JPH0950781A - Scanning electron microscope - Google Patents
Scanning electron microscopeInfo
- Publication number
- JPH0950781A JPH0950781A JP7202347A JP20234795A JPH0950781A JP H0950781 A JPH0950781 A JP H0950781A JP 7202347 A JP7202347 A JP 7202347A JP 20234795 A JP20234795 A JP 20234795A JP H0950781 A JPH0950781 A JP H0950781A
- Authority
- JP
- Japan
- Prior art keywords
- sample
- secondary electron
- electrode
- detection electrode
- 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.)
- Pending
Links
- 238000001514 detection method Methods 0.000 claims description 104
- 238000010894 electron beam technology Methods 0.000 claims description 12
- 230000000694 effects Effects 0.000 claims description 5
- 238000010586 diagram Methods 0.000 description 13
- 239000012212 insulator Substances 0.000 description 8
- 150000002500 ions Chemical class 0.000 description 8
- 230000005684 electric field Effects 0.000 description 6
- 238000000034 method Methods 0.000 description 5
- 230000003321 amplification Effects 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、試料からの２次電
子を低真空のガス雰囲気中で増倍した後に検出する環境
制御型の走査型電子顕微鏡に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an environment control type scanning electron microscope which detects secondary electrons from a sample after multiplying them in a low vacuum gas atmosphere.
【０００２】[0002]
【従来の技術】環境制御型の走査型電子顕微鏡は、試料
から発生する２次電子を電子増倍作用を有するガス（例
えば水蒸気）が供給された低真空環境の下で増倍し、増
倍された２次電子を検出電極で検出するものである。こ
の種の顕微鏡によれば、通常の電子顕微鏡では観察でき
ないような種々の試料を観察することができる。2. Description of the Related Art An environment-controlled scanning electron microscope multiplies secondary electrons generated from a sample in a low vacuum environment supplied with a gas (eg, water vapor) having an electron multiplying effect, and multiplies them. The secondary electrodes thus detected are detected by the detection electrodes. According to this type of microscope, it is possible to observe various samples that cannot be observed by an ordinary electron microscope.
【０００３】従来の環境制御型の走査型電子顕微鏡の一
例を図１３に示す。この例では、電子銃１が収納された
真空室２と試料室１４とが圧力制限オリフィス８を介し
て接している。圧力制限オリフィス８の周囲には一枚の
円板状の２次電子検出電極９が配置される。２次電子検
出電極９は絶縁体７を介して真空室２の下端に取り付け
られる。試料室１４には、圧力制限バルブ１６を介して
気体供給源１７よりガス増幅を行う気体が供給される。
試料室１４のガス圧力（真空度）は、バルブ１６の開度
と真空ポンプ１５の動作の制御により０．１〜数１０Ｔ
orr程度に保たれる。試料室１４の気体は圧力制限オリ
フィス８を通じて真空室２にも流入するが、真空ポンプ
３により真空室２の圧力は試料室１４のそれよりも小さ
い圧力（真空度の高い状態）、例えば圧力制限オリフィ
ス８の真上で１０-2〜１０-3Ｔorr程度に保たれる。な
お、実際には、真空室２は不図示のオリフィスにより複
数の部屋に区分される。それぞれの部屋は、別々の真空
ポンプにて真空排気される（このような排気方法を差動
排気と呼ぶ）。従って、真空室２の圧力は上側の部屋ほ
ど小さく、電子銃１の置かれた部屋で最小となる。試料
室１４の内部には、観察対象の試料１３が収納される。
２次電子検出電極９には、ハーメチックシール１０を介
して可変電圧源１１より試料１３に対する正の電圧が印
加される。２次電子検出電極９に取り込まれる２次電子
信号はプリアンプ１２を介して不図示の処理装置に送ら
れる。An example of a conventional environment control type scanning electron microscope is shown in FIG. In this example, the vacuum chamber 2 accommodating the electron gun 1 and the sample chamber 14 are in contact with each other via the pressure limiting orifice 8. A disk-shaped secondary electron detection electrode 9 is arranged around the pressure limiting orifice 8. The secondary electron detection electrode 9 is attached to the lower end of the vacuum chamber 2 via the insulator 7. A gas for amplifying gas is supplied to the sample chamber 14 from a gas supply source 17 via a pressure limiting valve 16.
The gas pressure (vacuum degree) of the sample chamber 14 is 0.1 to several tens of T depending on the control of the opening degree of the valve 16 and the operation of the vacuum pump 15.
It is kept at orr level. The gas in the sample chamber 14 also flows into the vacuum chamber 2 through the pressure limiting orifice 8. However, the vacuum pump 3 causes the pressure in the vacuum chamber 2 to be lower than that in the sample chamber 14 (high vacuum state), for example, pressure limiting. It is maintained at about 10 −2 to 10 −3 Torr just above the orifice 8. The vacuum chamber 2 is actually divided into a plurality of chambers by an orifice (not shown). Each room is evacuated by a separate vacuum pump (such an exhaust method is called differential exhaust). Therefore, the pressure in the vacuum chamber 2 is smaller in the upper chamber, and is the smallest in the chamber in which the electron gun 1 is placed. A sample 13 to be observed is stored inside the sample chamber 14.
A positive voltage with respect to the sample 13 is applied to the secondary electron detection electrode 9 from the variable voltage source 11 via the hermetic seal 10. The secondary electron signal taken into the secondary electron detection electrode 9 is sent to a processing device (not shown) via the preamplifier 12.
【０００４】試料１３の観察時には、真空室２の内部の
電子銃１から放出された１次電子のビームがコンデンサ
レンズ４、対物レンズ６により圧力制限オリフィス８を
通過して試料１３上に集束され、この集束された１次電
子ビームがスキャンコイル５にて走査される。このと
き、試料１３から放出される２次電子は、２次電子検出
電極９が作り出す電場中でガス分子と衝突を繰り返して
増倍され、その後に２次電子検出電極９に取り込まれ
る。ガス増幅の過程で正のイオンが生成され、その正イ
オンは試料１３に降り注ぐ。従って、試料１３が絶縁物
であっても、１次電子ビームの照射による負の帯電が中
和され、導電処理が不要となる。When observing the sample 13, the beam of primary electrons emitted from the electron gun 1 inside the vacuum chamber 2 passes through the pressure limiting orifice 8 by the condenser lens 4 and the objective lens 6 and is focused on the sample 13. The focused primary electron beam is scanned by the scan coil 5. At this time, the secondary electrons emitted from the sample 13 are repeatedly multiplied by colliding with gas molecules in the electric field created by the secondary electron detection electrode 9, and then are captured by the secondary electron detection electrode 9. Positive ions are generated in the process of gas amplification, and the positive ions fall on the sample 13. Therefore, even if the sample 13 is an insulator, the negative charge due to the irradiation of the primary electron beam is neutralized, and the conductive treatment is unnecessary.
【０００５】[0005]
【発明が解決しようとする課題】上述した図１３の電子
顕微鏡による試料の観察を、人間が試料を直接観察する
場合に例えると、２次電子検出電極９が試料の照明源
に、電子銃１が観察者の目にそれぞれ相当する。図１３
の例では、電子銃１から放出された１次電子ビームと２
次電子検出電極９とが同軸上にあるため、得られる２次
電子像（試料像）は真上から試料を照明し、真上からそ
れを見たような像となる。従って、影のない凹凸感に乏
しい像しか得られず、試料１３の表面状態の判別が困難
なことがある。例えば、図１４に示したように断面が台
形状の試料１３を図の左方から右方へ電子ビームで走査
した場合、試料１３の左側面１３ａ、上面１３ｂ及び右
側面１３ｃからそれぞれ放出された２次電子ｓｅ１、ｓ
ｅ２、ｓｅ３がいずれもガス増倍されて２次電子検出電
極９に取り込まれる。従って、２次電子検出電極９にて
検出される２次電子信号は、図１５に示すように試料１
３の段差部分である側面１３ａ、１３ｃの位置（一点鎖
線Ａ、Ｂの位置）で略等しいピーク値を示し、両ピーク
値の間（試料１３の上面１３ｂに相当）が凸なのか凹な
のか判別し難い。When the observation of the sample by the electron microscope of FIG. 13 described above is compared with the case where a human directly observes the sample, the secondary electron detection electrode 9 serves as an illumination source of the sample and the electron gun 1 Correspond to the eyes of the observer. FIG.
, The primary electron beam emitted from the electron gun 1 and the
Since the secondary electron detection electrode 9 and the secondary electron detection electrode 9 are coaxial, the obtained secondary electron image (sample image) illuminates the sample from directly above and becomes an image as if it was viewed from directly above. Therefore, only an image with no unevenness and no shadow can be obtained, and it may be difficult to determine the surface state of the sample 13. For example, when a sample 13 having a trapezoidal cross section as shown in FIG. 14 is scanned with an electron beam from the left side to the right side of the drawing, the light is emitted from the left side surface 13a, the upper surface 13b, and the right side surface 13c of the sample 13, respectively. Secondary electrons se1, s
Both e2 and se3 are gas-multiplied and taken into the secondary electron detection electrode 9. Therefore, the secondary electron signal detected by the secondary electron detection electrode 9 is the sample 1 as shown in FIG.
Peak values are substantially equal at the positions of the side surfaces 13a and 13c (positions of the alternate long and short dash lines A and B) which are the stepped portions of 3, and whether the peak values (corresponding to the upper surface 13b of the sample 13) are convex or concave. It's hard to tell.
【０００６】本発明の目的は、２次電子をガス増倍して
検出する環境制御型の走査型電子顕微鏡において、凹凸
感を強調した試料像を形成可能とすることにある。An object of the present invention is to make it possible to form a sample image in which an unevenness is emphasized in an environment control type scanning electron microscope which detects secondary electrons by multiplying them by gas.
【０００７】[0007]
【課題を解決するための手段】本発明の実施の形態を示
す図１及び図２を参照して説明すると、請求項１の発明
は、１次電子の照射に応答して試料１３から発生した２
次電子を低真空のガス雰囲気中で増倍して２次電子検出
手段に取り込む走査型電子顕微鏡に適用される。そし
て、２次電子検出手段が、１次電子のビーム軌道を取り
囲むように設けられる第１の２次電子検出電極９と、第
１の２次電子検出電極９の外周の一部の領域に設けられ
る第２の２次電子検出電極１８と、を有することによ
り、上述した目的を達成する。図６及び図７を参照して
説明すると、請求項２の発明では、請求項１記載の走査
型電子顕微鏡において、第１の２次電子検出電極２２
Ａ、２２Ｂが、ビーム軌道の周方向に電気的に分割され
た状態で複数設けられている。図１１を参照して説明す
ると、請求項３の発明では、請求項１記載の走査型電子
顕微鏡において、第２の２次電子検出電極１８が、ビー
ム軌道の周方向に複数設けられている。図１を参照して
説明すると、請求項４の発明では、請求項１記載の走査
型電子顕微鏡において、第１の２次電子検出電極９にて
検出された２次電子信号と、第２の２次電子検出電極１
８にて検出された２次電子信号とを所定の割合で加算す
る処理回路２１を備える。図６及び図７を参照して説明
すると、請求項５の発明では、１次電子の照射に応答し
て試料から発生した２次電子を低真空のガス雰囲気中で
増倍して２次電子検出電極２２Ａ、２２Ｂに取り込む走
査型電子顕微鏡において、２次電子検出電極２２Ａ、２
２Ｂを、ビーム軌道の周方向に電気的に分割された状態
で複数設けて上述した目的を達成する。図１及び図２を
参照して説明すると、請求項６の発明では、１次電子の
照射に応答して試料１３から発生した２次電子を低真空
のガス雰囲気中で増倍して２次電子検出手段に取り込む
走査型電子顕微鏡において、２次電子検出手段が、試料
１３の鉛直上方に設けられる第１の２次電子検出電極９
と、第１の２次電子検出電極９の外周の一部の領域に設
けられる第２の２次電子検出電極１８と、を有すること
により、上述した目的を達成する。請求項７の発明で
は、電子線源１から射出された１次電子の通路を形成す
る真空室２と、真空室２に圧力制限開口８を介して連設
され、内部には試料１３が収納される試料室１４と、試
料室１４を真空排気する真空排気手段１５と、試料室１
４内において圧力制限開口８を周方向に取り囲むように
設けられる第１の電極９と、試料室１４内において第１
の電極９の外周の一部の領域に設けられる第２の電極１
８と、試料１３に対する正の電圧を第１の電極９及び第
２の電極１８に印加する電圧源１１、１９と、電子増倍
作用を有するガスを試料室１４内の第１の電極９及び第
２の電極１８と試料１３との間に供給するガス供給手段
１７と、を具備する走査型電子顕微鏡により、上述した
目的を達成する。図６及び図７を参照して説明すると、
請求項８の発明では、電子線源１から射出された１次電
子の通路を形成する真空室２と、真空室２に圧力制限開
口８を介して連設され、内部には試料１３が収納される
試料室１４と、試料室１４を真空排気する真空排気手段
１５と、圧力制限開口８の周方向に電気的に分割された
状態で試料室１４内に設けられる複数の電極２２Ａ、２
２Ｂと、試料１３に対する正の電圧を複数の電極２２
Ａ、２２Ｂに印加する電圧源２４Ａ、２４Ｂと、電子増
倍作用を有するガスを試料室１４内の複数の電極２２
Ａ、２２Ｂと試料１３との間に供給するガス供給手段１
７と、を具備する走査型電子顕微鏡により、上述した目
的を達成する。1 and 2, which show an embodiment of the present invention, the invention of claim 1 is generated from a sample 13 in response to irradiation with primary electrons. Two
It is applied to a scanning electron microscope in which secondary electrons are multiplied in a low-vacuum gas atmosphere and taken into secondary electron detection means. Then, the secondary electron detection means is provided in the first secondary electron detection electrode 9 provided so as to surround the beam trajectory of the primary electron, and in a part of the outer circumference of the first secondary electron detection electrode 9. And the second secondary electron detection electrode 18 which is provided, the above-mentioned object is achieved. Referring to FIGS. 6 and 7, in the invention of claim 2, in the scanning electron microscope according to claim 1, the first secondary electron detection electrode 22 is provided.
A and 22B are provided in a state of being electrically divided in the circumferential direction of the beam orbit. Referring to FIG. 11, in the invention of claim 3, in the scanning electron microscope according to claim 1, a plurality of second secondary electron detection electrodes 18 are provided in the circumferential direction of the beam orbit. Referring to FIG. 1, in the invention of claim 4, in the scanning electron microscope according to claim 1, the secondary electron signal detected by the first secondary electron detection electrode 9 and the second electron signal are detected. Secondary electron detection electrode 1
A processing circuit 21 for adding the secondary electron signal detected at 8 at a predetermined ratio is provided. Explaining with reference to FIGS. 6 and 7, in the invention of claim 5, the secondary electrons generated from the sample in response to the irradiation of the primary electrons are multiplied in a low-vacuum gas atmosphere to generate the secondary electrons. In the scanning electron microscope taken in the detection electrodes 22A, 22B, the secondary electron detection electrodes 22A, 2
A plurality of 2B are provided in a state of being electrically divided in the circumferential direction of the beam orbit to achieve the above-mentioned object. Referring to FIGS. 1 and 2, in the invention of claim 6, the secondary electrons generated from the sample 13 in response to the irradiation of the primary electrons are multiplied in a low-vacuum gas atmosphere to be secondary electrons. In the scanning electron microscope incorporated into the electron detecting means, the secondary electron detecting means is the first secondary electron detecting electrode 9 provided vertically above the sample 13.
And the second secondary electron detection electrode 18 provided in a partial area of the outer periphery of the first secondary electron detection electrode 9 achieves the above-described object. According to the invention of claim 7, the vacuum chamber 2 forming a passage of the primary electrons emitted from the electron beam source 1 and the vacuum chamber 2 are connected to each other through the pressure limiting opening 8, and the sample 13 is housed therein. Sample chamber 14 to be operated, vacuum evacuation means 15 for evacuating sample chamber 14, and sample chamber 1
A first electrode 9 provided so as to surround the pressure limiting opening 8 in the circumferential direction in the sample chamber 4 and a first electrode 9 in the sample chamber 14.
Second electrode 1 provided in a part of the outer periphery of the electrode 9 of
8, voltage sources 11 and 19 for applying a positive voltage to the sample 13 to the first electrode 9 and the second electrode 18, and a gas having an electron multiplying effect to the first electrode 9 and the first electrode 9 in the sample chamber 14, respectively. The above-described object is achieved by the scanning electron microscope provided with the gas supply unit 17 that is supplied between the second electrode 18 and the sample 13. Referring to FIGS. 6 and 7,
In the invention of claim 8, the vacuum chamber 2 forming the passage of the primary electrons emitted from the electron beam source 1 and the vacuum chamber 2 are connected to each other through the pressure limiting opening 8, and the sample 13 is housed therein. Sample chamber 14 to be evacuated, vacuum evacuation means 15 for evacuating the sample chamber 14, and a plurality of electrodes 22A, 2A provided inside the sample chamber 14 in a state of being electrically divided in the circumferential direction of the pressure limiting opening 8.
2B and a positive voltage with respect to the sample 13
Voltage sources 24A and 24B applied to A and 22B, and a plurality of electrodes 22 in the sample chamber 14 for supplying a gas having an electron multiplying effect.
Gas supply means 1 for supplying between A, 22B and the sample 13
The above-described object is achieved by the scanning electron microscope including the items 7 and 7.
【０００８】請求項１の発明によれば、試料１３を真上
から照明してそれを真上から観察したような２次電子信
号が第１の２次電子検出電極９にて検出される一方、第
２の２次電子検出電極１８では、試料１３を側方から照
明してそれを真上から観察したような２次電子信号が検
出される。この第２の２次電子検出電極１８の検出信号
には試料１３の凹凸を示す情報が含まれるから、これを
利用して凹凸感が強調された試料像を形成できる。請求
項２の発明によれば、複数の第１の２次電子検出電極２
２Ａ、２２Ｂが、１次電子のビーム軌道の周囲の互いに
異なる位置で２次電子を検出するから、各電極２２Ａ、
２２Ｂの検出信号のそれぞれに試料１３の凹凸を示す情
報が含まれるようになる。請求項３の発明によれば、第
１の２次電子検出電極９にて検出される２次電子信号
と、複数の第２の２次電子検出電極１８にて検出される
２次電子信号のうち、試料像の凹凸感を強調するために
適当な１又は２以上の信号を任意に選択できるようにな
る。請求項４の発明によれば、二種類の電極９、１８の
検出信号の加算の割合に応じて試料像の凹凸感を任意に
作り出せる。請求項５の発明によれば、複数の２次電子
検出電極２２Ａ、２２Ｂが、１次電子のビーム軌道の周
囲の互いに異なる位置で２次電子を検出するから、各電
極２２Ａ、２２Ｂの検出信号のそれぞれに試料１３の凹
凸を示す情報が含まれるようになる。請求項６の発明に
よれば、第１の２次電子検出電極９が作り出す電場によ
り、試料１３の真上で２次電子がガス増倍されて正イオ
ンが生成されるから、試料１３が絶縁体であってもこれ
を電気的に中和できる。第２の２次電子検出電極１８の
検出信号を利用して凹凸感のある試料像を形成できる。
請求項７の発明では、真空排気手段１５とガス供給手段
１７とによって電極９、１８と試料１３との間を低真空
のガス雰囲気に調整して電極９、１８に正電圧を印加し
た状態で、電子線源１から真空室２及び圧力制限開口８
を経て試料１３に１次電子を照射して２次電子を放出さ
せる。放出された２次電子は電極９、１８が作り出す電
場の下でガス増倍されて電極９、１８に取り込まれる。
第２の電極１８は試料１３の側方に位置するため、これ
に取り込まれた２次電子により凹凸感の強調された試料
像を形成できる。第１の電極９への正電圧の印加により
１次電子のビーム軌道の回りで２次電子がガス増倍され
て正イオンが生成され、その正イオンは容易に試料１３
に到達する。従って、試料１３が絶縁体であっても、こ
れを電気的に中和させることができる。第１の電極９に
取り込まれた２次電子も試料像の形成に利用できる。請
求項８の発明では、真空排気手段１５とガス供給手段１
７とによって電極９、１８と試料１３との間を低真空の
ガス雰囲気に調整して電極２２Ａ、２２Ｂに正電圧を印
加した状態で、電子線源１から真空室２及び圧力制限開
口８を経て試料１３に１次電子を照射して２次電子を放
出させる。放出された２次電子は電極２２Ａ、２２Ｂが
作り出す電場の下でガス増倍されて電極２２Ａ、２２Ｂ
に取り込まれる。各電極２２Ａ、２２Ｂが１次電子のビ
ーム軌道の周囲の互いに異なる位置に設けられるため、
これらに取り込まれた２次電子により凹凸感の強調され
た試料像を形成できる。電極２２Ａ、２２Ｂの作り出す
電場により１次電子のビーム軌道の回りで２次電子がガ
ス増倍されて正イオンが生成され、その正イオンは容易
に試料１３に到達する。従って、試料１３が絶縁体であ
っても、これを電気的に中和させることができる。According to the first aspect of the invention, the secondary electron signal as if the sample 13 is illuminated from directly above and observed from directly above is detected by the first secondary electron detection electrode 9. At the second secondary electron detection electrode 18, a secondary electron signal as if the sample 13 was illuminated from the side and observed from directly above is detected. Since the detection signal of the second secondary electron detection electrode 18 includes information indicating the unevenness of the sample 13, it is possible to form a sample image in which the feeling of unevenness is emphasized. According to the invention of claim 2, the plurality of first secondary electron detection electrodes 2
2A and 22B detect secondary electrons at different positions around the beam trajectory of the primary electrons, so that each electrode 22A,
Information indicating the unevenness of the sample 13 is included in each of the detection signals of 22B. According to the invention of claim 3, the secondary electron signal detected by the first secondary electron detection electrode 9 and the secondary electron signal detected by the plurality of second secondary electron detection electrodes 18 are detected. Among them, it becomes possible to arbitrarily select one or two or more signals suitable for enhancing the unevenness of the sample image. According to the invention of claim 4, the unevenness of the sample image can be arbitrarily created according to the ratio of addition of the detection signals of the two types of electrodes 9 and 18. According to the invention of claim 5, since the plurality of secondary electron detection electrodes 22A and 22B detect the secondary electrons at different positions around the beam trajectory of the primary electrons, the detection signals of the electrodes 22A and 22B are detected. The information indicating the unevenness of the sample 13 is included in each of the above. According to the invention of claim 6, since the secondary electrons are gas-multiplied directly above the sample 13 by the electric field created by the first secondary electron detection electrode 9 to generate positive ions, the sample 13 is insulated. Even the body can electrically neutralize this. By using the detection signal of the second secondary electron detection electrode 18, it is possible to form a sample image having a feeling of unevenness.
According to the invention of claim 7, a low vacuum gas atmosphere is adjusted between the electrodes 9 and 18 and the sample 13 by the vacuum exhaust means 15 and the gas supply means 17, and a positive voltage is applied to the electrodes 9 and 18. , Electron beam source 1 to vacuum chamber 2 and pressure limiting opening 8
After that, the sample 13 is irradiated with primary electrons to emit secondary electrons. The emitted secondary electrons are gas-multiplied under the electric field generated by the electrodes 9 and 18 and taken into the electrodes 9 and 18.
Since the second electrode 18 is located on the side of the sample 13, it is possible to form a sample image in which unevenness is emphasized by the secondary electrons taken in by the second electrode 18. By applying a positive voltage to the first electrode 9, the secondary electrons are gas-multiplied around the beam trajectory of the primary electrons to generate positive ions, and the positive ions are easily generated in the sample 13
To reach. Therefore, even if the sample 13 is an insulator, it can be electrically neutralized. The secondary electrons taken in by the first electrode 9 can also be used for forming a sample image. In the invention of claim 8, the vacuum exhaust means 15 and the gas supply means 1
In the state where a low-vacuum gas atmosphere is adjusted between the electrodes 9 and 18 and the sample 13 by 7 and a positive voltage is applied to the electrodes 22A and 22B, the vacuum chamber 2 and the pressure limiting opening 8 are opened from the electron beam source 1. After that, the sample 13 is irradiated with primary electrons to emit secondary electrons. The emitted secondary electrons are gas-multiplied under the electric field created by the electrodes 22A, 22B, and then the electrodes 22A, 22B.
Is taken into. Since the electrodes 22A and 22B are provided at different positions around the beam trajectory of the primary electron,
A sample image in which unevenness is emphasized can be formed by the secondary electrons taken in by these. Due to the electric field created by the electrodes 22A and 22B, the secondary electrons are gas-multiplied around the beam trajectory of the primary electrons to generate positive ions, and the positive ions easily reach the sample 13. Therefore, even if the sample 13 is an insulator, it can be electrically neutralized.
【０００９】なお、上記では本発明を分かり易くするた
めに実施の形態の図を参照したが、これにより本発明が
図示の形態に限定されるものではない。In the above description, the drawings of the embodiments are referred to in order to make the present invention easy to understand, but the present invention is not limited to the illustrated embodiments.
【００１０】[0010]
【発明の実施の形態】図１〜図１２を参照して本発明の
実施の形態を説明する。なお、各図において上述した図
１３〜図１５と共通する部分には同一符号を付し、説明
を省略する。図４及び図９では縦横軸の表示を省略した
が、それらは図１４と同じである。BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIGS. In addition, in each drawing, the same parts as those in FIGS. 13 to 15 described above are denoted by the same reference numerals, and description thereof will be omitted. Although the vertical and horizontal axes are omitted in FIGS. 4 and 9, they are the same as those in FIG.
【００１１】−第１の実施の形態− 図１は本発明の第１の実施の形態に係る環境制御型の走
査型電子顕微鏡の概略を、図２は図１の２次電子検出電
極を試料側から見上げた状態をそれぞれ示す。図１の電
子顕微鏡では、２次電子検出電極９の外側に別の２次電
子検出電極１８が設けられている。この２次電子検出電
極１８には、可変電圧源１９から試料１３に対する正の
電圧が印加される。図２から明らかなように、２次電子
検出電極９が圧力制限オリフィス８と同軸の一枚の円板
状であるのに対して、２次電子検出電極１８は電極９の
外周の一部のみに孤立的に設けられている。図１に示す
ように、各電極９、１８からの２次電子信号はプリアン
プ１２、２０にてそれぞれ増幅されて加算回路２１に入
力される。加算回路２１は両電極９、１８からの２次電
子信号を任意の割合で加算する。First Embodiment FIG. 1 is a schematic view of an environment control type scanning electron microscope according to the first embodiment of the present invention, and FIG. 2 shows a sample of the secondary electron detection electrode of FIG. Shown from the side, respectively. In the electron microscope of FIG. 1, another secondary electron detection electrode 18 is provided outside the secondary electron detection electrode 9. A positive voltage with respect to the sample 13 is applied from the variable voltage source 19 to the secondary electron detection electrode 18. As is apparent from FIG. 2, the secondary electron detection electrode 9 has a single disk shape coaxial with the pressure limiting orifice 8, whereas the secondary electron detection electrode 18 has only a part of the outer circumference of the electrode 9. It is provided independently. As shown in FIG. 1, the secondary electron signals from the electrodes 9 and 18 are respectively amplified by the preamplifiers 12 and 20 and input to the adder circuit 21. The adder circuit 21 adds the secondary electron signals from both electrodes 9 and 18 at an arbitrary ratio.
【００１２】図３に示すように、断面が台形状の試料１
３を図の左右方向に電子ビームで走査した場合、各２次
電子検出電極９、１８にて検出される２次電子信号は図
４の（ａ）及び（ｂ）にそれぞれ示したように変化す
る。これらを順に説明すると、図４（ａ）に示すよう
に、２次電子検出電極９では、試料１３の側面１３ａ、
１３ｃの位置（一点鎖線Ａ、Ｂの位置，図４（ｂ）、
（ｃ）も同じ。）でほぼ等しいピーク値を有する２次電
子信号が検出される。この点は図１４の例と同じであ
る。一方、２次電子検出電極１８では、これが試料１３
に対して特定方向（図示例では右方）に偏って配置され
ているため、２次電子検出電極９とは異なる信号が得ら
れる。すなわち、図５に示すように２次電子検出電極１
８に対して試料１３の左側面１３ａが逆方向を向くた
め、左側面１３ａから放出された２次電子ｓｅ１の少な
くとも一部は試料１３自身に遮られて２次電子検出器１
８には取り込まれない。従って、２次電子検出電極１８
にて検出される２次電子信号には、図４（ｂ）に示すよ
うに、左側面１３ａ側で小さいピーク値が、右側面１３
ｃ側で大きなピーク値がそれぞれ出現する。この状態
は、試料１３を右側方から照明しつつ真上から観察する
のに等しい。As shown in FIG. 3, sample 1 having a trapezoidal cross section
When 3 is scanned by an electron beam in the left-right direction in the figure, the secondary electron signals detected by the secondary electron detection electrodes 9 and 18 change as shown in FIGS. 4 (a) and 4 (b), respectively. To do. These will be described in order. As shown in FIG. 4A, in the secondary electron detection electrode 9, the side surface 13a of the sample 13
13c position (positions of alternate long and short dash lines A and B, FIG. 4 (b),
The same applies to (c). ), A secondary electron signal having a substantially equal peak value is detected. This point is the same as the example of FIG. On the other hand, in the secondary electron detection electrode 18, this is the sample 13
Since they are arranged in a specific direction (rightward in the illustrated example), a signal different from that of the secondary electron detection electrode 9 is obtained. That is, as shown in FIG. 5, the secondary electron detection electrode 1
Since the left side surface 13a of the sample 13 faces the opposite direction with respect to 8, at least a part of the secondary electrons se1 emitted from the left side surface 13a is blocked by the sample 13 itself and the secondary electron detector 1
Not taken into 8. Therefore, the secondary electron detection electrode 18
As shown in FIG. 4 (b), the secondary electron signal detected by the right side surface 13 has a small peak value on the left side surface 13 a side.
Large peak values appear on the c side. This state is equivalent to observing the sample 13 from directly above while illuminating the sample 13 from the right side.
【００１３】以上のように２次電子検出電極１８では試
料１３の側面の方向に応じて異なった２次電子信号が得
られるため、これを加算回路２１おいて２次電子検出電
極９からの信号に任意の割合で加算すれば、図４（ｃ）
に示すような２次電子信号が得られる。図４（ｃ）の例
では、右側面１３ｃ側のピーク値と左側面１３ａ側のピ
ーク値とに差が存在するため、ピーク値の大きい方を明
部に、低い方を暗部として処理すれば、凹凸感の強調さ
れた試料像が得られる。ピーク値の差は、加算回路２１
における加算の割合によって任意に変化させることがで
きる。２次電子検出電極１８にて検出された信号の割合
を大きくするほどピーク値の差が拡大する。二つの２次
電子信号の加算の割合を指示する指示装置を加算回路２
１に接続し、試料像の凹凸感が最も強調される最適な割
合をオペレータが選択できるようにするとよい。試料像
のコントラストを自動的に検出し、最適な割合を自動調
整するようにしてもよい。As described above, since the secondary electron detection electrode 18 obtains a different secondary electron signal depending on the direction of the side surface of the sample 13, this is added to the signal from the secondary electron detection electrode 9 in the adder circuit 21. If you add to the
A secondary electron signal as shown in is obtained. In the example of FIG. 4C, there is a difference between the peak value on the right side surface 13c side and the peak value on the left side surface 13a side. Therefore, if the larger peak value is processed as the bright area and the lower one is processed as the dark area, , A sample image in which unevenness is emphasized can be obtained. The peak value difference is calculated by the addition circuit 21.
It can be changed arbitrarily according to the ratio of addition in. The difference between the peak values increases as the ratio of the signal detected by the secondary electron detection electrode 18 increases. The adding circuit 2 is an indicating device that indicates the ratio of addition of two secondary electron signals.
It is preferable to connect to 1 so that the operator can select the optimum ratio at which the unevenness of the sample image is most emphasized. The contrast of the sample image may be automatically detected and the optimum ratio may be automatically adjusted.
【００１４】なお、図４（ｂ）から明らかなように、試
料１３に対して側方に位置する２次電子検出電極１８の
みで２次電子を検出した場合も凹凸感の強調は可能であ
る。しかしながら、その場合には２次電子検出電極１８
によって作り出される電場のみでガス増倍が行われるた
め、図５に示すようにガス増倍で生じる正イオンＰｉが
試料１３に降り注がず、試料１３が絶縁体の場合にその
帯電が中和されないおそれがある。従って、試料１３が
絶縁体のとき、電極９に対する正電圧の印加は必須であ
る。As is apparent from FIG. 4B, the unevenness can be emphasized even when the secondary electrons are detected only by the secondary electron detection electrodes 18 located laterally with respect to the sample 13. . However, in that case, the secondary electron detection electrode 18
Since gas multiplication is performed only by the electric field created by, the positive ions Pi generated by gas multiplication do not fall on the sample 13 as shown in FIG. 5, and the charge is neutralized when the sample 13 is an insulator. May not be performed. Therefore, when the sample 13 is an insulator, it is essential to apply a positive voltage to the electrode 9.
【００１５】−第２の実施の形態− 図６は本発明の第２の実施の形態に係る環境制御型の走
査型電子顕微鏡の概略を、図７は図６の２次電子検出電
極を試料側から見上げた状態をそれぞれ示す。なお、図
１及び図２と共通する部分には同一符号を付してある。
図６及び図７の走査型電子顕微鏡は、上述した図１の２
次電子検出電極９に代えて半円状の２枚の２次電子検出
電極２２Ａ、２２Ｂを設けたものである。電極２２Ａ、
２２Ｂの間には絶縁体２３が介装され、従って、両電極
２２Ａ、２２Ｂは電気的に分割されている。両電極２２
Ａ、２２Ｂには、試料１３に対する正の電圧が可変電圧
源２４Ａ、２４Ｂからそれぞれ印加される。電極１８、
２２Ａ、２２Ｂからの２次電子信号はプリアンプ２０、
２５Ａ、２５Ｂにてそれぞれ増幅されて加算回路２６に
入力される。加算回路２６は各電極２０、２５Ａ、２５
Ｂからの２次電子信号のうち、少なくとも２つの信号を
任意の割合で加算する。-Second Embodiment- FIG. 6 shows an outline of an environment control type scanning electron microscope according to a second embodiment of the present invention, and FIG. 7 shows a sample of the secondary electron detection electrode of FIG. Shown from the side, respectively. The same parts as those in FIGS. 1 and 2 are designated by the same reference numerals.
The scanning electron microscopes of FIGS. 6 and 7 are the same as those of FIG.
Instead of the secondary electron detection electrode 9, two semicircular secondary electron detection electrodes 22A and 22B are provided. Electrode 22A,
An insulator 23 is interposed between the electrodes 22B, so that the electrodes 22A and 22B are electrically separated. Both electrodes 22
A positive voltage with respect to the sample 13 is applied to A and 22B from variable voltage sources 24A and 24B, respectively. Electrode 18,
The secondary electron signals from 22A and 22B are supplied to the preamplifier 20,
The signals are amplified by 25A and 25B and input to the adding circuit 26. The adder circuit 26 includes electrodes 20, 25A, 25
Of the secondary electron signals from B, at least two signals are added at an arbitrary ratio.
【００１６】図８は、図３と同様の断面が台形状の試料
１３を電子ビームで走査した場合の各２次電子検出電極
２２Ａ、２２Ｂ、１８と試料１３から発生する２次電子
ｓｅ１〜ｓｅ３との関係を示し、この場合に電極２２
Ａ、２２Ｂ、１８にて検出される２次電子信号を図９の
（ａ）、（ｂ）及び（ｃ）にそれぞれ示す。なお、図９
の一点鎖線Ａは左側面１３ａの位置を、一点鎖線Ｂは右
側面１３ｃの位置をそれぞれ示す。試料１３の左側に偏
った２次電子検出電極２２Ａにて検出される２次電子信
号には、図９（ａ）に示すように、左側面１３ａの位置
で大きいピーク値が、右側面１３ｃの位置で小さいピー
ク値がそれぞれ出現する。反対に、試料１３の右側に偏
った２次電子検出電極２２Ｂにて検出される２次電子信
号には、図９（ｂ）に示すように、左側面１３ａの位置
で小さいピーク値が、右側面１３ｃの位置で大きなピー
ク値がそれぞれ出現する。電極１８で検出される２次電
子信号は図９（ｃ）の通りであり、これは図４（ｂ）の
例に等しい。FIG. 8 shows secondary electrons se1 to se3 generated from the secondary electron detection electrodes 22A, 22B, 18 and the sample 13 when the sample 13 having a trapezoidal cross section similar to that of FIG. 3 is scanned with an electron beam. , And in this case the electrode 22
The secondary electron signals detected at A, 22B and 18 are shown in FIGS. 9A, 9B and 9C, respectively. Note that FIG.
An alternate long and short dash line A indicates the position of the left side surface 13a, and an alternate long and short dash line B indicates the position of the right side surface 13c. As shown in FIG. 9A, the secondary electron signal detected by the secondary electron detection electrode 22A that is biased to the left side of the sample 13 has a large peak value at the position of the left side surface 13a as shown in FIG. 9A. A small peak value appears at each position. On the contrary, in the secondary electron signal detected by the secondary electron detection electrode 22B, which is biased to the right side of the sample 13, as shown in FIG. Large peak values appear at the position of the surface 13c. The secondary electron signal detected by the electrode 18 is as shown in FIG. 9C, which is equivalent to the example of FIG. 4B.
【００１７】以上の２次電子検出信号に対して、例えば
電極２２Ａの信号から電極２２Ｂの信号を１：−１の比
率で加算、換言すれば電極２２Ａの信号から電極２２Ｂ
の信号を１：１の比率で減算すると図９（ｄ）に示す２
次電子信号が得られる。この信号では、左側面１３ａの
位置で正のピーク値が、右側面１３ｃで負のピーク値が
それぞれ出現している。従って、図４（ｃ）の例にも増
して試料像の凹凸を強調できる。なお、電極２２Ａ、２
２Ｂにて検出した信号を加算する例に限らず、３つの２
次電子信号のうち少なくとも２つの信号を選択し、任意
の割合で加算してよい。加算処理の内容を指示する入力
装置を加算回路２６に接続し、試料を観察する毎にオペ
レータが最適な処理を選択できるようにするとよい。処
理内容を変化させつつ試料像のコントラストを自動的に
検出して最適な処理を自動的に選択するようにしてもよ
い。For example, the signal from the electrode 22A to the signal from the electrode 22B is added to the secondary electron detection signal at a ratio of 1: -1, that is, from the signal from the electrode 22A to the electrode 22B.
When the signal of 1 is subtracted at a ratio of 1: 1, 2 shown in FIG.
A secondary electron signal is obtained. In this signal, a positive peak value appears at the position of the left side surface 13a and a negative peak value appears at the right side surface 13c. Therefore, the unevenness of the sample image can be emphasized more than in the example of FIG. The electrodes 22A, 2
It is not limited to the example in which the signals detected in 2B are added, and three 2
At least two signals of the next electronic signals may be selected and added at an arbitrary ratio. An input device for instructing the content of the addition process may be connected to the addition circuit 26 so that the operator can select the optimum process each time the sample is observed. The optimum processing may be automatically selected by automatically detecting the contrast of the sample image while changing the processing content.
【００１８】−第３の実施の形態− 図１０は本発明の第３の実施の形態に係る環境制御型の
走査型電子顕微鏡の概略を、図１１は図１０の２次電子
検出電極を試料側から見上げた状態をそれぞれ示す。な
お、図１及び図２と共通する部分には同一符号を付して
ある。図１０及び図１１の走査型電子顕微鏡は、２次電
子検出電極９の外周を４等分する位置に２次電子検出電
極１８をそれぞれ１つずつ合計４個設けたものである。
各電極１８には１：１に対応させて可変電圧源１９が接
続される。それぞれの可変電圧源１９から各電極１３に
は試料１３に対する正の電圧が印加される。各電極９、
１８にて検出された２次電子信号はプリアンプ１２、２
０にてそれぞれ増幅されて加算回路２７に入力される。
加算回路２７は、単一の２次電子検出電極９と、４つの
２次電子検出電極１８の合計５つの電極からの２次電子
信号のうち、少なくとも２つの信号を任意の割合で加算
して試料像の凹凸感を強調する。加算処理の内容は、図
６の例と同様にオペレータが適宜選択できるようにする
とよい。なお、２次電子検出電極１８は、２次電子検出
電極９の外周を４等分する位置に限らず、２以上の任意
の位置に設けることができる。この形態でも、加算回路
２７の処理内容をオペレータにより選択可能とし、ある
いは自動調整可能とすることが好ましい。-Third Embodiment- FIG. 10 is a schematic view of an environment control type scanning electron microscope according to a third embodiment of the present invention, and FIG. 11 shows a sample of the secondary electron detection electrode of FIG. Shown from the side, respectively. The same parts as those in FIGS. 1 and 2 are designated by the same reference numerals. The scanning electron microscopes of FIGS. 10 and 11 are each provided with four secondary electron detection electrodes 18 at a position where the outer periphery of the secondary electron detection electrode 9 is divided into four equal parts in total.
A variable voltage source 19 is connected to each electrode 18 in a 1: 1 correspondence. A positive voltage with respect to the sample 13 is applied from each variable voltage source 19 to each electrode 13. Each electrode 9,
The secondary electron signals detected at 18 are preamplifiers 12, 2
Each signal is amplified by 0 and input to the adder circuit 27.
The adder circuit 27 adds at least two signals among the secondary electron signals from the single secondary electron detection electrode 9 and the total of five secondary electron detection electrodes 18 at an arbitrary ratio. The unevenness of the sample image is emphasized. The content of the addition process may be appropriately selected by the operator as in the example of FIG. The secondary electron detection electrode 18 is not limited to a position where the outer circumference of the secondary electron detection electrode 9 is divided into four equal parts, and can be provided at any position of two or more. Also in this form, it is preferable that the processing content of the adding circuit 27 can be selected by an operator or can be automatically adjusted.
【００１９】図１〜図１１の形態では、圧力制限オリフ
ィス８を取り囲むように配置された電極９、２２Ａ、２
２Ｂと、それよりも外側の電極１８とを組合わせたが本
発明はそのような形態に限らない。図９（ｄ）の例から
明らかなように、２次電子検出電極１８の検出信号を用
いなくても試料像の凹凸感を形成することは可能である
から、例えば図１２（ａ）に示すように圧力制限オリフ
ィス８の回りに絶縁体３０にて分割された複数の電極３
１Ａ、３１Ｂ、３１Ｃ、３１Ｄを設けるだけでもよい。
この場合も電極の数は４個に限らない。さらに、図１２
（ｂ）に示したように、電極３１Ａ〜３１Ｄの外側に電
極１８を複数設けてもよい。この例では、電極３１Ａ〜
３１Ｄの分割位置と電極１８の位置とを合せてあるが、
そのような形態に限らないことは勿論である。複数の電
極にて検出された２次電子信号を記憶装置に一旦記憶さ
せ、試料の走査が終了した後に最適な加算処理を探索す
るようにしてもよい。In the embodiment of FIGS. 1 to 11, the electrodes 9, 22A, 2 arranged to surround the pressure limiting orifice 8 are shown.
Although 2B and the electrode 18 outside thereof are combined, the present invention is not limited to such a form. As is clear from the example of FIG. 9D, it is possible to form the unevenness of the sample image without using the detection signal of the secondary electron detection electrode 18, and therefore, for example, as shown in FIG. Electrodes 3 divided by insulator 30 around pressure limiting orifice 8
Only 1A, 31B, 31C and 31D may be provided.
Also in this case, the number of electrodes is not limited to four. Further, FIG.
As shown in (b), a plurality of electrodes 18 may be provided outside the electrodes 31A to 31D. In this example, the electrodes 31A to
Although the division position of 31D and the position of the electrode 18 are aligned,
Of course, it is not limited to such a form. The secondary electron signals detected by the plurality of electrodes may be temporarily stored in the storage device, and the optimum addition processing may be searched for after the scanning of the sample is completed.
【００２０】以上の形態では、２次電子検出電極９、２
２Ａ、２２Ｂ、３１Ａ、３１Ｂ、３１Ｃ、３１Ｄが第１
の２次電子検出電極及び第１の電極を、２次電子検出電
極１８が第２の２次電子検出電極及び第２の電極を、加
算回路２１、２６、２７が処理回路を、圧力制限オリフ
ィス８が圧力制限開口を、真空ポンプ１５が真空排気手
段を、気体供給源１７がガス供給手段を、それぞれ構成
する。なお、加算回路２１、２６、２７にて複数の電極
からの２次電子信号を加算せず、試料の凹凸感を最も強
調できるいずれか一つの２次電子信号により試料像を形
成してもよい。In the above embodiment, the secondary electron detection electrodes 9 and 2 are
2A, 22B, 31A, 31B, 31C, 31D are first
Of the secondary electron detection electrode and the first electrode, the secondary electron detection electrode 18 of the second secondary electron detection electrode and the second electrode, the adding circuits 21, 26 and 27 of the processing circuit, and the pressure limiting orifice. Reference numeral 8 constitutes a pressure limiting opening, vacuum pump 15 constitutes a vacuum exhaust means, and gas supply source 17 constitutes a gas supply means. It should be noted that the sample images may be formed by any one of the secondary electron signals that can most emphasize the unevenness of the sample without adding the secondary electron signals from the plurality of electrodes in the adding circuits 21, 26, and 27. .
【００２１】[0021]
【発明の効果】以上説明したように、本発明によれば、
１次電子のビーム軌道の周囲の互いに異なる位置に設け
られた複数の２次電子検出電極にて２次電子を検出可能
としたので、試料像の凹凸感を強調してその観察を行う
ことができる。As described above, according to the present invention,
Since the secondary electrons can be detected by a plurality of secondary electron detection electrodes provided at different positions around the beam trajectory of the primary electrons, the unevenness of the sample image can be emphasized for observation. it can.
【図１】本発明の第１の実施の形態に係る走査型電子顕
微鏡の概略を示す図。FIG. 1 is a diagram showing an outline of a scanning electron microscope according to a first embodiment of the present invention.
【図２】図１の２次電子検出電極を試料側から見上げた
状態を示す図。FIG. 2 is a diagram showing a state in which the secondary electron detection electrode of FIG. 1 is looked up from the sample side.
【図３】図１の走査型電子顕微鏡により断面が台形状の
試料を観察するときの２次電子と２次電子検出電極との
関係を示す図。3 is a diagram showing the relationship between secondary electrons and secondary electron detection electrodes when observing a sample having a trapezoidal cross section with the scanning electron microscope of FIG.
【図４】図３の観察時に２次電子検出電極にて検出され
る２次電子信号と、それらを加算処理した信号とを示す
図。FIG. 4 is a diagram showing a secondary electron signal detected by a secondary electron detection electrode at the time of observation in FIG. 3 and a signal obtained by adding them.
【図５】図３において試料の側方に配置された２次電子
検出電極に２次電子が取り込まれるときの様子を示す
図。FIG. 5 is a diagram showing a state when secondary electrons are taken in by a secondary electron detection electrode arranged on the side of the sample in FIG.
【図６】本発明の第２の実施の形態に係る走査型電子顕
微鏡の概略を示す図。FIG. 6 is a diagram showing an outline of a scanning electron microscope according to a second embodiment of the present invention.
【図７】図６の２次電子検出電極を試料側から見上げた
状態を示す図。FIG. 7 is a diagram showing a state in which the secondary electron detection electrode of FIG. 6 is looked up from the sample side.
【図８】図６の走査型電子顕微鏡により断面が台形状の
試料を観察するときの２次電子と２次電子検出電極との
関係を示す図。8 is a diagram showing the relationship between secondary electrons and secondary electron detection electrodes when observing a sample having a trapezoidal cross section with the scanning electron microscope of FIG.
【図９】図８の観察時に２次電子検出電極にて検出され
る２次電子信号と、それらを加算処理した信号とを示す
図。9 is a diagram showing a secondary electron signal detected by a secondary electron detection electrode during the observation of FIG. 8 and a signal obtained by adding them.
【図１０】本発明の第３の実施の形態に係る走査型電子
顕微鏡の概略を示す図。FIG. 10 is a diagram schematically showing a scanning electron microscope according to a third embodiment of the invention.
【図１１】図１０の２次電子検出電極を試料側から見上
げた状態を示す図。11 is a diagram showing a state in which the secondary electron detection electrode of FIG. 10 is looked up from the sample side.
【図１２】図２、図７、図１１を変形した形態を示す
図。FIG. 12 is a view showing a modified form of FIGS. 2, 7, and 11.
【図１３】従来の環境制御型の走査型電子顕微鏡の概略
を示す図。FIG. 13 is a view showing an outline of a conventional environment control type scanning electron microscope.
【図１４】図１３の走査型電子顕微鏡により断面が台形
状の試料を観察するときの２次電子と２次電子検出電極
との関係を示す図。14 is a diagram showing the relationship between secondary electrons and secondary electron detection electrodes when observing a sample having a trapezoidal cross section with the scanning electron microscope of FIG.
【図１５】図１４の観察時に２次電子検出電極にて検出
される２次電子信号を示す図。15 is a diagram showing a secondary electron signal detected by a secondary electron detection electrode during the observation of FIG.
２ 真空室 ８ 圧力制限オリフィス ９，１８，２２Ａ，２２Ｂ，３１Ａ，３１Ｂ，３１Ｃ，
３１Ｄ ２次電子検出電極 １３ 試料 １４ 試料室 １５ 真空ポンプ １７ 気体供給源 ２１，２６，２７ 加算回路 ｓｅ１，ｓｅ２，ｓｅ３ ２次電子2 vacuum chamber 8 pressure limiting orifice 9, 18, 22A, 22B, 31A, 31B, 31C,
31D Secondary electron detection electrode 13 Sample 14 Sample chamber 15 Vacuum pump 17 Gas supply sources 21, 26, 27 Adder circuit se1, se2, se3 Secondary electron
Claims (8)
した２次電子を低真空のガス雰囲気中で増倍して２次電
子検出手段に取り込む走査型電子顕微鏡において、 前記２次電子検出手段は、前記１次電子のビーム軌道を
取り囲むように設けられる第１の２次電子検出電極と、
前記第１の２次電子検出電極の外周の一部の領域に設け
られる第２の２次電子検出電極と、を有することを特徴
とする走査型電子顕微鏡。1. A scanning electron microscope in which secondary electrons generated from a sample in response to irradiation of primary electrons are multiplied in a low-vacuum gas atmosphere and taken into a secondary electron detection means. The detection means includes a first secondary electron detection electrode provided so as to surround the beam trajectory of the primary electron,
And a second secondary electron detection electrode provided in a partial area on the outer periphery of the first secondary electron detection electrode.
て、 前記第１の２次電子検出電極が、前記ビーム軌道の周方
向に電気的に分割された状態で複数設けられていること
を特徴とする走査型電子顕微鏡。2. The scanning electron microscope according to claim 1, wherein a plurality of the first secondary electron detection electrodes are provided in a state of being electrically divided in the circumferential direction of the beam orbit. Scanning electron microscope.
て、 前記第２の２次電子検出電極が、前記ビーム軌道の周方
向に複数設けられていることを特徴とする走査型電子顕
微鏡。3. The scanning electron microscope according to claim 1, wherein a plurality of the second secondary electron detection electrodes are provided in the circumferential direction of the beam orbit.
て、 前記第１の２次電子検出電極にて検出された２次電子信
号と、前記第２の２次電子検出電極にて検出された２次
電子信号とを所定の割合で加算する処理回路を備えるこ
とを特徴とする走査型電子顕微鏡。4. The scanning electron microscope according to claim 1, wherein the secondary electron signal detected by the first secondary electron detection electrode and the secondary electron signal detected by the second secondary electron detection electrode. A scanning electron microscope, comprising a processing circuit for adding a secondary electron signal at a predetermined ratio.
した２次電子を低真空のガス雰囲気中で増倍して２次電
子検出電極に取り込む走査型電子顕微鏡において、 前記２次電子検出電極が、前記ビーム軌道の周方向に電
気的に分割された状態で複数設けられていることを特徴
とする走査型電子顕微鏡。5. A scanning electron microscope in which secondary electrons generated from a sample in response to irradiation with primary electrons are multiplied in a low vacuum gas atmosphere and taken into a secondary electron detection electrode, wherein the secondary electrons are A scanning electron microscope, wherein a plurality of detection electrodes are provided in a state of being electrically divided in the circumferential direction of the beam orbit.
した２次電子を低真空のガス雰囲気中で増倍して２次電
子検出手段に取り込む走査型電子顕微鏡において、 前記２次電子検出手段は、前記試料の鉛直上方に設けら
れる第１の２次電子検出電極と、前記第１の２次電子検
出電極の外周の一部の領域に設けられる第２の２次電子
検出電極と、を有することを特徴とする走査型電子顕微
鏡。6. A scanning electron microscope in which secondary electrons generated from a sample in response to irradiation of primary electrons are multiplied in a low-vacuum gas atmosphere and taken into secondary electron detection means. The detection means includes a first secondary electron detection electrode provided vertically above the sample, and a second secondary electron detection electrode provided in a part of the outer circumference of the first secondary electron detection electrode. And a scanning electron microscope.
を形成する真空室と、 前記真空室に圧力制限開口を介して連設され、内部には
試料が収納される試料室と、 前記試料室を真空排気する真空排気手段と、 前記試料室内において前記圧力制限開口を周方向に取り
囲むように設けられる第１の電極と、 前記試料室内において前記第１の電極の外周の一部の領
域に設けられる第２の電極と、 前記試料に対する正の電圧を前記第１の電極及び前記第
２の電極に印加する電圧源と、 電子増倍作用を有するガスを前記試料室内の前記第１の
電極及び第２の電極と前記試料との間に供給するガス供
給手段と、を具備する走査型電子顕微鏡。7. A vacuum chamber that forms a passage for primary electrons emitted from an electron beam source, a sample chamber that is connected to the vacuum chamber via a pressure limiting opening, and stores a sample therein. Vacuum evacuation means for evacuating the sample chamber; a first electrode provided so as to surround the pressure limiting opening in the sample chamber in the circumferential direction; and a part of the outer periphery of the first electrode in the sample chamber. A second electrode provided in the region, a voltage source for applying a positive voltage to the sample to the first electrode and the second electrode, and a gas having an electron multiplication effect to the first electrode in the sample chamber. And a gas supply means for supplying the gas between the second electrode and the sample.
を形成する真空室と、 前記真空室に圧力制限開口を介して連設され、内部には
試料が収納される試料室と、 前記試料室を真空排気する真空排気手段と、 前記圧力制限開口の周方向に電気的に分割された状態で
前記試料室内に設けられる複数の電極と、 前記試料に対する正の電圧を前記複数の電極に印加する
電圧源と、 電子増倍作用を有するガスを前記試料室内の前記複数の
電極と前記試料との間に供給するガス供給手段と、を具
備する走査型電子顕微鏡。8. A vacuum chamber which forms a passage for primary electrons emitted from an electron beam source, a sample chamber which is connected to the vacuum chamber via a pressure limiting opening, and in which a sample is stored. Vacuum evacuation means for evacuating the sample chamber; a plurality of electrodes provided in the sample chamber in a state of being electrically divided in the circumferential direction of the pressure limiting opening; a positive voltage for the sample; A scanning electron microscope, comprising: a voltage source applied to the sample; and a gas supply unit that supplies a gas having an electron multiplying effect between the plurality of electrodes in the sample chamber and the sample.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7202347A JPH0950781A (en) | 1995-08-08 | 1995-08-08 | Scanning electron microscope |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7202347A JPH0950781A (en) | 1995-08-08 | 1995-08-08 | Scanning electron microscope |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0950781A true JPH0950781A (en) | 1997-02-18 |
Family
ID=16456035
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7202347A Pending JPH0950781A (en) | 1995-08-08 | 1995-08-08 | Scanning electron microscope |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0950781A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20030080375A (en) * | 2002-04-08 | 2003-10-17 | 삼성전자주식회사 | Scanning electron microscope(SEM) with a cylindrical secondary electron detecter |
| JP2008117690A (en) * | 2006-11-07 | 2008-05-22 | Hitachi High-Technologies Corp | Gas amplification type detector and electron beam application device using it |
-
1995
- 1995-08-08 JP JP7202347A patent/JPH0950781A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20030080375A (en) * | 2002-04-08 | 2003-10-17 | 삼성전자주식회사 | Scanning electron microscope(SEM) with a cylindrical secondary electron detecter |
| JP2008117690A (en) * | 2006-11-07 | 2008-05-22 | Hitachi High-Technologies Corp | Gas amplification type detector and electron beam application device using it |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4785182A (en) | Secondary electron detector for use in a gaseous atmosphere | |
| US7755045B2 (en) | Scanning electron microscope | |
| JP2794471B2 (en) | electronic microscope | |
| JP6047508B2 (en) | Charged particle beam apparatus, sample image acquisition method, and program recording medium | |
| EP0444085A4 (en) | Improved electron detector for use in a gaseous environment | |
| WO2020084729A1 (en) | Charged particle beam device, autofocus processing method for charged particle beam device, and detector | |
| JP2002289129A (en) | Electron microscope being scanned at low degree of vacuum | |
| JPH1196956A (en) | Scanning electron microscope | |
| JP2003157789A (en) | Cathodoluminescence detection device for scanning electron microscope or the like | |
| US6281496B1 (en) | Observing/forming method with focused ion beam and apparatus therefor | |
| JPH0950781A (en) | Scanning electron microscope | |
| JP6097863B2 (en) | Charged particle beam apparatus, sample image acquisition method, and program recording medium | |
| JPH10134751A (en) | Scanning electron microscope of environmental control type | |
| JPH0963525A (en) | Scanning electron microscope | |
| US4107527A (en) | Ion-emission microanalyzer microscope | |
| JPH06338280A (en) | Environmental control type scanning electron microscope | |
| JP2001126655A5 (en) | ||
| JPH05234552A (en) | Scanning electron microscope | |
| JPH0660841A (en) | Scanning type electron microscope | |
| JPH024441Y2 (en) | ||
| JPH04229939A (en) | Electron beam device | |
| JPH10283962A (en) | Environment control type scanning transmission electron beam observation device | |
| JPH06338282A (en) | Scanning electron microscope | |
| JPH11167891A (en) | Scanning electron microscope apparatus | |
| JP2003197143A (en) | Low-vacuum scanning electron microscope |