CN221416244U - Cleaning device for chemical mechanical polishing - Google Patents

Abstract

Embodiments of the present utility model relate to a cleaning apparatus for chemical mechanical polishing. The present utility model proposes a cleaning device for chemical mechanical polishing, comprising: a base having a chamber formed therein for accommodating a cleaning liquid; a piston assembly, a first end of which is disposed in the chamber such that the piston assembly is movable under the action of the cleaning fluid; and a cleaning brush disposed at a second end of the piston assembly; wherein the piston assembly includes a liquid passage therethrough such that the cleaning liquid can reach the second end of the piston assembly through the liquid passage and clean the cleaning object together with the cleaning brush. According to the utility model, the diamond disk for chemical mechanical polishing can be properly cleaned, thereby improving the adjusting efficiency of the diamond disk, prolonging the service life of the polishing pad and improving the stability of the chemical mechanical polishing process.

Description

Cleaning device for chemical mechanical polishing

Technical Field

The utility model relates to the technical field of wafer manufacturing, in particular to a cleaning device for chemical mechanical Polishing (CHEMICAL MECHANICAL CMP).

Background

Wafer fabrication includes several process flows, such as: photolithography, etching, film growth, diffusion, ion implantation, chemical mechanical polishing/polishing, metallization, and the like. Chemical Mechanical Polishing (CMP) is a process used to planarize and polish the surface of semiconductor materials, as one of the key process steps in wafer fabrication. CMP is often used to remove surface non-uniformities to a more planar state during wafer fabrication.

CMP combines the surface of a material with the friction between a chemical solution (e.g., slurry) and abrasive particles. The chemicals in the slurry may react with the surface material to help remove non-uniform portions. At the same time, the abrasive particles act on the surface during the rubbing process, further promoting planarization of the material. CMP has a key role in semiconductor fabrication because it ensures good contact between different levels and provides more reliable electronic component performance.

For wafer fabrication, a polishing pad (pad) is typically used in conjunction with a polishing slurry to polish the wafer during the CMP process. During operation, the polishing pad can rotate about its central axis under the drive of the drive device. In addition, a conditioner (conditioner) including a conditioner (disk) is also used in the CMP process to condition, clean or restore the polishing pad. That is, the conditioner is used to restore the surface of the polishing pad to its properties after polishing, thereby maintaining a stable removal rate throughout the life of the polishing pad and the healer. Typically, the prosthetic device is diamond embedded and mounted as a consumable on the regulator.

During conditioning, the diamond cuts the surface of the polishing pad and cleans the grooves of the polishing pad, which is a key factor in stabilizing the removal rate of the polishing pad. However, the surface of the conditioner is easily clogged with the viscous polishing liquid, which reduces the cleaning performance, thereby affecting the handling performance of the polishing pad.

In the prior art, deionized water is typically used to flush the healer, but this is not effective in removing all of the plugs because some of the remaining slurry is viscous and electrically charged. In a worse case, in order to solve the problem of the decrease in the polishing pad removal rate, the repairing device has to be replaced at a higher frequency.

For the above reasons, consumables used in the CMP process, including the polishing pad, the healer, and the like, cannot be fully utilized, thereby increasing costs and affecting the time for consumable replacement.

Therefore, how to overcome the defect of poor cleaning effect of the repairing device in the CMP process and improve the stability of the CMP process becomes a problem to be solved in the field.

The information disclosed in the background section is only for enhancement of understanding of the general background of the utility model and is not to be taken as an acknowledgement or default that such information forms the prior art that is already known to those of skill in the art.

Disclosure of utility model

In view of the foregoing circumstances in the art, an object of the present utility model is to provide a technique capable of improving the cleaning effect of a repairing device in a CMP process and improving the stability of the CMP process.

According to an aspect of the present utility model, there is provided a cleaning apparatus for chemical mechanical polishing, the cleaning apparatus comprising: a base having a chamber formed therein for accommodating a cleaning liquid; a piston assembly, a first end of which is disposed in the chamber such that the piston assembly is movable under the action of the cleaning fluid; and a cleaning brush disposed at a second end of the piston assembly; wherein the piston assembly includes a liquid passage therethrough such that the cleaning liquid can reach the second end of the piston assembly through the liquid passage and clean the cleaning object together with the cleaning brush.

According to a specific embodiment of the present utility model, the second end of the piston assembly forms a circular upper pressure plate, the cleaning brush is formed in a circular shape, and the upper pressure plate is concentric with the cleaning brush.

According to a specific embodiment of the present utility model, the cleaning brush is disposed eccentrically to the cleaning object so that the cleaning brush can cover the entire surface to be cleaned of the cleaning object when the cleaning object rotates.

According to a specific embodiment of the present utility model, the cleaning device further includes a cup-shaped cleaning cover that is provided above the base and surrounds the cleaning brush and the upper platen.

According to an embodiment of the present utility model, the liquid passage forms a nozzle at the second end of the piston assembly to spray the cleaning liquid to the cleaning object.

According to a specific embodiment of the utility model, the nozzle is located in the center of the cleaning brush.

According to a specific embodiment of the utility model, the base comprises a water inlet for injecting the cleaning liquid into the chamber.

According to a specific embodiment of the utility model, the water inlet is connected to a supply of liquid, so that cleaning liquid of different pressures can be injected into the chamber.

According to a specific embodiment of the utility model, the first end of the piston assembly divides the chamber into an upper chamber and a lower chamber, the base comprising a vent and an overflow, wherein the upper chamber is communicable with the vent and the lower chamber is communicable with the overflow.

According to an embodiment of the present utility model, the cleaning object is a diamond disk for chemical mechanical polishing.

Furthermore, particular embodiments of the utility model may include any optional features that enable the objects of the utility model to be achieved.

According to the embodiment of the utility model, the diamond disk for chemical mechanical polishing can be properly cleaned, so that the polishing pad adjusting efficiency is improved, the service life of the polishing pad is prolonged, and the stability of the chemical mechanical polishing process is improved.

In accordance with an embodiment of the present utility model, a cup-shaped automatic polishing pad conditioner cleaning device is provided for timely and thorough cleaning of the surface of a prosthetic appliance (e.g., diamond-impregnated diamond disk). In the adjusting process of the grinding pad, the surface of the diamond disc is physically cleaned by adopting the cleaning brush with the function of automatically adjusting the height, and meanwhile, the diamond disc is cleaned by high-pressure deionized water, so that the cleaning efficiency is greatly improved.

According to an embodiment of the present utility model, the diamond protrusion height of the surface of the prosthetic appliance is maintained in a good state by a physical method, thereby effectively adjusting the polishing pad. The cleaning device timely removes the residue of the grinding fluid, so that the stability of the CMP process is greatly improved. With increased cleanliness of the restorations, the life of CMP consumables, such as polishing pads and restorations, is extended by at least 15%, e.g., the life of polishing pads and/or restorations is extended from 1500pcs (pieces) to 1800pcs, as the process becomes more stable and reliable.

Other advantageous technical effects that can be achieved by embodiments of the present utility model will be understood and appreciated by those skilled in the art from a reading of the present specification.

Drawings

Fig. 1 is a schematic view illustrating a cleaning apparatus for chemical mechanical polishing according to an embodiment of the present utility model.

Fig. 2 is a schematic view illustrating an application scenario of a cleaning apparatus for chemical mechanical polishing according to an embodiment of the present utility model.

For clarity of description, parts not substantially germane to the technique of the present utility model are omitted; and in the description and drawings, identical or similar elements are denoted by the same reference numerals. It should be understood that the drawings are presented in order to illustrate the general principles and various features of the utility model and that the scope of the utility model is not limited to the form shown in the drawings.

Reference numerals illustrate:

10. a base;

20. A piston assembly;

30. A cleaning brush;

40. a cleaning cover;

100. A cleaning object;

12. A chamber;

14. A water inlet;

22. An upper press plate;

24. A nozzle;

122. a vent;

124. An overflow port;

200. A polishing pad conditioner;

300. A repairer;

400. A cleaning device.

Detailed Description

Embodiments of the present utility model will be described in detail below with reference to the accompanying drawings. While the utility model is described in conjunction with the exemplary embodiments, it will be understood that this description is not intended to limit the utility model to these exemplary embodiments. On the contrary, the utility model is intended to cover not only these exemplary embodiments, but also various alternatives, modifications, and equivalents, which may be included within the spirit and scope of the utility model as defined by the appended claims.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model; the terms "comprising," "including," and "having" and any variations thereof, as used in the description and claims of the present utility model, are intended to be non-exclusive.

In the description of embodiments of the present application, the technical terms "first," "second," and the like are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.

In the description of embodiments of the application, when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or one or more intervening elements may also be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present.

For convenience in explanation and accurate definition in the appended claims, the terms "inner", "outer", "upper", "lower", "front", "rear", and etc. are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

Fig. 1 is a schematic view illustrating a cleaning apparatus for chemical mechanical polishing according to an embodiment of the present utility model.

As shown in fig. 1, a cleaning apparatus for chemical mechanical polishing according to an embodiment of the present utility model includes: a base 10 having a chamber 12 formed therein for accommodating a cleaning liquid; a piston assembly 20 having a first end disposed in the chamber 12 such that the piston assembly 20 is movable under the influence of the cleaning fluid; and a cleaning brush 30 provided at a second end of the piston assembly 20; wherein the piston assembly 20 includes a liquid passage therethrough so that the cleaning liquid can reach the second end of the piston assembly 20 through the liquid passage and clean the cleaning object 100 together with the cleaning brush 30.

Preferably, the cleaning solution may be deionized water. Deionized water is specially treated water, which is purified water obtained by removing ions and soluble solid substances therein. Deionized water may be used to clean and rinse chips, wafers, and other electronic components during semiconductor manufacturing. The purity of the cleaning agent can ensure that the surface of the cleaning object is not polluted by ions and impurities, and the performance and reliability of chips, wafers and other electronic elements are ensured.

Cleaning brush 30 contacts the surface of the prosthetic appliance and is a consumable material in the CMP process and needs to be replaced periodically. Preferably, the cleaning brush 30 is formed in a circular ring shape, with a nozzle 24 capable of spraying cleaning liquid at the center.

Thus, during operation of the cleaning device, the height of the cleaning brush can be controlled and regulated by means of the pressure of the cleaning liquid (e.g., deionized water), thereby effectively physically cleaning the surface of the prosthetic appliance (e.g., diamond disk), while the cleaning liquid also cleans the prosthetic appliance at a certain pressure. In this way, the cleaning efficiency is improved and enhanced. In other words, by properly cleaning the diamond disk for CMP, the polishing pad conditioning efficiency is improved, and the service life of the polishing pad is prolonged, thereby improving the stability of the CMP process.

According to the cleaning apparatus for chemical mechanical polishing of the embodiment of the present utility model, the second end of the piston assembly 20 is formed into a circular upper platen 22, the cleaning brush 30 is formed into a circular shape, and the upper platen 22 is concentric with the cleaning brush 30. Further, the cleaning brush 30 is eccentrically disposed from the cleaning object 100, so that the cleaning brush 30 can cover the entire surface to be cleaned of the cleaning object 100 when the cleaning object 100 rotates. In addition, the cleaning apparatus for chemical mechanical polishing according to the embodiment of the present utility model further includes a cup-shaped cleaning cap 40, and the cleaning cap 40 is disposed above the base 10 and surrounds the cleaning brush 30 and the upper platen 22.

The upper platen 22 and the cleaning brush 30, which are both circular and concentric with each other, form a compact structure, thereby contributing to the overall compact construction of the cleaning apparatus. The cleaning object 100 is, for example, a circular diamond disk, the center of which is eccentrically disposed with the center of the cleaning brush 30; since the diamond disk can be rotated by a driving device (not shown) and can be displaced in a horizontal direction, the cleaning brush 30 can cover the entire surface to be cleaned of the cleaning object 100, for example, the lower surface in fig. 1. A cup-shaped cleaning cap 40 is detachably or integrally provided above the base 10 to cover a cleaning portion between the cleaning brush 30 and the cleaning object 100 from bottom to top, thereby preventing the cleaning liquid from overflowing or splashing out and from affecting other parts or operators of the CMP process.

According to the cleaning apparatus for chemical mechanical polishing of the embodiment of the present utility model, the liquid passage forms the nozzle 24 at the second end of the piston assembly 20 to spray the cleaning liquid to the cleaning object 100. In addition, the nozzle 24 is located at the center of the cleaning brush 30.

The nozzle 24 constitutes an outlet for the cleaning liquid. Nozzle 24 is centered on cleaning brush 30, which is the most efficient location for cleaning. In addition, the nozzle 24 may be sized to spray cleaning fluid while also maintaining the hydraulic pressure of the chamber 12. For example, the nozzle 24 may form a spray area of 0.5mm ² and a spray angle of 120 degrees, thereby forming a spray flow of 3.5L/min. It will be appreciated by those skilled in the art that the above parameters are merely examples and are not limiting on the scope of the utility model.

According to the cleaning apparatus for chemical mechanical polishing of the embodiment of the present utility model, the susceptor 10 includes a water inlet 14 for injecting a cleaning liquid into the chamber 12. Furthermore, the water inlet 14 is connected to a supply (not shown) so that cleaning liquid of different pressures can be injected into the chamber 12.

The water inlet 14 may be located at any suitable location on the base 10 for injecting cleaning fluid into the chamber 12. The liquid supply may be a water supply capable of increasing the cleaning liquid with different hydraulic pressures. The hydraulic pressure of the liquid supply source may be set according to the total weight of the cleaning device and/or the required injection pressure of the cleaning liquid. In addition, the pressure of the cleaning liquid can be regulated by a regulator.

According to the cleaning apparatus for chemical mechanical polishing of the embodiment of the present utility model, the first end of the piston assembly 20 divides the chamber 12 into an upper chamber and a lower chamber, the susceptor 10 includes a vent 122 and an overflow 124, wherein the upper chamber can communicate with the vent 122, and the lower chamber can communicate with the overflow 124.

The height of overflow 124 may be determined based on the position at which cleaning brush 30 is operating properly. Since the cleaning brush 30 is a consumable, the bristle length thereof is gradually shortened during operation. To maintain the cleaning ability of the cleaning brush 30, the hydraulic pressure of the cleaning liquid may be increased so that the piston assembly 20 moves upward together with the cleaning brush 30. However, if the piston assembly 20 moves too far, the overflow port 124 may be opened so that cleaning fluid is discharged therefrom. Therefore, by providing the overflow port 124, it is possible to detect whether the cleaning brush 30 has been excessively consumed. In addition, the vent 122 communicating with the upper chamber may release gas in the upper chamber when the piston assembly 20 moves upward, preventing too small a gap between the piston assembly 20 and the base 10 from causing a pressure increase to hinder movement of the piston assembly 20.

According to the cleaning apparatus for chemical mechanical polishing of the embodiment of the present utility model, the cleaning object 100 is a diamond disk for chemical mechanical polishing.

The cleaning object 100 may also be other components used in the CMP process depending on the application of the present utility model.

Fig. 2 is a schematic view illustrating an application scenario of a cleaning apparatus for chemical mechanical polishing according to an embodiment of the present utility model.

As shown in fig. 2, the conditioner 300 is disposed on the right side of the polishing pad conditioner 200, and the cleaning device 400 is disposed below the conditioner 300. In the operation of the cleaning apparatus 400, the height-adjustable cleaning brush included therein physically cleans the surface of the prosthetic appliance 300 while cleaning with deionized water, thereby greatly improving the cleaning efficiency and the stability of the CMP process.

For example, in the context of the present utility model, after the diamond disk completes conditioning of the polishing pad, it will return to the cleaning device position at a certain rate. Deionized water fills the chamber and creates pressure, which then pushes the piston assembly upward. The cleaning brush contacts the diamond disk for physical cleaning, and meanwhile deionized water is sprayed out from the nozzle at a high speed to take away impurities.

The flow rate of the nozzle is controlled by the water pressure and the nozzle size and should be regulated by an upstream regulator.

The flow and water pressure relationship may be calculated based on the total weight of the cleaning brush, upper platen, piston assembly, etc. If the total weight is high, a high water pressure value can be set in the chamber to achieve a high flow rate. For example, for the case of 300g of the total weight described above, a flow rate of 3.5 to 4L/min may be achieved.

According to embodiments of the utility model, the prosthetic life may be extended by 20%. Considering CMP practices, the cost benefit per wafer is about $0.12 considering both the healer and the polishing pad.

Furthermore, if the diamond disk is not in the correct position of the cleaning device or the cleaning brush is excessively consumed, the piston assembly will move more distance and open the overflow port. Water will escape from the overflow port and the water flow will increase more as the pressure decreases. This can be detected by the water flow meter.

In addition, the cleaning brush is a consumable and needs to be replaced periodically, otherwise the cleanliness is affected.

In addition, if the cleaning water pressure is too low, the cleaning brush does not contact the diamond disk, and the frictional force is different from that in a standard state, which can be detected by the polishing pad conditioner rotating motor.

The foregoing description of specific exemplary embodiments of the utility model has been presented for the purposes of illustration and description. The foregoing description is not intended to be exhaustive or to limit the utility model to the precise form disclosed. Obviously many modifications and variations will be apparent to those skilled in the art in light of the above teachings. The exemplary embodiments were chosen and described in order to explain the principles of the utility model and its practical application to thereby enable one skilled in the art to make and use various exemplary embodiments of the utility model and various alternatives and modifications thereof. Indeed, the scope of the utility model is defined by the appended claims and equivalents thereof.

Claims (10)

1. A cleaning apparatus for chemical mechanical polishing, the cleaning apparatus comprising:

A base having a chamber formed therein for accommodating a cleaning liquid;

A piston assembly, a first end of which is disposed in the chamber such that the piston assembly is movable under the action of the cleaning fluid; and

A cleaning brush disposed at a second end of the piston assembly;

Wherein the piston assembly includes a liquid passage therethrough such that the cleaning liquid can reach the second end of the piston assembly through the liquid passage and clean the cleaning object together with the cleaning brush.

2. The cleaning device of claim 1, wherein the second end of the piston assembly forms a circular upper platen, the cleaning brush forms a circular shape, and the upper platen is concentric with the cleaning brush.

3. The cleaning apparatus according to claim 2, wherein the cleaning brush is disposed eccentrically to the cleaning object so that the cleaning brush can cover the entire surface to be cleaned of the cleaning object when the cleaning object rotates.

4. The cleaning device of claim 2, further comprising a cup-shaped cleaning hood disposed above the base and surrounding the cleaning brush and the upper platen.

5. The cleaning apparatus of claim 1, wherein the liquid passage forms a nozzle at a second end of the piston assembly to spray the cleaning liquid to the cleaning object.

6. The cleaning device of claim 5, wherein the nozzle is located in the center of the cleaning brush.

7. The cleaning device of claim 1, wherein the base includes a water inlet for injecting the cleaning fluid into the chamber.

8. The cleaning apparatus of claim 7, wherein the water inlet is connected to a supply of liquid so that cleaning liquid of different pressures can be injected into the chamber.

9. The cleaning apparatus defined in claim 1, wherein the first end of the piston assembly divides the chamber into an upper chamber and a lower chamber, the base comprising a vent port and an overflow port, wherein the upper chamber is communicable with the vent port and the lower chamber is communicable with the overflow port.

10. The cleaning apparatus according to claim 1, wherein the cleaning object is a diamond disk for chemical mechanical polishing.