JPH0193041A - Phase difference electron microscope for magnetic domain observation - Google Patents
Phase difference electron microscope for magnetic domain observationInfo
- Publication number
- JPH0193041A JPH0193041A JP25021587A JP25021587A JPH0193041A JP H0193041 A JPH0193041 A JP H0193041A JP 25021587 A JP25021587 A JP 25021587A JP 25021587 A JP25021587 A JP 25021587A JP H0193041 A JPH0193041 A JP H0193041A
- Authority
- JP
- Japan
- Prior art keywords
- magnetization
- circuit
- component
- intensity
- electron microscope
- 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.)
- Granted
Links
- 230000005381 magnetic domain Effects 0.000 title claims description 17
- 230000005415 magnetization Effects 0.000 claims abstract description 42
- 238000001514 detection method Methods 0.000 claims description 9
- 238000010894 electron beam technology Methods 0.000 claims description 7
- 239000000284 extract Substances 0.000 claims description 2
- 238000003384 imaging method Methods 0.000 description 4
- 239000000696 magnetic material Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は走査透過電子顕微鏡を用いて磁性体の磁区観察
を可能にした磁区観察用位相差電子顕微鏡に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a phase-contrast electron microscope for observing magnetic domains, which makes it possible to observe the magnetic domains of a magnetic material using a scanning transmission electron microscope.
従来、走査透過電子顕微鏡を用いた位相差像観察法ＤＰ
Ｃ（Ｄｉｆｆｅｒｅｎｔｉａｌ Ｐｈａｓｅ Ｃｏｎ
ｔｒａｓｔ）による磁性体の磁区観察においては、対物
レンズの前側焦点の直前に置かれた磁性体試料の回折像
を、中間レンズ、投影レンズで拡大投影して円対称に４
分割または多分割された検出素子からなる検出器で検出
し、各検出素子の電子線強度を像信号として演算処理し
て磁区コントラストを得るようにしている。Conventionally, phase contrast image observation method DP using a scanning transmission electron microscope
C (Differential Phase Con
When observing the magnetic domains of a magnetic material using a magnetic material (trust), the diffraction image of a magnetic material sample placed just in front of the front focus of the objective lens is enlarged and projected using an intermediate lens and a projection lens to form a circularly symmetrical 4-diffraction image.
Detection is performed using a detector consisting of divided or multi-divided detection elements, and the electron beam intensity of each detection element is processed as an image signal to obtain magnetic domain contrast.
しかしながら、従来の磁区観察においては、特定の磁化
方向のコントラストを観察するためには、観察試料の回
転、または検出素子の像信号の選択を行う必要があり、
その上有限の検出素子では精度良く任意の磁化方向のコ
ントラストを得ることは困難である。However, in conventional magnetic domain observation, in order to observe the contrast of a specific magnetization direction, it is necessary to rotate the observation sample or select the image signal of the detection element.
Moreover, it is difficult to obtain contrast in any magnetization direction with high precision using a limited number of detection elements.
本発明は上記問題点を解決するためのもので、任意の方
向の磁化強度を観察試料を回転させる必要がなく、精度
良く観察することができる磁区観察用位相差電子顕微鏡
を徒供することを目的とする。The present invention is intended to solve the above-mentioned problems, and aims to provide a phase-contrast electron microscope for magnetic domain observation that can observe magnetization intensity in any direction with high accuracy without the need to rotate the sample. shall be.
そのために本発明の磁区観察用位相差電子顕微鏡は、対
物レンズでできた磁性体試料の回折像を、中間レンズ、
投影レンズで拡大投影して４分割された検出素子からな
る検出器で検出し、各検出素子の電子線強度を像信号と
して演算処理して磁区コントラストを得る磁区観察用（
立相差電子顕微鏡において、χ方向、Ｖ方向各々２組の
差信号により、各方向の磁化成分を算出する第１の演算
回路と、各方向の磁化成分から磁化の角度成分を算出す
る第２の演算回路と、第２の演算回路出力が所定角度範
囲内にあるときゲート信号を出力するコンパレータと、
コンパレータからのゲート信号により導通制御され、第
１の演算回路出力を抽出するゲート回路と、抽出された
所定角度範囲内の磁化成分から磁化強度を算出する第３
の演算回路と、走査信号に同期して磁化強度を表示する
表示手段とを備えたことを特徴とする。To this end, the phase-contrast electron microscope for magnetic domain observation of the present invention uses a diffraction image of a magnetic sample formed by an objective lens, an intermediate lens,
Magnetic domain observation (for magnetic domain observation (
In a phase contrast electron microscope, a first calculation circuit calculates magnetization components in each direction based on two sets of difference signals in the χ direction and V direction, and a second calculation circuit calculates an angular component of magnetization from the magnetization components in each direction. an arithmetic circuit; a comparator that outputs a gate signal when the output of the second arithmetic circuit is within a predetermined angle range;
A gate circuit whose conduction is controlled by a gate signal from a comparator and extracts the output of the first arithmetic circuit, and a third gate circuit which calculates the magnetization intensity from the extracted magnetization component within a predetermined angle range.
The present invention is characterized by comprising an arithmetic circuit and display means for displaying magnetization intensity in synchronization with a scanning signal.
本発明は、χ方向、Ｖ方向各々２＆ＩＩの差信号により
、各方向の磁化成分を算出し、各方向の磁化成分から磁
化の角度成分を算出すると共に、磁化の角度成分が所定
角度範囲内にあるとき各方向の磁化成分を抽出し、抽出
された所定角度範囲内の磁化成分から磁化強度を算出し
て表示することにより任意の方向の磁化強度を観察する
ことができる。The present invention calculates magnetization components in each direction using the difference signals of 2 & II in the χ direction and V direction, calculates the angular component of magnetization from the magnetization component in each direction, and makes sure that the angular component of magnetization is within a predetermined angular range. At some point, the magnetization intensity in any direction can be observed by extracting magnetization components in each direction, calculating and displaying the magnetization intensity from the extracted magnetization components within a predetermined angle range.
以下、実施例を図面を参照して説明する。 Examples will be described below with reference to the drawings.
第１図は本発明の磁区観察用位相差電子顕微鏡の構成を
示す図で、図中、１は電子線、２は走査コイル、３は光
軸、４は磁性体試料、５ａは照射側対物レンズ、５ｂは
結像側対物レンズ、６は中間レンズ、７は投影レンズ、
８は検出器、９は走査コイルｌ［ｊ動部、１０Ｉ、１０
ｔ、１０１．１゜４は増幅器、１１〜１３は演算回路、
１４は論理回路、１５はコンパレーク、１６は制御装置
、１７はゲート回路、１日は演算回路、１９は表示装置
である。FIG. 1 is a diagram showing the configuration of a phase contrast electron microscope for magnetic domain observation according to the present invention. In the figure, 1 is an electron beam, 2 is a scanning coil, 3 is an optical axis, 4 is a magnetic sample, and 5a is an irradiation side objective. 5b is an objective lens on the imaging side, 6 is an intermediate lens, 7 is a projection lens,
8 is a detector, 9 is a scanning coil l[j moving part, 10I, 10
t, 101.1° 4 is an amplifier, 11 to 13 are arithmetic circuits,
14 is a logic circuit, 15 is a comparator, 16 is a control device, 17 is a gate circuit, 1 is an arithmetic circuit, and 19 is a display device.
図において、電子銃（図示せず）から発生した電子線１
は、走査コイル２により（Ａ−Ａ′）または（Ｂ−Ｂ’
）のように走査され、対物レンズ５ａにより試料４に収
束される。試料４は結像側対物レンズ５ｂの前側焦点の
近傍に置かれ、２次元的にみて光軸３を中心として紙面
に垂直に左側下向（■）、右側上向（０）にそれぞれ磁
化されているものとする。In the figure, an electron beam 1 generated from an electron gun (not shown)
is (A-A') or (B-B') by the scanning coil 2.
) and is focused on the sample 4 by the objective lens 5a. The sample 4 is placed near the front focal point of the imaging side objective lens 5b, and is magnetized vertically to the plane of the paper with the optical axis 3 as the center in two-dimensional terms, downward to the left (■) and upward to the right (0). It is assumed that
この試料４へ入射角２α１で電子線を入射させると、第
２図に示すように対物レンズ５ｂの後焦点面上に直径Ｄ
＝ｆ０Ｘ２α＋ Ｃｆｏは焦点距離）のディスクパタ
ーンが生ずる。When an electron beam is incident on this sample 4 at an incident angle of 2α1, as shown in FIG.
A disk pattern of =f0X2α+Cfo is the focal length) is generated.
そして、電子線１が試料４を透過するとき、ローレン゛
ンカによって試料の磁化方向に応じて偏向され、試料照
射角に対応して（Ａ−Ａ’）は（Ｃ−Ｃ゛）に、（Ｂ−
Ｂ’）は（Ｄ−Ｄ’）となり、（Ｃ−Ｃ’）、（Ｄ−Ｄ
′）は中間レンズ６、投影レンズ７の結像作用により検
出器８上に回折ディスクとして結像投影される。When the electron beam 1 passes through the sample 4, it is deflected by the Laurent anchor according to the magnetization direction of the sample, and (A-A') becomes (C-C') according to the sample irradiation angle. B-
B') becomes (D-D'), (C-C'), (D-D
') is imaged and projected onto the detector 8 as a diffraction disk by the imaging action of the intermediate lens 6 and the projection lens 7.
一方、走査コイル２における偏向主面を物体面とみた場
合、（Ａ−Ａ’）、（Ｂ−Ｂ’）は同様に静止ディスク
パターンとして検出器８上に結像する。On the other hand, when the main deflection plane in the scanning coil 2 is regarded as the object plane, (AA') and (BB') are similarly imaged on the detector 8 as a stationary disk pattern.
従って走査コイル２により試料上を面走査した場合、試
料４の磁化方向が一定の領域では試料の走査条件によら
ず静止回折ディスク（Ｃ−Ｃ’）、又は（Ｄ−Ｄ’）が
得られ、これは磁化方向に応じて分離される。検出器８
は、図示するようにχ軸、Ｖ軸方向においてＳ８、Ｓ２
、Ｓ３、Ｓ４に分割されているので、例えば（ＳＺ
３３）の差信号を検出すれば磁区コントラストが得られ
ることになる。Therefore, when the surface of the sample is scanned by the scanning coil 2, in a region where the magnetization direction of the sample 4 is constant, a stationary diffraction disk (CC') or (D-D') can be obtained regardless of the scanning conditions of the sample. , which are separated according to the magnetization direction. Detector 8
are S8 and S2 in the χ-axis and V-axis directions as shown in the figure.
, S3, and S4, so for example (SZ
33), magnetic domain contrast can be obtained by detecting the difference signal.
各検出器Ｓｔ 、Ｓｔ 、Ｓｔ 、Ｓｓの検出信号は増
幅されて演算回路１１．１２に入力され、次の演算が行
われる。The detection signals from each of the detectors St , St , St , and Ss are amplified and input to the arithmetic circuits 11 and 12, where the following arithmetic operations are performed.
（ｓｚ ＋３３ ）−（ｓ＋ ＋Ｓ３ ）（Ｓ＋ ＋Ｓ
ｔ ） （Ｓｓ ＋Ｓａ ）この分母（Ｓ＋ ＋Ｓ
ｚ ＋Ｓ３ ＋Ｓ４）は信号を規格化するためのもので
ある。演算回路１１．１２の出力は演算回路１３に入力
される。演算回路１３においては、磁化？＝’ｉ＋Ｖと
したとき、その角度成分θに関して、
θ＝ｔａｎ −’ ｌ ｙ／χ１＋ｎπ／２が演算され
る。この場合、ｎの値は演算回路１４から入力される。(sz +33)-(s+ +S3)(S+ +S
t ) (Ss +Sa) This denominator (S+ +S
z +S3 +S4) is for normalizing the signal. The outputs of the arithmetic circuits 11 and 12 are input to the arithmetic circuit 13. In the arithmetic circuit 13, magnetization? ='i+V, then θ=tan-'ly/χ1+nπ/2 is calculated for the angle component θ. In this case, the value of n is input from the arithmetic circuit 14.
即ち論理回路１４は、出力信号χ、Ｖの正負を以下の■
〜■の条件で判断したｎの値を出力する。That is, the logic circuit 14 converts the positive and negative of the output signals χ and V into the following
The value of n determined under the conditions of ~■ is output.
■χ≧ｏ、ｙ≧０の場合：ｎ冨Ｏ
■χ＜Ｑ、ｙ≧０の場合：ｎ＝１
■χ＜Ｑ、ｙ＜Ｑの場合：ｎ＝２
■χ≧ｏ、ｙ＜Ｑの場合：ｎ＝３
コンパレータ１５は、任意の磁化方向成分θ及び選択幅
δθを選択する制御装置工６により制御され、演算回路
１３の出力θが、θ＋δθ〜θの範囲にある場合にのみ
動作し、ゲート回路１７を閉じる。その結果、演算回路
１１．１２の出力信号はゲート回路１７を経由して演算
回路１８に入力され、試料の磁化強度１１”ｌｌが次式
により算出される。■When χ≧o, y≧0: n-Ten O ■When χ<Q, y≧0: n=1 ■When χ<Q, y<Q: n=2 ■χ≧o, y<Q In the case of n=3, the comparator 15 is controlled by the control device 6 which selects an arbitrary magnetization direction component θ and selection width δθ, and operates only when the output θ of the arithmetic circuit 13 is within the range of θ+δθ to θ. Then, the gate circuit 17 is closed. As a result, the output signals of the arithmetic circuits 11 and 12 are input to the arithmetic circuit 18 via the gate circuit 17, and the magnetization intensity of the sample 11''ll is calculated by the following equation.
１閂１＝ １χＩ”＋ｌｖ１”
こうして任意の磁化方向の角度θ（θ＋６θ〜θ）を制
御装置で選択することにより、選択されたθに対する試
料の磁化強度１１”ｌｌを表示器１９で磁区コントラス
トとして観察することができる。1 bar 1 = 1χI''+lv1'' In this way, by selecting an arbitrary angle θ (θ+6θ~θ) of the magnetization direction using the control device, the magnetization strength of the sample 11”ll for the selected θ is displayed as the magnetic domain contrast on the display 19. can be observed.
以上のように本発明によれば、４分割型検出素子をχ、
Ｖ各々２分割２組の差信号として取り出すことにより試
料の磁化方向のベクトルｎをχ、Ｖとして抽出すること
ができ、任意の方向の磁化強度を観察することができる
。As described above, according to the present invention, the four-segment detection element is
By dividing each of V into two and taking out two sets of difference signals, the vector n of the magnetization direction of the sample can be extracted as χ and V, and the magnetization intensity in any direction can be observed.
第１図は本発明の磁区観察用位相差電子顕微鏡の構成を
示す図、第２図は試料のディスクパターンを示す図であ
る。
ｌ・・・電子線、２・・・走査コイル、３・・・光軸、
４・・・磁性体試料、５ａ・・・照射側対物レンズ、５
ｂ・・・結像側対物レンズ、６・・・中間レンズ、７・
・・投影レンズ、８・・・検出器、９・・・走査コイル
駆動部、１０＋、１０ｔ１１０ｓ、１０４・・・増幅器
、１１〜１３・・・演算回路、１４・・・論理回路、１
５・・・コンパレータ、１６・・・制御装置、１７・・
・ゲート回路、１８・・・演Ｘ回路、１９・・・表示装
置。
出 願 人 日本電子株式会社FIG. 1 is a diagram showing the configuration of a phase contrast electron microscope for magnetic domain observation according to the present invention, and FIG. 2 is a diagram showing a disk pattern of a sample. l...electron beam, 2...scanning coil, 3...optical axis,
4... Magnetic sample, 5a... Irradiation side objective lens, 5
b... Imaging side objective lens, 6... Intermediate lens, 7...
...Projection lens, 8...Detector, 9...Scanning coil drive unit, 10+, 10t110s, 104...Amplifier, 11-13...Arithmetic circuit, 14...Logic circuit, 1
5... Comparator, 16... Control device, 17...
- Gate circuit, 18... Performance X circuit, 19... Display device. Applicant: JEOL Ltd.
Claims (1)
、投影レンズで拡大投影して４分割された検出素子から
なる検出器で検出し、各検出素子の電子線強度を像信号
として演算処理して磁区コントラストを得る磁区観察用
位相差電子顕微鏡において、ｘ方向、ｙ方向各々２組の
差信号により、各方向の磁化成分を算出する第１の演算
回路と、各方向の磁化成分から磁化の角度成分を算出す
る第２の演算回路と、第２の演算回路出力が所定角度範
囲内にあるときゲート信号を出力するコンパレータと、
コンパレータからのゲート信号により導通制御され、第
１の演算回路出力を抽出するゲート回路と、抽出された
所定角度範囲内の磁化成分から磁化強度を算出する第３
の演算回路と、走査信号に同期して磁化強度を表示する
表示手段とを備えた磁区観察用位相差電子顕微鏡。The diffraction image of the magnetic sample formed by the objective lens is enlarged and projected using an intermediate lens and a projection lens, and detected by a detector consisting of four divided detection elements, and the electron beam intensity of each detection element is processed as an image signal. In a phase-contrast electron microscope for magnetic domain observation that obtains magnetic domain contrast, a first calculation circuit calculates magnetization components in each direction using two sets of difference signals in the x direction and y direction, and a first calculation circuit calculates magnetization components from the magnetization components in each direction. a comparator that outputs a gate signal when the output of the second arithmetic circuit is within a predetermined angle range;
A gate circuit whose conduction is controlled by a gate signal from a comparator and extracts the output of the first arithmetic circuit, and a third gate circuit which calculates the magnetization intensity from the extracted magnetization component within a predetermined angle range.
A phase-contrast electron microscope for observing magnetic domains, comprising an arithmetic circuit and display means for displaying magnetization intensity in synchronization with a scanning signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25021587A JPH0624109B2 (en) | 1987-10-03 | 1987-10-03 | Phase contrast electron microscope for magnetic domain observation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25021587A JPH0624109B2 (en) | 1987-10-03 | 1987-10-03 | Phase contrast electron microscope for magnetic domain observation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0193041A true JPH0193041A (en) | 1989-04-12 |
| JPH0624109B2 JPH0624109B2 (en) | 1994-03-30 |
Family
ID=17204540
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25021587A Expired - Lifetime JPH0624109B2 (en) | 1987-10-03 | 1987-10-03 | Phase contrast electron microscope for magnetic domain observation |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0624109B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002320669A (en) * | 2001-04-26 | 2002-11-05 | Asahi Medical Co Ltd | Method for blood filtration |
| JP2009277618A (en) * | 2008-05-19 | 2009-11-26 | Jeol Ltd | Magnetic domain structural image acquisition method and scanning transmission electron microscope |
| JP2010113972A (en) * | 2008-11-07 | 2010-05-20 | Jeol Ltd | Scanning transmission electron microscope |
| JP2014020784A (en) * | 2012-07-12 | 2014-02-03 | Astro Design Inc | Electromagnetic wave measurement system |
| EP3330997A2 (en) | 2016-12-05 | 2018-06-06 | Jeol Ltd. | Method of image acquisition and electron microscope |
| US10332720B2 (en) | 2015-09-07 | 2019-06-25 | Jeol Ltd. | Charged particle system and method for measuring deflection fields in a sample |
-
1987
- 1987-10-03 JP JP25021587A patent/JPH0624109B2/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002320669A (en) * | 2001-04-26 | 2002-11-05 | Asahi Medical Co Ltd | Method for blood filtration |
| JP2009277618A (en) * | 2008-05-19 | 2009-11-26 | Jeol Ltd | Magnetic domain structural image acquisition method and scanning transmission electron microscope |
| JP2010113972A (en) * | 2008-11-07 | 2010-05-20 | Jeol Ltd | Scanning transmission electron microscope |
| JP2014020784A (en) * | 2012-07-12 | 2014-02-03 | Astro Design Inc | Electromagnetic wave measurement system |
| US10332720B2 (en) | 2015-09-07 | 2019-06-25 | Jeol Ltd. | Charged particle system and method for measuring deflection fields in a sample |
| EP3330997A2 (en) | 2016-12-05 | 2018-06-06 | Jeol Ltd. | Method of image acquisition and electron microscope |
| US10923314B2 (en) | 2016-12-05 | 2021-02-16 | Jeol Ltd. | Method of image acquisition and electron microscope |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0624109B2 (en) | 1994-03-30 |
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