JP3531107B2 - Conductive ceramic deflection electrode - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive ceramic deflection electrode, and more particularly to an electrode material for preventing deterioration of a deflection electrode which constitutes an electrostatic deflection type sub-deflector of an electron beam exposure apparatus. The present invention relates to a conductive ceramic deflection electrode having a characteristic of a metallized material.

[0002]

2. Description of the Related Art In recent years, DRAM (dynamics random access memory) has been highly integrated year by year.
1Gbit DRAM is expected to become widespread in 2001. Such 1Gbit or 4Gbit DRAM
When manufacturing ultra high integration semiconductor devices such as
It is considered that an electron beam exposure technique, which is drawing attention as a lithography technique of m or less, is indispensable.

To date, as the wiring size has become smaller, a mercury lamp has been used as a light source for lithography.
From the line (= 435.8 nm) and i line (= 365 nm),
The wavelength is shifting to a KrF excimer laser (= 248 nm) and an ArF excimer laser (= 193 nm = 0.193 μm).

However, even with these light sources, 0.1
Since exposure of a pattern of μm or less is impossible, an electron beam exposure method using an electron beam having a shorter wavelength as a light source has been attracting attention.

Here, a schematic structure of the electron beam exposure apparatus will be described with reference to FIG. See FIG. 4. FIG. 4 is a conceptual configuration diagram of an example of the electron beam exposure apparatus. The thermoelectrons generated from the LaB ₆ electron gun 31 composed of the LaB ₆ chip are taken out as an electron beam 45, and various filters, masks and deflectors are used. Change the position, shape, etc. of the electron beam 45 with a container,
Drawing is performed on an electron beam resist (not shown) provided on a wafer 43 such as a Si wafer.

In this case, the position of the electron beam 45 is used by combining two kinds of deflection methods, that is, a deflection by a magnetic field and a deflection by an electric field, and the main deflector 41 using a magnetic field is a main deflection that performs a deflection in millimeter units. The sub-deflector 40 using an electric field is used for writing in the sub-deflection area for deflection within 100 μm.

The conventional electron beam exposure apparatus has the problems of low throughput and short life. Of these, the biggest reason for the low throughput is that it is difficult to perform pattern exposure in a batch like optical lithography.
That is, the spot diameter of the electron beam is narrowed down, and basically a drawing exposure method is adopted to scan all fine patterns, so that a long time is required for all drawing exposure.

Therefore, in order to move the electron beam to the spot position accurately and quickly, it is required to improve the characteristics of the sub-deflector of the electrostatic deflection system, and accordingly, the deflection electrodes constituting the sub-deflector are required. Improvement of characteristics is required.

With respect to the electrode material of the deflection electrode which constitutes such a sub-deflector, the electric resistance value at room temperature is 10 ^-1 Ω · c.
It is required to be around m. That is, it is basically important for the electrode material to have excellent conductivity, but since the sub-deflector applies an electric field in a magnetic field, a deflector that uses a low resistance element similar to a metal in a magnetic field is used. This is because when used as an electrode, there is a problem that an eddy current is generated around the electrode. In order to suppress the generation of this eddy current,
A resistance value of around 10 ⁻¹ Ω · cm is required.

Altic (Al ₂ O ₃ —TiC) type ceramics have been used as an electrode material satisfying such conditions, and a voltage is applied to a deflection electrode using this altic type ceramics. When forming the metallization layer for connecting the lead wire for
An Ag-Cu-Ti-based brazing material used as a metallizing method for carbide ceramics is applied.

This deflection electrode is used in a vacuum, and when drawing an electron beam resist provided on a wafer,
The resist resin that constitutes the electron beam resist scatters, and with time, resist scatters on the inner surface of the deflection electrode adhere, and since this resist is an insulator, these resist deposits cause charge-up. .

Therefore, in order to remove such undesired resist deposits, it is necessary to regularly ash the deflecting electrodes using oxygen plasma to clean the surface of the deflecting electrodes.

However, there is a problem that the deflection electrode using such AlTiC ceramics has a short life. That is, since TiC is contained in the AlTiC-based ceramics that constitutes the deflection electrode, TiC is oxidized in the cleaning process using oxygen plasma and Ti
This is because a Ti oxide such as O ₂ is formed, which changes the resistance value of the deflection electrode, and as a result, the desired deflection value cannot be obtained at the set voltage.

In order to solve such a problem, a deflection electrode in which the entire surface of Altic ceramics is coated with metal is also used. When such an improved deflection electrode is used, surface oxidation is not observed, but when oxygen plasma irradiation is performed for a long time, there is a problem that the metal film coated on the surface is sputtered and the deflection electrode deteriorates. .

Therefore, in order to solve the drawbacks of the deflecting electrode using such Altic ceramics, the applicant of the present invention has found that the ruthenium oxide (Ru oxide) composed of only an oxide is used.
O ₂ ) -based ceramic electrodes have been proposed.

[0016]

However, there is a problem in constructing a deflection electrode using such a ruthenium oxide-based ceramics. That is, in order to use the ruthenium oxide ceramics as a deflection electrode, it is necessary to form a metallization layer for connecting a lead wire on the outer surface of the deflection electrode having a curved shape. It is necessary that the adhesiveness is excellent and the surface is also excellent in solder wettability.

However, the Mo-Mn method and the Ag-Cu-Ti brazing filler metal cannot be directly applied to the ruthenium oxide ceramics which are not the alumina ceramics or the carbide ceramics, and the deflection having the curved shape is not possible. It was difficult to form a metallized layer on the electrode with high dimensional accuracy.

That is, since the Mo-Mn method is essentially a thick film process, a step of baking at a high temperature is adopted, so that the unevenness of the surface becomes large and it becomes difficult to form a uniform metallized layer. In addition, there is a problem that the adhesion deteriorates due to the reaction, and there is a problem that the solder wettability is not good. It On the other hand, Ag-Cu
The —Ti-based brazing material also requires high-temperature treatment at 800 to 900 ° C., which also has the same problem as the Mo—Mn method.

As described above, if the metallized layer cannot be formed with high dimensional accuracy, there is a problem that the clearance is reduced when assembling a sub-deflector having an eight-pole electrode structure by combining eight deflection electrodes.

Therefore, it is an object of the present invention to form a deflecting electrode with a conductive material which does not deteriorate and to form a metallized layer having a uniform thickness and excellent adhesion strength and solder wettability.

[0021]

FIG. 1 is a block diagram showing the principle of the present invention. Means for solving the problems in the present invention will be described with reference to FIG. In addition, FIG.
FIG. 1 is a schematic perspective view of an 8-pole electrode forming the sub-deflector, and FIG. 1B is a schematic perspective view of a main part of the deflecting electrode forming the 8-pole electrode. 1A and 1B, in order to achieve the above-mentioned object, the present invention provides at least a surface of a deflection electrode body 2 made of ceramics composed of a conductive oxide and a sintering aid. Ti, Cr, Zr, N
a conductive material containing at least one of i,
An adhesion metallization layer 3 in direct contact with the deflection electrode body 2,
Cu, Ni, Au, Pt, formed of a conductive material containing at least one of Ag, consisting connection metallization layer 4 which leads are connected, for connecting a lead wire
Is provided with a metallized layer having a multi-layered structure .

In this way, the deflection electrode body 2, especially the sub-deflection
As a conductive oxide forming the deflection electrode body 2 of the container 1,
RuO₂, ReO₂, IrO₂, SrVO₃, CaVO
₃, LaTiO₃, SrMoO₃, CaMoO₃, Sr
CrO₃, CaCrO₃, LaVO₃, GdVO₃, S
rMnO₃, CaMnO₃, NiCrO₃, BiCrO
₃, LaCrO₃, LnCrO₃, SrRuO₃, Sr
FeO₃, BaRuO ₃, LaMnO₃, LnMn
O₃, LaFeO₃, LnFeO₃, LaCoO₃, L
aRhO₃, LaNiO₃, PbRuO₃, Bi₂Ru
₂O₇, LaTaO ₃, BiRuO₃At least within
Use one to remove the adhered resist.
In the oxygen plasma irradiation step of
Is not changed, and therefore the electric resistance value changes.
Never.

Further, the metallization layer is made of Ti, Cr, Z.
Adhesion metallization layer 3 made of a conductive material containing at least one of r and Ni, particularly adhesion metallization layer 3 made of a physical vapor deposition layer, and Cu, Ni, A
By using the connection metallization layer 4 made of a conductive material containing at least one of u, Pt, and Ag, particularly the connection metallization layer 4 made of a plated film, a high temperature process is not required. , Good adhesion, Pb
A metallized layer having good wettability with -Sn solder and excellent in film thickness uniformity can be formed on a curved oxide ceramic.

Further, in order to increase the electric resistance to a proper value by using a sintering aid as the ceramic consisting of a conductive oxide and a sintering aid, for example, 10 ^-4 to 10 ⁴ Ω. c
In order to obtain m, it is desirable to use a glass mainly composed of borosilicate glass having a softening point of 400 ° C. or higher and containing no lead component.

If the softening point is less than 400 ° C., it will be difficult to withstand the thermal environment during use as a deflecting electrode, and if lead (Pb) is contained in the glass, it will be exposed in a high temperature environment. There is a problem that Pb is deposited on the surface and becomes conductive, and the resistance value of the deflection electrode body 2 decreases. However, there is no particular problem as long as the glass containing the Pb component is contained in a small amount.

Further, it is desirable that the coefficient of thermal expansion of the ceramic composed of the conductive oxide and the sintering aid is 10 ^-5 / ° C. or less so that the physical arrangement does not change in the use environment.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Now, with reference to FIG. 2, a manufacturing process of a deflection electrode according to a first embodiment of the present invention will be described. See FIG. 2 (a). First, RuO ₂ and borosilicate glass are mixed, for example, in a weight ratio of 2
The composite mixed at a ratio of 0:80 is ground and polished to form a plate-shaped RuO ₂ system deflection electrode body 11 having a curved cross section. Incidentally, the resistivity of the main body 11 of the RuO ₂ system deflection electrode in this case is 10 ⁻¹ Ω · c by mixing RuO ₂ having a resistivity of 10 ⁻⁴ Ω · cm with an insulating borosilicate glass.
It will be about m.

Next, referring to FIG. 2 (b), the resist pattern (not shown) is used as a mask and the thickness is, for example, 10 by a sputtering method.
After the Ti adhesion improving layer 12 having a thickness of 0 nm is formed, the Pt barrier layer 13 having a thickness of, for example, 200 nm is subsequently formed.

Next, referring to FIG. 2C, an Au plating layer 14 having a thickness of, for example, 2 μm is formed on the Pt barrier layer 13 by electroless plating, and then the resist pattern is removed to form a resist pattern. Lift off unnecessary deposits deposited on top.

Next, referring to FIG. 2D, a Pb-Sn solder 15 is formed on the Au plating layer 14, and a voltage is applied to the RuO ₂ system deflection electrode main body 11 using the Pb-Sn solder 15. The basic structure of the deflection electrode is completed by connecting the lead wire 16.
After that, an electrostatic deflection type sub-deflector can be obtained by arranging eight deflection electrodes formed in this way at equal intervals on the circumference to form an eight-pole electrode.

[0031]

[Table 1] In the deflection electrode according to the first embodiment of the present invention, the Ti adhesion improving layer 12 is provided before forming the Au plating layer 14 serving as the metallization layer. It is possible to form a metallized layer having a uniform film thickness distribution and excellent adhesion strength and solder wettability as compared with the case of using the —Mn method or the Ag—Cu—Ti based brazing material.

Incidentally, the film thickness distribution within 10 mm square was ˜5%, the adhesion strength was 3 kg / mm ² , and the solder wettability was 90%. Note that solder wettability (%)
Is the ratio of the surface area of the solder covering the surface to the surface area of the metallized layer.

Further, the RuO ₂ system deflection electrode body 11 is
Since it is composed of conductive oxide ceramics consisting only of uO ₂ and borosilicate glass, the conductive oxide ceramics are further oxidized even when exposed to oxygen plasma in the cleaning process accompanying the deposition of the resist scattered matter. Therefore, the electric resistance value of the RuO ₂ system deflection electrode body 11 does not change.

Further, since the sintering aid for the conductive oxide ceramics is borosilicate glass which does not contain Pb and has a softening point of 400 ° C. or higher as described above, it is thermally deformed to the temperature environment in the electron beam exposure process. Can withstand without.

Therefore, even when the RuO ₂ system deflection electrode body 11 is combined to form an eight-pole electrode, the electron beam can be deflected with high precision because the deformation due to thermal expansion during use is small.

Further, since Pb is not contained, Pb is not reduced and deposited in a thermal environment, and thus the conductivity of the RuO ₂ system deflection electrode body 11 is not increased.

Next, with reference to FIG. 3, a manufacturing process of the deflection electrode according to the second embodiment of the present invention will be described. First, referring to FIG. 3A, a plate-shaped IrO ₂ -based deflection electrode body having a curved cross section obtained by grinding and polishing a composite in which IrO ₂ and borosilicate glass are mixed at a volume ratio of 1: 4, for example. 21 is formed. Incidentally, the resistivity of the IrO ₂ system deflection electrode body 21 in this case also becomes about 10 ⁻¹ Ω · cm by mixing borosilicate glass with IrO ₂ having a resistivity of −10 ⁻⁵ Ω · cm. .

Next, referring to FIG. 3B, the resist pattern (not shown) is used as a mask, and the thickness is, for example, 10 by the sputtering method.
A Cr adhesion improving layer 22 having a thickness of 0 nm is formed, and then a Ni layer having a thickness of, for example, 200 nm is formed by electroless plating.
The barrier layer 23 is formed.

Next, referring to FIG. 3C, the Ni barrier layer 23 is formed by electroless plating.
After the Au plating layer 24 having a thickness of, for example, 2 μm is formed thereon, the resist pattern is removed and unnecessary deposits deposited on the resist pattern are lifted off.

Next, referring to FIG. 3D, a Pb-Sn solder 25 is formed on the Au plated layer 24, and a voltage is applied to the IrO ₂ system deflection electrode main body 21 using the Pb-Sn solder 25. The basic structure of the deflection electrode is completed by connecting with the lead wire 26.
After that, an electrostatic deflection type sub-deflector can be obtained by arranging eight deflection electrodes formed in this way at equal intervals on the circumference to form an eight-pole electrode.

Also in this case, as in the first embodiment, a metallized layer having a uniform film thickness distribution and excellent adhesion strength and solder wettability can be formed. Also, Ir
The O ₂ system deflection electrode body 21 is also the RuO ₂ system deflection electrode body 11
Similarly, the oxidation does not change the resistivity,
Good heat resistance can be obtained.

Although the respective embodiments of the present invention have been described above, the present invention is not limited to the configurations described in the respective embodiments, and various modifications can be made. For example, in each of the above-mentioned embodiments, the adhesion improving layer is formed by the sputtering method, but it may be formed by another physical vapor deposition method such as a vacuum vapor deposition method.

Although Ti or Cr is used as the adhesion improving layer in each of the above-mentioned embodiments, the adhesion improving layer is not limited to Ti or Cr, and Zr or Ni may be used.

In each of the above embodiments, the Au plating layer is used as the connection metallization layer.
Not limited to Au, Cu, Ni, Pt, and Ag having good Pb-Sn solder wettability may be used, and the film forming method may be electrolytic plating instead of electroless plating. The method may be used.

In each of the above embodiments, P
Although a t barrier layer or a Ni barrier layer is used, such a barrier layer is not always necessary depending on the material of the metallizing layer for connection. For example, when Ni is used, the barrier layer is unnecessary. Even when Au or the like is used, the barrier layer is not always necessary when the connection metallization layer is formed thicker than usual.

In each of the above embodiments, RuO ₂ or IrO ₂ is used as the conductive oxide forming the deflecting electrode body, but it is not limited to RuO ₂ or IrO ₂ , and ReO ₂ May be used.

Furthermore, conductive perovskite oxides such as SrVO ₃ , CaVO ₃ , LaTiO ₃ , and SrMo are used.
O ₃ , CaMoO ₃ , SrCrO ₃ , CaCrO ₃ , L
aVO ₃ , GdVO ₃ , SrMnO ₃ , CaMnO ₃ ,
NiCrO ₃ , BiCrO ₃ , LaCrO ₃ , LnCr
O ₃ , SrRuO ₃ , SrFeO ₃ , BaRuO ₃ , L
aMnO ₃ , LnMnO ₃ , LaFeO ₃ , LnFeO
₃ , LaCoO ₃ , LaRhO ₃ , LaNiO ₃ , Pb
RuO ₃ , Bi ₂ Ru ₂ O ₇ , LaTaO ₃ , BiRu
O ₃ may also be used. However, magnetic materials such as Fe, Co, and Ni are unsuitable when used as a deflection electrode that constitutes a sub-deflector of an electron beam exposure apparatus.

In each of the above-mentioned embodiments, borosilicate glass is used as a sintering aid for the conductive oxide ceramics constituting the deflecting electrode body, but it is not limited to borosilicate glass. Pb when the softening point is 400 ° C or higher
It is also possible to use other known glass that does not contain. However, there is no problem even if such a glass is mixed with a glass containing a small amount of Pb component and used.

Further, in each of the above-mentioned embodiments, the deflection electrode is explained as the deflection electrode which constitutes the sub-deflector of the electron beam exposure apparatus, but it is not limited to the electron beam exposure apparatus and the electron microscope. It may be used as an electrostatic deflection electrode of another charged beam irradiation apparatus such as the above, and is particularly suitable as an electrostatic deflection electrode operated in the presence of a magnetic field.

Now, referring again to FIG. 1, detailed features of the present invention will be described. 1 (a) and 1 (b) (Supplementary Note 1) At least Ti, Cr, Zr, and Ni are formed on the surface of the deflection electrode body 2 made of ceramics composed of a conductive oxide and a sintering aid. An adhesive metallization layer 3 which is made of a conductive material containing at least one of Cu, Ni, Au, Pt and A
a conductive material including at least one of g,
Consisting connection metallization layer 4 which leads are connected, conductive ceramics deflection electrodes, characterized in that a metallized layer of a multilayer structure for connecting a lead wire. (Supplementary Note 2) The conductive oxide is RuO ₂ , Re.
O ₂ , IrO ₂ , SrVO ₃ , CaVO ₃ , LaTiO
₃ , SrMoO ₃ , CaMoO ₃ , SrCrO ₃ , Ca
CrO ₃ , LaVO ₃ , GdVO ₃ , SrMnO ₃ , C
aMnO ₃ , NiCrO ₃ , BiCrO ₃ , LaCrO
₃ , LnCrO ₃ , SrRuO ₃ , SrFeO ₃ , Ba
RuO ₃ , LaMnO ₃ , LnMnO ₃ , LaFe
O ₃ , LnFeO ₃ , LaCoO ₃ , LaRhO ₃ , L
aNiO ₃ , PbRuO ₃ , Bi ₂ Ru ₂ O ₇ , LaT
The conductive ceramic deflection electrode according to appendix 1, wherein at least one of aO ₃ and BiRuO ₃ is contained. (Supplementary Note 3) As a sintering aid for a ceramic comprising the above conductive oxide and a sintering aid, glass having a softening point of 400 ° C. or higher and containing no lead component is mainly used. The conductive ceramic deflection electrode according to Supplementary Note 1 or 2. (Supplementary Note 4) The specific electric resistance value of the ceramic composed of the conductive oxide and the sintering aid is 10 ⁻⁴ to 10 ⁴ Ω · cm.
And the coefficient of thermal expansion is 10 ⁻⁵ / ° C. or less, the conductive ceramic deflection electrode according to any one of appendices 1 to 3. (Supplementary Note 5) Any one of Supplementary Notes 1 to 4, wherein the adhesion metallized layer 3 is a physical vapor deposition layer.
The electrically conductive ceramics deflection electrode according to [4]. (Supplementary note 6) The conductive ceramic deflection electrode according to any one of supplementary notes 1 to 5, wherein the connection metallization layer 4 is a plating film. (Supplementary Note 7) The conductive ceramics deflection electrode according to any one of Supplementary Notes 1 to 6, wherein the deflection electrode is a deflection electrode that constitutes the sub deflector 1 of the electron beam exposure apparatus.

[0051]

According to the present invention, since the conductive ceramics, which is the constituent material of the deflection electrode, is composed of the conductive oxide and the glass, the deflection electrode does not oxidize and the resistance value does not change. Further, since the metallized layer formed on the surface of the deflecting electrode having a curved shape is formed by a normal film forming process, the metallized layer is excellent in film thickness uniformity, adhesion, and solder wettability. This makes it possible to operate a deflector such as a sub-deflector of an electron beam exposure apparatus with high accuracy, and thus contributes to high performance of a charged beam irradiation apparatus such as an electron beam exposure apparatus.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a principle configuration of the present invention.

FIG. 2 is an explanatory diagram of a manufacturing process of the deflection electrode according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram of a manufacturing process of the deflection electrode according to the first embodiment of the invention.

FIG. 4 is a conceptual configuration diagram of an electron beam exposure apparatus.

[Explanation of symbols]

1 Sub-deflector 2 Deflection electrode body 3 Adhesion metallization layer 4 Connection metallization layer 11 RuO ₂ system deflection electrode body 12 Ti adhesion improvement layer 13 Pt barrier layer 14 Au plating layer 15 Pb-Sn solder 16 Lead wire 21 IrO ₂ system deflection Electrode body 22 Cr adhesion improving layer 33 Ni barrier layer 24 Au plating layer 25 Pb-Sn solder 26 Lead wire 31 LaB ₆ Electron gun 32 Aperture 33 Lens 34 Lens 35 Block mask 36 Lens 37 Blanker 38 Lens 39 Lens 40 Sub-deflector 41 Main deflector 42 Lens 43 Wafer 44 Immersion lens 45 Electron beam

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 2001-307671 (JP, A) JP 2000-106117 (JP, A) JP 2000-11937 (JP, A) JP 62-103944 (JP , A) JP 8-83587 (JP, A) JP 5-276549 (JP, A) JP 2000-200575 (JP, A) JP 9-50969 (JP, A) (58) Survey Areas (Int.Cl. ⁷ , DB name) H01J 37/147 H01J 37/305 H01L 21/027

Claims (5)

(57) [Claims] 1. A conductive material containing at least one of Ti, Cr, Zr, and Ni on the surface of a deflection electrode body made of ceramics composed of a conductive oxide and a sintering aid. A contact metallization layer, which is in direct contact with the deflection electrode body, and Cu, Ni, Au, Pt, A
a conductive material including at least one of g,
Consisting of a connection metallization layer to which the lead wire is connected ,
A conductive ceramic deflection electrode, characterized in that a metallized layer having a multilayer structure for connecting lead wires is provided. 2. A softening point of 400.degree. C. as the sintering aid of ceramics comprising the conductive oxide and the sintering aid.
The conductive ceramics deflection electrode according to claim 1, wherein the glass mainly containing the above-mentioned lead-free glass is used. 3. The intrinsic electric resistance value of the ceramic comprising the conductive oxide and the sintering aid is 10 ⁻⁴ to 10 ⁴ Ω · c.
The conductive ceramic deflection electrode according to claim 1 or 2, wherein m is a coefficient of thermal expansion and is 10 ^-5 / ° C or less. 4. The conductive ceramic deflection electrode according to claim 1, wherein the adhesion metallization layer is a physical vapor deposition layer. 5. The conductive ceramic deflection electrode according to claim 1, wherein the connection metallization layer is a plating film.