JPH0443627A - Charged particle beam lithography equipment - Google Patents

Abstract

PURPOSE:To precisely reproduce drawing position, by detecting always the position of a charged particle beam with an electromagnetic field detector installed between an objective and a specimen, and feeding back the detection result to a deflection system. CONSTITUTION:A charged particle beam lithography equipment is equipped with an electromagnetic field detector 8 between an objective 5 and a specimen 7; an electromagnetic field generated by the flow of a charged particle beam is measured and detected by the detector 8; the position of the charged particle beam is always detected; the position signal is fed back to a deflection system, thereby correcting the beam position. In the case of drawing a practical specimen 7, an alignment mark on the specimen is detected; data such as on scaling and rotation are taken in and calculated with stored data regarding a reference specimen. Thereby accurate patterning is enabled on a practical specimen 7, while scaling, rotation, etc., are considered.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a charged beam lithography apparatus, and particularly to a charged beam lithography apparatus that reproduces a lithography position with high precision.

[Prior Art] In a conventional charged beam lithography apparatus, taking an electron beam lithography apparatus as an example, as shown in FIG. Projection lens; 3. Second forming aperture4. It is converged by passing through the objective lens 5, and is irradiated and drawn onto the sample 7I- by the deflector 6. For example, this device is known in Japanese Patent Publication No. 62-35263,
3451 (disclosed in, F et al.

[Problem to be solved by the invention] In the conventional charged beam drawing bag RL, drawing is performed by deflecting the beam, but in order to measure and confirm the position of the beam, it is necessary to check the pattern after drawing. In addition, it is necessary to draw and check several times in order to make corrections, which not only takes time, but also poses problems such as difficulty in obtaining desired pattern accuracy.

SUMMARY OF THE INVENTION An object of the present invention is to provide a charged beam drawing apparatus which solves the above-mentioned problems by measuring and confirming the position of the beam.

[Means for Solving the Problems j To achieve the above object, 1. A charged beam lithography apparatus according to the present invention includes an electromagnetic field detector and a deflector, and focuses a charged beam on a sample surface. A charged beam drawing device for exposing a pattern, wherein the electromagnetic field detector measures the position of the charged beam on the sample surface by measuring the electromagnetic field generated by the charged beam, and the deflector is configured to measure the position of the charged beam on the sample surface. The position of the charged beam is corrected to a set position based on a position signal from an electromagnetic field detector, and the electromagnetic field detectors are arranged in pairs on both sides of the charged beam axis. and has at least two pairs of electromagnetic field detectors.

[Function J] As shown in FIG. 1, the charged beam drawing apparatus of the present invention has the following features:
An electromagnetic field detector 8 is provided between the objective lens 6 and the sample 7, and the electromagnetic field generated when the charged beam flows is detected by the detector 8.
The beam position is corrected by constantly detecting the position of the charged beam and feeding back the position signal to the deflection system.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a configuration diagram showing an embodiment in which the present invention is applied to an electron beam lithography apparatus.

In the figure, the electron gun 1 is installed above the sample 7 and facing downward, and between the electron gun 1 and the sample 7 there is an axis of the electron beam (charged beam) from the electron gun 1. along the blanking electrode 9° first forming aperture 2. Projection lens 3. Second forming aperture 4° objective lens 5. Deflector 6. Electromagnetic field detectors 8 are arranged in sequence. As shown in FIG. 2, the electromagnetic field detector 8 has two sets of electromagnetic field detectors 8a and 8b, 8c and 8d arranged in pairs on both sides of the electron beam 10 in the XY force directions. There is. The electromagnetic field detector 8 measures changes in the magnetic field caused by the electron beam 10 and detects the electron beam 10.
It detects the position of The deflector 6 has an electron beam 10
The electron beam 10 is arranged in the XY force direction with the center at the center, and the electron beam 10 is deflected based on the position signal from the electromagnetic field detector 8 to perform position correction.

As shown in FIG. 1, after the electron beam emitted from the electron gun 1 passes through the first forming aperture 2, it is focused by the projection lens 3 onto the second forming aperture 4J-. This second forming aperture 4
The electron beam formed into a desired shape is further passed through an objective lens 5.
is focused on the sample 7 by. The electron beam focused on the sample 7'2 is deflected to an arbitrary position on the sample 71- by the deflectors 6 arranged in the X and Y force directions, and when a predetermined exposure amount is reached, the electron beam is blocked by the blanking electrode 9. By doing so, a desired pattern can be drawn on the sample 7L.

The position of the electron beam when the electron beam is deflected in this way is
The electromagnetic field generated when the electron beam passes is measured and detected by electromagnetic field detectors 8 arranged in each of the X and Y force directions. As shown in FIG. 2, the electromagnetic field detector 8 has two sets of electromagnetic field detectors 8a, 8b, 8c, and 8d arranged in the XY force directions. 1i
For example, coils are used as the magnetic field detectors 8a to 8d.

As shown in FIG. 2, a magnetic field is generated around the electron beam 1o. In a charged beam lithography system, the beam is frequently turned on and off, causing a displacement in the magnetic field. When the electromagnetic field detectors 8a-8d detect this displacement of the magnetic field, it is output as a change in current. If the position of the electron beam 10 is equidistant from the electromagnetic field detectors 8.3 to 8d, each detector will come out in the same way, but if they are not equidistant, a difference will occur in the output. In this way, in order to determine the absolute position of the heavy f-ray 1o using an electromagnetic field detector, first the electron beam 1o is
All you have to do is detect and find the position of and store it.

Next, when drawing the actual trial 47, detect and scale the alignment mark of 1 wipe 7L.

Import data such as rotation, base 1'$1! By calculating together with the data stored in the sample, it is possible to perform accurate patterning on the actual sample 7F at 1-, taking into account scaling, rotation, etc.

Further, even during normal drawing, the position of the electron beam is constantly detected and the position information is fed back to the deflector 6, so the reproducibility of the drawing position is extremely high.

In the above embodiment, two pairs of electromagnetic field detectors are used in the XY force directions, but if four pairs are used on eight sides, the processing speed will be slower, but the accuracy of electron beam position correction will be further improved.

Further, although a variable mold type has been described as an example of the electron beam lithography apparatus, the same applies to a Gaussian beam type.

In the embodiment, an example in which the present invention is applied to an electron beam lithography apparatus is shown, but the present invention can be similarly applied to a charged particle beam lithography apparatus. In this case, the charged particle beam lithography apparatus only uses an ion gun using liquid metal instead of the electron gun 1, and the other configuration is as shown in FIG. Since an electromagnetic field is generated even in the case of an ion beam, the same effect as shown in the above embodiment can be obtained.

[Effect of the Invention 1] As explained above, the present invention constantly detects the position of the charged beam using the electromagnetic field detector provided between the objective lens and the sample, and provides feedback to the deflection system. If carried out, it has the effect that stable drawing position reproduction accuracy can be obtained over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a charged beam drawing apparatus according to an embodiment of the present invention, FIG. 2 is a block diagram showing an electromagnetic field detector, and FIG. 3 is a block diagram showing a conventional charged beam drawing apparatus.

Claims (2)

[Claims] (1) A charged beam drawing device that has an electromagnetic field detector and a deflector and exposes a pattern by focusing a charged beam on a sample surface, and the electromagnetic field detector measures the electromagnetic field generated by the charged beam. The position of the charged beam on the sample surface is measured by the deflector, and the deflector corrects the position of the charged beam to a set position based on the position signal from the electromagnetic field detector. A charged beam lithography device featuring: (2) The electromagnetic field detector is arranged in pairs on both sides of the charged beam axis, and has at least two pairs of electromagnetic field detectors. A charged beam lithography apparatus according to item (1).