阅读说明：本技术 一种晶圆固定环及具有其的cmp设备 (Wafer fixing ring and CMP equipment with same ) 是由 唐强 蒋锡兵 于 2021-10-08 设计创作，主要内容包括：本发明涉及半导体CMP加工技术领域,具体涉及一种晶圆固定环及具有其的CMP设备。晶圆固定环,包括：支撑件；研磨环,平行安装在支撑件的一侧,研磨环上间隔设有多个凹槽,凹槽朝向支撑环延伸且凹槽贯穿研磨环设置；伸缩组件,安装在支撑件与研磨环之间,伸缩组件具有延伸至凹槽内以将凹槽完全填充的清洁状态,以及从凹槽内撤出的研磨状态。在清洁时控制伸缩组件在凹槽内伸长至清洁状态,使得伸缩组件将凹槽填充同时将凹槽中的残留物推出,配合高压喷水清洁,能够快速便捷地将凹槽内的研磨残留物清除,能够避免凹槽中的研磨残留物对后续研磨抛光的晶圆造成影响,能够大大提升整个批次上所有晶圆的整体质量。(The invention relates to the technical field of semiconductor CMP processing, in particular to a wafer fixing ring and CMP equipment with the same. The wafer retaining ring includes: a support member; the grinding ring is arranged on one side of the supporting piece in parallel, a plurality of grooves are formed in the grinding ring at intervals, the grooves extend towards the supporting ring, and the grooves penetrate through the grinding ring; a retraction assembly mounted between the support and the abrasive ring, the retraction assembly having a cleaning state extending into the groove to completely fill the groove and an abrasive state withdrawn from the groove. The telescopic component is controlled to extend in the groove to a clean state during cleaning, so that the telescopic component fills the groove and pushes out residues in the groove, the telescopic component is matched with high-pressure water spraying cleaning, the grinding residues in the groove can be rapidly and conveniently cleared away, the influence of the grinding residues in the groove on subsequent grinding and polishing wafers can be avoided, and the overall quality of all wafers in the whole batch can be greatly improved.)

1. A wafer retaining ring, comprising:

a support member;

the grinding ring (2) is arranged on one side of the support in parallel, a plurality of grooves (4) are formed in the grinding ring (2) at intervals, the grooves (4) extend towards the support ring (1), and the grooves (4) penetrate through the grinding ring (2);

a telescopic assembly (3) mounted between the support and the grinding ring (2), the telescopic assembly (3) having a cleaning state extending into the groove (4) to completely fill the groove (4), and an abrasive state withdrawn from within the groove (4).

2. The wafer retaining ring according to claim 1, wherein the retraction assembly (3) comprises an elastic retraction member and an ejector member, the ejector member is slidably engaged with the side wall of the groove (4), and the elastic retraction member is disposed on a side of the ejector member facing the support member.

3. The wafer fixing ring according to claim 2, wherein the elastic expansion member is an elastic membrane structure, an inflation channel (5) is arranged on the support member, the elastic membrane structure is sealed with an outlet end of the inflation channel (5), and when the expansion assembly (3) is in a cleaning state, the elastic membrane structure is inflated to bulge towards the groove (4) to drive the ejector to move away from the support member; when the telescopic assembly (3) is in a grinding state, the elastic membrane structure is pumped and swells towards the inflation flow channel (5) so as to drive the ejection piece to move close to the support piece.

4. The wafer retaining ring of claim 2 or 3, wherein the ejector is of a flat plate structure, and when the expansion assembly (3) is in a cleaning state, the ejector is flush with a surface of the polishing ring (2) facing away from the support.

5. The wafer retaining ring of claim 2 or 3, wherein the ejector member is of an arc-shaped plate structure, and the protruding surface of the ejector member is fixedly connected with the elastic expansion member.

6. The wafer retaining ring according to any one of claims 1 to 3, wherein a plurality of the telescopic assemblies (3) are provided, and the telescopic assemblies (3) and the grooves (4) are arranged in a one-to-one correspondence.

7. The wafer retaining ring according to any one of claims 1 to 3, wherein a mounting groove is formed on a surface of the support facing the polishing ring (2), the mounting groove and the groove (4) are arranged in a one-to-one correspondence, and when the expansion assembly (3) is in a cleaning state, the expansion assembly (3) extends from the inside of the mounting groove to the inside of the groove (4).

8. The wafer retaining ring according to any one of claims 1 to 3, wherein the support is an annular structure disposed coaxially with the grinding ring (2).

9. The wafer retaining ring according to any one of claims 1 to 3, wherein the grooves (4) have a depth of 2.5mm to 3 mm.

10. A CMP apparatus, characterized by having the wafer retaining ring of any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of semiconductor CMP processing, in particular to a wafer fixing ring and CMP equipment with the same.

Background

Cmp (chemical Mechanical planarization) is a chemical Mechanical polishing process that uses chemical etching and Mechanical forces to planarize silicon wafers or other substrate materials during processing. During the modern semiconductor manufacturing chemical mechanical polishing process, a retaining ring on a polishing head is used to hold a wafer within the ring during the manufacturing semiconductor wafer polishing process to polish a single side of the wafer. Conventional retaining ring surfaces are comprised of a fixed number and size of grooves, which limits the drainage of slurry byproducts.

The CMP chemical corrosive liquid can generate corresponding byproduct residues after reacting with metal on the surface of a wafer, the byproducts are discharged after being ground by the grinding liquid, the residues in the grooves of the grinding pad can be continuously increased along with the continuous grinding of the grinding pad due to the structural fixity of the fixing ring and the chemical reaction of the byproducts, the residues deposited in the grooves of the grinding pad of the fixing ring can influence the subsequently ground wafer to a certain extent, and various residue defects can be generated on the ground wafer.

Disclosure of Invention

Therefore, the present invention is directed to overcome the defect that the residue accumulation in the polishing pad groove of the CMP wafer retaining ring in the prior art affects the polishing quality of the subsequent wafer, and provides a wafer retaining ring and a CMP apparatus having the same.

In order to solve the above technical problems, the present invention provides a wafer retaining ring, comprising:

a support member;

the grinding ring is arranged on one side of the supporting piece in parallel, a plurality of grooves are formed in the grinding ring at intervals, the grooves extend towards the supporting ring, and the grooves penetrate through the grinding ring;

a retraction assembly mounted between the support and the abrasive ring, the retraction assembly having a cleaning state extending into the groove to completely fill the groove and an abrasive state withdrawn from the groove.

Optionally, the telescopic assembly comprises an elastic telescopic part and an ejector part, the ejector part is in sliding fit with the side wall of the groove, and the elastic telescopic part is arranged on one side of the ejector part facing the support part.

Optionally, the elastic expansion part is of an elastic membrane structure, the supporting part is provided with an inflation channel, the elastic membrane structure is arranged at the outlet end of the inflation channel in a sealing manner, and when the expansion assembly is in a cleaning state, the elastic membrane structure is inflated to bulge towards the groove so as to drive the ejection part to move away from the supporting part; when the telescopic assembly is in a grinding state, the elastic membrane structure is pumped and swells towards the inflation runner so as to drive the ejection piece to move close to the support piece.

Optionally, the ejector member is of a flat plate structure, and when the telescopic assembly is in a cleaning state, the ejector member is flush with one surface of the grinding ring, which is away from the supporting member.

Optionally, the ejector is of an arc-shaped plate structure, and a protruding surface of the ejector is fixedly connected with the elastic telescopic piece.

Optionally, the telescopic assemblies are provided in a plurality, and the telescopic assemblies and the grooves are arranged in a one-to-one correspondence manner.

Optionally, support piece is equipped with the mounting groove in the one side of grinding ring, and the mounting groove sets up with the recess one-to-one, and when flexible subassembly was in clean state, flexible subassembly extended to in the recess from the mounting groove.

Optionally, the support is an annular structure disposed coaxially with the grinding ring.

Optionally, the groove depth is 2.5mm to 3 mm.

The invention also provides CMP equipment which is provided with the wafer fixing ring.

The technical scheme of the invention has the following advantages:

1. the invention provides a wafer fixing ring, comprising: a support member; the grinding ring is arranged on one side of the supporting piece in parallel, a plurality of grooves are formed in the grinding ring at intervals, the grooves extend towards the supporting ring, and the grooves penetrate through the grinding ring; a retraction assembly mounted between the support and the abrasive ring, the retraction assembly having a cleaning state extending into the groove to completely fill the groove and an abrasive state withdrawn from the groove.

When the wafer fixing ring is used for grinding and polishing the wafer, the wafer is placed in the grinding ring, the supporting piece presses downwards to apply certain pressure to the wafer and then the wafer is subjected to rotary grinding, and meanwhile, grinding liquid enters the bottom of the wafer on the inner side of the grinding ring from the groove. After finishing grinding, cleaning operation is carried out on the wafer fixing ring, the telescopic component is controlled to extend in the groove to a cleaning state when cleaning, so that the telescopic component fills the groove and pushes out residues in the groove, cleaning is carried out by matching with high-pressure water spraying, the grinding residues in the groove can be quickly and conveniently removed, influence of the grinding residues in the groove on subsequent grinding and polishing wafers can be avoided, and the overall quality of all wafers in the whole batch can be greatly improved. After the cleaning is finished, the telescopic assembly is controlled to retract, the telescopic assembly is withdrawn from the groove to a grinding state, and the groove can be exposed again for subsequent grinding operation.

2. The invention provides a wafer fixing ring.A telescopic component comprises an elastic telescopic piece and an ejecting piece, wherein the ejecting piece is in sliding fit with the side wall of a groove, and the elastic telescopic piece is arranged on one side of the ejecting piece facing a supporting piece. The elastic telescopic piece is used for driving the ejection piece to move in the groove, the elastic telescopic piece is used for driving the ejection piece to move, and the ejection piece is used for ejecting residues in the groove out of the groove.

3. According to the wafer fixing ring provided by the invention, the ejection piece is of a flat plate structure, and when the telescopic assembly is in a cleaning state, the ejection piece is flush with one surface of the grinding ring, which is far away from the support piece. The liftout piece of flat structure when clean state, can be completely with the recess in the residue ejecting outside, the washing cleanness of subsequent residue of being convenient for, the residue is clear away to the at utmost, promotes the clean and tidy degree in the clean back recess.

4. According to the wafer fixing ring provided by the invention, the ejection piece is of an arc-shaped plate structure, and the protruding surface of the ejection piece is fixedly connected with the elastic telescopic piece. Through the ejector piece with the arc-shaped plate structure, the corner structures in the grooves are reduced, the residual probability of impurities in the grooves can be reduced, meanwhile, the inner side walls of the grooves can be cut and rubbed when the ejector piece with the arc-shaped plate structure slides, the situation that residues are clamped into gaps between the ejector piece and the inner side walls of the grooves when the ejector piece slides in the grooves is avoided, and the clean and tidy degree is improved.

5. According to the wafer fixing ring provided by the invention, the side, facing the grinding ring, of the supporting piece is provided with the mounting grooves, the mounting grooves and the grooves are arranged in a one-to-one correspondence mode, and when the telescopic assembly is in a cleaning state, the telescopic assembly extends into the grooves from the mounting grooves. Through setting up the mounting groove and making the subassembly that stretches out and draws back can hide in the mounting groove when grinding the state, need not to occupy the space of recess, guarantee that the solid fixed ring of wafer recess keeps penetrating when grinding work goes on.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic view of a wafer retaining ring with a retractable assembly in a polishing state according to an embodiment of the present invention.

FIG. 2 is a schematic view of a wafer retaining ring with a retractable assembly in a cleaning state according to an embodiment of the present invention.

Fig. 3 is a schematic view of a grinding ring in a grinding state of a telescopic assembly provided in an embodiment of the present invention.

FIG. 4 is a schematic view of an abrasive ring with a telescoping assembly in a cleaning state according to an embodiment of the present invention.

Description of reference numerals: 1. a support ring; 2. a grinding ring; 3. a telescoping assembly; 4. a groove; 5. an inflation channel; 6. a grinding platform.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

Fig. 1 to 4 show a wafer retaining ring provided in the present embodiment, wherein solid black dots in fig. 1 and 2 are residues. The method comprises the following steps: a support ring 1 as a support, a grinding ring 2, and a telescopic assembly 3 installed between the support ring 1 and the grinding ring 2.

The support ring 1 is coaxial with the grinding ring 2, and the diameter of the inner circle of the support ring 1 is the same as that of the inner circle of the grinding ring 2, and the diameter of the outer circle of the support ring 1 is the same as that of the outer circle of the grinding ring 2. The grinding ring 2 is installed in one side of support ring 1 in parallel, and the interval is equipped with a plurality of recesses 4 on the grinding ring 2, and recess 4 extends towards support ring 1 and recess 4 runs through the setting of grinding ring 2.

A retraction assembly 3 is mounted between the support and the abrasive ring 2, the retraction assembly 3 having a cleaning state extending into the groove 4 to completely fill the groove 4 and an abrasive state withdrawn from the groove 4. Specifically, flexible subassembly 3 includes elastic expansion piece and liftout piece, liftout piece and recess 4's lateral wall sliding fit, and elastic expansion piece locates the one side of liftout piece towards support piece.

In the embodiment, the elastic extensible member is an elastic membrane structure, the elastic membrane structure is made of rubber materials, the support member is provided with an inflation channel 5, the elastic membrane structure is arranged in a sealing manner with the outlet end of the inflation channel 5, and when the extensible assembly 3 is in a cleaning state, the elastic membrane structure is inflated to bulge towards the groove 4 so as to drive the ejection member to move away from the support member; when the telescopic assembly 3 is in a grinding state, the elastic membrane structure is pumped and swells towards the inflation runner 5 so as to drive the ejection piece to move close to the support piece. The recess 4 degree of depth in this embodiment is 2.5mm, makes flexible elastic membrane structure can bulge enough height and ejecting out the recess 4 outside through setting up the more shallow recess 4 of degree of depth, can change the position of ejecting in recess 4 through the control to elastic membrane structure's inflation pressure, convenient operation. The depth of the recess 4 may also be any of 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, as long as the ejector is able to ensure that it is at least flush with the outer edge of the recess 4 at the highest elevation of the elastomeric mould structure.

In this embodiment, the liftout is the arc structure, and tangent setting between the side of liftout and the inside wall of recess 4, the protruding face of liftout passes through glue fixed connection with the elastic membrane structure of the rubber material as elastic expansion piece. Through the ejector piece that sets up arc plate structure, reduce the corner structure in recess 4, can reduce the residual probability of impurity in recess 4, the ejector piece of arc plate structure can cut the piece and rub the inside wall of recess 4 when sliding simultaneously, cleans the inside wall of recess 4, avoids in the residual card goes into the gap between ejector piece and the recess 4 inside wall when ejector piece slides in recess 4, promotes clear clean and tidy degree.

Support ring 1 is equipped with the mounting groove in the one side of grinding ring 2, and mounting groove and recess 4 one-to-one set up, and when flexible subassembly 3 was in clean state, flexible subassembly 3's liftout piece extended to in the recess 4 from the mounting groove, and when flexible subassembly 3 was in the grinding state, flexible subassembly 3's liftout piece was hidden in the mounting groove, and the space of avoiding liftout piece to occupy recess 4 leads to being blockked up at grinding in-process recess 4.

When the wafer fixing ring provided in this embodiment is used to polish a wafer, the wafer is installed in the inner ring of the polishing ring 2, the wafer fixing ring drives the wafer to move above the polishing platform 6, the support ring 1 is rotated and polished by applying a pressure of 5.5-6.0 psi downward, and meanwhile, the polishing solution is dropped onto the polishing platform 6, enters between the wafer inside the polishing ring 2 and the polishing platform from the groove 4, and the polishing solution stops being added after polishing. Accomplish and remove pressure after grinding, lift up grinding ring 2, utilize the high-pressure squirt to wash grinding ring 2's surface, wash and overshoot, inflate elastic membrane structure through inflation flow channel 5 and make its bloated piece that drives the arc platelike ejecting of ejecting in with recess 4 grind the residue outside recess 4, cooperate the high-pressure squirt to grinding ring 2 wash, can be smoothly under the impact of grinding ring 2 with the residue. After the washing is finished, the wafer fixing ring is integrally moved to the next wafer grinding station to continue grinding, the groove 4 of the grinding ring 2 can be kept clean during subsequent grinding, damage to the wafer caused by residues in the groove 4 can be avoided, and the quality of wafer grinding and polishing can be greatly improved.

As an alternative embodiment, the telescopic assembly 3 is provided in plurality, and the telescopic assembly 3 is arranged in one-to-one correspondence with the grooves 4. Clear up a plurality of recesses 4 respectively when clean, promote clean degree after.

As an alternative embodiment, the ejector is a flat plate structure, and when the telescopic assembly 3 is in the cleaning state, the ejector is flush with the surface of the grinding ring 2 departing from the support. Dull and stereotyped structure's ejecting piece when clean state, can be totally with the residue in recess 4 ejecting to recess 4 outside, the washing cleanness of the subsequent residue of being convenient for, the at utmost clears away the residue, promotes clean and tidy degree in the back recess 4.

As an alternative embodiment, the support is a disc structure or a frame structure.

Example 2

This embodiment provides a CMP apparatus having the wafer fixing ring described in embodiment 1. When the wafer fixing ring is cleaned, the telescopic assembly is controlled to extend in the groove to a clean state, so that the telescopic assembly fills the groove and pushes out residues in the groove, the telescopic assembly is matched with high-pressure water spraying cleaning, the grinding residues in the groove can be rapidly and conveniently cleared away, the grinding residues in the groove can be prevented from influencing wafers subjected to subsequent grinding and polishing, and the overall quality of all wafers in the whole batch can be greatly improved.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.