CN-122018235-A - Glue spreading method for leveling photoresist surface by utilizing airflow and liquid medicine steam

Abstract

The invention relates to a glue spreading method for leveling the surface of photoresist by utilizing air flow and liquid medicine steam, which realizes temporary storage of the liquid medicine in a collecting cup and forms a constant humidity state in a cavity by arranging a liquid level guide port with an opening height higher than the bottom surface of the collecting cup, then brings moisture formed by the liquid medicine in the cavity to the surface of a wafer by the air flow generated by rotation of the wafer, slightly dissolves the surface of the photoresist of the wafer by utilizing the liquid medicine steam, and enables the surface of the photoresist to realize a leveling effect, thereby enabling the surface of the photoresist to be smoother and meeting the requirements of the subsequent process.

Inventors

• HE SIYUAN

Assignees

• 沈阳芯源微电子设备股份有限公司

Dates

Publication Date

20260512

Application Date

20241112

Claims (5)

1. 1. The photoresist surface leveling gluing method by utilizing air flow and liquid medicine steam is characterized by comprising a wafer bearing table (2), wherein a collecting cup (3) is arranged on the outer side of the wafer bearing table (2), a liquid level guiding opening (5) with an opening height higher than the bottom surface of the collecting cup (3) is arranged in the collecting cup (3), and the photoresist surface leveling gluing method comprises the following steps: Placing a wafer (1) on a wafer bearing table (2); Step two, the glue spraying swing arm moves to the upper side of the wafer (1) and sprays glue on the wafer (1), and meanwhile, the wafer (1) is driven to rotate at a set rotating speed through the wafer bearing table (2); step three, a wafer bearing table (2) drives a wafer (1) to rotate at a back washing rotating speed and enables photoresist on the surface to be spread, and a back spraying device on the lower side of the wafer (1) is started to spray back washing liquid onto the back of the wafer (1); and fourthly, the wafer bearing table (2) drives the wafer (1) to rotate at a leveling rotating speed, and the liquid medicine in the collecting cup (3) forms liquid medicine steam and is carried to the surface of the photoresist through air flow formed by the rotation of the wafer (1) to realize photoresist erosion leveling.
2. 2. The method for coating photoresist surface leveling by using air flow and chemical vapor according to claim 1, wherein in the third step, the back-coating liquid is sprayed to the back-coating liquid outermost position (6) of the wafer (1) which is previously drawn.
3. 3. The method of claim 1, wherein in the third step, the back washing speed is V1, the back washing time is T1, in the fourth step, the leveling speed is V2, and V2=V1, the leveling time is T2, and T2 is greater than T1.
4. 4. The method for coating photoresist surface leveling by using air flow and chemical vapor as set forth in claim 1, wherein the liquid level guiding opening (5) is a height-adjustable structure.
5. 5. The photoresist surface leveling glue spreading method by utilizing air flow and liquid medicine steam according to claim 4, wherein a liquid discharge pipe (4) is arranged on the lower side of the collecting cup (3), and the lower end of the liquid level guiding port (5) is inserted into the liquid discharge pipe (4) in a threaded manner.

Description

Glue spreading method for leveling photoresist surface by utilizing airflow and liquid medicine steam Technical Field The invention relates to the technical field of semiconductors, in particular to a glue coating method for leveling the surface of photoresist by utilizing airflow and liquid medicine steam. Background In the prior art, although the surface of the photoresist after spreading is relatively flat by controlling the air flow strength of the wafer during movement, the influence of the air flow on the surface of the photoresist cannot be completely avoided, and as the software flow field simulation finds that the surface of the wafer only needs to move, the air flow with certain strength can be formed on the surface of the photoresist during spreading and etching, so that the surface of the photoresist is always uneven, and the subsequent manufacturing process is influenced. The patent with the publication number of CN112748639B discloses an FFU rectifying plate with air flow partition regulation and glue coating process for adjusting glue shape, which changes the air flow environment of a glue coating cavity by designing the FFU rectifying plate with a specific structure, thereby realizing the partition regulation of the air flow for regulating the glue coating film thickness at the center and the edge of a wafer, but the process is mainly used for improving the problem of multi-cavity glue coating consistency. In addition, the collecting cup for collecting the waste liquid by the spin coater unit in the prior art cannot store the liquid medicine temporarily, for example, patent publication number CN107608180B discloses a waste discharge system of a plurality of spin coater units, and the waste liquid in the collecting cup is directly discharged into the liquid collecting box through the liquid outlet at the lower side of the collecting cup. Disclosure of Invention The invention aims to provide a glue coating method for leveling the surface of photoresist by utilizing air flow and liquid medicine steam, which realizes temporary storage of liquid medicine in a collecting cup and forms a constant humidity state in a cavity to a certain extent by arranging a liquid level guide port with an opening height higher than the bottom surface of the collecting cup, brings moisture formed by the liquid medicine in the cavity to the surface of a wafer by utilizing the air flow generated by rotation of a wafer, slightly dissolves the surface of the photoresist of the wafer by utilizing the liquid medicine steam, and realizes the leveling effect on the surface of the photoresist, so that the surface of the photoresist is smoother, and the requirement of a subsequent process can be met. The aim of the invention is realized by the following technical scheme: the photoresist surface leveling gluing method by utilizing air flow and liquid medicine steam comprises a wafer bearing table, wherein a collecting cup is arranged on the outer side of the wafer bearing table, a liquid level guiding opening with an opening height higher than the bottom surface of the collecting cup is arranged in the collecting cup, and the photoresist surface leveling gluing method comprises the following steps: Placing a wafer on a wafer bearing table; step two, the glue spraying swing arm moves to the upper side of the wafer and sprays glue on the wafer, and meanwhile the wafer is driven to rotate at a set rotating speed through the wafer bearing table; step three, the wafer bearing table drives the wafer to rotate at a back washing rotating speed and spreads out photoresist on the surface, and simultaneously a back spraying device on the lower side of the wafer is started to spray back washing liquid on the back surface of the wafer; And fourthly, the wafer bearing table drives the wafer to rotate at a leveling rotating speed, and the liquid medicine in the collecting cup forms liquid medicine steam and is brought to the surface of the photoresist through air flow formed by the rotation of the wafer to realize photoresist corrosion leveling. And thirdly, spraying back washing liquid to the outermost position of the back washing liquid drawn in advance on the back of the wafer. In the third step, the back washing rotating speed is V1, the back washing time is T1, in the fourth step, the leveling rotating speed is V2, v2=v1, the leveling time is T2, and T2 is greater than T1. The liquid level guiding opening is of a height-adjustable structure. The lower side of the collecting cup is provided with a liquid discharge pipe, and the lower end of the liquid level guiding port is inserted into the liquid discharge pipe through threads. The invention has the advantages and positive effects that: 1. According to the invention, the liquid medicine is temporarily stored in the collecting cup and forms a constant humidity state in the cavity to a certain extent by arranging the liquid level guide port with the opening height higher than the bottom s