低真空度にすると、
温度調整を行うための加熱部材が焼損により寿命が著し
く短くなるなどの難点があった。このため、本発明者ら
は、先に、大気圧状態から試料観察時の試料室圧力状態
に至るまで、任意に加熱できる部材からなる試料冷却観
察装置を提案している。しかるに、試料温度と試料室圧
力は、試料の変形や、ダメージのない、生の状態を観察
する上で極めて大きな意味を持つことが多く、観察条件
としてきちんと表示や、記録ができるようになっている
ことが望ましい。従来はこの点での考慮はなされていな
かった。2. Description of the Related Art An apparatus for obtaining a scanning image based on a signal obtained from a sample by irradiating a sample with a convergent electron beam and scanning the so-called scanning electron microscope (commonly called SEM)
Recently, there has been an increasing demand for observing samples as raw as possible. As one of the methods for that purpose, a so-called sample cooling observation device for observing the sample in a cooled state is used. In addition, the sample chamber is
There is also used a method of observing with a low vacuum degree of about 70 Pa to minimize evaporation of water from the sample.
Furthermore, a method of combining the both is also used. However, depending on the sample such as a polymer material or a low-melting point substance, it may be cooled to a low temperature of −20 ° C. or lower quickly and observed while adjusting to a constant temperature, and a cooling device having a good responsiveness is desirable. In addition, the sample chamber is
It is desirable that the temperature can be easily adjusted even when the degree of vacuum is about 70 Pa or even at atmospheric pressure. In the prior art, no consideration has been given to this point, and it is difficult to set a low temperature of -20 ° C. or lower, or if the sample chamber has a low vacuum degree of about 1 to 270 Pa,
There has been a problem that the life of the heating member for adjusting the temperature is remarkably shortened due to burning. For this reason, the present inventors have previously proposed a sample cooling observation device including a member that can be arbitrarily heated from the atmospheric pressure state to the sample chamber pressure state during sample observation. However, the sample temperature and sample chamber pressure often have a very significant meaning in observing the raw state without deformation or damage of the sample, and it is now possible to properly display and record the observation conditions. Is desirable. Conventionally, this point has not been taken into consideration.
【０００３】[0003]
【発明が解決しようとする課題】本発明の目的は、−２
０℃以下の低い温度設定や調整が容易で、かつ大気圧状
態でも長時間温度調整が可能であり、また、試料温度と
試料室圧力の条件を随時表示することのできる試料冷却
観察装置を提供することにある。The object of the present invention is to provide -2
Provided is a sample cooling observation device that can easily set and adjust a low temperature of 0 ° C or less, can adjust the temperature for a long time even at atmospheric pressure, and can display the conditions of sample temperature and sample chamber pressure at any time. To do.
【０００４】[0004]
【課題を解決するための手段】上記の目的を達成するた
めに、本発明では、試料を冷却状態にして観察する手段
を有する走査形電子顕微鏡およびその類似装置の試料冷
却観察装置において、前記試料を載せる部材の近くに、
試料温度を調節するための加熱手段を設け、前記加熱手
段は、大気圧状態から試料観察時の試料室圧力状態に至
るまで、任意に加熱できる部材で構成する。前記加熱部
材は、白金線と絶縁物からなる発熱体と、前記発熱体を
遮蔽するケースとで構成するか、または、ニクロム線と
絶縁物からなる発熱体と、前記発熱体を遮蔽するケース
とで構成するか、または、セラミックヒータとで構成す
る。あるいは、前記加熱部材は、ガラス管内にタングス
テン線条と、窒素ガス、またはアルゴンガスのような不
活性ガスを封入した発熱体と、前記発熱体を遮蔽するケ
ースとで構成したことを特徴とする。In order to achieve the above object, the present invention provides a scanning electron microscope having a means for observing a sample in a cooled state and a sample cooling and observing device of an apparatus similar to the scanning electron microscope. Near the member on which
A heating means for adjusting the sample temperature is provided, and the heating means is composed of a member capable of arbitrarily heating from an atmospheric pressure state to a sample chamber pressure state during sample observation. The heating member is composed of a heating element made of a platinum wire and an insulator, and a case for shielding the heating element, or a heating element made of a nichrome wire and an insulator, and a case for shielding the heating element. Or a ceramic heater. Alternatively, the heating member is composed of a tungsten filament, a heating element filled with an inert gas such as nitrogen gas or argon gas in a glass tube, and a case for shielding the heating element. .
【０００５】また、前記試料温度は、温度制御手段によ
り、自動設定できるように構成するとともに、前記試料
室の圧力は、自動圧力調整手段により、自動調節できる
ように構成し、試料温度と試料室の圧力を陰極線管上に
表示できるように構成したことを特徴とする。Further, the sample temperature is configured to be automatically set by temperature control means, and the pressure of the sample chamber is automatically adjusted by automatic pressure adjusting means. It is characterized in that the pressure of is displayed on the cathode ray tube.
【０００６】上記した構成によれば、−２０℃以下の低
い温度設定や調整が容易で、かつ大気圧状態でも長時間
温度調整が可能であり、また、試料温度と試料室圧力の
条件を随時表示することのできる試料冷却観察装置を提
供することが可能となる。According to the above construction, it is easy to set or adjust the temperature as low as -20 ° C. or less, and it is possible to adjust the temperature for a long time even under atmospheric pressure. Moreover, the conditions of the sample temperature and the sample chamber pressure can be changed as needed. It is possible to provide a sample cooling observation device capable of displaying.
【０００７】[0007]
【発明の実施の形態】以下で本発明の具体的実施例を図
面を用いて詳述する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described in detail below with reference to the drawings.
【０００８】図１は本発明の一実施例である。FIG. 1 shows an embodiment of the present invention.
【０００９】同図において、対物レンズ１によって細く
絞られた電子ビーム２は、試料３上で走査され、この試
料表面より発生した２次電子や反射電子(いずれも図示
せず)が、いわゆるＳＥＭ像としての電子信号となる。
試料３は、試料室４に取付けられた試料冷却装置５によ
って冷却される。すなわち、試料３が載置されている冷
却体６の他端は、断熱材７，カバー８などからなる冷却
容器９とつながっており、例えば液体窒素のような冷却
剤１０で冷却される。試料の微動は、ステージボデー１
１とつまみ１２，真空Ｏリング１３，１４などからなる
試料微動装置１５によりＸ，Ｙ，Ｚ方向に移動できるよ
うになっている。また、試料室には、エアーロック手段
１６を介して試料処理室１７が設けられ、試料の交換や
切断などが行えるようになっている。試料の温度制御
は、試料台１８の近くに取付けられた熱電対１９と、加
熱手段２０によって行う。加熱手段２０は、試料台１８
を載せる冷却体６に密着して取付けられた加熱部材２１
と、電流導入線２２などで構成されている。温度制御
は、試料室の外側より、熱電対メータ２３と、ヒータ電
流計２４などから成る温度制御装置２５により行われ
る。加熱部材２１は、図２（ａ）に示すように、白金線
条２６と絶縁体２７，電流導入端子２８，リード線２９
および遮蔽用ケース３０などから構成されている。遮蔽
用ケース３０は、加熱時の光モレ防止と、発熱体からの
輻射熱が、試料台１８に効率よく伝わるよう、熱の良導
体（金属）で構成され、上面は冷却体６に密着し、下面
には真空排気用の孔３１を有している。発熱体に用いて
いる白金線条２６は、空気，水分に対して極めて安定で
あり、大気中で通電しても、長時間安定に加熱状態を維
持できる。また、この構造により、放出ガスが少なく、
発熱体は熱しやすく、冷めやすいので、温度制御の応答
性も速いという利点がある。したがって、大気圧条件か
ら試料観察条件（通常、２７０Ｐａ〜１０-3Ｐａ）の広
い範囲にわたって、長時間容易に温度制御が可能であ
る。なお、この温度制御は、手動で制御する方式であっ
てもよいが、プログラマブルコントロールにより自動設
定できるようになっていると、その試料に対する最適観
察温度を、自動的に長時間維持できるので、実用上便利
である。In FIG. 1, an electron beam 2 narrowed down by an objective lens 1 is scanned on a sample 3, and secondary electrons and reflected electrons (neither shown) generated from the sample surface are so-called SEM. It becomes an electronic signal as an image.
The sample 3 is cooled by the sample cooling device 5 attached to the sample chamber 4. That is, the other end of the cooling body 6 on which the sample 3 is placed is connected to a cooling container 9 including a heat insulating material 7, a cover 8 and the like, and is cooled by a coolant 10 such as liquid nitrogen. The fine movement of the sample is the stage body 1
It can be moved in the X, Y, and Z directions by a sample fine movement device 15 including 1 and a knob 12, vacuum O-rings 13 and 14. A sample processing chamber 17 is provided in the sample chamber via an air lock means 16 so that the sample can be exchanged or cut. The temperature control of the sample is performed by a thermocouple 19 mounted near the sample table 18 and a heating means 20. The heating means 20 is the sample table 18
The heating member 21 closely attached to the cooling body 6 on which the object is placed
And a current introduction line 22 and the like. The temperature control is performed from the outside of the sample chamber by a temperature control device 25 including a thermocouple meter 23 and a heater ammeter 24. As shown in FIG. 2A, the heating member 21 includes a platinum wire strip 26, an insulator 27, a current introducing terminal 28, and a lead wire 29.
And a shielding case 30 and the like. The shielding case 30 is made of a good heat conductor (metal) so that light leakage during heating is prevented and radiant heat from the heating element is efficiently transmitted to the sample table 18. The upper surface is in close contact with the cooling body 6 and the lower surface is Has a hole 31 for evacuation. The platinum filament 26 used as the heating element is extremely stable against air and moisture, and can maintain a stable heating state for a long time even when electricity is applied in the atmosphere. Also, with this structure, less gas is released,
Since the heating element is easily heated and cooled, there is an advantage that the temperature control response is fast. Therefore, temperature control can be easily performed for a long time over a wide range from atmospheric pressure conditions to sample observation conditions (usually 270 Pa to 10 −3 Pa). This temperature control may be performed manually, but if it can be automatically set by programmable control, the optimum observation temperature for the sample can be automatically maintained for a long time. It is very convenient.
【００１０】図２（ｂ）は、本発明における加熱部材の
他の一実施例であり、ニクロム線３２を、絶縁体３３の
中に封じ込み、外部を遮蔽用ケース３４で囲った加熱部
材３５の例である。FIG. 2 (b) shows another embodiment of the heating member according to the present invention, in which the nichrome wire 32 is enclosed in an insulator 33 and the outside is surrounded by a shielding case 34. Is an example of.
【００１１】図２（ｃ）は、本発明における加熱部材の
他の一実施例であり、セラミックヒータ３６で構成した
ものである。この実施例では、内部に発熱体（図示せ
ず）が密封されており、加熱部材そのものを薄く、軽量
化できる利点がある。FIG. 2C shows another embodiment of the heating member according to the present invention, which is composed of a ceramic heater 36. In this embodiment, a heating element (not shown) is sealed inside, and there is an advantage that the heating member itself can be made thin and lightweight.
【００１２】図２（ｄ）は、本発明における加熱部材の
他の一実施例であり、ガラス管３７内にタングステン線
条３８と、窒素ガス３９、またはアルゴンガスのような
不活性ガス４０を封入した発熱体４１と、発熱体を遮蔽
するケース４２とで構成したものである。この実施例で
は、タングステン線条であっても、長寿命の加熱部材を
提供できる。FIG. 2D shows another embodiment of the heating member according to the present invention, in which a tungsten filament 38 and a nitrogen gas 39 or an inert gas 40 such as argon gas are provided in a glass tube 37. The heating element 41 is enclosed, and the case 42 is provided to shield the heating element. In this embodiment, a heating member having a long life can be provided even with a tungsten filament.
【００１３】さて、図１において、温度制御装置２５か
らの試料温度信号が、ＳＥＭ像４３を観察するための陰
極線管４４に送られ、加速電圧や倍率のデータディスプ
レィと同様に試料温度４５が画面上に表示される。ま
た、真空計（例えばピラニゲージ）４６，圧力調整器４
７などと接続された自動圧力調整装置４８からの試料室
圧力信号が陰極線管４４に送られ、試料温度４５と同様
に、試料室圧力４９が画面上に表示される。これらの表
示は、別に設けられた写真撮影用陰極線管あるいはプリ
ンター（いずれも図示せず）により記録することができ
るようになっている。Now, in FIG. 1, the sample temperature signal from the temperature control device 25 is sent to the cathode ray tube 44 for observing the SEM image 43, and the sample temperature 45 is displayed on the screen like the data display of the acceleration voltage and the magnification. Displayed above. Also, a vacuum gauge (for example, Pirani gauge) 46, a pressure regulator 4
A sample chamber pressure signal from an automatic pressure adjusting device 48 connected to 7 or the like is sent to the cathode ray tube 44, and like the sample temperature 45, a sample chamber pressure 49 is displayed on the screen. These displays can be recorded by a separately provided cathode ray tube for photography or a printer (neither is shown).
【００１４】なお、図１では走査形電子顕微鏡に適用し
た場合についての実施例を示したが、本発明の内容はこ
れに限定されるものではなく、例えば走査像装置を有す
る透過形電子顕微鏡に適用した場合についても同様の効
果を奏しうる。Although FIG. 1 shows an embodiment in the case of being applied to a scanning electron microscope, the contents of the present invention are not limited to this. For example, in a transmission electron microscope having a scanning image device. The same effect can be obtained when applied.
【００１５】[0015]
【発明の効果】本発明によれば、−２０℃以下の低い温
度設定や調整が容易で、かつ大気圧状態でも長時間温度
調整が可能な試料冷却観察装置を提供することが可能と
なる。また、試料温度と試料室圧力の条件を随時表示す
ることのできる試料冷却観察装置を提供することが可能
となる。According to the present invention, it is possible to provide a sample cooling observation apparatus which can easily set and adjust a temperature as low as −20 ° C. or lower and can adjust the temperature for a long time even at atmospheric pressure. Further, it becomes possible to provide a sample cooling observation device capable of displaying the conditions of sample temperature and sample chamber pressure at any time.
【図１】本発明の一実施例を示す説明図。FIG. 1 is an explanatory view showing one embodiment of the present invention.
【図２】本発明の加熱部材の一実施例を示す説明図。FIG. 2 is an explanatory view showing an embodiment of a heating member of the present invention.
２…電子ビーム、３…試料、４…試料室、５…試料冷却
装置、６…冷却体、９…冷却容器、１０…冷却剤、１８
…試料台、１９…熱電対、２０…加熱手段、２１…加熱
部材、２２…電流導入線、２３…熱電対メータ、２４…
ヒータ電流計、２５…温度制御装置、４３…ＳＥＭ像、
４４…陰極線管、４５…試料温度、４６…真空計、４７
…圧力調整器、４８…自動圧力調整装置。2 ... Electron beam, 3 ... Sample, 4 ... Sample chamber, 5 ... Sample cooling device, 6 ... Cooling body, 9 ... Cooling container, 10 ... Coolant, 18
... sample stage, 19 ... thermocouple, 20 ... heating means, 21 ... heating member, 22 ... current introducing wire, 23 ... thermocouple meter, 24 ...
Heater ammeter, 25 ... Temperature control device, 43 ... SEM image,
44 ... Cathode ray tube, 45 ... Sample temperature, 46 ... Vacuum gauge, 47
... pressure regulator, 48 ... automatic pressure regulator.
Claims (7)
る走査形電子顕微鏡およびその類似装置の試料冷却観察
装置において、前記試料を載せる部材の近くに、試料温
度を調節するための加熱手段を設け、前記加熱手段は、
大気圧状態から試料観察時の試料室圧力状態に至るま
で、任意に加熱できる部材で構成し、試料温度と前記試
料室の圧力を陰極線管上に表示できるように構成したこ
とを特徴とする試料冷却観察装置。1. A sample cooling and observing apparatus of a scanning electron microscope and a similar apparatus having means for observing a sample in a cooled state, and heating means for adjusting the sample temperature near a member on which the sample is placed. Provided, the heating means,
Sample characterized in that it is composed of a member that can be arbitrarily heated from the atmospheric pressure state to the sample chamber pressure state during sample observation, and that the sample temperature and the pressure of the sample chamber can be displayed on the cathode ray tube. Cooling observation device.
発熱体と、前記発熱体を遮蔽するケースとで構成した請
求項１に記載の試料冷却観察装置。2. The sample cooling observation apparatus according to claim 1, wherein the heating member includes a heating element made of a platinum wire and an insulator, and a case for shielding the heating element.
なる発熱体と、前記発熱体を遮蔽するケースとで構成し
た請求項１に記載の試料冷却観察装置。3. The sample cooling observation apparatus according to claim 1, wherein the heating member includes a heating element made of a nichrome wire and an insulator, and a case that shields the heating element.
した請求項１に記載の試料冷却観察装置。4. The sample cooling observation apparatus according to claim 1, wherein the heating member is a ceramic heater.
ン線条と、窒素ガス、またはアルゴンガスのような不活
性ガスを封入した発熱体と、前記発熱体を遮蔽するケー
スとで構成した請求項１に記載の試料冷却観察装置。5. The heating member is composed of a tungsten filament, a heating element filled with an inert gas such as nitrogen gas or argon gas in a glass tube, and a case for shielding the heating element. 1. The sample cooling observation device according to 1.
動設定できるように構成した請求項１，２，３，４また
は５に記載の試料冷却観察装置。6. The sample cooling observation apparatus according to claim 1, wherein the sample temperature is automatically set by a temperature control means.
より、自動調節できるように構成した請求項１，２，
３，４，５または６に記載の試料冷却観察装置。7. The pressure in the sample chamber can be automatically adjusted by an automatic pressure adjusting means.
The sample cooling observation device according to 3, 4, 5 or 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8007095A JPH09196831A (en) | 1996-01-19 | 1996-01-19 | Specimen cooling and observing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8007095A JPH09196831A (en) | 1996-01-19 | 1996-01-19 | Specimen cooling and observing device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09196831A true JPH09196831A (en) | 1997-07-31 |
Family
ID=11656527
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8007095A Pending JPH09196831A (en) | 1996-01-19 | 1996-01-19 | Specimen cooling and observing device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09196831A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003149118A (en) * | 2001-11-14 | 2003-05-21 | Seiko Instruments Inc | Scanning probe microscope |
| WO2009157475A1 (en) * | 2008-06-24 | 2009-12-30 | 新日本製鐵株式会社 | Gas charge container, atom probe apparatus, and method for analyzing hydrogen position in material |
| JP2015090826A (en) * | 2013-11-07 | 2015-05-11 | 株式会社日立ハイテクノロジーズ | Charged particle beam device, and method of observing sample using the device |
| US10083814B2 (en) | 2013-04-02 | 2018-09-25 | Hitachi High-Technologies Corporation | Electron microscope and sample observation method |
-
1996
- 1996-01-19 JP JP8007095A patent/JPH09196831A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003149118A (en) * | 2001-11-14 | 2003-05-21 | Seiko Instruments Inc | Scanning probe microscope |
| WO2009157475A1 (en) * | 2008-06-24 | 2009-12-30 | 新日本製鐵株式会社 | Gas charge container, atom probe apparatus, and method for analyzing hydrogen position in material |
| US8567233B2 (en) | 2008-06-24 | 2013-10-29 | Nippon Steel & Sumitomo Metal Corporation | Gas charge container, atom probe apparatus, and method for analyzing hydrogen position in material |
| US10083814B2 (en) | 2013-04-02 | 2018-09-25 | Hitachi High-Technologies Corporation | Electron microscope and sample observation method |
| JP2015090826A (en) * | 2013-11-07 | 2015-05-11 | 株式会社日立ハイテクノロジーズ | Charged particle beam device, and method of observing sample using the device |
| WO2015068670A1 (en) * | 2013-11-07 | 2015-05-14 | 株式会社日立ハイテクノロジーズ | Charged particle beam device |
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