CN-122008066-A - Double-sided polishing method and equipment, computing equipment, medium and polished wafer

CN122008066ACN 122008066 ACN122008066 ACN 122008066ACN-122008066-A

Abstract

The present disclosure relates to a double-sided polishing method and apparatus, computing apparatus, medium, and polished wafer. In one aspect, the present disclosure provides a double-sided polishing method including rough polishing a wafer to be polished using a first polishing liquid, mixed polishing the rough polished wafer using a mixed polishing liquid formed by mixing the first polishing liquid and a second polishing liquid to which no alkaline substance is additionally added, first finishing polishing the mixed polished wafer using the second polishing liquid to which the alkaline substance is additionally added, and second finishing polishing the first finishing polished wafer using the second polishing liquid to which the alkaline substance is not additionally added. Therefore, the edge flatness of the wafer can be obviously improved while the surface quality of the whole wafer is ensured, so that the effective utilization area of the wafer and the chip yield are improved.

Inventors

PAN SHI
LIU HUANPING
BAI QIANGQIANG
WANG MING

Assignees

西安奕斯伟材料科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20251224

Claims (10)

1. A double-sided polishing method, comprising: Coarsely polishing a wafer to be polished by using a first polishing solution; performing mixed polishing on the wafer subjected to the rough polishing by using a mixed polishing solution formed by mixing the first polishing solution and a second polishing solution without an additional alkaline substance; Performing a first finish polishing on the wafer subjected to the mixed polishing using the second polishing liquid to which the alkaline substance is additionally added, and And performing second fine polishing on the wafer subjected to the first fine polishing by using the second polishing solution without adding the alkaline substance additionally.
2. The double-sided polishing method according to claim 1, wherein the first polishing liquid is a rough polishing liquid including abrasive particles, and the second polishing liquid is a fine polishing liquid including a polymer and abrasive particles.
3. The double-sided polishing method according to claim 1, wherein the alkaline substance comprises at least one of potassium hydroxide, ammonia water, and tetramethylammonium hydroxide.
4. The double-sided polishing method according to claim 1, wherein the alkaline substance is potassium hydroxide, and a volume ratio of the potassium hydroxide to the second polishing liquid is 1:750 to 1:1200.
5. The double-sided polishing method according to claim 1, wherein in the first finish polishing, the second polishing liquid is supplied through a first liquid supply line, the alkaline substance is supplied through a second liquid supply line, and the second polishing liquid and the alkaline substance are mixed at a liquid inlet end of a double-sided polishing apparatus.
6. The double-sided polishing method according to claim 1, wherein the material removal rate of the mixed polishing liquid is between the material removal rate of the first polishing liquid and the material removal rate of the second polishing liquid.
7. A double-sided polishing apparatus, comprising: The polishing disc is used for bearing a wafer to be polished and polishing the wafer, and is provided with a liquid inlet end; The first liquid supply system is communicated with the liquid inlet end so as to provide a first polishing liquid and a second polishing liquid for the wafer; a second liquid supply system in communication with the liquid inlet end for supplying alkaline substances to the wafer, and A controller that controls the first liquid supply system and the second liquid supply system to perform the double-sided polishing method according to any one of claims 1 to 6.
8. A computing device comprising a processor and a memory, the processor configured to execute instructions stored in the memory to implement the double-sided polishing method according to any one of claims 1-6.
9. A computer readable storage medium storing at least one instruction for execution by a processor to implement the double-sided polishing method according to any one of claims 1 to 6.
10. A polished wafer obtained by performing the double-sided polishing method according to any one of claims 1 to 6 on a wafer to be polished, the polished wafer having a surface roughness of <0.15nm, a local light scattering point of <8 having a size greater than 30nm after the cleaning and drying treatment, and having an ERO of-5 to 5mm at a point of 148mm from the center of the polished wafer in a radial direction on a surface of the polished wafer in a case where the diameter of the polished wafer is 300 mm.

Description

Double-sided polishing method and equipment, computing equipment, medium and polished wafer Technical Field The present disclosure relates to the field of semiconductor processing and manufacturing technology, and in particular, to a double-sided polishing method, a double-sided polishing apparatus, a computing apparatus, a computer readable storage medium, and a polished wafer. Background In the fabrication of semiconductor integrated circuits, wafers (wafer) are the most basic substrate material. The surface flatness of a wafer is one of the core indexes for determining success or failure of key processes such as subsequent photoetching and etching. In order to obtain a wafer surface with nano-scale flatness, chemical Mechanical Polishing (CMP) is an indispensable key process. In the related art, the double-sided polishing process generally employs step polishing, including a rough polishing stage and a finish polishing stage using polishing liquids of different properties, to gradually remove a damaged layer of a wafer surface, and finally achieve global planarization and mirror effects. However, how to further increase the flatness of the wafer, particularly the flatness of the edge area of the wafer, to increase the effective utilization area and yield of chip manufacturing is still a continuing concern and improvement in the art. Disclosure of Invention This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. According to an aspect of the present disclosure, a double-sided polishing method is provided. The double-sided polishing method comprises the steps of roughly polishing a wafer to be polished by using a first polishing solution, carrying out mixed polishing on the wafer subjected to rough polishing by using a mixed polishing solution formed by mixing the first polishing solution and a second polishing solution without adding an alkaline substance, carrying out first fine polishing on the wafer subjected to mixed polishing by using the second polishing solution with the alkaline substance added, and carrying out second fine polishing on the wafer subjected to the first fine polishing by using the second polishing solution without adding the alkaline substance. In some embodiments, the first polishing liquid is a coarse polishing liquid comprising abrasive particles and the second polishing liquid is a fine polishing liquid comprising a polymer and abrasive particles. In some embodiments, the alkaline substance may include at least one of potassium hydroxide, ammonia, and tetramethylammonium hydroxide. In some embodiments, the alkaline substance may be potassium hydroxide, and the volume ratio of the potassium hydroxide to the second polishing solution is 1:750-1:1200. In some embodiments, in the first polishing, the second polishing liquid may be supplied through a first liquid supply line, the alkaline substance may be supplied through a second liquid supply line, and the second polishing liquid and the alkaline substance may be mixed at a liquid inlet end of the double-sided polishing apparatus. In some embodiments, the mixed slurry has a material removal rate that is between the material removal rate of the first slurry and the material removal rate of the second slurry. According to another aspect of the present disclosure, there is also provided a double-sided polishing apparatus. The double-sided polishing device comprises a polishing disc, a first liquid supply system, a second liquid supply system and a controller. The polishing disk is used for bearing a wafer to be polished and polishing the wafer, and is provided with a liquid inlet end. The first liquid supply system is communicated with the liquid inlet end so as to provide a first polishing liquid and a second polishing liquid for the wafer. The second liquid supply system is communicated with the liquid inlet end so as to provide alkaline substances for the wafer. The controller controls the first liquid supply system and the second liquid supply system to perform the double-sided polishing method of any one of the above embodiments. According to yet another aspect of the present disclosure, a computing device is also provided. The computing device includes a processor and a memory. The processor is configured to execute instructions stored in the memory to implement the double-sided polishing method according to any of the above embodiments. According to yet another aspect of the present disclosure, a computer-readable storage medium is also provided. The computer readable storage medium stores at least one instruction for execution by a processor to implement the double-sided polishing method of any of the embodiments described above. According to yet another aspect of the present disclosure, there is also provided a polished wafer. The polished wafer is obtained by performing the double-sided polishing method of any one of the above embodiments on