JPS586133A - Forming device for minute pattern - Google Patents

Abstract

PURPOSE:To form the mask pattern directly without the application of a resist and the process of development by positioning a gas containing carbon near the forming section of the pattern when exposure and directly fixing the gas component to the surface to be processed by electron beams. CONSTITUTION:When the electron beams 6 are irradiated only to a specified section on a material to be processed in form that the predetermined pattern is drawn by an electrooptic system, the gas 10 containing carbon blown from a nozzle 7 is positioned around the material to be processed 4, and a condition that the gas collides with the surface to be processed at all times thermal agitation is brought. If electron rays are projected when the carbon gas collides with the solid surface, carbon gas molecules are baked to the solid surface and solidified through the reception of the energy of the electron rays. The carbon compounds 11 are grown in the extent which can be used as the mask patterns.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for forming a mask pattern used in microfabrication by photolithography.

As a conventional seed seed device, the one shown in Figure 1 has been used.

In the figure, % (1) is the electron gun, (2) is the second electron gun (1
) is an electron optical system for squeezing the electron beam emitted from the object and irradiating it onto a desired position on the workpiece; (3) is a chamber for evacuating the entire system; I) is the workpiece; (6) is a resist coated in advance on the workpiece (4) of ξ; (6) is an electron beam that is scanned to draw an arbitrary pattern on the workpiece surface by an electron optical system [); (7) represents the resist region altered by the electron beam, and the entire system is evacuated by an evacuation pump system (not shown) located at the bottom of the figure.

Next, the operation will be explained. Electron optical system (by illusion,
As shown in the diagram, only a specific portion of the workpiece is irradiated with electrons m (+1). Due to the ξ angle, the degree of polymerization of the resist (6) previously coated on the workpiece (4) changes only in the irradiated portion, resulting in a deteriorated layer (7). In this way, after forming an altered layer with a desired shape on the resist surface, the processed object is taken out of the vacuum chamber. For example, in the case of a positive resist - A desired mask pattern is formed on one surface of the workpiece by melting away the resist in the area. - Conventional electron beam exposure equipment can only perform exposure as described above. When actually forming a mask pattern for photolithography, it is necessary to apply a resist to the entire surface to be processed in advance, and a developing process is also added after exposure to dissolve unnecessary parts. This work was necessary. Furthermore, when the tg pre-light pattern is matched with the base pattern, the alignment accuracy tends to be inaccurate because about 11M is projected through the resist coated on the entire surface.

This invention was developed to eliminate the drawbacks of the conventional apparatus as described above, and involves interposing a carbon-containing gas near the pattern forming surface during exposure, and directly fixing the gas component to the surface to be processed using an electron beam. Accordingly, the present invention aims to provide a microfabrication device that can directly form a mask pattern without resist coating or development steps.

An embodiment of the present invention will be described below with reference to the drawings. Second
In the figure, (7) is a nozzle for spraying carbon-containing gas onto the surface to be processed in a vacuum chamber, and (8) is a variable nozzle for finely controlling the gas pressure supplied to (7) 4. type leak valve, (9) is a pipe that guides gas from the raw material gas cylinder (not shown), (A) is a schematic representation of the carbon-containing gas blown out from the nozzle (7)', ( (b) is a carbon compound layer formed as a result of the gas particles () being baked and solidified by electron beam irradiation.

The operation of the apparatus of the present invention configured as above will be explained below. In this device as well, the electron optical system irradiates only a specific part of the workpiece with an electron beam in a manner that draws a predetermined pattern, which is exactly the same as in the conventional device. No resist was applied to the surface of the object (4). Instead, the carbon-containing gas [phase] blown from the nozzle (7) when ejecting the electron beam (6) is present around the workpiece (4), A situation is created in which these gases constantly collide with the surface to be machined due to thermal motion.

When an electron beam is incident while carbon gas is centered on the surface of a solid, the carbon gas molecules receive the energy of the electron beam and are burned onto the solid surface lζ and become solid.

This phenomenon has been observed on a small scale due to the action of residual hydrocarbon molecules in vacuum, for example, when observing samples using an electron microscope, and has been known as the formation of surface contours due to electron beam irradiation. However, since gas molecules are intentionally supplied in this device, such carbon compound formation occurs on a large scale, resulting in (
(b) It grows easily to the extent that it can be used as a mask pattern. The film (b) has excellent adhesion to the processed surface and excellent resistance to chemicals, so it has superior properties as a mask material for photoetching compared to conventional resists. After etching, the mask can be easily removed using oxygen plasma, sulfuric acid, aqua regia, or the like. The gas used is hydrocarbon oil vapor with a high vapor pressure, or a secondary gas containing gas such as methane. Depending on the type of gas and the evacuation mechanism of the electron optical system, the optimum gas pressure during use may vary, or the pressure may be controlled by a valve (8). The rate of formation of hydrocarbon compounds increases as the gas concentration on the surface of the workpiece increases (however, the mean free path of the electron beam becomes shorter as the residual gas pressure increases), so the gas concentration cannot be unlimited.
It is not possible to reduce the temperature to ξ, and even if the differential pumping mechanism is devised to the maximum, the limit is 10"i Torr.On the other hand, as the degree of vacuum increases, the rate of carbon compound formation slows down and Above 1F'Torr, it becomes impossible to form a practically usable film.

In the above embodiment, a structure in which gas is blown through the nozzle (7) is shown, but it goes without saying that a structure in which the entire periphery of the workpiece is filled with gas at a constant aik may also be used.

As described above, according to the present invention, since a predetermined mask pattern is directly projected onto the processing surface using an electron beam, it is possible to omit processes such as cyst coating and development, and to produce high-precision photographs. This has the effect of forming an etching mask pattern.

[Brief explanation of drawings]

FIG. 1 is a schematic side sectional view showing a conventional electron beamless device, and the eleventh factor is a schematic thin sectional view showing a fine pattern forming device according to an embodiment of the present invention. In the figure, (1)... Electron gun, (IJ... Electron optical system, (4)... Workpiece, (6)... Electron beam Th (7)... Nozzle,・・Carbon-containing gas, (
b) It is a carbon compound layer. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Makoto Kuzuno - Figure 1

Claims (1)

[Claims] (1) An electron beam optical system that can be controlled to draw any planar figure on the workpiece, and an atmosphere near the workpiece that can be controlled freely within the range of 10-' to 10-''f6rl. (2) A fine pattern forming apparatus characterized by having a nozzle arranged in a shape that creates a high gas concentration atmosphere near the processing surface. A fine pattern forming apparatus according to claim H, item 1. (8) Claim #! 1 to 1, characterized in that a carbon-containing gas is used as the introduced gas. The fine pattern forming apparatus described above.