JPS5838605Y2 - Rotary coating device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an apparatus for forming a uniform coating film of a viscous material on a predetermined substrate surface by a spin coating method, a so-called spin coating apparatus.

When etching the surface of a semiconductor or metal substrate,
A photosensitive coating (so-called photoresist coating) is attached to the surface of this substrate, and this coating is hardened by exposing it to a predetermined shape through an exposure mask.The surface of the substrate is then etched using this hard pattern as a mask. A construction method, the so-called photo-etching technique, is often used.

At this time, it is important to uniformly form the photoresist film in order to improve the processing accuracy of the object to be etched.

Conventionally, most coating devices have been used to form this type of film, and the outline of the device is to drop a viscous film-forming material onto the surface of a substrate placed on a rotating table, and then move the rotating table at high speed. It is rotated to create an even shape.

By the way, one problem with such a rotary coating device is that the residue of the film-forming material scattered by the rotation turns into mist particles and bounces off the scattering prevention wall around the rotary table, which creates minute particles on the surface to be coated. This makes it difficult to obtain a uniform coating.

This invention proposes a measure to solve the above-mentioned problems.

In summary, the device of this invention is an apparatus that drops a viscous material onto the surface of a substrate placed on a rotating table and forms a coating film on the surface of the substrate by rotation. An exhaust vane plate is fixed to a supported rotating shaft.

According to this device, the fog particles caused by the residue of the film-forming material scattered by the rotation are sent out by the above-mentioned exhaust vane, so that the minute particles formed by the deposition of the fog particles on the surface to be coated are There will be no unevenness.

Next, the device of this invention will be described in detail with reference to examples.

1 and 2 are a plan view and a side sectional view of the main parts of the apparatus on the real side of this invention. A uniform coating 3 is applied by dropping a forming material, for example, a photoresist film forming agent, and rotating it.

Note that this device is surrounded by a storage hood 4.

A feature of this device is that, as an exhaust means, an exhaust vane plate 5 is fixed to a rotating shaft that supports the rotating table 1 from below.

In this device, floating objects N in the space above the rotary table 1, especially
After the mist particles formed by the residue of the film-forming material collide with the inner wall surface of the storage hood 4 due to centrifugal force, they are sent downward and removed.

At this time, an intake duct may be provided below the exhaust vane 5, but this is not always necessary.

At this time, the inner wall surface of the storage hood 4 had an angle θ in a direction perpendicular to the plane of the rotary table, and good results were obtained when the angle θ was in a range of about 400 to 15 degrees.

This is because by tilting the inner wall surface of the hood, even if the mist particles of the film-forming material collide with the wall surface and are reflected, they tend to move in the exhaust direction from A-+B to C as shown in the figure. be.

Moreover, in this device, since the exhaust vane plate 5 is attached to the rotating shaft of the rotary table 10, the intake force increases with rotation, so that good results can be obtained regardless of the rotation speed.

As described in detail above, according to this device, the suspended particles of the film-forming material scattered during spin coating are removed by the exhaust vane provided on the rotating shaft below the rotating table. Therefore, it does not adhere to the substrate, and therefore the surface to be imprinted becomes smooth.

If this film is a photoresist, a photomask can be closely attached to it, so that the accuracy of exposure and resolution can be improved, and the accuracy of the substrate BO can be improved.

Moreover, since the photomask is not damaged by not touching the affected surface, the photomask can be used more efficiently and is economical.

[Brief explanation of the drawing]

FIGS. 1 and 2 are a plan view and a sectional side view of a spin coating device in one practical example of this invention. 1... Turntable, 2... Base, 3...
...Coating, 4... Storage hood, 5...
・Exhaust vane.

Claims (1)

[Scope of utility model registration request] In an apparatus in which a rotating table is arranged in a storage hood, a viscous material is dropped onto the surface of a substrate placed on the rotating table, and a coating film is formed on the surface of the substrate by rotation,
A rotary coating device, characterized in that an exhaust vane plate is fixed to a rotary shaft that supports the rotary table from below to send out atomized suspended matter generated around the rotary table to the outside.