JPH08329872A - Electrostatic lens and its manufacture - Google Patents
Electrostatic lens and its manufactureInfo
- Publication number
- JPH08329872A JPH08329872A JP13806095A JP13806095A JPH08329872A JP H08329872 A JPH08329872 A JP H08329872A JP 13806095 A JP13806095 A JP 13806095A JP 13806095 A JP13806095 A JP 13806095A JP H08329872 A JPH08329872 A JP H08329872A
- Authority
- JP
- Japan
- Prior art keywords
- resistance material
- columnar body
- electrostatic lens
- low
- hole
- 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
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は電子顕微鏡や電子・イオ
ンビーム応用装置に用いる静電レンズおよびその製造方
法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic lens used in an electron microscope or an electron / ion beam application device, and a method of manufacturing the same.
【０００２】[0002]
【従来の技術】静電レンズは従来、電子顕微鏡などの電
子銃レンズやイオンビーム装置の集束レンズとして用い
られてきた。2. Description of the Related Art Electrostatic lenses have hitherto been used as electron gun lenses for electron microscopes and as focusing lenses for ion beam devices.
【０００３】従来の代表的な電子ビーム用円筒型静電レ
ンズ概略とその光線図を図４に示す。FIG. 4 shows an outline of a typical conventional cylindrical electrostatic lens for electron beam and its ray diagram.
【０００４】図６において、符号１００は電子銃の位置
を示し、電子ビーム１０１はこの電子銃の位置１００か
らある開き角をもって出射され、試料１０２上で結像す
る。第１電極１０３はアース１０４に接地され、中央の
第２電極１０５はレンズ電界を形成する負電位の電源１
０６に接続され、また第３電極１０７はアース１０４に
接地されている。In FIG. 6, reference numeral 100 indicates the position of the electron gun, and the electron beam 101 is emitted from the position 100 of the electron gun with a certain opening angle and forms an image on the sample 102. The first electrode 103 is grounded to the earth 104, and the second electrode 105 at the center is a negative potential power source 1 that forms a lens electric field.
06, and the third electrode 107 is grounded to the ground 104.
【０００５】図６に示すような構成の静電レンズ１０８
は、一般にアインツェルレンズと呼ばれており、３枚の
電極１０３，１０５，１０７から構成されている。この
ように静電レンズ１０８は円筒形あるいは円盤型などの
電極１０３，１０５，１０７を複数枚組み合わせて作成
される。電源１０６から第２電極１０５に電圧が印加さ
れると、試料台１０２に電子ビームが結像する。この静
電レンズ１０８の電位分布を図７に示す。図７に示すよ
うに第２電極１０５に電位のピーク（−ＶＰ）が生じ、
第１および第３電極１０３，１０７に向かって零電位に
近づいていく。なお、一般的には零電位ではなく加速電
圧相当のオフセットをもつことが多い。An electrostatic lens 108 having a structure as shown in FIG.
Is generally called an Einzel lens, and is composed of three electrodes 103, 105 and 107. In this way, the electrostatic lens 108 is formed by combining a plurality of electrodes 103, 105, 107 having a cylindrical shape or a disk shape. When a voltage is applied from the power supply 106 to the second electrode 105, an electron beam is imaged on the sample stage 102. The potential distribution of this electrostatic lens 108 is shown in FIG. As shown in FIG. 7, a peak of the potential (−VP) is generated in the second electrode 105,
It approaches zero potential toward the first and third electrodes 103, 107. In addition, in general, the offset is not zero potential and is often equivalent to the acceleration voltage.
【０００６】図８に静電レンズ１１０の具体的な構成例
を示す。図８に示す静電レンズ１１０は電極を非対称に
すること、すなわち軸上電位分布を非対称にすることで
収差低減が図られたもので、非対称アイツェルレンズと
呼ばれるものである。図６と同じように第１電極１１１
はアース電位に、中央第２電極１１２はレンズ電界を形
成する負電位に、第３電極１１３はアース電位に維持さ
れている。第２電極１１２に印加する電圧はビームの種
類により異なる。図８において各電極１１１，１１２，
１１３は絶縁のためにセラミックホルダ１１４に保持さ
れている。FIG. 8 shows a specific configuration example of the electrostatic lens 110. The electrostatic lens 110 shown in FIG. 8 has an asymmetric electrode, that is, an asymmetric axial electric potential distribution to reduce aberrations, and is called an asymmetric Aitzel lens. Similar to FIG. 6, the first electrode 111
Is maintained at a ground potential, the central second electrode 112 is maintained at a negative potential forming a lens electric field, and the third electrode 113 is maintained at a ground potential. The voltage applied to the second electrode 112 depends on the type of beam. In FIG. 8, each electrode 111, 112,
113 is held by a ceramic holder 114 for insulation.
【０００７】図６および図８に示す静電レンズ１０８、
１１０において、電子銃の位置１００から出射された電
子ビーム１０１は、静電レンズ１０８、１１０を経て試
料台１０２に結像するようになっている。The electrostatic lens 108 shown in FIGS. 6 and 8,
At 110, the electron beam 101 emitted from the position 100 of the electron gun forms an image on the sample stage 102 via the electrostatic lenses 108 and 110.
【０００８】また、図８に示すように、静電レンズ１１
０の各電極１１１，１１２，１１３は絶縁体であるセラ
ミックホルダ１１４により保持固定されている。そして
各電極１１１，１１２，１１３間は同軸度、同心度とも
に約１０μｍという精度でセラミックホルダ１１４によ
り保たれている。Further, as shown in FIG. 8, the electrostatic lens 11
The respective electrodes 111, 112, 113 of No. 0 are held and fixed by the ceramic holder 114 which is an insulator. The electrodes 111, 112, 113 are held by the ceramic holder 114 with accuracy of about 10 μm in both coaxiality and concentricity.
【０００９】また、中心軸上からセラミックホルダ１１
４が直接みえないように各電極１１１，１１２，１１３
の形状は決定されており、これによって帯電を防止でき
るようになっている。なお、図６に示す静電レンズ１０
８においても、各電極１０３，１０５，１０７は、図示
しないセラミックホルダにより保持固定されている。図
１０に、静電レンズの同軸度とレンズ性能を決定するビ
ーム径ぼけ率（ビーム径ぼけ量／ビーム径ｘ１００％）
との関係を示す。ビーム径は分解能に相当し、図１０か
ら同軸精度が劣化していくとビーム径ぼけ量が増加し分
解能が低下していくことがわかる。Further, from the center axis, the ceramic holder 11
Each electrode 111, 112, 113 so that 4 cannot be seen directly
The shape of has been determined, and this makes it possible to prevent charging. The electrostatic lens 10 shown in FIG.
Also in 8, the electrodes 103, 105 and 107 are held and fixed by a ceramic holder (not shown). FIG. 10 shows the beam diameter blur ratio (beam diameter blur amount / beam diameter × 100%) that determines the coaxiality of the electrostatic lens and the lens performance.
Shows the relationship with. The beam diameter corresponds to the resolution, and it can be seen from FIG. 10 that the beam diameter blur amount increases and the resolution decreases as the coaxial accuracy deteriorates.
【００１０】[0010]
【発明が解決しようとする課題】従来図６や図８に示す
従来の静電レンズ１０８、１１０においては、静電レン
ズを構成する個々の部品自身は高精度に製造されていて
も、以下に述べるように部品を組み合わせることによ
り、同軸度の精度が低くならざるを得なかった。Conventionally, in the conventional electrostatic lenses 108 and 110 shown in FIG. 6 and FIG. 8, even if the individual parts constituting the electrostatic lens are manufactured with high precision, By combining the parts as described, the precision of the coaxiality was unavoidable.
【００１１】図１０に示す静電レンズ１１０において、
セラミックホルダ１１４等により複数枚、例えば３枚の
電極１１１、１１２、１１３が保持固定されている。In the electrostatic lens 110 shown in FIG. 10,
A plurality of, for example, three electrodes 111, 112, 113 are held and fixed by a ceramic holder 114 or the like.
【００１２】しかしながら、複数枚の電極１１１、１１
２、１１３をセラミックホルダ１１４により保持固定す
る場合、電子ビームの中心軸に対して各々の電極１１
１、１１２、１１３を精度良く配置する作業は煩雑で、
組み立てが容易でない。However, a plurality of electrodes 111, 11
When 2 and 113 are held and fixed by the ceramic holder 114, each electrode 11 is attached to the center axis of the electron beam.
The work of accurately arranging 1, 112, 113 is complicated,
Not easy to assemble.
【００１３】また、図８に示す静電レンズ１１０の場
合、セラミックホルダ１１４内の帯電防止とレンズ収差
減少を目的として各々の電極１１１、１１２、１１３は
複雑な形状に形成されている。すなわち、帯電防止する
ためには、電子ビーム軌道上からからセラミックホルダ
１１４の壁面を見えないようにする必要があり、このた
めに電極１１１、１１２、１１３は互いに重なりあうよ
うな形状にする必要がある。また、帯電防止するととと
もにレンズ収差を減少させる必要もあり、各電極の形状
はさらに複雑になる。各電極１１１、１１２、１１３の
形状を複雑化させると、これに合わせてセラミックホル
ダ１１４の形状も複雑化し、静電レンズ１１０の全体形
状が大型化してしまう。このため製作が容易でなくコス
ト高になるという問題があった。Further, in the case of the electrostatic lens 110 shown in FIG. 8, each electrode 111, 112, 113 is formed in a complicated shape for the purpose of preventing charging in the ceramic holder 114 and reducing lens aberration. That is, in order to prevent electrostatic charge, it is necessary to make the wall surface of the ceramic holder 114 invisible from the orbit of the electron beam, and for this reason, the electrodes 111, 112, 113 need to be shaped so as to overlap each other. is there. In addition, it is necessary to prevent lens charging and reduce lens aberrations, which further complicates the shape of each electrode. If the shape of each electrode 111, 112, 113 is complicated, the shape of the ceramic holder 114 is also complicated accordingly, and the overall shape of the electrostatic lens 110 is increased. Therefore, there is a problem that manufacturing is not easy and the cost is high.
【００１４】そこで本発明の目的は、上記従来技術の有
する問題を解消し、加工および組み立てを容易に行うこ
とができレンズ精度を向上させた静電レンズおよびその
製造方法を提供することである。SUMMARY OF THE INVENTION An object of the present invention is to provide an electrostatic lens which solves the above problems of the prior art, can be easily processed and assembled, and has improved lens precision, and a method of manufacturing the same.
【００１５】[0015]
【課題を解決するための手段】上記目的を達成するため
に、本発明による静電レンズの製造方法は、荷電粒子ビ
ームを発散あるいは収束させるための静電レンズの製造
方法において、絶縁性筒体の挿入貫通孔に高抵抗材柱状
体と低抵抗材柱状体とを互いに隙間なく交互に挿入し、
前記低抵抗材柱状体と前記高抵抗材柱状体とを前記絶縁
性筒体に一体化させた状態で前記低抵抗材柱状体および
前記高抵抗材柱状体に前記荷電粒子ビームが伝播する伝
播貫通孔を形成することを特徴とする。In order to achieve the above object, the method of manufacturing an electrostatic lens according to the present invention is the method of manufacturing an electrostatic lens for diverging or converging a charged particle beam, comprising an insulating cylindrical body. Insert the high-resistance material columnar body and the low-resistance material columnar body alternately into the insertion through-hole without any gap,
Propagation penetration in which the charged particle beam propagates to the low resistance material columnar body and the high resistance material columnar body in a state where the low resistance material columnar body and the high resistance material columnar body are integrated with the insulating cylinder. It is characterized by forming holes.
【００１６】好適には、前記高抵抗材柱状体と前記低抵
抗材柱状体とは、各々少なくとも１個以上挿入されてい
る。Preferably, at least one or more high-resistance material columnar bodies and at least one low-resistance material columnar body are inserted.
【００１７】好適には、前記低抵抗材柱状体は金属材か
らなり、前記高抵抗材柱状体はＳｉＣ材からなる。Preferably, the low resistance material columnar body is made of a metal material, and the high resistance material columnar body is made of a SiC material.
【００１８】好適には、前記低抵抗材柱状体は低抵抗率
の成分比率を有するＳｉＣ材からなり、前記高抵抗材柱
状体は高抵抗率の成分比率を有するＳｉＣ材からなる。Preferably, the low-resistance material columnar body is made of a SiC material having a low resistivity component ratio, and the high-resistance material columnar body is made of a SiC material having a high resistivity component ratio.
【００１９】好適には、前記挿入貫通孔に、低抵抗率を
与える成分比率を有する低抵抗柱状部分と高抵抗率を与
える成分比率を有する高抵抗柱状部分とが長手方向に所
定の長さで交互に繰り返されて形成されたＳｉＣ材の柱
状体を挿入し、このＳｉＣ材の柱状体の長手方向に前記
荷電粒子ビームが伝播する伝播貫通孔を形成する前記伝
播貫通孔を形成する。Preferably, in the insertion through hole, a low-resistance columnar portion having a component ratio giving a low resistivity and a high-resistance columnar portion having a component ratio giving a high resistivity have a predetermined length in the longitudinal direction. A columnar body of a SiC material formed by being alternately repeated is inserted, and the propagation through hole forming a propagation through hole through which the charged particle beam propagates is formed in the longitudinal direction of the columnar body of the SiC material.
【００２０】また、本発明による静電レンズ は、荷電
粒子ビームを発散あるいは収束させるための静電レンズ
であって、絶縁性筒体の挿入貫通孔に高抵抗材柱状体と
低抵抗材柱状体とを互いに隙間なく交互に挿入し、前記
低抵抗材柱状体と前記高抵抗材柱状体とを前記絶縁性筒
体に一体化させた状態で前記低抵抗材柱状体および前記
高抵抗材柱状体に前記荷電粒子ビームが伝播する伝播貫
通孔を形成したことを特徴とする。Further, the electrostatic lens according to the present invention is an electrostatic lens for diverging or converging a charged particle beam, and has a high resistance material columnar body and a low resistance material columnar body in the insertion through hole of the insulating cylindrical body. And the high-resistance material columnar body are integrated with the insulating cylinder, and the low-resistance material columnar body and the high-resistance material columnar body are alternately inserted into each other without a gap. In addition, a propagation through hole through which the charged particle beam propagates is formed.
【００２１】[0021]
【作用】絶縁性筒体の挿入貫通孔に高抵抗材柱状体と低
抵抗材柱状体とを互いに隙間なく交互に挿入し、低抵抗
材柱状体と前記高抵抗材柱状体とを前記絶縁性筒体に一
体化させた状態で低抵抗材柱状体および高抵抗材柱状体
に伝播貫通孔を形成することにより、予め貫通孔の形成
された静電レンズを構成する各レンズを同軸合わせして
組み立てる必要がないので、組立工程において同軸度を
低下させることがなく高い同軸度を有する静電レンズを
提供することができる。The high-resistance material columnar body and the low-resistance material columnar body are alternately inserted into the insertion through hole of the insulating cylindrical body without a gap, and the low-resistance material columnar body and the high-resistance material columnar body are insulated from each other. By forming propagation through-holes in the low-resistance material columnar body and the high-resistance material columnar body in a state of being integrated with the cylindrical body, the respective lenses constituting the electrostatic lens having the through-holes formed in advance are coaxially aligned. Since it is not necessary to assemble, it is possible to provide an electrostatic lens having high coaxiality without lowering the coaxiality in the assembly process.
【００２２】[0022]
【実施例】以下に図面を参照して本発明の実施例につい
て説明する。図１は本発明の静電レンズの第１実施例を
示す。図１において、静電レンズ１は、セラミクスなど
の絶縁性筒体２に形成された挿入貫通孔３に、ＳｉＣな
どを含む高抵抗材柱状体４、６に金属材料からなる低抵
抗材柱状体５が挟まれて挿入され固定保持されている。
高抵抗材柱状体４、６と低抵抗材柱状体５の中心部に
は、電子ビームが伝播するための円筒状の伝播貫通孔７
が形成されている。伝播貫通孔７は、挿入貫通孔３に高
抵抗材柱状体４、６と低抵抗材柱状体５とが挿入し絶縁
性筒体２の固定保持した状態で、形成される。高抵抗材
柱状体４、６と低抵抗材柱状体５の絶縁性筒体２への挿
入固定は、焼きばめなどのかたいはめあいや接着などに
より行われ、伝播貫通孔７の加工時に軸ずれが生じなけ
ればよい。絶縁性筒体２の外側面からは高抵抗材柱状体
４、６と低抵抗材柱状体５の側面側に至る貫通孔８、
９、１０が形成されている。貫通孔８、９には高抵抗材
柱状体４、６をアース１１に接地するための電線１２が
配設されており、貫通孔１０には低抵抗材柱状体５に負
電圧を印可する電源１４へ接続された電線１３が配設さ
れている。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the electrostatic lens of the present invention. In FIG. 1, an electrostatic lens 1 includes a high resistance material columnar body 4 and 6 containing SiC or the like in an insertion through hole 3 formed in an insulating cylindrical body 2 such as ceramics, and a low resistance material columnar body made of a metal material. 5 is sandwiched and inserted, and is fixedly held.
In the central portions of the high resistance material pillars 4 and 6 and the low resistance material pillars 5, a cylindrical propagation through hole 7 for the electron beam to propagate.
Are formed. The propagation through hole 7 is formed in a state where the high resistance material columnar bodies 4 and 6 and the low resistance material columnar body 5 are inserted into the insertion through hole 3 and the insulating cylindrical body 2 is fixedly held. Insertion and fixation of the high-resistance material columnar bodies 4 and 6 and the low-resistance material columnar body 5 into the insulating cylindrical body 2 are performed by a hard fit such as shrink fitting or adhesion, and when the propagation through hole 7 is processed, an axis shift occurs. Should not occur. Through holes 8 extending from the outer surface of the insulating tubular body 2 to the side surfaces of the high-resistance material columnar bodies 4 and 6 and the low-resistance material columnar body 5,
9 and 10 are formed. An electric wire 12 for grounding the high resistance material pillars 4 and 6 to the earth 11 is disposed in the through holes 8 and 9, and a power source for applying a negative voltage to the low resistance material pillars 5 in the through hole 10. An electric wire 13 connected to 14 is provided.
【００２３】電子ビームの出射位置１５から出射した電
子ビームは伝播貫通孔７を経て、試料台の試料１６へ結
像されるようになっている。The electron beam emitted from the electron beam emitting position 15 is imaged on the sample 16 on the sample stage through the propagation through hole 7.
【００２４】なお、挿入貫通孔３は必ずしも円筒形状で
ある必要はなく従って高抵抗材柱状体４、６や低抵抗材
柱状体５の円筒柱状体である必要はなく、挿入貫通孔３
は多角柱形状や非対称の柱形状でもよく従って高抵抗材
柱状体４、６や低抵抗材柱状体５は、例えば図３に示す
ように、挿入貫通孔３の挿入され固定保持される柱状体
であればよい。なお、低抵抗材は、合金であってもＡ
ｌ、Ｔｉ等の純金属でもよく、またＴｉＢ２入りセラミ
ックス材でもよい。It should be noted that the insertion through-hole 3 does not necessarily have a cylindrical shape, and therefore does not have to be the cylindrical columnar body of the high-resistance material columnar bodies 4 and 6 or the low-resistance material columnar body 5, and the insertion through-hole 3
May have a polygonal columnar shape or an asymmetrical columnar shape. Therefore, the high-resistance material columnar bodies 4 and 6 and the low-resistance material columnar body 5 are, for example, as shown in FIG. If Even if the low resistance material is an alloy, A
Pure metals such as l and Ti may be used, or a TiB 2 -containing ceramic material may be used.
【００２５】次に、本実施例の静電レンズ１の作用効果
について説明する。比較のために、図９に従来の静電レ
ンズ１２０を示す。図９に示すように、高抵抗材柱状体
１２１には伝播貫通孔１２２が形成されており、伝播貫
通孔１２２の中間部には電気導電膜１２３がコーティン
グされており、電気導電膜１２３には電源１２４によっ
て電圧を印加されるようになっている。しかしながら、
従来の静電レンズ１２０においては、電気導電膜１２３
を伝播貫通孔１２２の奥深い内部にコーティングされる
ようになっているので、コーティングすること自身が容
易でなく、また所定位置に電気導電膜１２３を高精度に
形成することが容易でなかったのである。Next, the function and effect of the electrostatic lens 1 of this embodiment will be described. For comparison, a conventional electrostatic lens 120 is shown in FIG. As shown in FIG. 9, a propagation through hole 122 is formed in the high resistance material columnar body 121, an electric conductive film 123 is coated in the middle portion of the propagation through hole 122, and the electric conductive film 123 is formed. A voltage is applied by the power supply 124. However,
In the conventional electrostatic lens 120, the electrically conductive film 123
Since it is designed to be coated deep inside the propagation through hole 122, it is not easy to coat itself and it is not easy to form the electric conductive film 123 at a predetermined position with high precision. .
【００２６】これに対して、本実施例の静電レンズ１で
は、低抵抗材柱状体５は挿入貫通孔３へ挿入されて伝播
貫通孔７が形成されるので、伝播貫通孔７の奥深い内部
にはコーティングが不要であり、静電レンズ１は容易に
製造可能な構成を有する。On the other hand, in the electrostatic lens 1 of this embodiment, the low-resistance material columnar body 5 is inserted into the insertion through hole 3 to form the propagation through hole 7, so that the deep inside of the propagation through hole 7 is formed. Requires no coating, and the electrostatic lens 1 has a configuration that can be easily manufactured.
【００２７】次に、図２を参照して、図１に示した静電
レンズ１の製造方法について説明する。図２において、
セラミクス製の絶縁性筒体２に、長手方向に貫通する挿
入貫通孔３と内側面から外側面へ貫通する貫通孔８、
９、１０を形成しておく。次に、挿入貫通孔３に孔形状
に対応して成形された高抵抗材柱状体６、低抵抗材柱状
体５および高抵抗材柱状体４をこの順序で挿入貫通孔３
へ挿入し、焼きばめなどのかたいはめあいや接着などに
より絶縁性筒体２に固定保持する。Next, a method of manufacturing the electrostatic lens 1 shown in FIG. 1 will be described with reference to FIG. In FIG.
In the insulating cylinder body 2 made of ceramics, the insertion through hole 3 penetrating in the longitudinal direction and the through hole 8 penetrating from the inner side surface to the outer side surface,
9 and 10 are formed. Next, the high-resistance material columnar body 6, the low-resistance material columnar body 5, and the high-resistance material columnar body 4 formed in the insertion through-hole 3 corresponding to the hole shape are inserted in this order.
And is fixedly held to the insulating cylindrical body 2 by a hard fit such as a shrink fit or adhesion.
【００２８】高抵抗材柱状体６、低抵抗材柱状体５およ
び高抵抗材柱状体４は、長手方向に互いに隙間無く接触
するように押しつけられたおり、このために互いの接触
する底平面は互いに隙間無く接触できるような平面度、
例えば３μｍの平面度で加工されている。The high-resistance material columnar body 6, the low-resistance material columnar body 5, and the high-resistance material columnar body 4 are pressed in the longitudinal direction so as to be in contact with each other without a gap. Therefore, the bottom planes in contact with each other are Flatness so that they can contact each other without gaps,
For example, it is processed with a flatness of 3 μm.
【００２９】次に、高抵抗材柱状体４、６と低抵抗材柱
状体５とを絶縁性筒体２に固定保持した状態で、これら
の中心部に円筒状の伝播貫通孔７を形成する。Next, with the high-resistance material columnar bodies 4 and 6 and the low-resistance material columnar body 5 being fixedly held in the insulating cylindrical body 2, a cylindrical propagation through hole 7 is formed in the central portion thereof. .
【００３０】次に、このようにして製造された静電レン
ズの作用について説明する。金属筒体からなる低抵抗材
柱状体５に外部電源１４によって負電圧が印加すること
で、図７に示すように伝播貫通孔７内には低抵抗材柱状
体５を中心に負電位のピークが生じ両側の高抵抗材柱状
体４、６に向かって零電位に近づく電位分布が形成され
る。この結果、図６に示したものと同等の３個のレンズ
からなる静電レンズ１が形成され、伝播貫通孔７内を通
過する電子ビームの制御が可能になる。Next, the operation of the electrostatic lens thus manufactured will be described. By applying a negative voltage to the low-resistance material columnar body 5 made of a metal cylinder by the external power source 14, as shown in FIG. 7, a negative potential peak is centered on the low-resistance material columnar body 5 in the propagation through hole 7. Occurs, a potential distribution that approaches zero potential is formed toward the high-resistance material columnar bodies 4 and 6 on both sides. As a result, the electrostatic lens 1 composed of three lenses equivalent to those shown in FIG. 6 is formed, and the electron beam passing through the propagation through hole 7 can be controlled.
【００３１】本実施例の構成によれば、伝播貫通孔７
は、高抵抗材柱状体４、６と低抵抗材柱状体５とを絶縁
性筒体２に固定保持した状態で形成されているので、電
子レンズ１を構成する各レンズは高同軸性で互いに位置
合わせされたことと同等に配置されたことになる。According to the configuration of this embodiment, the propagation through hole 7
Is formed in a state where the high-resistance material columnar bodies 4 and 6 and the low-resistance material columnar body 5 are fixedly held in the insulating cylindrical body 2, so that the lenses forming the electron lens 1 are highly coaxial with each other. It means that they are arranged in the same way as they are aligned.
【００３２】また、この高同軸性は、高抵抗材柱状体
４、６と低抵抗材柱状体５とを絶縁性筒体２に固定保持
した状態で伝播貫通孔７を形成するだけで容易に実現で
き、煩雑の位置合わせを必要としない。従って、複雑な
加工が少なくなり、形状精度の向上および加工コストと
加工時間半減を図ることができ、また組み立て後に伝播
貫通孔７をあけるため中心軸上の同軸度や同心度に関し
ては約１μｍ以下の組み立て精度で完了することができ
る。The high coaxiality can be easily obtained by forming the propagation through hole 7 in a state where the high resistance material columnar bodies 4 and 6 and the low resistance material columnar body 5 are fixedly held in the insulating cylindrical body 2. It can be realized and does not require complicated alignment. Therefore, complicated processing is reduced, the shape accuracy can be improved, the processing cost and the processing time can be reduced by half, and the coaxiality or concentricity on the central axis is about 1 μm or less for forming the propagation through hole 7 after assembly. Can be completed with the assembly accuracy of.
【００３３】また、図８に示す従来の静電レンズ１１０
のように各電極１１１、１１２、１１３をホルダ１１４
にねじ止めして精度良く組み立てす必要がない。Further, the conventional electrostatic lens 110 shown in FIG.
As shown in FIG.
It is not necessary to screw it on and assemble it accurately.
【００３４】また、図８に示す従来の静電レンズ１１０
において、帯電防止するためには電極１１１、１１２、
１１３は互いに重なりあうような形状にし電子ビームか
らセラミックホルダ１１４の壁面を直接見えないように
する必要があり、また同時にレンズ収差減少させる必要
があり、電極１１１、１１２、１１３の形状が複雑にな
っていた。これに伴いセラミックホルダ１１４の形状も
複雑化し、静電レンズ１１０の全体形状が大型化してし
まい、製作が容易でなくコスト高になっていた。The conventional electrostatic lens 110 shown in FIG.
In order to prevent electrification, the electrodes 111, 112,
It is necessary to form 113 so as to overlap each other so that the wall surface of the ceramic holder 114 cannot be directly seen from the electron beam, and at the same time, it is necessary to reduce the lens aberration, and the shapes of the electrodes 111, 112, 113 become complicated. Was there. Along with this, the shape of the ceramic holder 114 also becomes complicated, and the overall shape of the electrostatic lens 110 becomes large, making it difficult to manufacture and increasing the cost.
【００３５】これに対し、本実施例では、伝播貫通孔７
は、高抵抗材柱状体４、６と低抵抗材柱状体５の各々を
貫通して形成されており、伝播貫通孔７を通る電子ビー
ムからは絶縁性筒体２の壁面を見えないので、電子ビー
ムが絶縁性筒体２の壁面に帯電を誘起することはなく帯
電は防止される。また、高抵抗材柱状体４、６と低抵抗
材柱状体５が柱状体という単純な形状にもかかわらず、
帯電防止できるので、高抵抗材柱状体４、６と低抵抗材
柱状体５の各々の長手方向の長さを適当に選択すること
によりレンズ収差を減少させることができる。これらの
結果、絶縁性筒体２の形状も複雑にする必要がなく、静
電レンズ１の全体形状を小型化でき、製作が容易で低コ
スト化できる。例えば、図８に示す静電レンズ１１０の
外径が約２０ｍｍであるのに対し、本実施例では外形を
１０ｍｍ以下にすることができる。On the other hand, in this embodiment, the propagation through hole 7
Is formed by penetrating each of the high resistance material columnar bodies 4 and 6 and the low resistance material columnar body 5, and since the electron beam passing through the propagation through hole 7 cannot see the wall surface of the insulating cylindrical body 2. The electron beam does not induce charging on the wall surface of the insulating cylindrical body 2, and charging is prevented. In addition, although the high-resistance material columnar bodies 4 and 6 and the low-resistance material columnar body 5 are simple columns,
Since the charging can be prevented, the lens aberration can be reduced by appropriately selecting the longitudinal lengths of the high resistance material columnar bodies 4 and 6 and the low resistance material columnar body 5. As a result, the shape of the insulating cylindrical body 2 does not need to be complicated, the overall shape of the electrostatic lens 1 can be downsized, and the manufacturing is easy and the cost can be reduced. For example, the outer diameter of the electrostatic lens 110 shown in FIG. 8 is about 20 mm, while the outer diameter can be set to 10 mm or less in this embodiment.
【００３６】なお、本実施例において、静電レンズは高
抵抗材柱状体４、６と低抵抗材柱状体５の３個の柱状体
で構成されている例を示したが、３個に限らず、高抵抗
材柱状体と低抵抗材柱状体とが交互に配設されたもので
あれば、４個以上でもよい。これにより電子銃などのガ
ンレンズ部と対物レンズ部など複数のレンズを一体型に
組み込むこともできる。In this embodiment, the electrostatic lens is composed of the three columns of the high resistance material columnar bodies 4 and 6 and the low resistance material columnar body 5, but the electrostatic lens is not limited to three. Alternatively, four or more high-resistance material columnar bodies and low-resistance material columnar bodies may be arranged as long as they are alternately arranged. As a result, a plurality of lenses such as a gun lens unit such as an electron gun and an objective lens unit can be integrated.
【００３７】また、低抵抗材柱状体５は金属材料からな
るとしたが、低抵抗率の成分比率を有するＳｉＣ材から
なり、高抵抗材柱状体４、６を高抵抗率の成分比率を有
するＳｉＣ材からなるようにしてもよい。低抵抗率の成
分比率を有するＳｉＣ材としては、セラミックス材中に
ＳｉＣを約５０％含み、約１０-6Ωｃｍの抵抗を有する
ＳｉＣ材を用いることができる。高抵抗率の成分比率を
有するＳｉＣ材としては、セラミックス材中にＳｉＣを
約１０％含み、約１０3 〜１０5 Ωｃｍの抵抗を有する
ＳｉＣ材を用いることができる。Although the low-resistance material columnar body 5 is made of a metal material, it is made of a SiC material having a low resistivity component ratio, and the high-resistance material columnar bodies 4 and 6 are made of SiC having a high resistivity component ratio. It may be made of wood. As a SiC material having a low resistivity component ratio, a SiC material containing about 50% SiC in a ceramic material and having a resistance of about 10 −6 Ωcm can be used. As the SiC material having a high resistivity component ratio, a SiC material containing about 10% SiC in a ceramic material and having a resistance of about 10 3 to 10 5 Ωcm can be used.
【００３８】また、上述の実施例では、互いに別体とし
て形成された高抵抗材柱状体と低抵抗材柱状体とを交互
に挿入貫通孔３へ挿入した場合を説明した。しかしなが
ら、御発明は、これに限らず、高抵抗材柱状体と低抵抗
材柱状体とを以下のように一体で形成した場合でもよ
い。すなわち、低抵抗率を与える成分比率を有する低抵
抗柱状部分と高抵抗率を与える成分比率を有する高抵抗
柱状部分とが長手方向に所定の長さで交互に繰り返され
て形成されたＳｉＣ材の柱状体を製造し、この柱状体を
挿入貫通孔３に挿入し固定保持し、このＳｉＣ材の柱状
体の長手方向に伝播貫通孔７を形成してもよい。Further, in the above-mentioned embodiment, the case where the high-resistance material columnar body and the low-resistance material columnar body formed separately from each other are alternately inserted into the insertion through hole 3 has been described. However, the present invention is not limited to this, and the high resistance material columnar body and the low resistance material columnar body may be integrally formed as described below. That is, a SiC material formed by alternately repeating a low-resistance columnar portion having a component ratio giving a low resistivity and a high-resistance columnar portion having a component ratio giving a high resistivity at a predetermined length in the longitudinal direction. It is also possible to manufacture a columnar body, insert the columnar body into the insertion through hole 3 and fix and hold the columnar body, and form the propagation through hole 7 in the longitudinal direction of the columnar body of the SiC material.
【００３９】次に、本発明の他の実施例として、図４お
よび図５を参照して、ビームスキャナーや非点補正器あ
るいは偏光器等に利用する多極電極について説明する。
図４は、ビームスキャナー２０を示し、ビームスキャナ
ー２０はＳｉＣなどを含む高抵抗材柱状体２１を有す
る。高抵抗材柱状体２１には、長手方向に貫通し半径方
向に８方向に分岐した８個の分岐孔２２が形成されてい
る。また、高抵抗材柱状体２１の長手方向中間部には各
々の分岐孔２２の間に、半径方向に８方向に広がる８個
の電極端子孔２３が形成されている。Next, as another embodiment of the present invention, a multipolar electrode used for a beam scanner, an astigmatism corrector, a polarizer or the like will be described with reference to FIGS.
FIG. 4 shows the beam scanner 20, which has a high-resistance material columnar body 21 containing SiC or the like. Eight branch holes 22 penetrating in the longitudinal direction and branching in eight directions in the radial direction are formed in the high-resistance material columnar body 21. In addition, eight electrode terminal holes 23 are formed in the longitudinal middle portion of the high-resistance material columnar body 21 between the respective branch holes 22 so as to spread in eight radial directions.
【００４０】図５に示すように、各々の電極端子孔２３
には対応する電源２４によって任意の電圧を任意のタイ
ミングで印加できるようになっている。各々の電極端子
孔２３に電圧を印加するタイミングを組み合わせ、例え
ばビームスキャン用の電圧を印加することにより、図４
で矢印で示すように、電子ビームを試料台２５上にスキ
ャンすることができる。As shown in FIG. 5, each electrode terminal hole 23
Any voltage can be applied at any timing by the corresponding power supply 24. By combining the timings of applying the voltages to the respective electrode terminal holes 23 and applying the voltage for beam scanning, for example, as shown in FIG.
The electron beam can be scanned onto the sample stage 25 as indicated by the arrow.
【００４１】本実施例によれば、複数の分岐孔２２と複
数の電極端子孔２３を高抵抗材柱状体２１に形成したの
で、複数の分岐孔や複数の電極端子孔を別個個別に製造
して筒体に組み込むことと異なり互いに煩雑な位置合わ
せをする必要がなく、ＮＣ加工機械等を用いて、高抵抗
材柱状体２１の所定位置に高位置決めで複数の分岐孔２
２および電極端子孔２３を一体的に形成することができ
る。According to this embodiment, since the plurality of branch holes 22 and the plurality of electrode terminal holes 23 are formed in the high-resistance material columnar body 21, the plurality of branch holes and the plurality of electrode terminal holes are individually manufactured. It is not necessary to perform complicated alignment with each other, unlike the case where the high-resistance material columnar body 21 is highly positioned at a predetermined position by using an NC processing machine or the like.
2 and the electrode terminal hole 23 can be integrally formed.
【００４２】また、本実施例のビームスキャナー２０と
複数レンズとを組み合わせて、ビーム検査装置を一体の
システムとして構成することも可能であり、一体型とし
て構成できるので、各レンズおよびビームスキャナー２
０の電極間のアライメント精度も向上させることができ
る。Also, the beam scanner 20 of this embodiment and a plurality of lenses can be combined to form a beam inspection apparatus as an integrated system, and since it can be configured as an integrated type, each lens and beam scanner 2 can be configured.
The alignment accuracy between the zero electrodes can also be improved.
【００４３】なお、上述の説明において、荷電粒子ビー
ムとして電子ビームを例にして説明したが、本発明は電
子ビームの代わりにイオンビーム等の他の荷電粒子ビー
ムでも適用できる。In the above description, an electron beam was used as an example of the charged particle beam, but the present invention can be applied to other charged particle beams such as an ion beam instead of the electron beam.
【００４４】[0044]
【発明の効果】以上説明したように、本発明の構成によ
れば、高抵抗材柱状体と低抵抗材柱状体とを交互に絶縁
性筒体挿入し固定保持した状態で伝播貫通孔を形成する
だけで、煩雑の位置合わせを必要とせずに静電レンズを
容易に製造できる。この結果、複雑な加工が少なくな
り、形状精度の向上および加工コストと加工時間の短縮
を図ることができ、また組み立て後に伝播貫通孔をあけ
るため中心軸上の同軸度や同心度に関して高精度の組み
立て精度を実現することができる。As described above, according to the structure of the present invention, the propagation through hole is formed in a state where the high resistance material columnar body and the low resistance material columnar body are alternately inserted and fixedly held in the insulating cylinder body. Simply, the electrostatic lens can be easily manufactured without requiring complicated alignment. As a result, complicated processing is reduced, shape accuracy can be improved, processing cost and processing time can be shortened, and since the transmission through hole is opened after assembly, high accuracy in terms of coaxiality and concentricity on the central axis is achieved. Assembling accuracy can be realized.
【００４５】また、高抵抗材柱状体と低抵抗材柱状体と
を一体化した後、伝播貫通孔を形成するので、高抵抗材
柱状体によるレンズと低抵抗材柱状体によるレンズ間の
同軸度、同心度を、高精度例えば約１μｍ以下にするこ
とができ、この結果、低収差の静電レンズを得ることが
できる。Further, since the high resistance material columnar body and the low resistance material columnar body are integrated and the propagation through hole is formed, the concentricity between the lens made of the high resistance material columnar body and the lens made of the low resistance material columnar body is formed. , The concentricity can be made highly accurate, for example, about 1 μm or less, and as a result, an electrostatic lens with low aberration can be obtained.
【００４６】また、従来の静電レンズのように複数の金
属電極をセラミックホルダにより機械的に組み立てる必
要がないので、レンズ径および全体の形状の小形化と構
造の単純化を図ることができる。Further, unlike the conventional electrostatic lens, it is not necessary to mechanically assemble a plurality of metal electrodes with a ceramic holder, so that the lens diameter and overall shape can be reduced and the structure can be simplified.
【図１】本発明による静電レンズの一実施例を示す側面
図。FIG. 1 is a side view showing an embodiment of an electrostatic lens according to the present invention.
【図２】本発明による静電レンズの組み立て順序を示す
工程図。FIG. 2 is a process diagram showing an assembly sequence of an electrostatic lens according to the present invention.
【図３】本発明による静電レンズを角筒体を用いて構成
した例を示す斜視図。FIG. 3 is a perspective view showing an example in which an electrostatic lens according to the present invention is configured by using a rectangular tube body.
【図４】本発明によるビームスキャナーを示す斜視図。FIG. 4 is a perspective view showing a beam scanner according to the present invention.
【図５】図４におけるＡ−Ａからみた断面図。5 is a cross-sectional view seen from AA in FIG.
【図６】従来の静電レンズを示す概略断面図。FIG. 6 is a schematic sectional view showing a conventional electrostatic lens.
【図７】図６に示す静電レンズの中心軸上の電位分布を
示す図。7 is a diagram showing a potential distribution on a central axis of the electrostatic lens shown in FIG.
【図８】従来の静電レンズを示す概略断面図。FIG. 8 is a schematic sectional view showing a conventional electrostatic lens.
【図９】従来の他の静電レンズを示す概略断面図。FIG. 9 is a schematic sectional view showing another conventional electrostatic lens.
【図１０】静電レンズの同軸度とビーム径ぼけ率の関係
を示す図。FIG. 10 is a diagram showing a relationship between coaxiality of an electrostatic lens and a beam diameter blur ratio.
１ 静電レンズ ２ 絶縁性筒体 ３ 挿入貫通孔 ４、６ 高抵抗材柱状体 ５ 低抵抗材柱状体 ７ 伝播貫通孔 ８、９ １０ 貫通孔 １２ 電源 １５ 電子ビーム １６ 試料台 ２０ ビームスキャナー 1 Electrostatic Lens 2 Insulating Cylindrical Body 3 Insertion Through Hole 4, 6 High Resistance Material Columnar Body 5 Low Resistance Material Columnar Body 7 Propagation Through Hole 8, 9 10 Through Hole 12 Power Supply 15 Electron Beam 16 Sample Stand 20 Beam Scanner
Claims (4)
ための静電レンズの製造方法において、 絶縁性筒体の挿入貫通孔に高抵抗材柱状体と低抵抗材柱
状体とを互いに隙間なく交互に挿入し、前記低抵抗材柱
状体と前記高抵抗材柱状体とを前記絶縁性筒体に一体化
させた状態で前記低抵抗材柱状体および前記高抵抗材柱
状体に前記荷電粒子ビームが伝播する伝播貫通孔を形成
することを特徴とする静電レンズの製造方法。1. A method of manufacturing an electrostatic lens for diverging or converging a charged particle beam, wherein a high-resistance material columnar body and a low-resistance material columnar body are alternately inserted into an insertion through hole of an insulating cylinder without a gap. The charged particle beam is propagated to the low resistance material columnar body and the high resistance material columnar body in a state where the low resistance material columnar body and the high resistance material columnar body are integrated with the insulating cylinder body. A method for manufacturing an electrostatic lens, characterized in that a propagation through hole is formed.
記高抵抗材柱状体はＳｉＣ材からなることを特徴とする
請求項１に記載の静電レンズの製造方法。2. The method of manufacturing an electrostatic lens according to claim 1, wherein the low-resistance material columnar body is made of a metal material, and the high-resistance material columnar body is made of a SiC material.
を有するＳｉＣ材からなり、前記高抵抗材柱状体は高抵
抗率の成分比率を有するＳｉＣ材からなることを特徴と
する請求項１に記載の静電レンズの製造方法。3. The low-resistance material columnar body is made of a SiC material having a low resistivity component ratio, and the high-resistance material columnar body is made of a SiC material having a high resistivity component ratio. Item 1. A method for manufacturing an electrostatic lens according to item 1.
ための静電レンズであって、絶縁性筒体の挿入貫通孔に
高抵抗材柱状体と低抵抗材柱状体とを互いに隙間なく交
互に挿入し、前記低抵抗材柱状体と前記高抵抗材柱状体
とを前記絶縁性筒体に一体化させた状態で前記低抵抗材
柱状体および前記高抵抗材柱状体に前記荷電粒子ビーム
が伝播する伝播貫通孔を形成したことを特徴とする静電
レンズ。4. An electrostatic lens for diverging or converging a charged particle beam, wherein a high resistance material columnar body and a low resistance material columnar body are alternately inserted into an insertion through hole of an insulating cylinder without a gap. Then, the charged particle beam propagates to the low resistance material columnar body and the high resistance material columnar body in a state where the low resistance material columnar body and the high resistance material columnar body are integrated with the insulating cylinder. An electrostatic lens characterized in that a propagation through hole is formed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13806095A JP3335798B2 (en) | 1995-06-05 | 1995-06-05 | Electrostatic lens and method of manufacturing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13806095A JP3335798B2 (en) | 1995-06-05 | 1995-06-05 | Electrostatic lens and method of manufacturing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08329872A true JPH08329872A (en) | 1996-12-13 |
| JP3335798B2 JP3335798B2 (en) | 2002-10-21 |
Family
ID=15213046
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13806095A Expired - Fee Related JP3335798B2 (en) | 1995-06-05 | 1995-06-05 | Electrostatic lens and method of manufacturing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3335798B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100304978B1 (en) * | 1998-07-06 | 2001-10-19 | 김영환 | Subminiature electrostatic lens and method for manufacturing the same |
| JP2005191204A (en) * | 2003-12-25 | 2005-07-14 | Kyocera Corp | Optical element assembling body, assembling method, and electron beam apparatus using the same |
| WO2005122208A3 (en) * | 2004-06-11 | 2006-04-13 | Lbleiterprueftechnik Mbh Ict I | Charged particle beam device with retarding field analyzer |
| JP2010034075A (en) * | 2009-11-09 | 2010-02-12 | Kyocera Corp | Method of assembling optical element assembly |
-
1995
- 1995-06-05 JP JP13806095A patent/JP3335798B2/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100304978B1 (en) * | 1998-07-06 | 2001-10-19 | 김영환 | Subminiature electrostatic lens and method for manufacturing the same |
| JP2005191204A (en) * | 2003-12-25 | 2005-07-14 | Kyocera Corp | Optical element assembling body, assembling method, and electron beam apparatus using the same |
| WO2005122208A3 (en) * | 2004-06-11 | 2006-04-13 | Lbleiterprueftechnik Mbh Ict I | Charged particle beam device with retarding field analyzer |
| US8203119B2 (en) | 2004-06-11 | 2012-06-19 | Ict Integrated Circuit Testing Gesellschaft Fur Halbleiterpruftechnik Mbh | Charged particle beam device with retarding field analyzer |
| JP2010034075A (en) * | 2009-11-09 | 2010-02-12 | Kyocera Corp | Method of assembling optical element assembly |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3335798B2 (en) | 2002-10-21 |
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