CN115966460A

CN115966460A - Method for improving developing quality of semiconductor

Info

Publication number: CN115966460A
Application number: CN202111182078.6A
Authority: CN
Inventors: 金在植; 张成根; 林锺吉
Original assignee: Chengdu Gaozhen Technology Co ltd
Current assignee: Chengdu Gaozhen Technology Co ltd
Priority date: 2021-10-11
Filing date: 2021-10-11
Publication date: 2023-04-14

Abstract

The invention discloses a method for improving the developing quality of a semiconductor, which comprises the following steps: starting the tilting mechanism to drive the semiconductor wafer bearing table to tilt at an angle; starting the rotating mechanism to drive the semiconductor wafer carrier to rotate; the spray head is controlled to spray the developing solution, so that the developing solution can be uniformly coated on the developing area. The invention ensures that the developing solution is uniformly distributed on the surface of the semiconductor when the developing solution is sprayed in the initial development stage by adding the inclination process in the developing process.

Description

Method for improving developing quality of semiconductor

Technical Field

The invention belongs to the technical field of semiconductor developing processes, and particularly relates to a method for improving the developing quality of a semiconductor.

Background

In the semiconductor manufacturing process, since the photoresist PR used in the exposure process is hydrophobic and the developer used in the initial stage of the development process is hydrophilic, the developer is unevenly distributed on the surface of the chip or wafer, and the excessive development is caused, thereby affecting the surface uniformity of the chip or wafer.

To solve this problem, the Pre-Wet process (Pre-Wet) is added in the early stage of the development (Develop) process, i.e. the development process early stage process includes two parts: DIW (deionized water) is sprayed in advance, then development (spraying of a developing solution) is carried out, and a carrier for bearing the semiconductor wafer is rotated while the developing solution is sprayed (namely, in a CW mode or a CCW mode), so that the developing solution is dispersed on the surface of the semiconductor wafer under the action of centrifugal force; however, the method has high requirement on the rotation speed to obtain a proper centrifugal force, as shown in fig. 1, the centrifugal force generated by clockwise rotation and counterclockwise rotation can only enable (1) and (2) of the developing area to uniformly apply the developing solution, while (3) of the developing area still cannot achieve uniform application of the developing solution, i.e. the problem of uniform development of the surface of the semiconductor wafer cannot be effectively improved by rotating the semiconductor wafer.

Then, the semiconductor wafer after the initial development treatment is immersed in the developer to perform main development, and in the main development stage, the semiconductor wafer is merely immersed in the developer to perform main development, which may cause residual scum in the development area, particularly at the edge of the development area, and may also affect the uniformity of the development area, thereby affecting the performance of the semiconductor wafer.

Disclosure of Invention

Therefore, in order to solve the problem that the performance of a semiconductor wafer is affected due to uneven development in the existing developing process, the invention provides a method for improving the developing quality of a semiconductor.

The invention is realized by the following technical scheme:

a method for improving the developing quality of a semiconductor comprises the following steps:

starting the tilting mechanism to drive the semiconductor wafer bearing table to tilt at an angle;

starting the rotating mechanism to drive the semiconductor wafer carrier to rotate;

the spray head is controlled to spray the developing solution, so that the developing solution can be uniformly coated on the developing area.

Preferably, the invention also needs to carry out a step of spraying deionized water before the step of controlling the spray head to spray the developing solution.

Preferably, the method of the present invention further comprises a main developing process:

controlling the rotating mechanism to stop the rotation of the semiconductor wafer bearing table;

controlling the semiconductor wafer bearing table to move so as to completely soak the semiconductor wafer in the developing solution;

and controlling the tilting mechanism to drive the semiconductor wafer bearing table to tilt left and right to generate vibration, so that residual residues in the developing area can fall off quickly.

Preferably, the present invention is inclined at an angle of not more than 30 °.

Preferably, the step of controlling the spray head to spray the developing solution further comprises:

the size or the inclination direction of the inclination angle of the semiconductor wafer bearing platform is adjusted by controlling the inclination mechanism.

the rotation speed or the rotation direction of the semiconductor wafer bearing table is adjusted by controlling the rotation mechanism.

Preferably, the main developing process of the present invention further includes:

the side-to-side oscillation frequency or the oscillation angle of the semiconductor wafer bearing table is adjusted by controlling the tilting mechanism.

Preferably, the tilting mechanism and the rotating mechanism of the present invention are each implemented by a driving motor.

Preferably, the method of the present invention implements the control of the tilting structure and the rotating structure by a controller or an upper computer.

The invention has the following advantages and beneficial effects:

the invention can ensure that the sprayed developing solution can be uniformly distributed on the surface of the semiconductor wafer when the developing solution is sprayed in the initial development stage by adding the inclination process in the developing process, thereby improving the uniformity of image development and ensuring the performance of the semiconductor.

In the final main developing process (i.e. soaking the semiconductor wafer in the developing solution), the semiconductor wafer is inclined to generate vibration, so that redundant residues in a developing area can be removed, the uniformity of the developing area is improved, and the performance of the semiconductor is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:

FIG. 1 is a schematic diagram of a conventional semiconductor wafer developing process.

FIG. 2 is a schematic view of the developing process of the present invention.

FIG. 3 is a schematic diagram of the development process of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.

Example 1

In a semiconductor manufacturing process, a pattern developing process is performed after an exposure process is performed on a wafer (wafer), because a photoresist PR coated on the wafer is a hydrophobic material in the exposure process, and a developing solution required to be used in the developing process is a hydrophilic material, the developing solution on the surface of the wafer cannot be uniformly coated. Therefore, in the prior art, a rapid Pre-wetting process (Pre-Wet) is added at the initial stage of development, i.e. deionized water is sprayed on a wafer to improve the hydrophobicity of a photoetching machine, then a developing solution is sprayed, and in the process, the wafer (CW/CCW) is rotated, so that the developing solution sprayed in the middle of the wafer can cover the whole wafer outwards under the action of centrifugal force; however, when only the rotation mode is adopted, as shown in fig. 1, when the CW mode is adopted, the developing solution state shown in the figure is formed in the developing area, that is, the uniformity of only the (1) part of the developing area in the figure can be ensured; with the CCW method, the developing solution state shown in the figure is formed in the developing area, that is, only the uniformity of the portion (2) of the developing area in the figure can be ensured, so that after CW + CCW is adopted, the phenomenon that the developing solution is not uniform in the portion (3) of the developing area still exists, that is, the above-mentioned prior art cannot effectively ensure that the developing solution is uniformly smeared in the developing area.

Therefore, in order to solve the above technical problems, the present embodiment provides a method for improving the quality of semiconductor development, which adds a tilt process in the development process, including adding a tilt function while the semiconductor wafer rotates at the initial development stage (Pre-Wet and development), so that the developer can be uniformly applied to the development area of the semiconductor wafer at the initial development stage; during main development, when the semiconductor wafer is soaked in the developing solution, the semiconductor wafer is inclined, and the generated vibration can quickly remove residues in a developing area of the semiconductor wafer, so that the developing quality is improved, and the performance of the semiconductor is further ensured.

Specifically, as shown in fig. 2, the method of this embodiment includes:

the initial development process:

starting the tilting mechanism to drive the wafer bearing table to tilt by a small angle; the inclination angle of the present embodiment is not more than 30 °.

Starting a rotating mechanism to drive the wafer bearing platform to rotate;

A main developing process:

controlling the rotating mechanism to stop the wafer bearing table from rotating;

controlling the wafer bearing platform to move so as to completely soak the semiconductor wafer borne on the wafer bearing platform in the developing solution;

the tilting mechanism is controlled to drive the wafer bearing platform to tilt left and right to generate vibration (swing), so that residual residues in the developing area fall off quickly, and the uniformity of the developing area is ensured.

The initial development process of this embodiment is shown in fig. 3, and it can be seen from fig. 3 that: the method of this embodiment overcomes the problem of partial non-uniformity of the developer solution in the development area only by centrifugal force (rotation) by adding a tilting force to the semiconductor wafer.

In the initial stage of development of this embodiment, before spraying the developing solution, spraying deionized water is further included.

In the process of spraying the developing solution, the inclination direction or the inclination angle of the semiconductor wafer carrier can be adjusted by controlling the inclination mechanism, for example, an upper left-to-lower right inclination mode, or a left-to-right inclination switching mode.

In the process of spraying the developing solution, the rotating speed or the rotating direction (CW, CCW, etc.) of the semiconductor wafer bearing platform can be adjusted by controlling the rotating mechanism, for example, in a clockwise rotating mode or a counterclockwise rotating mode.

In the main developing process, the frequency of the left-right swing of the semiconductor crystal bearing platform or the size of the swing angle can be adjusted by controlling the inclined structure.

The rotating mechanism and the inclined structure of the embodiment can be realized by adopting a motor and a transmission mechanism respectively; and a motor +2 sets of transmission structures can also be adopted to respectively convert the output rotating speed of the motor into corresponding rotary drive or linear drive.

The rotation and tilt control of this embodiment are controlled by a controller or an upper computer, and the control of rotation rate, acceleration, time, etc. can be realized, and the developing process control logic of this embodiment for a certain semiconductor wafer is shown in table 1:

TABLE 1

As can be seen from table 1, the developing process of this embodiment mainly includes: initial development and main development; wherein, the initial development stage comprises spraying deionized water DIW and spraying a developing solution; the semiconductor wafer is ensured to be inclined and rotated while the developing solution is sprayed, so that the developing solution can be uniformly coated on a developing area; after the initial development stage, main development is carried out, the semiconductor wafer is not rotated, the semiconductor wafer is soaked in the developing solution, and the semiconductor wafer is controlled to shake (incline) left and right, so that residual residues in a developing area of the semiconductor wafer fall off quickly, and the uniformity of development is ensured.

Of course, in another preferred embodiment, different control of the rotation speed, acceleration, time, etc. may be used for different semiconductor product requirements.

The above-mentioned embodiments, objects, technical solutions and advantages of the present invention are further described in detail, it should be understood that the above-mentioned embodiments are only examples of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. The method for improving the developing quality of the semiconductor is characterized by comprising the following steps:

2. The method as claimed in claim 1, wherein a step of spraying deionized water is further performed before the step of controlling the spray head to spray the developer.

3. The method of claim 1, further comprising a main development process:

4. A method of improving semiconductor development quality as claimed in claim 1 wherein the angle of inclination is no more than 30 °.

5. The method of claim 1, wherein the step of controlling the nozzle to spray the developer further comprises:

6. The method of claim 1, wherein the step of controlling the nozzle to spray the developer further comprises:

7. A method of improving semiconductor development quality as claimed in claim 3, wherein the main development process further comprises:

8. A method of upgrading semiconductor development according to any of claims 1-7, wherein the tilting and rotation mechanisms are each implemented by a drive motor.

9. A method for improving the quality of semiconductor development according to any of claims 1 to 7, wherein the method is implemented by a controller or a host computer for controlling the tilting mechanism and the rotating mechanism.