JPS59121926A - Charged beam exposure device - Google Patents

Abstract

PURPOSE:To enable to correct aberration of the focus, etc., of a charged beam exposure device by a method wherein an electrostatic lens not to affect an adverse influence to an electrostatic deflector is constructed in the deflector by itself. CONSTITUTION:An electrostatic deflector 10 is consisting of multisegmental electrodes 10a-10h, and earth electrodes 20, 21 are arranged at the upper and lower sides of the deflector electrode 10. The earth electrodes 20, 21 are connected to earth potential, and deflecting voltages and a focus correcting voltage Vf are applied to the respective electrodes of the deflector 10. A focus aberration lens is constructed by the voltage Vf and the earth electrodes 20, 21 at the same time with construction of deflecting faculty, and an electrostatic lens system having electric potential distribution is constructed to perform correction of the focus.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a charged beam exposure apparatus, and more particularly to an improvement in an electrostatic deflector used in an electron beam exposure apparatus or an ion beam exposure apparatus.

(2) Background of the technology As electronic devices become denser and more highly integrated, the spread due to scattering in materials is smaller than that of electron beam exposure equipment.
Ion beam exposure apparatuses capable of fine processing on the order of 1 μm have recently come into use.

An electrostatic deflector is used as a deflector in some of such electron beam exposure apparatuses and most of ion beam exposure apparatuses.

In particular, electrostatic deflectors are used in ion beam exposure apparatuses because the deflection width does not depend on the ion mass.

In such a deflector, when the deflection width is widened, astigmatism and focal aberration occur. Among these aberrations, ion beam exposure equipment that takes measures to correct astigmatism is known, but there is a need for ion beam exposure equipment or electron beam exposure equipment that corrects focal aberration. .

(3) Problems with conventional technology FIG. 1 is a configuration diagram of a conventional ion beam exposure apparatus.

FIG. 2 shows a cross-sectional view taken along line A-A in FIG.
In FIG. 1, 1. is an ion source such as gallium or water-curing lanthanum (LaB6) or a heat power source 3 in the column.
The ion beam emitted from the ion source 2 passes through a lens system 4 having an aperture and a blanking electrode 5, passes through an aperture lens 7, and is focused by an Einzel lens 8. A blanking voltage is applied to 6, and 9
An accelerating voltage, a focus voltage, etc. are applied to. Although not shown, these voltages are applied from the control circuit 14 through a digital-to-analog conversion circuit (hereinafter referred to as DAC), an amplifier circuit, and the like.

The ion beam 22 focused through the Einzel lens 8 is deflected by an electrostatic deflector 10 divided into a plurality of parts, and a pattern is drawn by irradiating the sample 12 on the stage 11 with the ion beam 22.

The electrostatic deflector 10 includes a control circuit 14 that is controlled by signals read from a memory in a computer 13, etc.
The digital control signal is converted into analog by the DAC 15 and added through the amplifier circuit 16.

The stage 11 is also moved by applying a voltage to the morph of the stage drive source 19 through the path of the control circuit 14, DAC 17, and amplifier circuit 18.

The electrostatic deflector electrode 10 in FIG. 2, which is a cross-sectional view taken along the line A-A in FIG. 1, is composed of, for example, eight electrodes.
, 10e has ±VY voltage, and electrodes 10c and 10g have ±VY voltage.
Vx voltage is applied to electrode 10b.

1/-6 (±Vy, ±VY) voltage is applied to 10f, 1/min (■C■γ) is applied to electrode 10d, and 1 is applied to electrode 10h.
A voltage of /6 (-VX + VY) is applied to form a deflection magnetic field.

However, if an attempt is made to widen the one deflection width with this configuration, astigmatism and focal aberration will naturally occur. If you want to eliminate such aberrations, you can configure an aberration correction lens near the electrostatic deflector, but since the deflector is an electrostatic type, the aberration correction lens placed close to the deflector may It had some drawbacks that had a negative impact.

(4) Purpose of the Invention In view of the above-mentioned conventional drawbacks, the present invention provides a charged beam exposure apparatus that can correct focal aberrations by configuring the electrostatic deflector itself with an electrostatic lens that does not adversely affect the electrostatic deflector. The purpose is to

(5) Structure of the Invention and the above-mentioned object according to the present invention is that in an electrostatic deflector for electron or ion beam exposure, ground electrodes are provided above and below the electrostatic deflector, and a plurality of divided electrostatic deflectors are provided. Deflection voltage G applied to the electrodes of the deflector.

A charging method characterized in that the same predetermined offset voltage is added to the deflection voltage number to form an electrostatic lens with the two ground electrodes and the electrostatic deflector electrode to correct focal aberration. Achieved by a beam exposure device.

(6) Embodiment of the Invention An embodiment of the present invention will be described below with reference to FIGS. 3(a) and 4.

3(al) and (b) are a side view and a potential distribution curve diagram of the electrostatic deflector 10 of the present invention, and FIG. 4 is a diagram of FIG. 3B-B.
'It is a cross-sectional view taken along the arrows.

FIG. 3(a) shows electrodes 10a and 10b which are divided into multiple parts (for example, divided into eight parts) and have the same configuration as the electrostatic deflector 10 shown in FIG.
, 10c, 10d, 10e, 10f.

10g and 10h, and ground electrodes 20 and 21 are disposed above and below the deflector electrode 10.

These electrodes are made of, for example, cylindrical phosphor bronze, the ground electrodes 20 and 21 are connected to the ground potential, and a voltage for deflection and a voltage vl for focus correction are applied to each electrode of the deflector 10.

That is, as shown in FIG. 4, which is a sectional view taken along line B-B' in FIG.
The electrode 10b receives a voltage of 1/T(■S+VY) + Vf, the electrode 10C receives a voltage of ■Me+Vf, and similarly 10d=1/-7'j(Vz-VY)+V$10 e
=-VY +V1 10 f = 147 (V-Vy) +V110 g
””V,,1. + Vfl 0 h=1/σ(V
,
．． Focus correction is performed by creating an electrostatic lens system composed of 21 and having a potential distribution as shown in FIG. 3(b). In the above embodiment, an ion beam exposure system was explained as an example, but it goes without saying that the present invention can be applied to an electrostatic deflection system such as an electron beam exposure system that performs drawing using an electromagnetic polarization system and an electrostatic deflection system. be.

The voltage actually applied as a deflection voltage to the electrostatic deflector is about 50V, and the voltage Vf applied to form the electrostatic lens is about 10 to 20V, so correction can be performed quickly. On the other hand, it is conceivable to perform focus correction by adding 10 to 20 V to the high voltage (~acceleration voltage, 20 KV) applied to the focusing lens system, but this is because high voltage is highly stable and has become a problem.

In practice this is impossible.

(6) Effects of the Invention Since the charged beam exposure apparatus of the present invention is configured and operates as described above, a single electrostatic deflector can function as a focus correction lens in addition to the function of a deflector. Therefore, it is possible to obtain an electrostatic deflector for charged beam exposure that does not adversely affect the deflector.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a conventional ion beam exposure apparatus. FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1, FIG. Figure fa) Electrode potential distribution diagram 5
FIG. 4 is a cross-sectional view taken along line BB' in FIG. 3, showing the relationship between applied voltages. l... Column, 2... Ion source, 5... Blanking electrode, 8... Einzel lens,
10... Electrostatic deflector, 11... Stage,
12... Sample, I3... Computer,
14...Control circuit, 15.17...DAC,
19... Stage drive unit, 20.21... Ground electrode.

Claims (1)

[Claims] In an electrostatic deflector for electron or ion beam exposure, grounding electrodes are installed above and below the electrostatic deflector to offset the deflection voltage applied to the electrodes of the electrostatic deflector, which is divided into multiple parts. A charged beam exposure apparatus characterized in that the same predetermined voltage is applied to the deflection voltage to form an electrostatic lens using the two ground electrodes and the electrostatic deflector electrode to correct focal aberration.