CN111063639A

CN111063639A - Mechanical device for improving cleaning capability of high-density bump structure and cleaning method thereof

Info

Publication number: CN111063639A
Application number: CN201911355268.6A
Authority: CN
Inventors: 李恒甫; 姚大平; 曹立强
Original assignee: National Center for Advanced Packaging Co Ltd; Shanghai Xianfang Semiconductor Co Ltd
Current assignee: National Center for Advanced Packaging Co Ltd; Shanghai Xianfang Semiconductor Co Ltd
Priority date: 2019-12-25
Filing date: 2019-12-25
Publication date: 2020-04-24

Abstract

The invention discloses a cleaning device for a high-density bump structure, which comprises: the carrying platform is used for placing a wafer to be operated; the variable-direction nozzle structure is positioned above the carrier platform and used for conveying chemical liquid to the surface of the wafer, the variable-direction nozzle structure comprises a chemical conveying pipeline, a direction changing device and a chemical output end pipeline, the conveying pipeline, the direction changing device and the chemical output end pipeline are in liquid communication, and the output end pipeline changes the output direction of the chemical through the direction changing device.

Description

Mechanical device for improving cleaning capability of high-density bump structure and cleaning method thereof

Technical Field

The invention relates to the technical field of semiconductor manufacturing and processes. Specifically, the invention relates to a mechanical device for improving the cleaning capability of a high-density bump structure and a cleaning method thereof.

Background

Along with the development of miniaturization, integration and intellectualization of electronic products, the complexity of an IC chip is greatly increased, and the number of corresponding IO pins is also greatly improved. With the development of the integrated circuit technology, the size of a device is smaller and smaller, the integration level is high, the graphic structure is developed towards the direction of high density and fine pitch, and photoresist removal and metal seed layer corrosion are important processes in a rewiring process in the manufacturing process of a packaging technology. However, in the high-density fine pitch bump structure, due to the large aspect ratio, it is difficult for the conventional cleaning method to effectively remove the material, such as the photoresist or the metal seed layer, at the bottom or bottom sidewall of the pattern, and therefore the photoresist or seed layer at the bottom or bottom sidewall of the bump is difficult to be removed completely, resulting in product defects.

In the existing cleaning device, chemical liquid for cleaning flows downwards to the surface of the wafer through the nozzle, but the cleaning effect is general, the cleaning time is long, and the cost is high. To achieve better cleaning, there is a need in the art for a mechanical device that enhances the cleaning capabilities of high-density bump structures.

Disclosure of Invention

In view of the problems in the prior art, according to one aspect of the present invention, there is provided a cleaning apparatus for a high-density bump structure, including:

the carrying platform is used for placing a wafer to be operated;

the variable-direction nozzle structure is positioned above the carrier platform and used for conveying chemical liquid to the surface of the wafer, the variable-direction nozzle structure comprises a chemical conveying pipeline, a direction changing device and a chemical output end pipeline, the conveying pipeline, the direction changing device and the chemical output end pipeline are in liquid communication, and the output end pipeline changes the output direction of the chemical through the direction changing device.

In one embodiment of the present invention, the carrier drives the wafer to rotate around the center.

In one embodiment of the invention, the variable direction nozzle structure rotates around a fixed shaft in the cavity, and the rotation range is set in a program.

In one embodiment of the invention, the direction changing device is connected with a process menu control system through signals so as to control the output direction of the chemicals in a menu program

According to another embodiment of the present invention, there is provided a method for cleaning a wafer using a cleaning apparatus for high-density bump structures, wherein the wafer includes an array of bump structures and a substance to be cleaned between the bump structures, the method including:

placing a wafer on the stage;

delivering chemicals from the output end pipeline to the surface of the wafer in a first direction;

and delivering the chemicals from the output pipeline to the surface of the wafer in a second direction, wherein the second direction is different from the first direction.

The invention has the advantages that: through changing the fixed nozzle of chemicals and changing to have vector nature structure nozzle, can make chemical liquid direction of delivery become the variable direction type by the fixed type, so, can direct action in lug bottom lateral wall position department through the output direction that changes the chemicals, the corruption or the ability of removing glue that this kind of device can effectively promote chemical liquid.

Drawings

To further clarify the above and other advantages and features of embodiments of the present invention, a more particular description of embodiments of the invention will be rendered by reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. In the drawings, the same or corresponding parts will be denoted by the same or similar reference numerals for clarity.

Fig. 1 shows a schematic cross-sectional view of a cleaning apparatus 100 for high-density bump structures.

Fig. 2 shows a schematic cross-sectional view of a cleaning apparatus 200 for a high-density bump structure according to an embodiment of the invention.

Figure 3 shows a schematic cross-sectional view of a wafer 300 to be processed according to one embodiment of the invention.

Fig. 4 is a cross-sectional view of the photoresist remaining at the bottom of the bump structure of the wafer 400 to be processed according to an embodiment of the invention.

Fig. 5 is a cross-sectional view illustrating a photoresist remaining at the bottom of a bump structure of a wafer 500 to be processed according to an embodiment of the invention.

The graphic sizes in the figures are not shown to represent actual sizes, but are shown for clarity. The graphic sizes in the figures are not shown to represent actual sizes, but are shown for clarity. Spatial terms such as "front," "back," "over," "under," and the like may be used herein to describe one element or feature's relationship to another element or feature as illustrated. Spatially relative terms may encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. In addition, the device may be oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Detailed Description

In the following description, the invention is described with reference to various embodiments. One skilled in the relevant art will recognize, however, that the embodiments may be practiced without one or more of the specific details, or with other alternative and/or additional methods, materials, or components. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of embodiments of the invention. Similarly, for purposes of explanation, specific numbers, materials and configurations are set forth in order to provide a thorough understanding of the embodiments of the invention. However, the invention may be practiced without specific details. Further, it should be understood that the embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.

Reference in the specification to "one embodiment" or "the embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.

Fig. 1 shows a schematic cross-sectional view of a cleaning apparatus 100 for high-density bump structures. As shown in fig. 1, the cleaning apparatus 100 includes a stage 110 and a nozzle structure 120. The carrier 110 is used for placing a wafer 130 to be processed and can drive the wafer 130 to rotate around a center, as shown by an arrow 150. The nozzle structure 120 is used to deliver chemical liquid to the surface of the wafer 130, and the nozzle structure 120 rotates around the shaft 140 in the chamber, and the rotation range can be set within a program so as to obtain better uniformity. However, in the apparatus 100, the nozzle structure 120 is fixed by the shaft 130, and the chemical liquid flows downward toward the surface of the wafer 110 through the nozzle structure 120, so that the chemical liquid is always transported in a fixed vertical downward direction.

In order to realize better cleaning effect, can change the fixed nozzle of chemicals into having vector nature structure nozzle, can make chemical liquid direction of delivery become the variable direction type by the fixed type, so, can direct action in protruding bottom lateral wall position department of wafer high density through the output direction who changes the chemicals, this kind of device can effectively promote the corruption or the ability of removing glue.

Fig. 2 shows a schematic cross-sectional view of a cleaning apparatus 200 for a high-density bump structure according to an embodiment of the invention. As shown in fig. 2, the cleaning apparatus 200 includes a stage 210 and a variable direction nozzle structure 220. The carrier 210 is used for placing a wafer 230 to be processed and can drive the wafer 230 to rotate around the center, as shown by an arrow 250. The nozzle structure 220 is used to deliver chemical liquid to the surface of the wafer 230, and the nozzle structure 220 rotates around the shaft 240 in the chamber, and the rotation range can be set within a program so as to obtain better uniformity. The nozzle structure 220 is a triple connection nozzle structure including a chemical delivery pipe 221, a direction changing device 222, and a chemical output pipe 223. The delivery line 221, direction change device 222, and chemical outlet line 223 are in fluid communication. The direction changing device 222 is connected to the process recipe control system by a signal so that the output direction of the chemical liquid can be controlled in the recipe program. The chemical delivery line 221 rotates the nozzle structure 220 within the chamber about the axis 240, and the rotation range can be set within the program, so as to have better uniformity. Since the outlet pipe 223 of the nozzle structure can be changed in direction by the direction changing device 222, the outflow direction of the chemical relative to the wafer surface can be changed, so that the liquid reaching the bottom of the dense fine pitch structure can be enhanced, and the photoresist removing or etching capability can be improved.

Figure 3 shows a schematic cross-sectional view of a wafer 300 to be processed according to one embodiment of the invention. The surface of the wafer 300 to be processed has high-density fine-pitch bump structures 310 and photoresist 330 between the bump structures 310. To remove the photoresist 330, the deglued liquid 320 is delivered from the nozzle structure line to the wafer surface. Under the condition of a fixed cleaning device, after the electroplating process of packaging and manufacturing the high-density bump is finished, a photoresist removing process is required. Taking the single wafer type photoresist stripping process as an example, the photoresist solution 320 is delivered to the surface of the wafer 300 through a nozzle during the photoresist stripping process, and reacts with the photoresist 330 in the wafer structure to be dissolved and removed. However, during the photoresist stripping process, the photoresist stripping solution 320 is difficult to enter the bottom of the bump structure 310, and thus photoresist residue is easily caused.

Fig. 4 is a cross-sectional view of the photoresist remaining at the bottom of the bump structure of the wafer 400 to be processed according to an embodiment of the invention. As shown in fig. 4, the surface of the wafer 400 to be processed has a high-density fine-pitch bump structure 410, and the photoresist 420 remains at the bottom of the bump structure 410.

The photoresist remaining at the bottom may be removed by the cleaning apparatus 200 for a high density bump structure according to an embodiment of the present invention. As shown in fig. 5, the surface of the wafer 500 to be processed has a high-density fine-pitch bump structure 510, and the photoresist 520 remains on the bottom of the bump structure 510. The photoresist stripper 530 after changing the transport direction is directly applied to the bottom residual photoresist 520 from different directions. Under the condition of the variable direction nozzle device, the chemical liquid conveying direction can be changed, so that the chemical liquid can be directly applied to the bottom side area of the high-density structure, and the substance residue at the bottom side of the fine-pitch structure can be effectively removed.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various combinations, modifications, and changes can be made thereto without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention disclosed herein should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

Claims

1. A cleaning apparatus for a high-density bump structure, comprising:

the carrying platform is used for placing a wafer to be operated;

2. The apparatus according to claim 1, wherein the carrier rotates the wafer about the center.

3. The apparatus for cleaning high density bump structures of claim 1 wherein the variable direction nozzle structure rotates about a fixed axis within the chamber, the range of rotation being programmed.

4. The apparatus for cleaning a high-density bump structure as recited in claim 1, wherein the direction changing device is connected to the process recipe control system by a signal to control the direction of the chemical output in the recipe program.

5. A method for cleaning a wafer using the cleaning apparatus for high-density bump structures according to any one of claims 1 to 4, wherein the wafer comprises an array of bump structures and a substance to be cleaned between the bump structures, the method comprising:

placing a wafer on the stage;