JPS58159535A - Coater for photosensitive resin - Google Patents

Abstract

PURPOSE:To improve the yield of IC chips in the production of integrated circuits by providing an exposing mechanism for removing the positive type resist layer in the outside circumferential part of a substrate in a toric shape by a developing treatment. CONSTITUTION:A wafer 4 is placed on a wafer chuck 3, and is fixed by vacuum attraction or the like. Positive type resist is supplied through a resist supply nozzle 8. A rotary motor 1 is started, and the positive type resist is coated on the wafer by centrifugal forces. A light source 9 is lighted and only the outside circumferential part of the wafer is exposed by a luminous flux at the point of the time when the resist spreads over the entire part of the wafer. An ultra- high voltage mercury arc lamp is used for the light source. The wafer exposed only in the outside circumferential part after the coating of the resist is fed to the exposure stage for IC patterns through a prebaking stage, and in succession to said stage, the wafer is developed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photosensitive resin coating device used for manufacturing integrated channels, etc.

The degree of integration of integrated circuits has been increasing at an annual rate of 50φ. As the patterns constituting integrated circuits become finer and the chips become larger, the wafer four-light method is changing to the contact method, projection method, step-and-repeat method, X-ray beam exposure, @Research on exposure methods, etc. is also becoming more active. (Refer to [Super 1. Manufacturing Technology in the SI Era, etc., Seiko Materials, Separate Volume, 1981]) On the other hand, photosensitive resins (photoresists) used in the manufacture of integrated circuits, etc. are also negative-type photoresists. There is a shift from a method using a resist to a method using a positive type resistor l-'(r) with superior resolution.

In general, in one process of linking wafers, etc., a total of 20 to 50 substrates such as wafers are stored in a carrier case supported by four bars, and then transported to a destination. Transfer the rice to the carrier using a suitable method, for example, using a telescope or a belt, and then store the processed rice in the carrier again using the same transfer method.
l,ru. This operation includes cleaning, resist coating, baking, exposure, development, etching, impurity injection, resist 5II4, etc., and the wafer is dried and exposed to light.
Repeat as many times as necessary until the

However, when a positive resist is used in a wafer processing process, the novolak resin-based positive resist is inherently vulnerable to mechanical shock.

Therefore, as mentioned above (-2), when a wafer or the like is moved in and out of a carrier, the positive resist at the contact area between the wafer surface and the carrier is mechanically destroyed, and minute resist powder is generated. Resist powder generated from wafer processing is removed during wafer processing.

C0 (according to 101 times) it adheres to the chips and becomes a major cause of a decrease in the yield of I, C and chips.

The influence of defects caused by resist powder and dust on the yield is described in detail in ``Children's LSI Technology,'' ■Detailed Processing (Kokan Chosakukai), pages 79 to 82.

The present invention relates to a positive resist process.

1.To solve the problem of decreased C6 yield due to resist formation.

When the positive resist is applied, the contact area between the bar and the carrier is 1.0. Area that does not affect the yield of chips,
1. Focusing on the outer periphery of the wafer, the positive resist on the contact area is applied and removed in advance during the kjl11 process to prevent the generation of resist powder in the subsequent process. C, chip g! The overall purpose is to improve the yield of rice.

In other words, the present invention relates to a photosensitive resin coating apparatus characterized by being equipped with an exposure mechanism for selectively removing a positive resist I* on the outer periphery of a substrate in a circular manner through phenomenon processing. .

Hereinafter, the present invention will be explained in detail using the drawings.

Normally, in the wafer process, resist coating γ
After photolithography on the wafer, it is sent to the current I# process.
After being subjected to development processing, it is sent to subsequent steps such as etching.

Characteristics of the positive-type resist of the present invention: Immediately after coating the positive-type resist on the wafer, 1. death,
An appropriate area that does not affect the chip yield is exposed to light to make it soluble in a developer, and in the post-process development process, the annular area around the outer periphery of the wafer (where a positive resist layer is formed) is exposed to light. n
) 2i, e.

To provide a photosensitive resin coating device for removing resist regardless of the pattern of a chip and eliminating the source of resist powder from a wafer generated by ilJ with a carrier in a post process.

FIG. 1 is a cross-sectional view of a developing plate of a bar coated with a positive resist using a conventional coating device (f), and a resist +412 is formed on the entire surface of the wafer substrate 11. FIG. 2 is a cross-sectional view of a wafer treated in the same manner using the sound of the present invention, and a resist I@912 is formed in the area excluding the outer periphery of the wafer fill.

FIG. 3 schematically shows the apparatus of the invention. A spindle 2 is connected to a motor 1, and a wafer chuck 3 for holding a wafer is connected to the tip of the spindle. A wafer 4 is set on the wafer chuck 3 and moved there. The wafer chuck part 3 and the wafer 4 are connected to a circular cup 5.
Surrounded by. Further, a resist supply nozzle 8 is connected from the resist container 7 via a resist supply vibro. A light beam 10 for exposing the wafer outer circumference is provided by a light source 9
It occurs more.

The photosensitive resin coating apparatus in this embodiment is the same as the above-described metal fitting 1s, and the process of wafer processing using this metal fitting 1s is as follows.

Place the wafer S-4'e on the wafer chuck 3 and fix it by any suitable method, such as vacuum suction.

5- Subsequently, a positive resist is supplied via the resist supply nozzle 8. The rotary motor is started and the positive resist is applied onto the wafer by centrifugal force. The motor rotation time at this time is sufficient for the bath agent of the positive resist to evaporate, preferably from 30 seconds to 60 seconds.

When the positive resist has spread over the entire surface of the wafer, the light source 9 is turned on, and only the outer peripheral portion of the wafer is exposed to the light beam 10.

The light source has a wavelength range of 2500~, which is the sensitive wavelength range of positive resist.
It only needs to contain a wavelength of 4500x, and 5x on the wafer surface.
It is sufficient to obtain energy of about 0 to 200 mJ (millijoules). The light source used is an ultra-high pressure mercury lamp. In this case, the light beam IO may be taken directly from the light source 9, or an optical fiber may be used.

Alternatively, an optical system using all mirrors may be used.

The light beam 10 does not have to be circular, and only the outer circumference of the wafer is frozen within a suitable range.1. An A2 shape may be used as long as it can expose a range that does not affect the C0 chip yield. Also, the position of the light source.

When applying the resist, in order to avoid contamination with the resist,
A mechanism that aligns the light beam with the outer circumference of the □ bar only when the light is on may be used.

The wafers coated with resist and exposed only on the outer periphery in the above manner are subjected to a pre-baking process, with l, C,
It is sent to a pattern exposure process, and then subjected to a development process.

As shown in Figure 2, the outer periphery of the wafer is ■.

C. Regardless of pattern exposure, the positive resist is removed due to friction with the wafer carrier in the post-process.
The generation of resist powder is avoided.

In this way, the photosensitive resin coating apparatus according to the present invention can be used by extremely simple means without reducing throughput.
It is possible to completely suppress the generation of resist powder and improve the yield of integrated appositional chips. 1 hour.

Although this example has been explained using a wafer, it goes without saying that the present invention does not include substrates such as mask substrates.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a □ bar coated with resist using the conventional method. FIG. 2 is a cross-sectional view of a wafer coated with resist using the apparatus of the present invention. It is a political cross-sectional diagram showing an example. In the same figure, l...rotating motor, 2...
...Spindle, 3...Wafer chuck, 4...1 bar, 5...Cup, 6
...River/resist supply pipe, 7...Resist container, 8...Resist supply nozzle, 9...
... light source, 10 ... light flux, 11 ... group wafer, 12 ... resist l-.

Claims (1)

[Claims] We now have a one-light mechanism for selectively removing the positive resist 1- on the outer periphery of the four plates in a circular pattern through development processing! Features of photosensitive resin coating equipment.