CN110484895B

CN110484895B - Chamber assembly and reaction chamber

Info

Publication number: CN110484895B
Application number: CN201810457537.9A
Authority: CN
Inventors: 师帅涛; 丁安邦; 陈鹏; 史小平; 李春雷; 兰云峰
Original assignee: Beijing Naura Microelectronics Equipment Co Ltd
Current assignee: Beijing Naura Microelectronics Equipment Co Ltd
Priority date: 2018-05-14
Filing date: 2018-05-14
Publication date: 2021-01-08
Anticipated expiration: 2038-05-14
Also published as: KR20200130416A; TWI749301B; WO2019218765A1; KR102439759B1; CN110484895A; TW201947671A

Abstract

The invention provides a chamber component and a reaction chamber, wherein the chamber component comprises: the electrode plate is electrically connected with the radio frequency source and is provided with an air inlet; and the flow homogenizing part is made of insulating materials and forms a flow homogenizing space together with the electrode plate, the air inlet is communicated with the flow homogenizing space, the flow homogenizing part is provided with a plurality of air outlets, and the air outlets are respectively communicated with the flow homogenizing space and the reaction chamber. The chamber component provided by the invention can avoid generating hollow cathode discharge, thereby improving the stability of plasma.

Description

Chamber assembly and reaction chamber

Technical Field

The invention relates to the technical field of semiconductor manufacturing, in particular to a chamber component and a reaction chamber.

Background

In the field of semiconductor processing, feature sizes and aspect ratios are becoming more challenging as the geometries of electronic devices continue to decrease and the density of devices continues to increase. Atomic Layer Deposition (ALD) is a new method for depositing thin films to meet this challenge.

During the ALD process, reaction gases are continuously introduced into the reaction chamber carrying the substrate. In order to increase the activity of the reaction gas, a PEALD (Plasma Enhanced Atomic Layer Deposition) process is generally used, which can further expand the kinds of reaction precursors compared to a general ALD process, and can reduce the temperature of the entire reaction chamber and increase the Deposition rate due to the higher activity of the Plasma.

Conventional PEALD apparatus includes a reaction chamber and a chamber assembly disposed at a top of the reaction chamber for applying rf power to the reaction chamber and delivering process gases. Specifically, fig. 1 is a cross-sectional view of a prior art chamber assembly. Referring to fig. 1, the chamber assembly includes an electrode plate 3, a uniform flow plate 4 and an air inlet nozzle 1, wherein the electrode plate 3 is electrically connected to a radio frequency power source 6 through a matcher 5. The electrode plate 3 and the uniform flow plate 4 form a uniform flow space, the air inlet nozzle 1 is arranged in the electrode plate 1, and the air inlet 2 of the air inlet nozzle 1 is communicated with the uniform flow space. And, a plurality of air outlets are provided in the flow equalizing plate 4, and the air outlets are respectively communicated with the flow equalizing space and the reaction chamber.

However, since the electrode plate 3 and the uniform flow plate 4 are made of conductive materials, the components simultaneously play a role of feeding the radio frequency energy and the uniform flow gas, which inevitably has the following problems in practical application:

since the electrode plate 3 and the uniform flow plate 4 are both applied with the radio frequency voltage, this may cause the gas in the gas outlet of the uniform flow plate 4 to be ionized to form plasma, which may easily cause hollow cathode discharge, thereby causing instability of the radio frequency system. In addition, the structural design of the air inlet nozzle 1 is easy to cause glow and ignition in a gas conveying pipeline butted with the air inlet nozzle 1. Both of these factors affect the stability of the plasma.

Disclosure of Invention

The invention aims to at least solve one technical problem in the prior art, and provides a chamber component and a reaction chamber, which can avoid the generation of hollow cathode discharge so as to improve the stability of plasma.

To achieve the object of the present invention, there is provided a chamber assembly including:

the electrode plate is electrically connected with the radio frequency source and is provided with an air inlet; and the number of the first and second groups,

the uniform flow component is made of insulating materials, a uniform flow space is formed between the uniform flow component and the electrode plate, the air inlet is communicated with the uniform flow space, a plurality of air outlets are formed in the uniform flow component, and the air outlets are respectively communicated with the uniform flow space and the reaction chamber.

Optionally, the upper surface of the electrode plate is a plane; the lower surface of the electrode plate is a dome-shaped curved surface, and the dome-shaped curved surface is recessed towards the upper surface.

Optionally, the flow equalizing part is divided into a circular central partition and an annular edge partition around the circular central partition; the diameter of the gas outlet in the circular central zone is smaller than the diameter of the gas outlet in the annular rim zone.

Optionally, the diameter of the air outlet in the circular central partition ranges from 1mm to 2.5 mm; the diameter of the air outlet in the annular edge partition ranges from 2.6mm to 5 mm.

Optionally, the flow equalizing part comprises a flow equalizing plate provided with the air outlet, and the thickness of the flow equalizing plate ranges from 2mm to 6 mm.

Optionally, the electrode plate structure further comprises a conveying pipeline and an insulating part, wherein the insulating part is located between the conveying pipeline and the electrode plate, an air inlet channel is arranged in the insulating part, and the air inlet channel is respectively communicated with the conveying pipeline and the air inlet.

Optionally, the air inlet channel includes a first through hole and a second through hole, wherein the second through hole is multiple and is disposed around the first through hole.

Optionally, the diameter of the first through hole ranges from 20mm to 30 mm; the diameter of the second through hole ranges from 1mm to 3 mm.

Optionally, the length of the insulating member in a direction perpendicular to the electrode plates is not less than 40 mm.

Optionally, the heating device further comprises a heating assembly, wherein the heating assembly is arranged on the top of the electrode plate and is arranged around the circumferential direction of the electrode plate.

Optionally, the shielding cover and the annular upper cover are grounded, wherein,

the annular upper cover is arranged at the top of the reaction chamber, and the uniform flow component is arranged on the inner side of the annular upper cover;

the shielding cover is arranged on the top of the annular upper cover and forms a closed space for closing the electrode plate and the heating assembly together with the annular upper cover.

As another technical solution, the present invention also provides a reaction chamber, including:

the invention provides the above chamber assembly;

the top of the cavity is provided with an opening, and an exhaust port is arranged on the cavity; the chamber assembly is arranged at the top of the cavity;

a confinement ring disposed in the cavity and forming an exhaust space between the confinement ring and the cavity, the exhaust space in communication with the exhaust port.

The invention has the following beneficial effects:

according to the chamber assembly provided by the invention, the electrode plate and the uniform flow component are arranged into two components, and the uniform flow component is made of an insulating material, so that the problem of hollow cathode discharge generated by the electrode plate can be avoided, and the stability of plasma can be improved.

According to the reaction chamber provided by the invention, hollow cathode discharge is avoided by adopting the chamber component provided by the invention, so that the stability of plasma can be improved.

Drawings

FIG. 1 is a cross-sectional view of a prior art chamber assembly;

FIG. 2 is a cross-sectional view of a chamber assembly provided by an embodiment of the present invention;

FIG. 3A is a top view of an insulator used in an embodiment of the present invention;

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

Fig. 4 is a cross-sectional view of a reaction chamber provided in an embodiment of the present invention.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the chamber assembly and the reaction chamber provided by the present invention will be described in detail below with reference to the accompanying drawings.

Referring to fig. 2, a chamber assembly according to an embodiment of the present invention includes an electrode plate 8 and a uniform flow component 9, wherein the electrode plate 8 is electrically connected to a radio frequency source, and a gas inlet 81 is disposed on the electrode plate 8 for delivering a process gas; the flow equalizing part 9 is made of insulating material and forms a flow equalizing space 10 together with the electrode plate 8, the gas inlet 81 is communicated with the flow equalizing space 10, and a plurality of gas outlets 911 are arranged on the flow equalizing part 9, and the gas outlets 911 are respectively communicated with the flow equalizing space 10 and a reaction chamber (not shown in the figure). The process gas enters the reaction chamber through the gas inlet 81, the uniform flow space 10 and the respective gas outlets 911 in sequence.

Because the electrode plate 8 and the uniform flow part 9 are arranged into two parts, and the uniform flow part 9 is made of insulating materials, the problem of hollow cathode discharge generated by the electrode plate can be avoided, and the stability of plasma can be improved. The insulating material is preferably Polyetheretherketone (PEEK), polyetherimide (ULTEM), or the like. The material has low probability (recombination rate) of returning the excited state of the plasma to the original state, thereby ensuring the stability of the plasma.

Preferably, the electrode plate 8 has different thicknesses corresponding to different regions of the reaction chamber, so that the electric field distribution in the reaction chamber tends to be uniform, thereby improving the plasma distribution uniformity. In the present embodiment, in the case where the electric field distribution is not uniform in the radial direction of the reaction chamber, for example, the electric field intensity in the center region of the reaction chamber is larger than that in the edge region. The upper surface 82 of the electrode plate 8 is a plane; the lower surface 83 of the electrode plate 8 is a dome-shaped curved surface that is recessed toward the upper surface 82. Thus, the thickness of the electrode plate 8 gradually increases from the center to the edge, and the impedance thereof gradually increases from the center to the edge, so that the difference of electric field distribution in the radial direction of the reaction chamber can be compensated, and the plasma distribution uniformity can be improved.

It should be noted that the lower surface 82 of the electrode plate 8 is not limited to the shape of the embodiment, and in practical applications, the lower surface may also take any other shape, such as a conical surface, a trapezoidal surface, and so on. Alternatively, the entire shape of the electrode plate 8 may be curved or bent. As long as the thickness of the electrode plate 8 is different corresponding to different regions of the reaction chamber. In addition, the thickness of the electrode plate 8 corresponding to different regions of the reaction chamber can be set according to the etching morphology of the wafer.

The larger the diameter of the gas outlet 911, the larger the flow rate of the gas; conversely, the smaller the diameter of the gas outlet 911, the smaller the flow rate of the gas. Based on this, the uniform flow component 9 is divided into a plurality of partitions, and the diameters of the gas outlets 911 in different partitions are different, so as to supplement the gas flow distribution difference in different areas of the corresponding reaction chamber, thereby improving the distribution uniformity of the plasma on the surface of the wafer, and further improving the film forming quality.

In the present embodiment, with respect to the difference in gas flow rate between the central region and the edge region of the reaction chamber, that is, the gas flow rate in the central region of the reaction chamber is greater than that in the edge region, two partitions are set, respectively, a circular central partition and an annular edge partition located around the circular central partition, and the diameter of the gas outlet 911 in the circular central partition is smaller than that in the annular edge partition, so that the difference in gas flow rate between the central region and the edge region of the reaction chamber can be compensated. Preferably, the diameter of the air outlet 911 in the circular central partition ranges from 1mm to 2.5 mm; the diameter of the gas outlet 911 in the annular edge partition ranges from 2.6mm to 5 mm.

Preferably, the diameter D1 of the circular central section is less than or equal to one third of the outer diameter D2 of the annular edge section.

Of course, in practical applications, more zones, such as 3 to 5 zones, may be further divided in the radial direction of the reaction chamber. Alternatively, any other manner of dividing the region may be adopted as long as improvement in uniformity of the air flow distribution can be achieved.

In the present embodiment, the flow equalizing member 9 comprises a flow equalizing plate 91 and a mounting ring 92 connected together, wherein the flow equalizing plate 91 is disposed at the top of the reaction chamber, and the gas outlet 911 is disposed on the flow equalizing plate 91; the mounting ring 92 is used to fixedly connect the flow homogenizing plate 91 to the reaction chamber. By integrating the flow equalizing plate 91 and the mounting ring 92, the structural stability can be improved. The thickness of the uniform flow plate 91 ranges from 2mm to 6 mm.

In this embodiment, the chamber assembly further includes a delivery pipe 13 and an insulating member 12, wherein an inlet end of the delivery pipe 13 is connected to the remote plasma source 141 for chamber cleaning, and an outlet end is connected to the insulating member 12. In addition, the delivery line 13 is also used to deliver process gas from the process gas delivery line 142. The insulating member 12 is located between the delivery pipe 13 and the electrode plate 8, and an intake passage is provided in the insulating member 12, the intake passage communicating with the delivery pipe 13 and the intake port 81, respectively. The process gas supplied from the gas source 14 enters the uniform flow space 10 through the delivery pipe 13, the gas inlet channel 121 and the gas inlet 81 in sequence.

By means of the insulating part 12, the conveying pipeline 13 and the electrode plate 8 can be electrically insulated, and meanwhile, the insulating distance between the conveying pipeline 13 and the electrode plate 8 is increased, so that the ignition risk can be reduced, and the system stability is improved. Preferably, the length of the insulating member 12 in the direction perpendicular to the electrode plate 8 is not less than 40mm, and preferably, the length ranges from 40mm to 60 mm.

Referring to fig. 3A, the air intake channel includes a plurality of first through holes 121 and a plurality of second through holes 122, wherein the plurality of second through holes 122 are disposed around the first through holes 121.

Optionally, the first through hole 121 is a through hole, and a diameter of the first through hole 121 ranges from 20mm to 30 mm. The second through hole 122 is a through hole, and the diameter of the second through hole 122 is smaller than the diameter of the first through hole 121. Since the diameter of the second through hole 122 is smaller, it can increase the pressure difference between the two ends of the insulating member 12, so that it can further avoid generating plasma in the through hole, and further affect the stability of the plasma in the reaction chamber. The diameter of the second through hole 122 ranges from 1mm to 3 mm. Of course, in practical applications, the second through hole 122 may also be a tapered hole.

In the present embodiment, as shown in fig. 3B, the insulating member 12 is hermetically connected to the conveying pipe 13 and the electrode plate 8, respectively, and chamfers are formed at both end portions of the air intake passage of the insulating member 12 (for example, chamfers B at both ends of the first through hole 121 shown in fig. 3B), and chamfered ends of the conveying pipe 13 and the air intake port 81, which are butted against the air intake passage, respectively. By performing the chamfering process, the risk of sparking can be further reduced.

Preferably, the chamber assembly further comprises a heating assembly 17, wherein the heating assembly 17 is arranged on the top of the electrode plate 8 and is arranged around the circumferential direction of the electrode plate 8; and, the heating member 17 includes a heating wire and an insulating layer covering the heating wire. By means of the insulating layer, the electrical insulation of the heating wire from the electrode plate 8 can be ensured, so that the risk of sparking can be further reduced. Of course, in practical application, an insulating medium heating wire can be used, and an insulating layer with better corrosion resistance and thermal conductivity is adopted to cover the heating wire. The material of the insulating layer is preferably aluminum. Alternatively, the heating element 17 may be adhesively secured to the electrode plate 8.

In the present embodiment, the heating assembly 17 includes a plurality of sections, and the plurality of sections are arranged at intervals along the circumferential direction of the electrode plate 8, so that the heating uniformity can be improved, and the process uniformity can be improved.

In this embodiment, the chamber assembly further comprises an rf electrode 11 and an rf source, wherein the rf electrode 11 is cylindrical and disposed on the top of the electrode plate 8 and located at the edge region of the electrode plate 8. The radio frequency source comprises a matcher 15 and a radio frequency power supply 16, and the matcher 15 is electrically connected with the radio frequency electrode 11.

In this embodiment, the chamber assembly further comprises a shielding cover 19 and an annular upper cover 18 which are both grounded, wherein the annular upper cover 18 is arranged at the top of the reaction chamber, and the uniform flow component 9 is arranged inside the annular upper cover 18; the shield 19 is disposed on top of the annular upper cover 18 and forms an enclosed space enclosing the rf electrode 11 together with the annular upper cover 18, thereby preventing rf leakage. Preferably, a beryllium copper spring is arranged between the contact surfaces of the shielding case 19 and the annular upper cover 18 to ensure the best shielding effect.

In the prior art, the chamber assembly includes multiple dielectric layers stacked from the inside to the outside, which requires the rf electrode to pass through the multiple dielectric layers to make contact with the electrode plate. For this reason, by means of the shield 19, the number of dielectric layers can be reduced, so that the radio-frequency electrode 11 is in direct contact with the electrode plate without passing through the dielectric layers. Moreover, the reduction of the number of the dielectric layers avoids the phenomenon of interlayer ignition, thereby improving the stability of the system.

The top wall of the shield case 19 is flat, and the utilization rate of the radio frequency power can be improved by setting the distance D3 between the top wall of the shield case 19 and the electrode plate 8. The greater the separation D3, the greater the utilization of the rf power. Preferably, the distance D3 is in the range of 40mm to 100 mm.

In summary, the chamber assembly provided by the embodiments of the present invention has the following advantages:

firstly, because the uniform flow component 9 is made of insulating materials, the problem of hollow cathode discharge generated by the electrode plate can be avoided, and the stability of plasma can be improved.

Secondly, the electrode plate 8 has different thicknesses corresponding to different areas of the reaction chamber, so that the electric field distribution in the reaction chamber tends to be uniform, and the plasma distribution uniformity can be improved.

Thirdly, with the help of insulating part 12, can be with transfer piping 13 and electrode board 8 electrical insulation, increase the insulating distance between the two simultaneously to can reduce the risk of striking sparks, improve system stability.

Fourthly, the heating assembly 17 includes a heating wire and an insulating layer covering the heating wire. By means of the insulating layer, the electrical insulation of the heating wire from the electrode plate 8 can be ensured, so that the risk of sparking can be further reduced.

Fifthly, by means of the shielding cover 19, the number of the dielectric layers can be reduced, so that the radio frequency electrode 11 is directly contacted with the electrode plate without penetrating through the dielectric layers. Moreover, the reduction of the number of the dielectric layers avoids the phenomenon of interlayer ignition, thereby improving the stability of the system.

Sixthly, the utilization rate of the radio frequency power can be improved by setting the distance D3 between the top wall of the shielding case 19 and the electrode plate 8. The greater the separation D3, the greater the utilization of the rf power.

As another technical solution, referring to fig. 4, an embodiment of the present invention provides a reaction chamber including the chamber assembly, the cavity 20 and the confinement ring 21 provided in the embodiment of the present invention.

Wherein, the top of the cavity 20 has an opening, and an exhaust port 201 is disposed on the cavity 20. The chamber assembly is disposed at the top of the chamber body 10. A confinement ring 21 is disposed in the chamber 20 for confining a distribution area of the plasma 25. An exhaust space 22 is formed between the confinement ring 21 and the chamber 20, the exhaust space 22 communicates with the exhaust port 201, and the residual gas is exhausted through the exhaust space 22 and the exhaust port 201 in this order. The flow equalizing member 9 is disposed on the top of the confinement rings 21 and closes the top openings of the confinement rings 21, and the gas flowing out of the gas outlets 911 enters the confinement rings 21. A susceptor 23 is disposed within the chamber 20 for carrying wafers, and the susceptor 23 is elevatable and closes the bottom opening of the confinement rings 21 when the susceptor 23 is raised to the process position as shown in fig. 4.

In practical applications, to ensure that the process gas enters the exhaust space 223 less, the confinement ring 21 may be fixed by crimping.

In addition, a heating rod 24 is disposed in the chamber 20 to ensure a constant temperature in the chamber. The heating rods 24 may be plural and symmetrically distributed around the axial direction of the chamber to uniformly heat the chamber 20.

In practical applications, the reaction chamber may be an Atomic Layer Deposition (ALD) reaction chamber, a Plasma Enhanced Chemical Vapor Deposition (PECVD) reaction chamber, or the like.

According to the reaction chamber provided by the embodiment of the invention, the chamber assembly provided by the embodiment of the invention is adopted, so that not only can the stability of plasma be improved, but also the distribution uniformity of the plasma can be improved.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.

Claims

1. A chamber assembly, comprising:

the electrode plate is electrically connected with the radio frequency source and is provided with an air inlet; the upper surface of the electrode plate is a plane; the lower surface of the electrode plate is a dome-shaped curved surface, and the dome-shaped curved surface is recessed towards the upper surface; and the number of the first and second groups,

2. The chamber assembly of claim 1, wherein the flow homogenizing member is divided into a circular central zone and an annular edge zone located around the circular central zone; the diameter of the gas outlet in the circular central zone is smaller than the diameter of the gas outlet in the annular rim zone.

3. The chamber assembly of claim 2, wherein the diameter of the gas outlet in the circular central section ranges from 1mm to 2.5 mm; the diameter of the air outlet in the annular edge partition ranges from 2.6mm to 5 mm.

4. The chamber assembly of claim 3, wherein the flow-equalizing member comprises a flow-equalizing plate having the gas outlet, and a thickness of the flow-equalizing plate ranges from 2mm to 6 mm.

5. The chamber assembly of claim 1, further comprising a transfer line and an insulating member, wherein the insulating member is located between the transfer line and the electrode plate, and wherein an inlet passage is provided in the insulating member, the inlet passage communicating with the transfer line and the inlet port, respectively.

6. The chamber assembly of claim 5, wherein the gas inlet passage comprises a first through hole and a second through hole, wherein the second through hole is plural and is disposed around the first through hole.

7. The chamber assembly of claim 6, wherein the diameter of the first through hole ranges from 20mm to 30 mm; the diameter of the second through hole ranges from 1mm to 3 mm.

8. The chamber assembly of claim 5, wherein a length of the insulating member in a direction perpendicular to the electrode plates is not less than 40 mm.

9. The chamber assembly of claim 1, further comprising a heating assembly disposed on top of the electrode plate and disposed around a circumferential direction of the electrode plate.

10. The chamber assembly of claim 9, further comprising a shield and an annular upper cover that are both grounded, wherein,

11. A reaction chamber, comprising:

the chamber assembly of any one of claims 1-10;