JPH0797550B2 - Spin development method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a spin developing method, and more particularly to a spin developing method for a large substrate.

[Conventional technology]

The conventional spin developing method is generally a method in which a developing solution is dropped to carry out a developing treatment while the substrate is rotated at a predetermined rotation speed.

FIG. 3 is a time chart for explaining a conventional example. From the start A of dropping a predetermined developing solution to the end of development and a start C of rinsing, development is performed at a predetermined rotation speed of 450 rpm.

In such a conventional spin developing method, since the developing solution 2 is dropped while rotating the substrate 1 at a predetermined rotation speed, the developing solution 2 flows in a striae-like manner and the developing solution 2 is evenly distributed over the entire surface of the substrate 1. Therefore, a uniform pattern cannot be formed on the entire surface of the substrate 1.

FIG. 4 is a plan view showing the flow of the developing solution on the substrate by the spin developing method shown in FIG. 3, and it can be seen that the developing solution 2 flows in a striae.

FIG. 5 is a graph showing the relationship between the flow surface height H of the developing solution on the substrate 1 and the substrate circumferential position θ when the substrate 1 has a radius of 60 mm.

If the developing solution flows in a striae like this, the developing solution cannot be uniformly supplied to the entire surface of the substrate, so that a uniform pattern cannot be formed on the entire surface of the substrate.

Further, it is possible to reduce the flow of the striae-like developer 2 by decreasing the number of rotations, but in this case, the fresh developer 2 is not supplied to the outer peripheral portion of the substrate 1 and the substrate 1
Since the inner peripheral portion and the outer peripheral portion have different pattern shapes, it is still impossible to form a uniform pattern on the entire surface of the substrate 1.

[Problems to be Solved by the Invention]

However, in the above-described conventional spin developing method as described above, since the developing solution having the predetermined concentration is dropped on the substrate having the predetermined number of rotations, the developing solution flows in a striae, which hinders the formation of a uniform pattern. There is a drawback that is done.

[Means for Solving the Problems]

In the spin developing method of the present invention, first, a developing solution having a relatively low concentration is dropped while the substrate is rotated at a relatively low speed, the developing solution is spread over the entire surface of the substrate, and then the number of rotations is increased and dropped. It consists of a two-step development process in which the developer is switched from the first developer to a developer with a standard concentration. By adding the treatment with the first low-concentration developer, the developer with the next standard concentration is evenly distributed on the substrate. It is configured so that the development spreads uniformly over the entire substrate.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a time chart for explaining one embodiment of the present invention.

In the spin developing method shown in FIG. 1, a glass substrate 1 having an outer diameter of 220 mm and having a film thickness of 1200 Å coated with a photoresist (trade name: MP S1350J) manufactured by Shipley Co. is rotated at a rotation speed of 150 rpm in the first development step. On the other hand, the developer 2 manufactured by Shipley Co., Ltd. [trade name: MP Developer] is diluted to a normality of 0.02, and the developer 2 is dropped on the rotating glass substrate.

After the lapse of 10 seconds, in the second developing step, the rotation speed is increased to 450 rpm, the developing solution 2 having a normality of 0.20 is dropped, and further development is performed for 70 seconds.

The surface of the substrate has already been covered with developer 2 with normality 0.02,
Since the affinity between the surface of the substrate 1 and the developer 2 is remarkably increased, the striation flow of the developer 2 when the developer 2 having a normality of 0.2 is dropped is extremely small.

FIG. 2 shows the developer 2 on the substrate 1 when the radius of the substrate 1 is 60 mm.
5 is a graph showing the relationship between the liquid level height H and the substrate circumferential position θ.

Comparing this with the conventional method shown in FIG. 5, it can be seen that the fluctuation of the liquid level height H of the developer 2 on the substrate 1 is small.

Therefore, since the developing solution 2 is uniformly supplied to the entire surface of the substrate 1, a uniform pattern can be formed on the entire surface of the substrate 1.

〔The invention's effect〕

In the spin developing method of the present invention, while rotating the substrate at a first rotation speed lower than a predetermined rotation speed, a low-concentration developer is dropped to increase the affinity between the substrate surface and the developer, and then the rotation speed. Is increased to a predetermined second number of revolutions and a developing solution having a predetermined concentration is dropped to develop, so that the developing solution can be less likely to flow in a striae, so that the developing solution can be uniformly supplied to the entire surface of the substrate, so that the entire surface of the substrate is uniformly distributed. There is an effect that various patterns can be formed.

[Brief description of drawings]

FIG. 1 is a time chart for explaining an embodiment of the present invention, FIG. 2 is a graph showing the relationship between the circumferential position of the substrate and the liquid level of the developing solution in the embodiment shown in FIG. 1, and FIG. FIG. 4 is a time chart for explaining an example of the conventional art, FIG. 4 is a plan view for explaining the flow of the developing solution on the substrate in the conventional example shown in FIG. 3, and FIG. 5 is shown in FIG. 7 is a graph showing the relationship between the circumferential position of the substrate and the liquid surface height of the developer in the conventional example. 1 ... Substrate, 2 ... Developer, A, A ', B ... Drip start, C,
C '... start of rinsing, t ... development time, H ... level of liquid,
θ: Circumferential position of substrate.

Claims (1)

[Claims] 1. A first developing solution having a concentration lower than a standard concentration is dropped onto the principal surface while rotating a substrate having at least one principal surface at a first rotation speed lower than a standard speed. A developing step and a second developing step of dropping the second developing solution having the standard concentration on the main surface while rotating the substrate at the second rotation speed which is the standard speed. Spin developing method.