Wafer cleaning device

Abstract

The utility model provides a wafer cleaning device, which comprises a first shell, a cover body, a base station and a plurality of exhaust pipelines, and is characterized in that the first shell and the cover body jointly define a cleaning cavity; the base station is positioned at the bottom of the first shell and is used for bearing a wafer; the plurality of air extraction pipelines are arranged below the base station, each air extraction pipeline is provided with an air extraction opening, and the plurality of air extraction openings are uniformly distributed around the base station. In the air exhaust process, the suction forces generated by the plurality of air exhaust pipelines below the wafer are basically the same, so that the condition of non-uniform ion flow distribution when the plasma gas bombards the surface of the wafer is avoided, the wafer is etched and cleaned more uniformly, and the process yield is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor manufacturing, and in particular to a wafer cleaning device. Background Art

[0002] In the semiconductor process, keeping the wafer surface clean is a key condition for chip manufacturing and has a great impact on the chip yield. To ensure the chip yield, the wafer needs to be cleaned in almost every process to remove contaminants on the wafer.

[0003] To perform plasma cleaning on wafers, integrated circuits are placed in a plasma chamber, and then a pump expel most of the air from the chamber; electromagnetic energy (e.g., radio frequency) is applied to an injected gas, such as argon, to excite the injected gas to a plasma state; the plasma releases ions, which bombard the wafer surface to remove contaminants; the contaminants are etched off the substrate and most of them are pumped out of the chamber. However, in existing wafer cleaning devices, the pump is usually located in a corner of the chamber. During the process, the pump will perform vacuum extraction, but the suction it generates will affect the distribution of ions in the chamber, resulting in a faster etching speed on the side of the wafer close to the pump, which will ultimately affect the overall cleaning effect of the wafer and affect the process yield. Utility Model Content

[0004] In view of the shortcomings of the prior art described above, the present application provides a wafer cleaning device, comprising a first shell, a cover, a base and a plurality of exhaust pipes, wherein the first shell and the cover together enclose a cleaning chamber; the base is located at the bottom of the first shell, and is used to carry the wafer; a plurality of exhaust pipes are arranged below the base, each exhaust pipe has an exhaust port, and the plurality of exhaust ports are evenly arranged around the base. During the exhaust process, the suction force generated by the plurality of exhaust pipes below the wafer is basically the same, thereby avoiding the uneven distribution of ion flow when the plasma gas bombards the wafer surface, making the wafer etched and cleaned more evenly, and improving the process yield.

[0005] To achieve the above objectives and other related objectives, the present application provides a wafer cleaning device, comprising:

[0006] a first shell, wherein the first shell has an opening facing upward;

[0007] A cover body, located above the first shell, with an opening of the cover body facing the first shell, and the cover body and the first shell together enclose a cleaning chamber;

[0008] A base, located at the bottom of the first shell, used for carrying the wafer;

[0009] A plurality of air extraction pipelines are arranged below the base, each of the air extraction pipelines has an air extraction port, and the plurality of air extraction ports are evenly arranged around the base;

[0010] A plasma generating device is used to generate plasma in the cleaning chamber.

[0011] Optionally, a second shell is further included, wherein the second shell is located above the first shell, an opening of the second shell faces the first shell, and the second shell surrounds the cover.

[0012] Optionally, a gas supplier is further included for supplying processing gas to the cleaning chamber.

[0013] Optionally, an air inlet pipeline is further included, one end of which is connected to the cover body, and the other end of which is connected to the gas supplier to connect the gas supplier and the cleaning chamber.

[0014] Optionally, the number of the exhaust pipelines is at least four.

[0015] Optionally, the plasma generating device includes an induction coil, and the induction coil is located between the second shell and the cover body and is arranged around the cover body.

[0016] Optionally, the plasma generating device further includes an excitation power supply, and the excitation power supply is electrically connected to the induction coil.

[0017] Optionally, the plasma generating device further includes a bias power supply, and the bias power supply is electrically connected to the base.

[0018] Optionally, the excitation power supply and the bias power supply are both radio frequency power supplies.

[0019] Optionally, an isolation ring is further included, and the isolation ring is arranged between the base and the bottom surface of the first shell to insulate the base from the first shell.

[0020] The wafer cleaning device provided in this application has at least the following beneficial effects:

[0021] The wafer cleaning device provided by the present application includes a first shell, a cover, a base and a plurality of exhaust pipes, wherein the first shell and the cover together enclose a cleaning chamber; the base is located at the bottom of the first shell and is used to carry the wafer; a plurality of exhaust pipes are arranged below the base, each exhaust pipe has an exhaust port, and the plurality of exhaust ports are evenly arranged around the base. During the exhaust process, the suction force generated by the plurality of exhaust pipes below the wafer is basically the same, thereby avoiding the uneven distribution of ion flow when the plasma gas bombards the wafer surface, making the wafer etched and cleaned more evenly and improving the process yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Shown is a schematic structural diagram of a wafer cleaning device provided in an embodiment.

[0023] Figure 2 A top view showing the arrangement of exhaust pipes around a base platform in a wafer cleaning device provided in an embodiment is shown.

[0024] Component number description

[0025] 11. First Shell

[0026] 12 Second shell

[0027] 20 Cover

[0028] 30 abutment

[0029] 40 Exhaust pipeline

[0030] 400 Air extraction port

[0031] 50 Gas Supply

[0032] 60 Intake pipe

[0033] 70 Isolation ring

[0034] 81 Induction coil

[0035] 82 Excitation power supply

[0036] 83 Bias power supply

[0037] 90 Vacuum Pump

[0038] 100 Cleaning chamber

[0039] 200 Wafer DETAILED DESCRIPTION

[0040] The following describes the implementation of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application.

[0041] It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present application in a schematic manner. Although the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation, the form, quantity, positional relationship and proportion of each component in actual implementation can be changed at will under the premise of realizing the technical solution of this party, and the component layout form may also be more complicated.

[0042] Example

[0043] This embodiment provides a wafer cleaning device, such as Figure 1 As shown, it includes a first shell 11, a cover body 20, a base 30 and a plurality of exhaust pipes 40, wherein the cover body 20 and the first shell 11 together form a cleaning chamber 100, the base 30 is located at the bottom of the first shell 11, and the plurality of exhaust pipes 40 are arranged below the base 30.

[0044] like Figure 1 As shown, the first shell 11 has an opening facing upward; the cover 20 is located above the first shell 11, and the opening of the cover 20 faces the first shell 11, and the cover 20 and the first shell 11 together enclose a cleaning chamber 100. As an example, the first shell 11 can be made of metal, such as aluminum. In this embodiment, the cover 20 is a hemispherical structure; the cover 20 is made of a dielectric material, such as glass, quartz, etc.

[0045] like Figure 1 As shown, the base 30 is located at the bottom of the first housing 11 and is used to carry the wafer 200. In this embodiment, the base 30 includes a base made of metal, an electrostatic chuck made of a dielectric material, and a bonding layer for bonding the two. In other optional embodiments, the base 30 may have other structures, such as only having a base and an electrostatic chuck made of metal, and the electrostatic chuck is bonded to the upper surface of the base by spraying technology; or, the base 30 may only include a metal base.

[0046] like Figure 1 As shown, an isolation ring 70 is further disposed between the base 30 and the bottom surface of the first shell 11 to insulate the base 30 from the first shell 11 .

[0047] like Figure 1 As shown, the wafer cleaning device further includes a second housing 12, which is located above the first housing 11, with an opening facing the first housing 11, and surrounds the cover 20. As an example, the second housing 12 may be made of metal, such as aluminum.

[0048] like Figure 1 As shown, the wafer cleaning apparatus further comprises a gas supplier 50 for supplying a processing gas to the cleaning chamber. As an example, the processing gas may include one or more of hydrogen, helium, argon or the like; in this embodiment, the processing gas includes a mixture of hydrogen and helium, wherein hydrogen accounts for about 5%.

[0049] like Figure 1As shown, the wafer cleaning device also includes an air inlet pipeline 60, one end of which is connected to the cover body 20, and the other end is connected to the gas supplier 50, thereby connecting the gas supplier 50 and the cleaning chamber, so that the processing gas enters the cleaning chamber through the air inlet pipeline 60.

[0050] like Figure 1 As shown, the wafer cleaning device is also provided with a plasma generating device, including an induction coil 81, an excitation power supply 82 and a bias power supply 83, wherein the excitation power supply 82 is electrically connected to the induction coil 81, and the bias power supply 83 is electrically connected to the base 30. It should be noted that this embodiment is described by taking an inductively coupled plasma etching cleaning device as an example, and those skilled in the art should understand that the present invention is not limited thereto, and is also applicable to various plasma processing devices, such as a capacitively coupled plasma etching cleaning device, etc.

[0051] like Figure 1 As shown, the induction coil 81 is located between the second housing 12 and the cover 20 and is disposed around the cover 20; an excitation power source 82 is coupled to the induction coil 81 to generate plasma in the cleaning chamber 100. In other optional embodiments, the plasma may be remotely generated by, for example, a remote plasma source or the like, and flow into the cleaning chamber 100.

[0052] As an example, the excitation power source 82 may be a radio frequency power source or a direct current power source. In the present embodiment, the excitation power source 82 is a radio frequency power source, for example, a radio frequency ICP source or a radio frequency CCP source, with a frequency between 20 kHz and 60 MHz. Since the energy of the radio frequency power source is greater than the energy of the direct current power source, the density of the plasma generated by the radio frequency power source is greater than the density of the plasma generated by the direct current power source, and the contaminants on the surface of the wafer 200 can be better removed.

[0053] like Figure 1 As shown, the bias power supply 83 is coupled to the base 30, and the bias power supply 83 can guide the plasma to the surface of the wafer 200, and control the ion flux flowing to the surface of the wafer 200, which helps to more effectively remove pollutants on the surface of the wafer 200 and improve the cleaning ability of the wafer cleaning device. As an example, the bias power supply 83 can be a radio frequency power supply or a direct current power supply. In this embodiment, the bias power supply 83 is a radio frequency power supply, for example, it can be a radio frequency ICP source or a radio frequency CCP source, and the RF energy supplied by the bias power supply 83 can have a frequency of about 10 MHz or higher; in some embodiments, the RF energy supplied by the bias power supply 83 can have a frequency of about 13.56 MHz.

[0054] Combination Figure 1 and Figure 2As shown, a plurality of exhaust pipes 40 are arranged below the base 30, one end of the exhaust pipes 40 is an exhaust port 400, and the plurality of exhaust ports 400 are evenly arranged around the base 30, and the other end of the exhaust pipes 40 is connected to the vacuum pump 90, and the exhaust pipes 40 are used to extract the exhaust gas after cleaning out of the cleaning chamber 100. As an example, the number of the exhaust pipes 40 is at least four, and the specific value thereof needs to be set according to the actual production situation; in this embodiment, the number of the exhaust pipes 40 is six. The plurality of exhaust pipes 40 are evenly arranged around the base 30, and during the exhaust process, the suction force generated by the plurality of exhaust pipes 40 below the wafer 200 is substantially the same, thereby avoiding the uneven distribution of ion flow when the plasma gas bombards the surface of the wafer 200, so that the wafer 200 is etched and cleaned more evenly, so as to achieve a better process effect.

[0055] The working principle of the wafer cleaning device provided in this embodiment is as follows:

[0056] First, the wafer 200 is placed on the surface of the base 30, and the cleaning chamber 100 is evacuated by using the vacuum pump 90 and the exhaust pipe 40; then, the processing gas is introduced into the cleaning chamber 100 by using the gas supplier 50 and the air inlet pipe 60; then, the radio frequency power is transmitted to the cover 20 and the base 30 by using the plasma generator, so that an electric field is generated in the cleaning chamber 100, and the electric field accelerates a small amount of electrons existing inside the cleaning chamber 100, causing them to collide with the gas molecules of the input processing gas, and the collision causes the ionization of the processing gas and the excitation of the plasma, thereby generating plasma in the cleaning chamber 100, and the neutral gas molecules of the processing gas lose their electrons when subjected to these strong electric fields, leaving positively charged ions, and the positively charged ions are accelerated toward the direction of the base 30, and combine with the substances on the surface of the wafer 200, thereby cleaning the surface of the wafer 200; during the cleaning process, the exhaust gas is extracted from the cleaning chamber 100 through the exhaust pipe 40.

[0057] The wafer cleaning device provided in this embodiment includes a first shell, a cover, a base and a plurality of exhaust pipes, wherein the first shell and the cover together enclose a cleaning chamber; the base is located at the bottom of the first shell and is used to carry the wafer; a plurality of exhaust pipes are arranged below the base, each exhaust pipe has an exhaust port, and the plurality of exhaust ports are evenly arranged around the base. During the exhaust process, the suction force generated by the plurality of exhaust pipes below the wafer is basically the same, thereby avoiding the uneven distribution of ion flow when the plasma gas bombards the wafer surface, making the wafer etched and cleaned more evenly and improving the process yield.

[0058] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A wafer cleaning device, characterized in that: include: a first shell, wherein the first shell has an opening facing upward; A cover body, located above the first shell, with an opening of the cover body facing the first shell, and the cover body and the first shell together enclose a cleaning chamber; A base, located at the bottom of the first shell, used for carrying the wafer; A plurality of air extraction pipelines are arranged below the base, each of the air extraction pipelines has an air extraction port, and the plurality of air extraction ports are evenly arranged around the base; A plasma generating device is used to generate plasma in the cleaning chamber.

2. The wafer cleaning device according to claim 1, characterized in that: It also includes a second shell, which is located above the first shell, has an opening facing the first shell, and surrounds the cover.

3. The wafer cleaning device according to claim 1, characterized in that: A gas supplier is also included for supplying a processing gas to the cleaning chamber.

4. The wafer cleaning device according to claim 3, characterized in that: It also includes an air inlet pipeline, one end of which is connected to the cover body, and the other end of which is connected to the gas supplier to connect the gas supplier and the cleaning chamber.

5. The wafer cleaning device according to claim 1, characterized in that: The number of the air extraction pipelines is at least four.

6. The wafer cleaning device according to claim 2, characterized in that: The plasma generating device comprises an induction coil, and the induction coil is located between the second shell and the cover body and is arranged around the cover body.

7. The wafer cleaning device according to claim 6, characterized in that: The plasma generating device further comprises an excitation power supply, and the excitation power supply is electrically connected to the induction coil.

8. The wafer cleaning device according to claim 7, characterized in that: The plasma generating device further includes a bias power supply, and the bias power supply is electrically connected to the base.

9. The wafer cleaning device according to claim 8, characterized in that: The excitation power supply and the bias power supply are both radio frequency power supplies.

10. The wafer cleaning device according to claim 1, characterized in that: It also includes an isolation ring, which is arranged between the base and the bottom surface of the first shell to insulate the base from the first shell.

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