阅读说明：本技术 抛光介质制备装置和方法、机械化学抛光设备和方法 (Polishing medium preparation device and method, and mechanical chemical polishing equipment and method ) 是由 尹涛 赵盼盼 尹永仁 冯凯萍 张天雷 于 2020-06-15 设计创作，主要内容包括：本发明涉及抛光领域,公开了一种抛光介质制备装置和方法、机械化学抛光设备和方法。其中,所述一种抛光介质制备装置包括用于储存抛光液的储液罐、用于向所述储液罐内释放预定压力气体的气压泵、第一管道和第二管道；所述第一管道的一端与所述气压泵的出气口连接,另一端从所述储液罐的进液口延伸至所述储液罐的底部；所述第二管道从所述储液罐的底部延伸至所述储液罐外；所述第一管道延伸至所述储液罐的底部的一端设置有螺旋增压结构,所述螺旋增压结构用于促进从所述第一管道释放的气体与所述储液罐内的抛光液充分混合,以形成抛光介质。通过上述技术上方案,能够制备满足高效率抛光和高品质抛光的抛光介质。(The invention relates to the field of polishing, and discloses a polishing medium preparation device and method, and mechanochemical polishing equipment and method. The polishing medium preparation device comprises a liquid storage tank for storing polishing liquid, a pneumatic pump for releasing gas with preset pressure into the liquid storage tank, a first pipeline and a second pipeline; one end of the first pipeline is connected with an air outlet of the pneumatic pump, and the other end of the first pipeline extends to the bottom of the liquid storage tank from a liquid inlet of the liquid storage tank; the second pipeline extends from the bottom of the liquid storage tank to the outside of the liquid storage tank; one end of the first pipeline, which extends to the bottom of the liquid storage tank, is provided with a spiral pressurization structure, and the spiral pressurization structure is used for promoting the gas released from the first pipeline to be fully mixed with the polishing liquid in the liquid storage tank so as to form a polishing medium. Through the technical scheme, the polishing medium meeting the requirements of high-efficiency polishing and high-quality polishing can be prepared.)

1. A polishing medium preparation device is characterized by comprising a liquid storage tank (1) for storing polishing liquid, a pneumatic pump (2) for releasing gas with preset pressure into the liquid storage tank (1), a first pipeline (3) and a second pipeline (4); one end of the first pipeline (3) is connected with an air outlet of the pneumatic pump (2), and the other end of the first pipeline extends to the bottom of the liquid storage tank (1) from a liquid inlet of the liquid storage tank (1); the second pipeline (4) extends from the bottom of the liquid storage tank (1) to the outside of the liquid storage tank (1); one end of the first pipeline (3) extending to the bottom of the liquid storage tank (1) is provided with a spiral pressurization structure (5), and the spiral pressurization structure (5) is used for promoting the gas released from the first pipeline (3) to be fully mixed with the polishing liquid in the liquid storage tank (1) so as to form a polishing medium.

2. The polishing medium preparation apparatus according to claim 1, wherein the polishing liquid preparation apparatus further comprises a third pipe (6) and a gas tank (7), one end of the third pipe (6) is connected to a gas inlet of the pneumatic pump (2), and the other end is connected to a gas outlet of the gas tank (7).

3. A polishing medium preparation device according to claim 1, characterized in that a valve (8) for controlling the flow of fluid in the second conduit (4) is provided on the second conduit (4).

4. The polishing medium preparation apparatus according to claim 1, wherein the screw pressurizing structure (5) comprises a body (51) and a through hole (52) provided on a side wall of the body (51), a screw passage (53) is provided in the body (51) along an axial direction of the body (51), and the through hole (52) communicates with the screw passage (53); the spiral channel (53) satisfies at least one of the following conditions:

(a) the pitch of the spiral channel (53) is decreased progressively along the axial direction of the body (51);

(b) the cross-sectional diameter of the spiral channel (53) is decreased progressively along the axial direction of the body (51);

(c) the diameter of the spiral channel (53) decreases in the axial direction of the body (51).

5. The polishing medium preparation device according to claim 1, wherein the spiral pressurizing structure (5) comprises a body (51) and a through hole (52) arranged on a side wall of the body (51), a spiral channel (53) distributed along the axial direction of the body (51) is arranged on the inner wall of the body (51), a central column (54) is arranged in the body (51) along the axial direction of the body (51), and a certain gap is arranged between the side wall of the central column (54) and the side wall of the spiral channel (53) or the side wall of the central column (54); the through hole (52) communicates with the threaded passage (53);

the spiral channel (53) satisfies at least one of the following conditions:

(a) the pitch of the spiral channel (53) is decreased progressively along the axial direction of the body (51);

(b) the cross-sectional diameter of the spiral channel (53) is decreased progressively along the axial direction of the body (51);

(c) the diameter of the spiral channel (53) decreases in the axial direction of the body (51).

6. A polishing medium production method characterized by carrying out production of a polishing medium by using the polishing medium production apparatus of any one of claims 1 to 5, the polishing medium production method comprising: at least one gas of hydrogen, helium, nitrogen, oxygen, fluorine, neon, chlorine, argon, ozone, ammonia, carbon dioxide and nitrogen dioxide is stored in the gas storage tank (7); storing polishing solution in the liquid storage tank (1); and releasing gas with preset pressure into the liquid storage tank (1) by using the pneumatic pump (2), and promoting the gas to be fully mixed with polishing liquid by using the spiral pressurization structure (5) so as to obtain a polishing medium.

7. The method for preparing a polishing medium according to claim 6, wherein: the pressure of the gas released from the gas storage tank (7) is increased to 0-500kPa by using the pneumatic pump, and then the gas is released into the liquid storage tank (1);

storing oxygen, nitrogen, argon and air in the gas storage tank (7);

or the like, or, alternatively,

storing oxygen in the gas storage tank (7);

or the like, or, alternatively,

storing air in the air storage tank (7);

or the like, or, alternatively,

and storing oxygen and nitrogen in the gas storage tank (7).

8. The method for preparing a polishing medium according to claim 7, wherein:

adding polishing particles into the polishing solution, wherein the polishing particles are at least one of diamond, cubic boron nitride, boron carbide, silicon carbide, aluminum oxide, cerium oxide, silicon oxide, titanium oxide, zirconium oxide and manganese oxide; the polishing particles account for 5-30 wt% of the polishing solution; the grain diameter of the polishing particles is 0.05-1 mu m;

adding a chemical additive into the polishing solution, wherein the chemical additive is at least one of acid, alkali, salt metal oxide and non-metal oxide, and the chemical additive accounts for 0-10 wt% of the polishing solution.

9. A mechanochemical polishing device comprising a mechanochemical processing chamber and a polishing medium preparation means according to any one of claims 1 to 5;

the mechanochemical processing chamber also comprises a bracket (9), a polishing disk (10) arranged on the bracket (9), a motor (11) which is arranged below the polishing disk (10) and used for driving the polishing disk (10) to rotate, a polishing pad (12) adhered to the upper surface of the polishing disk (10), a pressure weight (13) positioned above the polishing disk (10) and a driving mechanism used for driving the pressure weight (13) to rotate; the polishing medium is capable of flowing through a second conduit (4) to the upper surface of the polishing pad (12).

10. A mechanochemical polishing method characterized by subjecting a semiconductor material to mechanochemical polishing using the mechanochemical polishing apparatus as set forth in claim 9;

attaching a semiconductor material to be polished to the lower end face of the pressure weight (13), conveying the polishing medium onto the polishing pad (12), driving the polishing disc (10) to rotate by the motor (11), and driving the pressure weight (13) to rotate on the upper surface of the polishing pad by the driving mechanism.

Technical Field

The invention relates to the technical field of polishing, in particular to a polishing medium preparation device and method, and mechanochemical polishing equipment and method.

Background

With the continuous deepening of the automation and intellectualization process of industrial products, the application market of semiconductor chips in the top field and the civil field grows rapidly. According to statistics, more than 2000 billion dollars of chips are imported every year in China, and more than petroleum is the first major import product. However, although China has a relatively perfect semiconductor industry chain, the manufacturing capability can only meet the production of low-density transistor chips, and the requirement has a huge gap because of the fact that the manufacturing capability cannot be self-sufficient in the advanced scientific and technological fields of new energy automobiles, high-power electric appliances, 5G communication networks, aerospace and the like. High-end electronic chips rely heavily on importation, mainly because of the inability of manufacturing capabilities to meet design requirements. Therefore, there is a need for the construction of the semiconductor industry chain and the autonomous breakthrough of critical processes.

With the demands for miniaturization of chip wiring, 3D multilayer wiring, and epitaxial layer growth, it is necessary for the surface of the semiconductor substrate to have a TTV <1um, Ra <0.3nm, no scratch, no damage layer, and the like, and extremely strict requirements are imposed. To meet the above requirements, the mechanochemical polishing process, which is the front end of the semiconductor manufacturing process, becomes a crucial step from the material to the chip of the semiconductor. Since the mechanical chemical polishing requires that scratches, surface damages, etc. generated on the surface of the semiconductor substrate in the previous processes, such as cutting, grinding, and pinning, must be completely removed and new damages cannot be generated, the requirements on the polishing solution, the polishing pad, and the polishing equipment used in polishing are very strict, which results in very high precision and quality of the semiconductor surface substrate after processing, but the processing efficiency is very low. This makes mechanochemical polishing the most expensive consumable material in the front-end engineering of semiconductors. Therefore, there is an urgent need for a polishing apparatus and method that can ensure high quality of the surface of a semiconductor substrate and have high efficiency.

Disclosure of Invention

Aiming at the defects of the existing semiconductor material mechanical chemical polishing technology, the invention provides a polishing medium preparation device and method, and mechanical chemical polishing equipment and method, so as to realize the high-efficiency and high-quality mechanical chemical polishing of semiconductor materials.

In order to achieve the above object, a first aspect of the present invention provides a polishing medium preparation apparatus including a liquid reservoir for storing a polishing liquid, a pneumatic pump for releasing a gas of a predetermined pressure into the liquid reservoir, a first pipe, and a second pipe; one end of the first pipeline is connected with an air outlet of the pneumatic pump, and the other end of the first pipeline extends to the bottom of the liquid storage tank from a liquid inlet of the liquid storage tank; the second pipeline extends from the bottom of the liquid storage tank to the outside of the liquid storage tank; one end of the first pipeline, which extends to the bottom of the liquid storage tank, is provided with a spiral pressurization structure, and the spiral pressurization structure is used for promoting the gas released from the first pipeline to be fully mixed with the polishing liquid in the liquid storage tank so as to form a polishing medium.

Reaction gas is pressurized by the pneumatic pump and then injected into the liquid storage tank along the first pipeline, and based on the arrangement of a spiral pressurization structure, the reaction gas and the polishing solution can form a vortex and are fully mixed to form a polishing medium; one part of the reaction gas is dissolved in the polishing solution under high pressure, and the other part of the reaction gas is suspended in the polishing solution in a bubble structure; the polishing liquid mixed with the reaction gas flows out through the second pipe. Through above-mentioned technical scheme, the composition of reaction gas, pressure and the composition of polishing solution all can allocate the setting according to the production demand to can prepare the polishing medium that satisfies high efficiency polishing and high-quality polishing.

Further, the polishing solution preparation device further comprises a third pipeline and a gas storage tank, wherein one end of the third pipeline is connected with the gas inlet of the pneumatic pump, and the other end of the third pipeline is connected with the gas outlet of the gas storage tank.

Further, a valve for controlling the flow of the fluid in the second pipeline is arranged on the second pipeline.

Further, the spiral pressurizing structure 5 comprises a body and a through hole arranged on the side wall of the body, a spiral channel is arranged in the body along the axial direction of the body, and the through hole is communicated with the thread channel; the spiral channel at least satisfies one of the following conditions:

(a) the pitch of the spiral channel is decreased progressively along the axial direction of the body;

(b) the diameter of the cross section of the spiral channel is gradually reduced along the axial direction of the body;

(c) the diameter of the spiral channel decreases progressively along the axial direction of the body.

In another specific embodiment, the spiral pressurizing structure comprises a body and a through hole arranged on the side wall of the body, the inner wall of the body is provided with spiral channels distributed along the axial direction of the body, a central column is arranged in the body along the axial direction of the body, and a certain gap is arranged between the side wall of the central column and the side wall of the spiral channel or the side wall of the central column; the through hole is communicated with the thread channel;

the spiral channel at least satisfies one of the following conditions:

(a) the pitch of the spiral channel is decreased progressively along the axial direction of the body;

(b) the diameter of the cross section of the spiral channel is gradually reduced along the axial direction of the body;

(c) the diameter of the spiral channel decreases progressively along the axial direction of the body.

The second aspect of the present invention provides a polishing medium preparation method, in which the polishing medium preparation apparatus is used to prepare a polishing medium, the polishing medium preparation method including: storing at least one of hydrogen, helium, nitrogen, oxygen, fluorine, neon, chlorine, argon, ozone, ammonia, carbon dioxide and nitrogen dioxide in the gas storage tank; storing polishing solution in the liquid storage tank; and releasing gas with preset pressure into the liquid storage tank by using the pneumatic pump, and promoting the gas to be fully mixed with polishing liquid by using the spiral pressurizing structure so as to obtain a polishing medium.

Reaction gas is pressurized by the pneumatic pump and then injected into the liquid storage tank along the first pipeline, and based on the arrangement of a spiral pressurization structure, the reaction gas and the polishing solution can form a vortex and are fully mixed to form a polishing medium; one part of the reaction gas is dissolved in the polishing solution under high pressure, and the other part of the reaction gas is suspended in the polishing solution in a bubble structure; the polishing liquid mixed with the reaction gas flows out through the second pipe. Through above-mentioned technical scheme, the composition of reaction gas, pressure and the composition of polishing solution all can allocate the setting according to the production demand to can prepare the polishing medium that satisfies high efficiency polishing and high-quality polishing.

Further, after the pressure of the gas released from the gas storage tank is increased to 0-500kPa by using the pneumatic pump, the gas is released into the liquid storage tank;

storing oxygen, nitrogen, argon and air in the gas storage tank;

or the like, or, alternatively,

storing oxygen in the gas storage tank;

or the like, or, alternatively,

storing air in the air reservoir;

or the like, or, alternatively,

and storing oxygen and nitrogen in the gas storage tank.

Further, polishing particles are added into the polishing solution, and the polishing particles are at least one of diamond, cubic boron nitride, boron carbide, silicon carbide, aluminum oxide, cerium oxide, silicon oxide, titanium oxide, zirconium oxide and manganese oxide; the polishing particles account for 5-30 wt% of the polishing solution; the grain diameter of the polishing particles is 0.05-1 mu m;

adding a chemical additive into the polishing solution, wherein the chemical additive is at least one of acid, alkali, salt metal oxide and non-metal oxide, and the chemical additive accounts for 0-10 wt% of the polishing solution.

The invention provides a mechanical chemical polishing device in a third aspect, which comprises a mechanical chemical processing chamber and a polishing medium preparation device;

the mechanochemical processing chamber also comprises a bracket, a polishing disk arranged on the bracket, a motor arranged below the polishing disk and used for driving the polishing disk to rotate, a polishing pad adhered to the upper surface of the polishing disk, a pressure weight positioned above the polishing disk and a driving mechanism used for driving the pressure weight to rotate; the polishing medium is capable of flowing through a second conduit to the upper surface of the polishing pad.

The polishing medium prepared by the polishing medium preparation device is conveyed to the polishing pad, and the semiconductor material is polished by the mechanochemical processing chamber, so that the polishing efficiency and the polishing quality of the semiconductor material are improved

The invention provides a mechanochemical polishing method, which is used for carrying out mechanochemical polishing on a semiconductor material by utilizing the mechanochemical polishing equipment;

attaching a semiconductor material to be polished to the lower end face of the pressure weight, conveying the polishing medium to the polishing pad, driving the polishing disc to rotate by the motor, and driving the pressure weight to rotate on the upper surface of the polishing pad by the driving mechanism.

Reaction gas is pressurized by the pneumatic pump and then injected into the liquid storage tank along the first pipeline, and based on the arrangement of a spiral pressurization structure, the reaction gas and the polishing solution can form a vortex and are fully mixed to form a polishing medium; one part of the reaction gas is dissolved in the polishing solution under high pressure, and the other part of the reaction gas is suspended in the polishing solution in a bubble structure; the polishing liquid (i.e., polishing medium) mixed with the reaction gas flows into the mechanochemical processing chamber through the second pipeline, specifically flows on the polishing pad, then the motor drives the polishing disk to rotate, and the driving mechanism drives the pressure weight to rotate on the upper surface of the polishing pad so as to polish the semiconductor material.

Through the technical scheme, the polishing efficiency and the polishing quality of the semiconductor material can be effectively improved

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

FIG. 1 is a schematic structural view of one embodiment of a polishing medium preparation apparatus or mechanochemical polishing apparatus of the present invention;

FIG. 2 is a front view of one embodiment of the screw pressurizing structure of the present invention;

FIG. 3 is a cross-sectional view taken along A-A of FIG. 2;

FIG. 4 is a cross-sectional view of another embodiment of a plenum screw structure;

FIG. 5 is a graph showing the results of a mechanochemical polishing experiment of example 1;

FIG. 6 is a graph showing the results of a mechanochemical polishing experiment of example 2;

FIG. 7 is a graph showing the results of a mechanochemical polishing experiment of example 3;

FIG. 8 is a graph showing the results of the mechanochemical polishing experiment of example 4.

Description of the reference numerals

1 liquid storage tank 2 pneumatic pump

3 first pipe 4 second pipe

5 third pipeline of spiral supercharging structure 6

7 gas storage tank 8 valve

9 bracket 10 polishing disk

11 electric machine 12 polishing pad

13 pressure weight 14 pressure gauge

51 body 52 through hole

53 center post of spiral channel 54

Detailed Description

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

In the present invention, the use of the terms of orientation such as "upper and lower" in the case where no description is made to the contrary generally means the orientation in the assembled and used state. "inner and outer" refer to the inner and outer contours of the respective component itself.

A first aspect of the present invention provides a polishing medium preparation apparatus, as shown in fig. 1, including a liquid storage tank 1 for storing polishing liquid, a pneumatic pump 2 for releasing gas of a predetermined pressure into the liquid storage tank 1, a first pipe 3, and a second pipe 4; one end of the first pipeline 3 is connected with an air outlet of the pneumatic pump 2, and the other end of the first pipeline extends to the bottom of the liquid storage tank 1 from a liquid inlet of the liquid storage tank 1; the second pipeline 4 extends from the bottom of the liquid storage tank 1 to the outside of the liquid storage tank 1; one end of the first pipeline 3 extending to the bottom of the liquid storage tank 1 is provided with a spiral pressurizing structure 5 with a spiral pressurizing structure, and the spiral pressurizing structure 5 is used for promoting the gas released from the first pipeline 3 to be fully mixed with the polishing liquid in the liquid storage tank 1 so as to form a polishing medium.

Reaction gas is pressurized by the pneumatic pump 2 and then injected into the liquid storage tank 1 along the first pipeline 3, and the reaction gas and the polishing solution can form a vortex based on the arrangement of the spiral pressurizing structure 5 and are fully mixed to form a polishing medium; one part of the reaction gas is dissolved in the polishing solution under high pressure, and the other part of the reaction gas is suspended in the polishing solution in a bubble structure; the polishing liquid, i.e., the polishing medium mixed with the reaction gas flows out through the second pipe 4. Through above-mentioned technical scheme, the composition of reaction gas, pressure and the composition of polishing solution all can allocate the setting according to the production demand to can prepare the polishing medium that satisfies high efficiency polishing and high-quality polishing.

The polishing solution preparation device further comprises a third pipeline 6 and a gas storage tank 7, one end of the third pipeline 6 is connected with the gas inlet of the pneumatic pump 2, and the other end of the third pipeline is connected with the gas outlet of the gas storage tank 7. A valve 8 for controlling the flow of fluid in the second pipe 4 is arranged on the second pipe 4.

Several embodiments of the screw supercharging structure 5 are provided below: