JPS6053021A - Electron beam drawing device - Google Patents

Abstract

PURPOSE:To reduce unnecessary irradiation to a sample to be drawn with a pattern to be generated according to multiple reflections at an electron beam drawing device by a method wherein the surface of the mirror body of the drawing device is covered with a material composed of the element or the compound of a low atomic number (the atomic number is 13 or less). CONSTITUTION:An electron beam 1 radiated from an electron gun is converged to be deflected by a final stage lens 2, and made to enter in a sample 3 to be drawn with a pattern. The reflected electron beam thereof is detected by detectors 9, and used for positional detection of a mark on the sample to be drawn with the pattern. At this time, the part facing to the sample to be drawn with the pattern of the final stage lens 2 is covered with an acrylic resin plate 6 of 0.5mm. thickness adhered with an aluminum film 7 of 100nm thickness, and the aluminum film 7 thereof is earthed electrically by fixing to the final stage lens 2 according to conductive screws 8. Moreover, the holders of the reflected electron beam detectors are also manufactured of acrylic resin 9, the surfaces thereof are covered with aluminum films 10 of 0.1mum thickness, and earthed electrically by fixing mechanically to the final stage lens 2. Accordingly, parasitic irradiation to the sample to be drawn with the pattern according to the electron beam reflected by two times can be reduced to 1/2 or less.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は、′１（電子線描画装置の改良に係υ、的に装
置内での′電子の反射に伴う不必要な電子線照射を減少
する構造に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to the improvement of electron beam lithography equipment, specifically, to reduce unnecessary electron beam irradiation due to reflection of electrons within the equipment. It is related to the structure of

〔発明の背景〕[Background of the invention]

従来電子付描画装置の被描画試料付近の構造を第１図に
示す。電子銃より放射でれた電子＆、１は最終段のレン
ズ２で集束・偏向されて被描画試料３ｖ？−入射する。FIG. 1 shows the structure of a conventional electron drawing apparatus near a sample to be drawn. The electrons &,1 emitted from the electron gun are focused and deflected by the lens 2 in the final stage to the sample to be drawn 3v? -Inject.

この時入射電子の一部は反射して再びレンズ２の方向に
戻っていく。この反射電子は検出器４で検出されて、被
描画試料上のマークの位置検出に用いらねる。しかし、
レンズ２および検出器４のホルダは非磁性材料である燐
青銅で作られることが多く、反射電子のさらに一部５が
再び反射して被描画試料に照射されるという欠点があっ
た。At this time, some of the incident electrons are reflected and return toward the lens 2 again. These reflected electrons are detected by the detector 4 and used to detect the position of the mark on the sample to be drawn. but,
The lens 2 and the holder of the detector 4 are often made of phosphor bronze, which is a non-magnetic material, which has the disadvantage that a further part 5 of the backscattered electrons is reflected again and irradiated onto the sample to be drawn.

〔発明の目的〕[Purpose of the invention]

本発明の目的は、上述した電子線が描画装置内で多重反
射することによって生じる被描画試料への不要が照射を
低減し得る電子線描画装置を提供するものである。An object of the present invention is to provide an electron beam lithography apparatus that can reduce unnecessary irradiation of a sample to be lithographically generated due to multiple reflections of the above-mentioned electron beam within the lithography apparatus.

〔発明の概要〕[Summary of the invention]

上記の目的を達成するために、本発明の電子線描画装置
では、被描画試料に照射された電子線の反射電子線が当
る描画装置の鏡体表面を低原子番号（異本的には原子番
号１３以下）の元素又は化合物で構成された材料で覆う
ことで、鏡体表面からの反射電子を減少する如く構成し
たものである。In order to achieve the above object, in the electron beam lithography apparatus of the present invention, the mirror surface of the lithography apparatus, which is hit by the reflected electron beam of the electron beam irradiated onto the sample to be lithography, has a low atomic number (alternatively, an atomic number By covering the mirror with a material composed of an element or compound (13 or less), reflected electrons from the surface of the mirror are reduced.

さらに、この低原子番号の利料の表面を電気伝尋度の商
い材料で覆い電気的に接地することで、入射した電子に
よるチギージアツプの悪影響を防止するものである。Furthermore, by covering the surface of this low atomic number material with a material having a high electrical conductivity and electrically grounding it, the adverse effects of oxidation jump caused by incident electrons can be prevented.

〔発明の実施例〕[Embodiments of the invention]

以下本発明を実施例を用いて詳細に説明する。 The present invention will be explained in detail below using examples.

第２図は、本発明の一実施例を示す図である。最終段の
レンズ２の被描画試料に面した部分を、膜厚１１００ｎ
のアルミニウム７で被着式れたハフさ０．５ｖｒｌのア
クリル桐脂板６で覆う構造とした。このアルミニウム７
はアクリル樹ｊ財板６の全表面を覆っているため、最終
段レンズ２に導電性のねじ８により固定することで電気
的に接地することが可能である。７上お、反射電子の検
出器のホルダをアクリル樹脂９で製作し、その表面を膜
厚０．１μｍのアルミニウム１０で覆った。この（炙出
器のホルダも最終段レンズ２に機械的に固定されて電気
的接地を行っている。従来の構造では、２回反射電子に
よる被描画試料への照射が１次の照射鼠の１０％であっ
たものが、この改良の結果３％以下となり、１／３以下
に低減すること力よできた。また、その他の電子光学的
特性は従来構造との差はなかった。FIG. 2 is a diagram showing an embodiment of the present invention. The part of the final stage lens 2 facing the sample to be drawn has a film thickness of 1100 nm.
It has a structure in which it is covered with an acrylic paulownia plate 6 having a huff of 0.5 vrl and coated with aluminum 7. This aluminum 7
covers the entire surface of the acrylic wood board 6, so it can be electrically grounded by fixing it to the final stage lens 2 with conductive screws 8. 7. Also, a holder for a backscattered electron detector was made of acrylic resin 9, and its surface was covered with aluminum 10 having a thickness of 0.1 μm. The holder of this explorator is also mechanically fixed to the final stage lens 2 and electrically grounded. In the conventional structure, the irradiation of the specimen by the twice reflected electrons is the first irradiation of the irradiation device. As a result of this improvement, it was 10%, but as a result of this improvement, it was reduced to 3% or less, which was successfully reduced to 1/3 or less.Furthermore, there was no difference in other electro-optical properties from the conventional structure.

第３図は、本発明の他の実施例を示す図である。FIG. 3 is a diagram showing another embodiment of the present invention.

本実施例では、低原子番号の材料として炭素（原子番号
６）を用いた。さらに具体的には、ブラフアイトラ用い
て厚さ２胡の板１１と反射電子の検出器１２を製作した
。本実施例に用いたグラファイトは、比抵抗が数オーム
・センチメートルであるため、その全表面を高電気伝導
材料で覆う必要はない。グラファイトが被描画試料に面
している領域に、膜厚２０ｎｍのアルミニウム１３を被
着することで、表面を接地電位に抑えること力１」ヒで
あった。本実施例による改良の効果は、前述の実施例と
ほぼ同一であった。In this example, carbon (atomic number 6) was used as the low atomic number material. More specifically, a plate 11 with a thickness of 2 mm and a backscattered electron detector 12 were manufactured using Bluff Eye Trap. Since the graphite used in this example has a specific resistance of several ohms/centimeters, it is not necessary to cover its entire surface with a highly electrically conductive material. By depositing aluminum 13 with a thickness of 20 nm on the region where the graphite faces the sample to be drawn, it was possible to suppress the surface to the ground potential. The improvement effect of this example was almost the same as that of the previous example.

第４図は、本発明のさらに他の実施例を示す図である。FIG. 4 is a diagram showing still another embodiment of the present invention.

本実施例では、比較的原子番号は太きいが高電気伝導度
を有するアルミニウム（原子番号１３）を用いて厚さ１
咽の板１５と反射電子の検出器１４を製作した。この場
合には単一材料で反射防市とチャージアップ防止の効果
を有する。この時の２回の反射電子による被照射試料へ
の照射は、従来構造の約１７２であった。In this example, aluminum (atomic number 13), which has a relatively large atomic number but high electrical conductivity, is used to
A throat plate 15 and a backscattered electron detector 14 were manufactured. In this case, a single material has the effect of preventing reflection and charge-up. The irradiation of the irradiated sample by the two reflected electrons at this time was about 172 in the conventional structure.

〔発明の効果〕〔Effect of the invention〕

以上説明したごとく、本発明によれば、被描画試料から
の反射電子を低原子材料で作られた核いにより吸収し、
またその表面電位は接地電位に保たれているため、電子
光学特性に悪影響を与えることなく、２回反射電子によ
る被描画試料への寄生照射を１７２以下に低減すること
ができた。As explained above, according to the present invention, reflected electrons from a sample to be drawn are absorbed by a nucleus made of a low-atom material,
Furthermore, since its surface potential was maintained at ground potential, parasitic irradiation of the sample to be drawn due to twice reflected electrons could be reduced to 172 or less without adversely affecting the electron optical characteristics.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は、従来の電子線描画装置の被描画試料付近の構
造を示す断面図、第２図は、本発明の一実施例になる電
子線描画装置の被描画試料付近の構造を示す断面図、第
３図は、本発明の他の実施例を示す断面図、第４図は、
本発明のきらに他の実施例を示す断面図である。FIG. 1 is a sectional view showing the structure near the sample to be drawn in a conventional electron beam lithography system, and FIG. 2 is a cross sectional view showing the structure near the sample to be drawn in the electron beam lithography system according to an embodiment of the present invention. FIG. 3 is a sectional view showing another embodiment of the present invention, and FIG. 4 is a sectional view showing another embodiment of the present invention.
FIG. 7 is a sectional view showing another embodiment of the present invention.

Claims (1)

【特許請求の範囲】[Claims] １、電子線描画装置において、被描画試料に照射された
′電子線の反射電子が当る鏡体表面が、原子番号が１３
以下の元素または原子番号１３以下の元素を主構成元素
とする材料により構成された第１の材料で覆われ、さら
に該第１の材料が電気伝導度の高い第２の利料により覆
われ、該第２の材料は電気的に接地でれてなることを特
徴とする電子線描画装置。1. In an electron beam lithography system, the surface of the mirror that is hit by the reflected electrons of the electron beam irradiated onto the sample to be lithographic has an atomic number of 13.
Covered with a first material made of a material whose main constituent element is the following element or an element with an atomic number of 13 or less, and the first material is further covered with a second material having high electrical conductivity, An electron beam lithography apparatus characterized in that the second material is electrically grounded.