JPH04186351A - Cleaning of reticle - Google Patents

Abstract

PURPOSE:To improve the cleanliness of a reticle by radiating the ultraviolet rays on the obverse and reverse surfaces of the reticle. CONSTITUTION:A reticle 3 supported on a reticle arm 4 is introduced into an ultraviolet ray radiation box 14 in the foreprocessing, and radiated for a certain time by an ultraviolet ray lamp 6. Then, the reticle 3 is transferred into a reticle cleaning box 15, and the surface of the reticle is rubbed by the revolution of a cleaning brush 2, allowing cleaning liquid 11 to flow on the surface of the reticle 3, and the surface of the reticle is washed by vertically moving the reticle arm 4, and rubbed by the cleaning brush 2, allowing pure water to flow, and then the cleaning liquid 1 is removed. Accordingly, the surface having the water repellency becomes hydrophilic because the chemically organic substance is decomposed, and the affinity with the cleaning liquid is improved, and the dust adhering on the pattern edge part can be removed easily. Accordingly, the cleanliness of the surface of the reticle can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for cleaning a reticle used in a manufacturing process of a semiconductor device.

[Conventional technology]

In the conventional reticle cleaning method, the reticle surface was cleaned by moving the reticle up and down so that the surface of the reticle was in contact with a cleaning brush that continued to rotate in a fixed direction while flowing a cleaning solution.

[Problem to be solved by the invention]

Conventional reticle cleaning methods use a cleaning brush to physically remove dust and dirt adhering to the reticle surface, but when it comes to small particles, the brush rotates in a fixed direction. If dirt is trapped on one side of the pattern edge of the chrome surface of the reticle and cannot be removed, or if it is organic matter, the reticle surface is in a water-twisted state.
There was a problem that the cleanliness of the reticle surface was not sufficient, such as poor compatibility with the cleaning solution and complete removal in some cases. Therefore, when such a reticle is used to perform projection reduction exposure on a semiconductor substrate, defects such as pattern shorts may occur in the formed pattern, reducing the yield and reliability of semiconductor devices. There was a problem.

An object of the present invention is to provide a reticle cleaning method that improves the degree of reticle cleaning.

[Means to solve the problem]

The reticle cleaning method of the present invention includes a step of cleaning the reticle surface with a cleaning brush to remove dust and dirt without flowing a cleaning solution, and a step of irradiating the front and back surfaces of the reticle with ultraviolet rays. It consists of:

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

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

As shown in FIG. 1, the reticle 3 supported by the reticle arm 4 is first taken into an ultraviolet irradiation box 14 as a pretreatment and is irradiated with an ultraviolet lamp 6 for a certain period of time. During this time, since 03 is generated inside the ultraviolet irradiation box 14, the 03 is exhausted through the exhaust pipe 13. Next, the reticle 3 is moved into the reticle cleaning box 15, and while the cleaning liquid 11 is flowing onto the surface of the reticle 3, the cleaning brush 2 is rotated to scrub the surface of the reticle, and the reticle arm 4 is moved up and down to clean the reticle 3. After cleaning the surface, the cleaning liquid 1 is removed by rubbing with a cleaning brush 2 while running pure water.

Next, the reticle 3 is moved into a drying box 12, and the moisture on the surface of the reticle 3 is removed using alcohol vapor to dry the surface.

〔Effect of the invention〕

As explained above, in the present invention, by irradiating the reticle surface with ultraviolet rays prior to cleaning, the water-repellent surface chemically decomposes organic substances, becomes hydrophilic, and improves compatibility with the cleaning liquid. It became possible to easily remove dust adhering to the pattern edges.

At the same time, as mentioned earlier, oil stains can also be broken down.

In addition to these effects, the cleanliness of the reticle surface can be improved by the synergistic effect of physically cleaning the reticle surface using a cleaning brush. These effects make it possible to reduce defects in the pattern projected and reduced by exposure on the semiconductor substrate, and the IC
can improve yield and quality.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention 9 1...Cleaning liquid, 2...Cleaning brush, 3...Reticle, 4...Reticle carrying arm, 5...Cleaning liquid discharge Tube, 6... Ultraviolet lamp, 7... Pure water, 8... Heater, 9... Alcohol, 10... Alcohol discharge pipe, 11... Cooling tube, 12... Drying box, 13
...Exhaust pipe, 14...Ultraviolet irradiation box, 15.
...Reticle cleaning box. Agent Patent Attorney Otsuki Uchihara 1 Figure

Claims (1)

[Claims] A reticle cleaning method comprising the step of cleaning the reticle surface with a cleaning brush to remove dust and dirt while flowing a cleaning solution, the reticle cleaning method comprising the step of irradiating the front and back surfaces of the reticle with ultraviolet rays. Cleaning method.