KR100585049B1 - Improved Method and Apparatus for Develop Process in Fabricating Semiconductor - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing process, and more particularly, to a developing method and a developing apparatus for effectively removing by-products generated in a developing operation performed after an exposure operation of a lithography process. According to the present invention, the step of forming a puddle by discharging the developer while rotating the wafer at a low speed (S10), the step of removing the by-products by rotating the wafer at high speed (S11), by discharging the deionized water while rotating the wafer at a low speed Removing by-products (S12), stopping supply of deionized water and performing a high speed rotation to dry the wafer (S13), discharging a developer while rotating the wafer at a low speed to form a puddle (S14), a wafer Rotation at high speed to remove the by-products (S15), the development room comprising the step of distributing and washing the deionized water while rotating the wafer at low speed (S16) and the step of rotating the wafer at high speed to dry (S17) and An apparatus for use is provided. According to the present invention by suppressing the mixing of the by-product B and the by-product A, it is possible to uniformize the critical line width and to prevent the deformation of the pattern by the resist, thereby improving the yield.

Developing process, by-products, developer, deionized water

Description

Improved development method in semiconductor process and apparatus used therein {Improved Method and Apparatus for Develop Process in Fabricating Semiconductor}             

1 is a flowchart summarizing a conventional developing process.

FIG. 2 is a diagram illustrating the properties of a photoresist on a substrate after an exposure step. FIG.

3 is a diagram illustrating a puddle state by a developer.

4 is a view for explaining the action of mixing the by-products A and B in the state shown in FIG.

5 illustrates how by-products adversely affect a semiconductor manufacturing process.

6 and 7 are electron micrographs showing that a defect occurred on the semiconductor substrate by the by-product B.

8 is a flowchart of a developing process according to an embodiment of the present invention.

9A is a perspective view of a coupling nozzle of a type in which a developing nozzle and a deionized water dispensing nozzle used in the developing process of the present invention are integrally combined;

9B is a bottom view of the engagement nozzle shown in FIG. 9A.

10A and 10B illustrate another embodiment of the unitary engagement nozzle shown in FIGS. 9A and 9B.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing process, and more particularly, to a developing method and a developing apparatus for effectively removing by-products generated in a developing operation performed after an exposure operation of a lithography process. .

In order to manufacture a semiconductor chip, a circuit is formed in a stacked manner, and each stacking step is called a layer, and a pattern required for each layer must be formed. In this case, a disk on which the necessary pattern is drawn is called a mask or a reticle. Lithography is a technique for creating shapes on the substrate on which the patterns drawn on the original plates are actually made.

The method of forming a desired pattern in the lithography process is as follows.

First, a surface treatment operation is performed to improve the adhesion of the wafer surface. In other words, HMDS (HexaMethylDiSilazane) is used to hydrophobize the surface, which prevents the pattern from falling off during development.

After the surface treatment is performed to increase the adhesion, thinner is used to remove particles from the surface and to smoothly apply the photoresist.

Thereafter, the solvent component in the resist is removed through a soft bake process, and the mask, in which the circuit of the desired pattern is drawn, is selectively exposed to the wavelength of the exposure apparatus. After exposure, the ID and wafer edge of the wafer are selectively exposed to remove the resist in the developing process.

Next, a post-exposure bake process is performed in which the effect is greatly different depending on the i-line and the deep ultra violet (DUV) resist. The post-exposure bake process in the eyeline resist is performed to minimize the standing wave effect, and in the case of DUV resist, it is an important process for forming a desired line width. After the baking process, the developing process leaves only the part where the actual pattern is to be formed and all other parts are removed. Depending on the pattern after the developing process, the progress of the baking process may be added or deleted.

A flow chart that outlines this general development process is shown in FIG. 1.

As shown in Fig. 1, in general, a typical developing process is a step of forming a puddle by discharging a developing solution while rotating a wafer at a low speed (S1), static and unexposed areas by a rotation of the wafer for a predetermined time. The regions are differentially etched to form a pattern on the film (S2) and the by-products generated on the patterned wafer are washed with deionized water (S3).

On the other hand, with the recent rapid development of circuit density and pattern line width reduction, there are many problems that affect the yield and quality of the lithography process. In the process of causing defects, defects and defects occurring after development are found by many engineers. There are many examples of defects in this category, such as irregularities in the state of development and defects caused by particles, which can be identified by the naked eye, and can be directly detected by visual defect inspection devices used in the manufacturing process. .

Visual inspection, which is visually inspected for defects and residues, called satellite and crown shapes, caused by the behavior of exposed and unexposed portions and developer residues that remain unreacted after the development process. It cannot be found through visual inspection equipment, but only by micro inspection equipment.

By-products generated in the developing process include the following.

The current development process presents many problems with the inability to control the dissolution properties of the resist in the static development stage, which plays a major role in CD (Critical Dimension) control and homogenization in development. From the mask bright field region and the dark field region, a wafer is formed on the wafer and an etched portion is formed, and CD non-uniformity is generated at a portion near the exposed portion of the wafer. The phenomenon is reported.

In the static development phase, three materials are present on the wafer: unreacted developer, resist by-products from exposed areas, and resist by-products from unexposed areas. Hereinafter, the by-products generated in the exposed area will be referred to as by-product A, and the by-products generated in the unexposed areas will be referred to as by-product B. By-products A and B do not exist individually but are mixed in the developer. In other words, by-product A and developer, and by-product B and developer.

FIG. 2 is a diagram illustrating the properties of the photoresist on the substrate after the exposure process.

As shown in FIG. 2, the polymer 20 in the area exposed in the exposure apparatus, that is, the resist becomes hydrophilic after a post exposure bake (PEB) process, and the unexposed portion 10 is hydrophobic. Will have the nature of.

3 is a view for explaining a puddle state by the developer.

As shown in FIG. 3, as the developing process is performed, the developer penetrates into the resist of the selectively exposed region 21 to generate the hydrophilic by-product A 22. On the other hand, the unexposed portion 11 dissolves a portion of the surface and generates hydrophobic by-product B 12. The developer 30 which has not reacted remains in the top layer.

4 is a view illustrating the action of mixing the by-products A and B in the state shown in FIG.

As shown in FIG. 4, the by-product A moves to the exposure area while the by-product A is mixed with the developer, and the by-product B and the by-product A are mixed.

FIG. 5 is a diagram illustrating how by-products adversely affect a semiconductor manufacturing process.

As shown in FIG. 5, the hydrophobic by-product B 13 is attached to the side where a pattern having hydrophobic properties is formed, resulting in CD heterogeneity. In addition, the by-product B (13) is again attached to the surface of the hydrophobic nature of the resist occurs to form a circular scum on the surface. This property is generated in a condition where a large number of by-products B of hydrophobic nature may occur, that is, an area in which the unexposed part of the exposure machine is distributed in a large area.

6 and 7 are electron micrographs showing that a defect occurred on the semiconductor substrate by the by-product B.

In particular, in order to form a fine gate pattern, an organic antireflection film is first applied to the wafer surface, and then a resist to be formed is applied. A by-product B generated in the developing process is attached to the organic antireflection film and remains in a crown shape. It leaves water. This is not seen in the gate pattern and is more observed in the areas coated with the organic anti-reflection film and found in micro-inspection after side well etching (FIG. 7).

In order to develop a solution to this problem, there is a great need to develop a development process capable of effectively removing by-products and to develop a device suitable for use therein.

The present invention was developed to solve the above conventional problems, and an object of the present invention is to develop a method and use thereof that can effectively remove by-products generated by the reaction of the hydrophobic resist with the developer during the development process It is to provide a device that is.

An object of the present invention as described above, the step of forming a puddle by discharging the developer while rotating the wafer at a low speed (S10), the step of removing the by-products by rotating the wafer at high speed (S11), while rotating the wafer at a low speed Discharging the deionized water by discharging the deionized water (S12), stopping supply of deionized water and performing a high speed rotation to dry the wafer (S13), and discharging the developer while rotating the wafer at a low speed to form a puddle ( S14), removing the by-products by rotating the wafer at high speed (S15), distributing and washing the deionized water while rotating the wafer at low speed (S16), and drying the wafer by rotating the wafer at high speed (S17). It is achieved by providing a developing method.

Here, the developer discharge nozzle used in the step S10 and step S14 and the deionized water discharge nozzle used in the step S13 and step S16 are integrally manufactured so that the nozzle is not replaced during the process. It is preferable that it is not necessary.

In addition, the object of the present invention as described above is a nozzle used for discharging a developing solution or deionized water onto a wafer in a developing step in a semiconductor manufacturing process, wherein a plurality of nozzle holes are formed on a bottom surface of a tubular member having a predetermined length. The upper part is formed with a deionized water discharge nozzle connected to the deionized water source, and a plurality of nozzle holes are formed at the bottom of the tubular member having a predetermined length, and the developer discharge nozzle connected to the developer supply source is integrally coupled to both sides side by side. In addition, it is more easily achieved by providing an integrally coupled nozzle capable of selectively using the deionized water discharge nozzle or the developer discharge nozzle.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

The present invention basically intends to construct a developing process in a direction of suppressing mixing of by-product B with by-product A.

8 is a flowchart of a developing process according to an embodiment of the present invention.

As shown in FIG. 8, the preferred development process according to the present invention includes discharging the developer while rotating the wafer at a low speed to form a puddle (S10), removing the byproducts by rotating the wafer at a high speed (S11), Discharging the deionized water by discharging the deionized water while rotating the wafer at low speed (S12), stopping the supply of deionized water and performing a high speed rotation to dry the wafer (S13), and discharging the developer while rotating the wafer at low speed. Forming a puddle (S14), rotating the wafer at high speed to remove the by-products (S15), distributing and washing the deionized water while rotating the wafer at low speed (S16), and drying the wafer by rotating the wafer at high speed. It is configured to include a step (S17).

In the embodiment according to the present invention, the number of puddle by the developer is different depending on the progress method, but washing with deionized water between the front puddle forming step (S10) and the rear puddle forming step (S14), between the puddle and puddle Washing with deionized water.

9A shows a combined nozzle in which the developing nozzle and the deionized water dispensing nozzle used in the developing process of the present invention are integrally combined, and FIG. 9B shows a bottom view of the combined nozzle shown in FIG. 9A.

As shown in FIG. 9A, the coupling nozzle 40 is manufactured in a form in which the developer dispensing nozzle 41 and the deionized water dispensing nozzle 42 are integrally coupled to each other. As shown in Fig. 9B, the nozzle holes 45 are generally arranged in a line at the bottom. Such a coupling nozzle 40 is very advantageous in shortening the process time when deionized water distribution and developer distribution are used frequently alternately as in the developing process according to the present invention.

10A and 10B show another embodiment of the unitary engagement nozzle shown in FIGS. 9A and 9B. The difference from the embodiment of the integrated coupling nozzle is that the size and number of nozzle holes are different.

The deionized water distribution between the two puddle forming steps S10 and S14 uses a deionized water nozzle 42 attached with the developing nozzle 41. The deionized water nozzle 42 attached with the developing nozzle 41 has a dispensing nozzle hole different from the main deionized water discharge device, and uses the nozzle 45 having the same aspect as the nozzle hole 45 through which the developer is discharged. Done. After the distribution of the deionized water and the removal of the by-products at high speed rotation, the developer can be supplied immediately.

The distribution pressure of the deionized water is controlled so as not to give a strong impact to the pattern by adjusting the discharged pressure as compared with the deionized water discharged from the main deionized water device.

The developing process involves always rotating the wafer at high speed before the deionized water is discharged, thereby creating a condition in which the byproducts are minimally mixed with the deionized water.

Conventionally, there was a problem in that a defect of a pattern was generated by the by-product B generated in the developing process, but according to the present invention, by suppressing the mixing of the by-product B and the by-product A, it is possible to uniformize the critical line width and The deformation can be prevented and thus the yield is improved.

In the above, certain preferred embodiments of the present invention have been illustrated and described. However, the present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art without departing from the gist of the present invention as claimed in the claims. will be.

Claims (3)

Discharging the developer while rotating the wafer at a low speed to form a puddle (S10); Rotating the wafer at high speed to remove by-products (S11); Discharging deionized water while rotating the wafer at a low speed to remove the byproduct (S12); Stopping supply of deionized water and performing a high speed rotation to dry the wafer (S13); Discharging the developer while rotating the wafer at a low speed to form a puddle (S14); Rotating the wafer at high speed to remove by-products (S15); Distributing and washing the deionized water while rotating the wafer at a low speed (S16); And And drying the wafer by rotating the wafer at high speed (S17). The method of claim 1, wherein the developer discharge nozzle used in the step (S10) and step (S14) and the deionized water discharge nozzle used in the step (S13) and step (S16) are made in one piece, The developing method characterized by not having to replace a nozzle. A nozzle used to discharge developer or deionized water onto a wafer in a developing step in a semiconductor manufacturing process, A plurality of nozzle holes are formed at the bottom of the tubular member having a predetermined length, and a nozzle for discharging the deionized water connected to the deionized water supply at the upper part thereof; A plurality of nozzle holes are formed in the bottom surface of the tubular member having a predetermined length, and a developer discharge nozzle connected to the developer supply source is integrally coupled to both sides side by side at the top thereof. And the deionized water discharge nozzle or the developer discharge nozzle can be selectively used.

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