JPH02125607A - Sample holder for electron beam drawing equipment - Google Patents

Abstract

PURPOSE:To prevent the generation of magnetic field which deflects an electron beam for drawing by arranging a plurality of grounding plates or grounding pins around a sample holder, so as to surround the image drawing region of a retained sample substrate. CONSTITUTION:For example, grounding plates 3 composed of phosphor bronze, which come into contact with the metal film of a mask 2 are grounded, are arranged on the peripheral part of a sample holder 1, so as to surround an image drawing region 4 of a mask 2. When the mask 2 is retained by the sample holder 1, the grounding plates 3 are brought into contact with the metal film by spring energy, and a grounding region 5 is formed. When an electron beam is incident at any position of the image drawing region 4 of the mask 2, electrons continue to radially spread from an incidence point, and flow out from the nearest grounding region 5 through the grounding plate 3, so that the biasing of electron flow can be eliminated. Thereby, the generation of magnetic field which deflects the incidence position of electron beam can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sample holder for an electron beam lithography system used for manufacturing integrated circuit components, photomasks, computer circuit boards, and the like.

[Conventional technology]

An electron beam drawing device is a device that draws highly accurate wiring patterns and circuit patterns by irradiating an electron beam onto an electron beam-sensitive resist coated on a sample substrate such as a mask, wafer, or circuit board.

Conventionally, the sample holder used for mask lithography with this electron beam lithography system has a structure in which the mask 2 is inserted and inserted, as shown in FIG.
It can be fixed, and has a structure in which two grounding needles 3 are usually attached instead of one.

As shown in FIG. 5, a mask 2 consisting of a metal film 2B made of Cr or the like provided on a quartz plate 2A and an electron beam photoresist 2C is held on a sample holder 1, and then an electron beam 7 is applied. Although it is irradiated, the electron beam sensitive resist 2c
The structure is such that the charge of the electron beam 7 that has exposed the sample can be guided through the metal film 2B and the grounding needle 6 to the conductive sample holder 1 itself and removed.

[Problem to be solved by the invention]

However, when a pattern is drawn using the above-described conventional sample holder for an electron beam drawing apparatus, there is a drawback that the accuracy of the drawing position decreases as the amount of current of the electron beam increases, which will be described below.

(1) An electron beam drawing device with a beam width of several tens of microns has been developed for drawing circuit boards.

(2) From writing with a circular beam of 1 μm or less, one-shot writing of a large area using a variable shaped beam has been put into practical use.

(3) In order to form a pattern with higher precision, it is now necessary to use an electron beam photoresist with poor sensitivity.

(4) In order to improve drawing speed, the amount of incident electron beam per unit time has increased.

As shown in FIG. 6, the electron beam incident on the mask exposes the electron beam photoresist 2C at the incident point 8, spreads radially within the metal film 2B as shown by the arrow, and travels to the ground needle 6.
It gathers at the contact point 9.

The magnetic field 10 generated by this flow of electrons is as shown by the arrows in FIG. This magnetic field 10 becomes larger as the electron beam 7 becomes stronger and the distance between the incident point 8 and the contact point 9 becomes shorter, and it deflects the electron beam 7 to be drawn and moves the position of the incident point 8 downward in the figure. Further, this magnetic field 10 does not exist at the moment when the electron beam 7 first enters the magnetic field, but is generated when the electron beam 7 continues to enter the magnetic field 10. Therefore, it has a characteristic that it fluctuates as the electron beam 7 is interrupted and is difficult to correct.

[Means to solve the problem]

In the sample holder for an electron beam lithography system of the present invention, a plurality of ground plates or ground needles are provided at the periphery of the sample holder that holds a sample substrate on which an electron beam photoresist is formed so as to surround the drawing area of the sample substrate. It is something that

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a perspective view of a first embodiment of the present invention, showing a state in which a mask is held.

As explained in FIG. 5, the mask 2 is composed of a metal film 2B formed on a quartz plate 2A and an electron beam photoresist 2C. The grounding plate 3 made of bronze covers the drawing area 4 of the mask 2.
When the mask 2 is held on the sample holder 1, the ground plate 3 comes into contact with the metal film 2B due to the force of the spring, and as shown in FIG. form 5.

According to the first embodiment configured in this way, the mask 2
No matter where in the drawing area 4 the electron beam is incident, the electrons continue to spread radially from the point of incidence to the nearest ground class i! ! 15 and flows out through the ground plate 3, it is possible to eliminate unevenness in the flow of electrons, and the generation of a magnetic field that deflects the incident position of the electron beam can be extremely reduced.

FIG. 3 is a perspective view of a second embodiment of the present invention, in which a large number of grounding needles 3 are arranged on the sample holder 1 so as to surround the drawing range of the held mask 2. Also in this second embodiment, the electrons incident on the mask 2 can be spread radially and flowed out from the nearest grounding needle 3.

〔Effect of the invention〕

As explained above, the present invention provides a plurality of ground plates or ground needles around the sample holder so as to surround the drawing area of the held sample substrate, thereby generating a magnetic field that deflects the electron beam for drawing. This has the effect of being able to prevent.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the first embodiment of the present invention, and FIG. 2 is a perspective view of the first embodiment of the present invention.
A top view of the mask for explaining the effects of the embodiment 3.
The figure shows a perspective view of the second embodiment of the present invention, FIGS. 4 and 5 are perspective views and cross-sectional views of a conventional sample holder, and FIGS. 6 and 7 show electrons on a mask due to the incidence of an electron beam. FIG. 2 is a diagram showing the flow and magnetic field distribution. DESCRIPTION OF SYMBOLS 1... Sample holder, 2... Mask, 2A... Quartz plate, 2B... Metal film, 2C... Electron beam photoresist, 3... Ground plate, 4... Drawing area, 5... Grounding area, 6... Grounding needle, 7... Electron beam, 8... Incident point, 9... Contact line, 10... Magnetic field. No (*tenth hole / shadow! wa stage diagram shadow diagram

Claims (1)

[Claims] A sample for an electron beam lithography apparatus, characterized in that a plurality of ground plates or ground needles are provided at the periphery of a sample holder that holds a sample substrate on which an electron beam photoresist is formed, so as to surround the drawing area of the sample substrate. holder.