Patent Application
20240286244
The present invention relates to an electrostatic suction cup device for wafer chemical mechanical polishing, in particular to a device that can stably absorb wafers regardless of their thickness, in order to improve the yield and process, achieve a better thinning effect, and remove the need for the pre-process of applying adhesive and film to enhance wafer strength, as well as the post-process of removing adhesive and film, reducing the associated time, cost, and risk of wafer fragmentation. Furthermore, it saves the time and cost of frequent maintenance required by the conventional vacuum suction method, and the innovative design of the electrostatic suction cup device for wafer chemical mechanical polishing has enhanced its practical effectiveness and characteristics in its overall implementation and use.
In recent years, the semiconductor industry has developed rapidly, and the application of various semiconductor chips is extensive. The research, development, and production of semiconductor chips often affect many industries globally. Wafer is the abbreviation for semiconductor crystal round wafer, which is a thin slice of a cylindrical semiconductor crystal that is used as a carrier substrate in the integrated circuit manufacturing process and in the manufacture of solar cells. Because of its circular shape, it is called a wafer. The most common ones are silicon wafers, but there are also gallium nitride wafers, silicon carbide wafers, etc.
In each process of the wafer, if there are defects such as uneven surface smoothness and unevenness, it will affect the yield and efficiency of the final product, so chemical etching and mechanical processing will be used in the microcircuit formed by repeated exposure, development and etching. Chemical-Mechanical Polishing (CMP) is a process in which a slurry is used to thin or polish the wafer, reducing or removing the height differences caused by repeated stacking processes and reducing the thickness of the wafer substrate or film material in the process. In addition to controlling the thickness of the wafer in the Chemical-Mechanical Polishing (CMP) process, the final surface polishing of the wafer is also a Chemical-Mechanical Polishing (CMP) procedure, removing the residue on the wafer surface after reaching the target thickness (mirror finishing) to prepare for the next semiconductor process.
In the Chemical-Mechanical Polishing (CMP) process of wafers, the suction cup of the wafer carrier is mainly used to suck up the wafer and transfer it to the corresponding polishing pad, and at the same time rotate the suction cup of the wafer carrier and polishing pad to polish the wafer. However, the suction cup is generally a vacuum suction cup, and although the vacuum suction cup can achieve the expected effect of sucking the wafer, in the process of its actual operation, it is also found that due to the progress of science and technology and the rapid change of technology, the diameter of the wafer is getting larger and the thickness is getting thinner. As a result, when the vacuum suction cup suctions a wafer with a large diameter and a thin thickness, due to insufficient stress on the wafer, the wafer is easily damaged by the suction force of the vacuum suction cup. Although, the industry will coat an adhesive layer on the surface of the wafer to use the adhesive layer to increase the stress of the wafer, during the process of removing the adhesive layer from the wafer after polishing, it is also easy to cause damage to the wafer, resulting in a limit on the thickness of the wafer that the vacuum suction cup can pick up.
In addition, some companies have developed the use of a ceramic suction cup to suck the wafer and transfer it to the polishing pad for polishing operations, but the ceramic suction cup allows the vacuum suction force to suck the wafer through the micropores on the surface of the ceramic suction cup, and the fine particles contained in the slurry used in the polishing process of the wafer are easy to block the micropores on the surface of the ceramic suction cup, resulting in the need to clean the ceramic suction cup from time to time in order to maintain sufficient suction power of the ceramic suction cup, making the ceramic suction cup extremely inconvenient in the overall operation and use.
Therefore, the inventor, based on years of rich design and development experience in the industry, has studied and improved the conventional technical means and provided an electrostatic suction cup device for wafer chemical mechanical polishing, aiming to achieve better practical value.
The main object of the present invention is to provide an electrostatic suction cup device for wafer chemical mechanical polishing, which mainly uses an electrostatic suction cup to absorb wafer for Chemical-Mechanical Polishing (CMP) operations, so that wafer can be steadily absorbed without being affected by wafer thickness, so as to improve yield and process improvement, achieve a better thinning effect, and remove the time and cost of gluing and film application corresponding to strengthening the strength of wafers before the wafer process. It can also avoid the procedures, costs and risk of fragmentation of degumming and film removal after the process, saving the time and cost of frequent maintenance required by the current vacuum suction method and adding practical and functional features to its overall implementation.
The main purpose and effect of the electrostatic suction cup device for wafer chemical mechanical polishing of the present invention are achieved by the following specific technical means,
According to a preferred embodiment of the electrostatic suction cup device for wafer chemical mechanical polishing of the present invention, the wafer carrier has a quick-release unit provided at a bottom thereof for combination with a machine.
In order to have a more complete and clear disclosure of the technical content used in the present invention, the purpose of the invention, and the effect achieved, the present invention is described in detail below, referring to the disclosed drawings and drawing numbers.
First, referring to
In this way, during operation and use of the present invention, the control module (21) can control the electrostatic suction cup (2) to generate static electricity so that the wafer (3) is attracted by the electrostatic attraction of the electrostatic suction cup (2) and adsorbed on the suction surface (11) of the wafer carrier (1). Then, the wafer carrier (1) is moved to the corresponding polishing pad (4) through the machine, referring to
In addition, referring to the view of the use state of the quick-release unit of the present invention in
From the above, the description of the use and embodiment of the present invention shows that compared with the prior art means, advantages and effects provided by the present invention include the following:
Additional changes and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, aforementioned embodiments or views shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalent.
| Number | Date | Country | Kind |
|---|---|---|---|
| 112201676 | Feb 2023 | TW | national |
