JPS6336110B2 - - Google Patents
Info
- Publication number
- JPS6336110B2 JPS6336110B2 JP60098069A JP9806985A JPS6336110B2 JP S6336110 B2 JPS6336110 B2 JP S6336110B2 JP 60098069 A JP60098069 A JP 60098069A JP 9806985 A JP9806985 A JP 9806985A JP S6336110 B2 JPS6336110 B2 JP S6336110B2
- Authority
- JP
- Japan
- Prior art keywords
- sample
- scanning
- electron beam
- image
- magnification
- 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
Links
- 238000010894 electron beam technology Methods 0.000 claims description 19
- 238000002003 electron diffraction Methods 0.000 claims description 11
- 239000013078 crystal Substances 0.000 description 5
- 238000010521 absorption reaction Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- QNRATNLHPGXHMA-XZHTYLCXSA-N (r)-(6-ethoxyquinolin-4-yl)-[(2s,4s,5r)-5-ethyl-1-azabicyclo[2.2.2]octan-2-yl]methanol;hydrochloride Chemical class Cl.C([C@H]([C@H](C1)CC)C2)CN1[C@@H]2[C@H](O)C1=CC=NC2=CC=C(OCC)C=C21 QNRATNLHPGXHMA-XZHTYLCXSA-N 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000012926 crystallographic analysis Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000000386 microscopy Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
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
- H01J37/26—Electron or ion microscopes; Electron or ion diffraction tubes
- H01J37/28—Electron or ion microscopes; Electron or ion diffraction tubes with scanning beams
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明は、特定の結晶構造を持つ領域の反射回
折顕微鏡像を得るための走査型反射電子回折顕微
装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a scanning electron diffraction microscope apparatus for obtaining a reflection diffraction microscope image of a region having a specific crystal structure.
従来の電子ビーム走査方式では、第1図aに示
すように長方形A,B,C,Dの領域を一次電子
ビーム1で走査する。いろいろの結晶構造を見る
ために、試料2は回転軸3の囲りで回転させられ
る。このとき、一般には、走査X′軸が試料の回
転軸方向とαの角度を持つて交つているので、試
料表面での走査領域4は斜方形A,B′,C′,
D′になる。像を観察するための陰極線管上では、
この斜方形の領域をA,B,C,Dに相似形の長
方形の画面上で表示するために、ひずんだ像を観
測することになる。仮に、第1図bに示すよう
に、走査領域A,B,C,DのX軸が試料回転軸
3と一致しても、一次電子ビーム1の試料2に対
する視斜角θが小さいので、試料表面での走査領
域4はA.B′,C′,Dのように一次電子ビーム1
の入射方向に関して極端に延びたものになる。こ
の領域を長方形A,B,C,Dに相似形の陰極線
管上で観測するために、Y方向に関して極端に圧
縮された像となり、非常に見にくい像となる。
In the conventional electron beam scanning method, rectangular areas A, B, C, and D are scanned with a primary electron beam 1, as shown in FIG. 1a. In order to view different crystal structures, the sample 2 is rotated around an axis of rotation 3. At this time, since the scanning X' axis generally intersects the rotation axis direction of the sample at an angle of α, the scanning area 4 on the sample surface is shaped like a rhomboid A, B', C',
becomes D′. On a cathode ray tube for observing images,
In order to display this rhombic area on a rectangular screen similar to A, B, C, and D, a distorted image will be observed. Even if the X axes of the scanning areas A, B, C, and D coincide with the sample rotation axis 3 as shown in FIG. 1b, the oblique angle θ of the primary electron beam 1 with respect to the sample 2 is small, so The scanning area 4 on the sample surface is the primary electron beam 1 like AB', C', and D.
becomes extremely elongated with respect to the direction of incidence. Since this region is observed on a cathode ray tube shaped similarly to rectangles A, B, C, and D, the image is extremely compressed in the Y direction, making it extremely difficult to see.
従来、これらのひずみをすべて持つていない走
査型反射電子回折顕微装置は知られていなかつ
た。 Conventionally, there has been no known scanning electron diffraction microscopy device that does not have all of these distortions.
なお、この種の装置として関連するものには例
えば公開実用新案公報昭55−10212号、公開特許
公報昭49−131375号および公開特許公報昭50−
31770号等が挙げられる。 In addition, related devices of this type include, for example, Published Utility Model Publication No. 10212-1980, Published Patent Publication No. 131375-1982, and Published Patent Publication No. 1982-1982.
Examples include No. 31770.
本発明の目的は、したがつて、一次電子ビーム
の視斜角が小さいことに基因するこれらのひずみ
およびぼけを取除くことによつて、表面の結晶構
造分布の観測をきわめて容易にする走査型反射電
子回折顕微装置を提供することである。
Therefore, an object of the present invention is to provide a scanning type that greatly facilitates the observation of the crystal structure distribution on the surface by removing these distortions and blurs caused by the small oblique angle of the primary electron beam. An object of the present invention is to provide a reflection electron diffraction microscope device.
上記目的を達成するために、本発明による走査
型反射電子回折顕微装置は、一次電子ビームのX
方向の走査が試料の回転軸に一致するようにビー
ム走査方向の回転を行なう手段、上記試料の傾き
に応じて横倍率に対する縦倍率の比を変えるため
に縦倍率と横倍率を独立に可変させる手段、およ
び電子ビームをY方向に偏向するY方向偏向電流
に対応する電流をレンズ電流に重畳させてダイナ
ミツク・フオーカスを行なう手段を含むことを要
旨とする。
In order to achieve the above object, a scanning backscattered electron diffraction microscope device according to the present invention has an X
A means for rotating the beam scanning direction so that the scanning direction coincides with the rotation axis of the sample, and independently varying the vertical magnification and the horizontal magnification in order to change the ratio of the vertical magnification to the horizontal magnification according to the inclination of the sample. and means for superimposing a current corresponding to a Y-direction deflection current for deflecting an electron beam in the Y-direction on a lens current to perform dynamic focusing.
以下、本発明を図面を用いて詳細に説明する。 Hereinafter, the present invention will be explained in detail using the drawings.
第2図は本発明による走査型反射電子回折顕微
装置の基本的な構成を示すブロツク図である。同
図において20kV程度の加速電源5を有する電子
銃6から放出された一次電子ビーム1は収束レン
ズ7により真空容器8内にある試料2の表面に5゜
以下の視斜角θを持つて収束される。偏向コイル
群9,10を動作させて一次電子ビーム1を試料
2の表面上で走査させる。そのとき得られる試料
2の吸収電流信号を陰極線管(以下本明細書にお
いてはCRTと略称する)11の輝度変調信号に
かえてCRT11上に試料2の吸収電流像を得る。
この吸収電流像から、試料2上の分析すべき場所
を選択する。この分析点に一次電子ビーム1を固
定照射することによつて得られる反射電子回折線
12は螢光スクリーン13上にのぞき窓14を通
して観測される。この反射電子回折線12を解析
することによつて、試料2の表面上の任意の場所
の結晶状態、つまり試料2の表面部分を構成する
原子の配列状態を分析することが可能となる。さ
らに、スポツト選択機構15により、ある特定の
回折スポツトを選び、光電変換素子(例えば光電
子増倍管)16から得られる電気信号を一次電子
線1の走査に同期させてCRT11の輝度変調信
号に変えることによつて、CRT11上に反射回
折顕微鏡像が得られる。この顕微鏡像から試料2
の表面のある特定の結晶構造を持つ領域がわか
り、試料2の表面の結晶解析の有力な手段とな
る。 FIG. 2 is a block diagram showing the basic configuration of a scanning electron diffraction microscope apparatus according to the present invention. In the figure, a primary electron beam 1 emitted from an electron gun 6 having an accelerating power source 5 of about 20 kV is focused by a converging lens 7 onto the surface of a sample 2 in a vacuum container 8 with an oblique angle θ of 5° or less. be done. The deflection coil groups 9 and 10 are operated to scan the primary electron beam 1 over the surface of the sample 2. The absorption current signal of the sample 2 obtained at this time is converted into a brightness modulation signal of a cathode ray tube (hereinafter referred to as CRT) 11 to obtain an absorption current image of the sample 2 on the CRT 11.
From this absorption current image, a location on the sample 2 to be analyzed is selected. A reflected electron diffraction line 12 obtained by fixedly irradiating this analysis point with the primary electron beam 1 is observed through a peephole 14 on a fluorescent screen 13. By analyzing this reflected electron diffraction line 12, it becomes possible to analyze the crystalline state at any location on the surface of the sample 2, that is, the arrangement state of atoms constituting the surface portion of the sample 2. Furthermore, a specific diffraction spot is selected by a spot selection mechanism 15, and an electric signal obtained from a photoelectric conversion element (for example, a photomultiplier tube) 16 is synchronized with the scanning of the primary electron beam 1 and converted into a brightness modulation signal for the CRT 11. As a result, a reflection diffraction microscope image is obtained on the CRT 11. From this microscopic image, sample 2
The region with a specific crystal structure on the surface of sample 2 can be identified, and this becomes an effective means for crystallographic analysis of the surface of sample 2.
本発明によれば、上記装置に、第1図aに示す
ひずみを除去するためのローテーシヨン回路1
7、第1図bに関連して述べたひずみを除去する
ための倍率独立可変回路18、増幅器19、およ
び重畳器20が備えられる。 According to the invention, a rotation circuit 1 for removing distortion shown in FIG.
7. A magnification independent variable circuit 18, an amplifier 19, and a superimposition device 20 are provided for removing the distortion described in connection with FIG. 1b.
第1図aに示すひずみを除去するために、走査
方向を走査領域A,B,C,DのX軸を試料回転
軸と一致するように回転すれば、試料表面での走
査領域は第1図bに示す長方形A,B′,C′,Dと
なり、CRT11上の像のひずみは除去できる。
この回転操作はローテーシヨン回路17によつて
次のように行なわれる。これは座標系X′―Y′と
座標系―X―Yとの間の座標回転と等価であるの
で、いまCRT11より発生する偏向電流IX′,
IY′をsineおよびcosineを発生するポテンシヨメー
タを使用し、IX=IX′cos+IY′sin,IY=I−X′
sin+LY′cosなる式にしたがつて重畳すれば、
第1図bの状態が実現できる。これが実現された
かどうかの確認は、試料回転軸に平行な辺をもつ
参照とする矩形像のX軸、あるいはY軸がCRT
11のX軸あるいはY軸に一致するまで、sine及
びcosineのポテンシヨメータのゲインを変化させ
ることによつて容易に行なうことができる。 In order to remove the distortion shown in Figure 1a, if the scanning direction is rotated so that the X axes of scanning areas A, B, C, and D coincide with the sample rotation axis, the scanning area on the sample surface will be The rectangles A, B', C', and D shown in FIG. b are obtained, and the distortion of the image on the CRT 11 can be removed.
This rotation operation is performed by the rotation circuit 17 as follows. This is equivalent to coordinate rotation between the coordinate system X'-Y' and the coordinate system -X-Y, so the deflection current I
Using a potentiometer that generates sine and cosine for I Y ′ , I
If we superimpose according to the formula sin + L Y ′cos, we get
The state shown in FIG. 1b can be realized. To check whether this has been achieved, the X-axis or Y-axis of the reference rectangular image with sides parallel to the sample rotation axis must be
This can be easily done by changing the gains of the sine and cosine potentiometers until they coincide with the X-axis or Y-axis of No. 11.
第1図bに関連して述べたひずみは、倍率独立
可変回路18によつて除去される。この回路によ
りX方向とY方向の倍率を独立に変えることがで
きるようにする。このとき、第3図bに示すよう
に、Y方向の走査領域を小さくしA,B,C,D
の領域を走査すれば、試料表面上での走査領域4
は長方形A,B′,C′,Dとなる。この長方形の辺
の長さA,B′を第3図aに示す長方形の辺の長
さA,Bに一致させれば、CRT11に表示され
る像は、あたかも試料垂直方向から見たものにな
り、表面の構造の観測がきわめて容易になる。実
際に垂直方向から観測するようにするためには、
一次電子ビーム1の視斜角θを読み取り、X方向
の倍率に対してY方向の倍率を常に1/sinθ倍す
ることによつて、あるいは正方形をした参照像が
CRT11上で正方形に見えるようにY方向の倍
率を変化させることによつて、容易に実行でき
る。 The distortions mentioned in connection with FIG. 1b are eliminated by the independent variable magnification circuit 18. This circuit allows the magnification in the X and Y directions to be changed independently. At this time, as shown in Figure 3b, the scanning area in the Y direction is made smaller and A, B, C, D
If the area is scanned, the scanning area 4 on the sample surface is
become rectangles A, B', C', and D. If the side lengths A and B' of this rectangle are made to match the side lengths A and B of the rectangle shown in Figure 3a, the image displayed on the CRT 11 will appear as if it were viewed from the vertical direction of the sample. This makes it extremely easy to observe the surface structure. In order to actually observe from the vertical direction,
By reading the oblique angle θ of the primary electron beam 1 and always multiplying the magnification in the Y direction by 1/sinθ with respect to the magnification in the X direction, or by
This can be easily done by changing the magnification in the Y direction so that it looks like a square on the CRT 11.
しかし、一次電子ビーム1の視斜角が小さいこ
とから生ずる像のぼけがなお存在する。それは第
4図に示すように、試料表面のある一点において
一次電子ビームをフオーカスさせても、Y方向に
ビームを走査するとき、その上下方向で像にぼけ
が生じてしまう。第2図に示す増幅器19および
重畳器20を用いて、レンズ電流ILにY方向の偏
向電流ΔIY′を重畳させ、ダイナミツク・フオー
カスを実行し、常に試料表面上でフオーカスさせ
るようにすることによつて、このぼけは除去する
ことができる。第4図bのぼけを示す量Δbは、
レンズ電流をIL、加速電圧をVおよび偏向電流を
ΔIY′とすると、
Δb=−f(IL・V)・ΔIY′
で与えられる。ここで、fはIL、Vのある関数で
ある。 However, there is still image blurring resulting from the small oblique angle of the primary electron beam 1. As shown in FIG. 4, even if the primary electron beam is focused at a certain point on the sample surface, when the beam is scanned in the Y direction, the image will be blurred in the vertical direction. Using an amplifier 19 and a superimposing device 20 shown in FIG. 2, a Y-direction deflection current ΔI Y ' is superimposed on the lens current I L to perform dynamic focusing so that the focus is always on the sample surface. This blur can be removed by The amount Δb indicating the blur in FIG. 4b is
When the lens current is I L , the accelerating voltage is V, and the deflection current is ΔI Y ', it is given by Δb=-f( IL ·V)·ΔI Y '. Here, f is a function of I L and V.
それ故、増幅器19でY方向の偏向電流ΔIYを
適当な大きさにしてレンズ電流ILに重畳器20に
よつて重畳してやれば、試料表面の全走査領域で
一次電子ビームはフオーカスされ、像のぼけを除
去することができる。実際に全走査領域でぼけを
除去するためには、CRT11の全画面上でぼけ
がないように増幅器19のゲインを変えることに
よつて容易に行なうことができる。また、上記操
作をほどこした像を観測しながら、一次電子ビー
ムのスポツト形状を変化させるステイグマトール
を働かせ、Y方向とX方向の像の鮮鋭度を一致さ
せることによつて、X方向とY方向の面積分解能
を同程度にすることも可能である。 Therefore, if the Y-direction deflection current ΔI Y is set to an appropriate magnitude by the amplifier 19 and superimposed on the lens current I L by the superimposer 20, the primary electron beam will be focused in the entire scanning area of the sample surface, and the image will be Blur can be removed. In fact, blurring can be easily removed in the entire scanning area by changing the gain of the amplifier 19 so that there is no blurring on the entire screen of the CRT 11. In addition, while observing the image that has been subjected to the above operation, a stigmator that changes the spot shape of the primary electron beam is activated to match the sharpness of the image in the Y direction and the X direction. It is also possible to make the area resolution of
以上述べてきた像のローテーシヨン機能、X倍
率とY倍率の独立可変機能およびダイナミツク・
フオーカス機能は、個々には良く知られているも
のである。しかし、走査型反射電子回折顕微装置
のように、一次電子ビームの視射角がきわめて小
さい場合、上記三つの機能の組合せが必須とな
る。これにより、像のひずみおよびぼけを取除く
ことによつて、表面の結晶構造の分布の観測をき
わめて容易によるという優れた利点が生じる。
The image rotation function described above, the independent variable function of X magnification and Y magnification, and the dynamic
The focus function is individually well known. However, when the glancing angle of the primary electron beam is extremely small, such as in a scanning backscattered electron diffraction microscope, a combination of the above three functions is essential. This has the great advantage that by removing image distortion and blurring, it is extremely easy to observe the distribution of the crystal structure on the surface.
第1図は像回転の機能を説明するためのa偏向
方向回転前およびb偏向方向回転後の斜視図、第
2図は本発明による走査型反射電子回折顕微装置
の基本的な構成を示すブロツク図、第3図は像の
X―Y倍率の倍率独立可変機能を説明するための
a倍率独立可変前およびb倍率独立可変後の斜視
図、第4図はダイナミツク・フオーカス機能を説
明するためのaダイナミツク・フオーカス前およ
びbダイナミツク・フオーカス後の側面図であ
る。
1…一次電子ビーム、2…試料、3…試料回転
軸、4…試料表面での走査領域、5…加速電源、
6…電子銃、7…収束レンズ、8…真空容器、
9,10…偏向コイル群、11…陰極線管
(CRT)、12…反射電子回折線、13…螢光ス
クリーン、14…のぞき窓、15…スポツト選択
機構、16…光電変換素子、17…ローテーシヨ
ン回路、18…倍率独立可変回路、19…増幅
器、20…重畳器。
Fig. 1 is a perspective view of a before rotation of the deflection direction and b after rotation of the deflection direction to explain the function of image rotation, and Fig. 2 is a block diagram showing the basic configuration of a scanning backscattered electron diffraction microscope according to the present invention. Figure 3 is a perspective view of a before independent variable magnification and b after independent variable magnification to explain the function of independently varying the XY magnification of the image, and Figure 4 is a perspective view of the function to explain the dynamic focus function. FIG. 3 is a side view of a before dynamic focus and a side view of b after dynamic focus. DESCRIPTION OF SYMBOLS 1... Primary electron beam, 2... Sample, 3... Sample rotation axis, 4... Scan area on sample surface, 5... Acceleration power source,
6...electron gun, 7...converging lens, 8...vacuum container,
9, 10... Deflection coil group, 11... Cathode ray tube (CRT), 12... Reflected electron diffraction line, 13... Fluorescent screen, 14... Peephole, 15... Spot selection mechanism, 16... Photoelectric conversion element, 17... Rotation Circuit, 18... Magnification independent variable circuit, 19... Amplifier, 20... Superimposing device.
Claims (1)
軸に一致するようにビーム走査方向の回転を行な
う手段、上記試料の傾きに応じて横倍率に対する
縦倍率の比を変えるために縦倍率と横倍率を独立
に可変させる手段、および電子ビームをY方向に
偏向するY方向偏向電流に対応する電流をレンズ
電流に重畳させてダイナミツク・フオーカスを行
なう手段を含むことを特徴とする走査型反射電子
回折顕微装置。1. Means for rotating the beam scanning direction so that the scanning of the primary electron beam in the X direction coincides with the rotation axis of the sample; Scanning backscattered electron diffraction characterized by comprising means for independently varying magnification, and means for performing dynamic focusing by superimposing a current corresponding to a Y-direction deflection current for deflecting an electron beam in the Y-direction on a lens current. Microscope equipment.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9806985A JPS60236444A (en) | 1985-05-10 | 1985-05-10 | Scanning-type reflected-electron-diffracting microscope |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9806985A JPS60236444A (en) | 1985-05-10 | 1985-05-10 | Scanning-type reflected-electron-diffracting microscope |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS60236444A JPS60236444A (en) | 1985-11-25 |
JPS6336110B2 true JPS6336110B2 (en) | 1988-07-19 |
Family
ID=14210048
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP9806985A Granted JPS60236444A (en) | 1985-05-10 | 1985-05-10 | Scanning-type reflected-electron-diffracting microscope |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS60236444A (en) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4327726Y1 (en) * | 1965-12-29 | 1968-11-15 | ||
JPS4913903A (en) * | 1972-05-22 | 1974-02-06 | ||
JPS5011761A (en) * | 1973-06-04 | 1975-02-06 |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5510212U (en) * | 1978-07-06 | 1980-01-23 |
-
1985
- 1985-05-10 JP JP9806985A patent/JPS60236444A/en active Granted
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4327726Y1 (en) * | 1965-12-29 | 1968-11-15 | ||
JPS4913903A (en) * | 1972-05-22 | 1974-02-06 | ||
JPS5011761A (en) * | 1973-06-04 | 1975-02-06 |
Also Published As
Publication number | Publication date |
---|---|
JPS60236444A (en) | 1985-11-25 |
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