Method for cleaning rate improvement of multiple rpsc pecvd system

Abstract

Embodiments of the present disclosure generally relate to a method of cleaning a chemical vapor deposition chamber. The method includes initiating flow of a cleaning gas to a central remote plasma source (RPS) reactor in a processing chamber. The method includes initiating a flow of a cleaning gas to a four corner RPS reactor in a processing chamber. The method also includes flowing a cleaning gas to the central RPS reactor and the four corner RPS reactors. The method further includes stopping flowing the cleaning gas to the center RPS reactor and stopping flowing the cleaning gas to the four corner RPS reactors.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to chemical vapor deposition chambers and methods for cleaning the same. More specifically, embodiments described herein relate to a method of chemical vapor deposition, a method of cleaning a chemical vapor deposition chamber by controlling an independent remote plasma source, a non-transitory storage medium having stored instructions for performing chemical vapor deposition operations, a non-transitory storage medium having stored instructions for performing operations for cleaning a chemical vapor deposition chamber, and a chemical vapor deposition chamber. Background Art

[0002] Plasma enhanced chemical vapor deposition (PECVD) is generally used to deposit thin films on substrates such as semiconductor substrates, solar panel substrates, organic light emitting diode (OLED) substrates, and liquid crystal display (LCD) substrates. Such substrates can be quite large and substantially rectangular. PECVD is generally accomplished by introducing precursor gases into a vacuum chamber with a substrate disposed on a substrate support. The precursor gases are delivered to the substrate through a gas distribution assembly in the chamber.

[0003] During chemical vapor deposition, deposited material may form on components of the chamber, such as the gas distribution assembly and the inner sidewalls of the chamber. This deposited material may flake off during subsequent processing and generate contaminant particles that can damage substrates in the chamber. Therefore, periodic chamber cleaning is used.

[0004] Current methods of cleaning PECVD chambers are inefficient. This inefficiency can lead to increased process downtime and waste of cleaning gases. Thus, there is a need in the art for improved cleaning equipment and methods. Summary of the invention

[0005] Embodiments of the present disclosure generally relate to chemical vapor deposition chambers and methods for cleaning the same. More specifically, embodiments described herein relate to a method of chemical vapor deposition, a method of cleaning a chemical vapor deposition chamber by controlling an independent remote plasma source, a non-transitory storage medium having stored instructions for performing chemical vapor deposition operations, a non-transitory storage medium having stored instructions for performing operations for cleaning a chemical vapor deposition chamber, and a chemical vapor deposition chamber.

[0006] In one or more embodiments, a method of cleaning a chemical vapor deposition chamber. The method includes starting to flow a cleaning gas to a central remote plasma source (RPS) reactor in the processing chamber. The method also includes starting to flow a cleaning gas to four corner RPS reactors in the processing chamber. The method includes flowing a cleaning gas to the central RPS reactor and the four corner RPS reactors. The method further includes stopping flowing a cleaning gas to the central RPS reactor and stopping flowing a cleaning gas to the four corner RPS reactors.

[0007] In one or more embodiments, a non-transitory storage medium having stored instructions, when executed by a processor, the instructions will cause the processor to perform operations for cleaning a chemical vapor deposition chamber. The instructions include starting to flow a cleaning gas to a central remote plasma source (RPS) reactor in a processing chamber. The instructions include starting to flow a cleaning gas to four corner RPS reactors in the processing chamber. The instructions also include flowing a cleaning gas to the central RPS reactor and the four corner RPS reactors. The instructions further include stopping flowing a cleaning gas to the central RPS reactor and stopping flowing a cleaning gas to the four corner RPS reactors.

[0008] In one or more embodiments, a chemical vapor deposition chamber. The chemical vapor deposition chamber includes a chamber body and a chamber lid and a central remote plasma source (RPS) reactor fluidly coupled to the center of the chamber lid. The chamber also includes four corner RPS reactors, each corner RPS reactor fluidly coupled to a corresponding corner of the chamber lid. The chamber includes a common valve fluidly connected to the four corner RPS reactors. The chamber further includes a central valve fluidly connected to the central RPS reactor and a clean gas supply fluidly connected to the common valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to be able to understand in detail the manner in which the above-mentioned features of the present disclosure are used, a more particular description of the present disclosure briefly summarized above may be made with reference to embodiments, some of which are shown in the accompanying drawings. However, it will be noted that the accompanying drawings only illustrate common embodiments of the present disclosure and are therefore not to be considered as limiting its scope, as the present disclosure may admit to other equally effective embodiments.

[0010] Figure 1 is a cross-sectional view of a chemical vapor deposition chamber according to one or more embodiments.

[0011] FIG. 2A to FIG. 2B is a schematic layout of plumbing for remote plasma source cleaning (RPSC) of a chemical vapor deposition chamber according to one or more embodiments.

[0012] Figure 3A is a schematic block diagram of a method of cleaning a chemical vapor deposition chamber according to one or more embodiments.

[0013] Figure 3B is a schematic block diagram of a method of cleaning a chemical vapor deposition chamber according to one or more embodiments.

[0014] Figure 4 is a graph showing the effect of cleaning gas flow rate on the cleaning rate of a chemical vapor deposition chamber.

[0015] Figure 5 is a graph showing the effect of the length of the first cleaning process on the cleaning rate of a chemical vapor deposition chamber. DETAILED DESCRIPTION

[0016] Embodiments of the present disclosure generally relate to chemical vapor deposition chambers and methods for cleaning the same. More specifically, embodiments described herein relate to a method of chemical vapor deposition, a method of cleaning a chemical vapor deposition chamber by controlling an independent remote plasma source, a non-transitory storage medium having stored instructions for performing chemical vapor deposition operations, a non-transitory storage medium having stored instructions for performing operations for cleaning a chemical vapor deposition chamber, and a chemical vapor deposition chamber.

[0017] Figure 1 1 is a schematic cross-sectional view of a processing chamber 100, such as a plasma enhanced chemical vapor deposition (PECVD) chamber, according to one embodiment. The processing chamber 100 can be used to deposit one or more films onto a substrate 140. The processing chamber 100 can be used to process one or more substrates 140, such as semiconductor substrates, flat panel display substrates, and solar panel substrates, among other substrates.

[0018] The processing chamber 100 generally includes a sidewall 102, a bottom 104, and a showerhead 110 that define a processing space 106. A substrate support (or pedestal) 130 is disposed in the processing space 106. The substrate support 130 includes a substrate receiving surface 132 for supporting a substrate 140. The processing space 106 is accessed through an opening 108 formed through the sidewall 102 so that the substrate 140 can be moved in and out of the processing chamber 100 when the substrate support 130 is in a lowered position. One or more rods 134 can be coupled to a lift system 136 to raise and lower the substrate support 130. As shown in FIG. Figure 11, the substrate 140 is in a lowered position where the substrate 140 can be transferred in and out of the processing chamber 100. The substrate 140 can be raised to a processing position, not shown, for processing. When the substrate support 130 is raised to the processing position, the spacing between the top surface of the substrate 140 disposed on the substrate receiving surface 132 and the showerhead 110 can be between about 400 mils and about 1,200 mils. In one embodiment, the spacing can be between about 400 mils and about 800 mils.

[0019] Lift pins 138 are movably disposed through the substrate support 130 to space the substrate 140 from the substrate receiving surface 132 for facilitating robotic transfer of the substrate. The substrate support 130 may also include heating and / or cooling elements 139 to maintain the substrate support 130 at a predetermined temperature. The substrate support 130 may also include RF return straps 131 to provide an RF return path at the periphery of the substrate support 130.

[0020] The showerhead 110 may be coupled to the backing plate 112 at its perimeter via hangers 114. The showerhead 110 may also be coupled to the backing plate 112 via one or more coupling supports 160 to help reduce sag and / or control the straightness / curvature of the showerhead 110.

[0021] The gas source 120 may be fluidly coupled to the backing plate 112 to provide a process gas to a substrate 140 disposed on the substrate receiving surface 132 through a gas outlet 142 in the backing plate 112 and through a gas channel 111 in the showerhead 110. A vacuum pump 109 may be coupled to the processing chamber 100 to control the pressure within the processing volume 106. An RF power source 122 is coupled to the backing plate 112 and / or the showerhead 110 to provide RF power to the showerhead 110. The RF power generates an electric field between the showerhead 110 and the substrate support 130 so that a plasma may be generated from the gas between the showerhead 110 and the substrate support 130. Various frequencies may be used, such as between about 0.3 MHz and about 200 MHz. In one embodiment, the RF power may be provided at a frequency of 13.56 MHz.

[0022] The frame 133 can be positioned adjacent to a perimeter region of the substrate 140, in contact with the substrate 140, or spaced apart from the substrate 140. In some embodiments, the frame 133 can be configured to be positioned below the substrate 140. In other embodiments, the frame 133 can be configured to be positioned above the substrate 140. The frame 133 can be a shielded frame, a non-contact frame (e.g., the frame does not contact the substrate when positioned on the substrate support 130), a floating frame, a removable frame, a confinement ring, a flow control structure, or other suitable structure that can be positioned adjacent to a perimeter of the substrate 140.

[0023] During the cleaning process, the frame 133 may rest on the frame support 162. The substrate receiving surface 132 may also be raised to a level that touches the frame 133 during cleaning without lifting the frame 133 from the frame support 162.

[0024] The processing chamber 100 includes a plurality of remote plasma sources, such as five (three 124A-124C are shown). A first remote plasma source 124A (such as an inductively coupled remote plasma source) may also be coupled between the gas source 120 and the backing plate 112 at a central location of the backing plate. A second remote plasma source 124B may be located near a corner of the backing plate. For example, if the backing plate is divided into a plurality of quadrants in a plan view, the second remote plasma source 124B may be coupled to the backing plate in one of the quadrants. Similarly, a third remote plasma source 124C may be located in another quadrant, and two other remote plasma sources may each be disposed in the remaining quadrants accordingly. (Note that in Figure 2A and Figure 2B 106). Between processing substrates, a cleaning gas may be provided to the remote plasma source 124 so that a remote plasma is generated and provided into the processing space 106 to clean chamber components. While in the processing space 106, the cleaning gas may be further excited by power applied from the RF power source 122 to the showerhead 110. Suitable cleaning gases include, but are not limited to, NF3, F2, and SF6. The cleaning gas may be used alone or, as shown on page 2 of the appendix, may be used in combination with an inert gas. Available inert gases include, but are not limited to, argon and nitrogen.

[0025] Figure 2A 2 is an embodiment of a remote plasma source cleaning (RPSC) system. Cleaning gas is supplied to a common valve 201. The common valve 201 may be a single piece of equipment distributed to the five RPS reactors 240, 250, or the common valve 201 may be a series of valves and pipes that distribute the cleaning gas. Figure 2AAs shown, a single conduit may lead to multiple corner RPS reactors 240. In another embodiment, the corner RPS reactor 240 may have a dedicated clean gas supply conduit. In one embodiment, a common valve 201 evenly distributes the clean gas to the five RPS reactors 240, 250. In one embodiment, the four corners of the processing chamber 100 have corner RPS reactors 240. The center of the processing chamber 100 also has a central RPS reactor 250. In one embodiment, there is no difference between the RPS reactors 240, 250 except for the position within the PECVD system. For example, in one embodiment, each of the RPS reactors 240, 250 receives an equal flow rate of clean gas. Each of the RPS reactors 240, 250 may operate for the same different amount of time during the cleaning operation. Each of the RPS reactors 240, 250 may have an open valve 210, 220 on the conduit leading to the inlet. The closing valve 230 may be located after the break in the conduit leading to the central RPS reactor 250.

[0026] Figure 2B is an embodiment of an RPSC system according to another embodiment. This configuration of the RPSC system includes a pipeline to the central RPS reactor 250, which is not connected to the common valve 201. The central RPS reactor 250 is connected to a gas supplier through a valve 220. The central RPS reactor can be connected to the same clean gas supplier as the common valve 201 or to a second clean gas supplier that is not connected to the common valve 201.

[0027] The clean gas flow to the center RPS reactor is independently controlled relative to the corner RPS reactors 240, which are each controlled together (separately from the center RPS reactor 250). The clean gas supply to the four corner RPS reactors 240 can be supplied through a common valve 201, and in one example, the common valve 201 can provide equal flow rates to each corner RPS reactor 240. The pipeline connecting the common valve 201 to the corner RPS reactors 240 can have an open valve to allow the clean gas to flow to the corner RPS reactors 240. The shut-off valve 230 can be located on the pipeline from the common valve 201, which leads to a location near the center RPS reactor. The pipeline after the shut-off valve 230 can also be equipped with a blind flange to prevent clean gas leakage.

[0028] Figure 3A is a schematic block diagram of a method 300a for cleaning a processing chamber 100 according to one or more embodiments. The method 300a may utilize Figure 2A RPSC system.

[0029] In operation 310a, the flow of clean gas to all five RPS reactors 240, 250 begins simultaneously. During operation 320a, clean gas is directed to the five RPS reactors 240, 250. To increase or decrease the flow of clean gas, the flow of clean gas to all five RPS reactors 240, 250 is increased or decreased. In one or more embodiments, the flow of clean gas during operation 320a is constant. In one or more embodiments, the flow of clean gas during operation 320a is ramped up, ramped down, or operated in any other non-constant manner. In one or more embodiments, operation 310a is operated by opening valves 210, 220. In one or more embodiments, operation 310a is operated by opening common valve 201.

[0030] In operation 330a, flow to all RPS reactors 240, 250 is stopped simultaneously. Operation 330a may occur when the RPS reactors 240, 250 are completely cleaned, when it is determined that the RPS reactors 240, 250 are sufficiently cleaned, after a set period of time, at the request of an operator, or at any other time. In one or more embodiments, operation 310a is operated by closing valves 210, 220. In one or more embodiments, operation 310a is operated by closing common valve 201.

[0031] Figure 3B is a schematic block diagram of a method 300b of cleaning a processing chamber 100 according to one or more embodiments.

[0032] In operation 310b, the flow of clean gas to the center RPS reactor 250 is started. In one or more embodiments, operation 310b is operated by opening valve 220. In operation 312b, the flow of clean gas to the corner RPS reactor 240 is started. In one or more embodiments, operation 312b is operated by opening valve 210 or common valve 201. In one or more embodiments, operations 310b and 312b are started simultaneously. In one or more embodiments, operation 310b is started before operation 312b. In one or more embodiments, operation 312b is started before operation 310b.

[0033] In operation 320b, the clean gas flows to the central RPS reactor 250. In one or more embodiments, the flow of the clean gas during operation 320b is constant. In one or more embodiments, the flow of the clean gas during operation 320b is ramped up, ramped down, or operated in any other non-constant manner.

[0034] In operation 322b, the clean gas flows to the corner RPS reactor 240. In one or more embodiments, the flow of the clean gas during operation 322b is constant. In one or more embodiments, the flow of the clean gas during operation 322b is ramped up, ramped down, or operated in any other non-constant manner.

[0035] In operation 330b, flow to the central RPS reactor 250 is stopped. Operation 330b may occur when the central RPS reactor 250 is completely cleaned, when it is determined that the central RPS reactor 250 is sufficiently cleaned, after a set period of time, at the request of an operator, or at any other time. For example, operation 330b may begin after 0 seconds to 40 seconds of operation 320b, for example, after 10 seconds to 20 seconds of operation 320b.

[0036] In one or more embodiments, after operation 330b, the flow of the clean gas toward the corner RPS reactor 240 is maintained, increased, or decreased.

[0037] In one or more embodiments, operations 320b, 322b, and 330b are run as a dual process cleaning operation. In a first process, operations 320b and 322b are run at a first rate. In a second process, the flow of the cleaning gas to the center RPS reactor 250 is stopped in operation 322b, and the flow of the cleaning gas to the corner RPS reactor 240 is maintained or increased.

[0038] In operation 332b, flow is stopped to corner RPS reactor 240. Operation 330b may occur when corner RPS reactor 240 is completely cleaned, when corner RPS reactor 250 is determined to be sufficiently cleaned, after a set period of time, at the request of an operator, or at any other time.

[0039] In one or more embodiments, operation 330b and operation 332b start at the same time. In one or more embodiments, operation 330b starts before operation 332b. In one or more embodiments, operation 332b starts before 330b. In one or more embodiments, operation 310b, operation 320b, and operation 330b are completed before starting operation 312b, operation 322b, and operation 332b. In one or more embodiments, operation 312b, operation 322b, and operation 332b are completed before starting operation 310b, operation 320b, and operation 330b.

[0040] Figure 4is a schematic graphical view of a chart showing the effect of clean gas flow rate on the clean rate of a chemical vapor deposition chamber. When the clean gas flow rate to the corner RPS reactor 240 is increased, the clean rate (in A / min) remains stable. However, when the clean gas flow rate to the center RPS reactor 250 is increased, there is an approximately logarithmic increase in the clean rate. Similarly, the overall clean rate increases with the increase of clean gas, but tends to level off.

[0041] Figure 5 is a schematic graphical representation of a chart showing the effect of the length of the first cleaning process on the cleaning rate of the chemical vapor deposition chamber. In one or more embodiments, the first cleaning process may be Figure 3B The second cleaning process is performed in operation 320b and operation 322b, and the second cleaning process is operation 322b after operation 330b.

[0042] like Figure 5 As shown, the cleaning rate of the center RPS reactor 250 increases significantly at the beginning, but tends to level off. Likewise, the total cleaning rate of the processing chamber 100 increases significantly at the beginning, but tends to level off. The time in the first cleaning process has little effect on the cleaning rate of the corner RPS reactor 240.

[0043] Table 1

[0044]

[0045] Table 1 details the Figure 3B Experimental results of dual process cleaning process shown. In process 1, 32 slm of NF3 flows to the center RPS reactor 250, and 12 slm of NF3 flows to the four corner RPS reactors 240, with a total flow rate of 80 slm. In process 2, 0 slm of NF3 flows to the center RPS reactor 250, and 20 slm of NF3 flows to the four corner RPS reactors 240, with a total flow rate of 80 slm.

[0046] In Tests 1-7, Process 1 was run for the time period listed in the second column. In Tests 1-7, Process 2 was run until the process chamber was cleaned. Test 8 was used as a reference, in which Process 1 was run until the process chamber was cleaned. In Test 8, Process 2 was not run. The total cleaning rate of Test 8 was used as a baseline to compare Tests 1-7. Tests 1 and 2 had lower cleaning ratios compared to Test 8, so Tests 1 and 2 have negative ratios. Tests 3-7 had higher cleaning ratios compared to Test 8, so Tests 3-7 have positive ratios.

[0047] Table 2

[0048]

[0049] Table 2 shows the difference in cleaning rate between the single process and dual process cleaning processes.

[0050] In Test A, 16 slm of NF3 flowed to each of the corner RPS reactors 240, and 16 slm of NF3 flowed to the center RPS reactor 250, for a total flow rate of 80 slm. In the first example, the cleaning rate was 16,748 A / min. Using Test A as the base cleaning rate, the first example had a normalized cleaning rate of 100%.

[0051] In Test B, 20 slm of NF3 flowed to each of the corner RPS reactors 240, and 20 slm of NF3 flowed to the center RPS reactor 250, for a total flow rate of 100 slm. In the second example, the cleaning rate was 18,124 A / min. Using Test A as the base cleaning rate, Test B had a normalized cleaning rate of 108%.

[0052] In Test C, a dual process cleaning process was utilized. In the first process, 12 slm of NF3 flowed to each of the corner RPS reactors 240, and 32 slm of NF3 flowed to the center RPS reactor 250, for a total flow rate of 80 slm. In the second process, 20 slm of NF3 flowed to each of the corner RPS reactors 240, and 0 slm of NF3 flowed to the center RPS reactor 250, for a total flow rate of 80 slm. In Test C, the cleaning rate was 18,227 A / min. Using Test A as the base cleaning rate, Test C had a normalized cleaning rate of 109%.

[0053] The benefits of the present disclosure include optimizing the amount of cleaning gas used to clean the processing chamber. By utilizing less cleaning gas, this reduces the cost of the cleaning gas and the amount of wasted gas generated during the cleaning operation. The present disclosure also has the benefit of reducing the time required to clean the processing chamber.

[0054] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the following claims.

Claims

1. A method for cleaning a chemical vapor deposition chamber, the method comprising: initiating flow of a cleaning gas to a central remote plasma source (RPS) reactor in a processing chamber; initiating flow of the cleaning gas to four corner RPS reactors in the process chamber; flowing a clean gas to the central RPS reactor and the four corner RPS reactors; stopping the flow of the clean gas to the central RPS reactor; and The flow of the clean gas to the four corner RPS reactors was stopped.

2. The method of claim 1 wherein said initiating said flow of said cleaning gas to said RPS reactor and said four corner RPS reactors occurs simultaneously.

3. The method of claim 2, wherein said stopping said flow of said cleaning gas to said center RPS reactor and said four corner RPS reactors occurs simultaneously.

4. The method of claim 1, wherein the flow of the clean gas to the center RPS reactor is stopped before stopping the flow of the clean gas to the four corner RPS reactors.

5. The method of claim 4, further comprising increasing a flow rate of the clean gas to the four corner RPS reactors after stopping the flow of the clean gas to the center RPS reactor.

6. The method of claim 1, wherein stopping the flow of the clean gas to the central RPS reactor occurs 10 seconds to 30 seconds after flowing the clean gas to the central RPS reactor.

7. The method of claim 1, wherein stopping the flow of the cleaning gas to the corner RPS reactor occurs after cleaning the chemical vapor deposition chamber.

8. The method of claim 1, wherein the cleaning gas comprises NF3, F2, or SF6.

9. The method of claim 1, wherein the cleaning gas comprises an inert gas.

10. A non-transitory storage medium having stored thereon instructions, which, when executed by a processor, cause the processor to perform operations for cleaning a chemical vapor deposition chamber, the instructions comprising: initiating flow of a cleaning gas to a central remote plasma source (RPS) reactor in a processing chamber; initiating flow of the cleaning gas to four corner RPS reactors in the process chamber; flowing a clean gas to the central RPS reactor and the four corner RPS reactors; stopping the flow of the clean gas to the central RPS reactor; and The flow of the clean gas to the four corner RPS reactors was stopped.

11. The non-transitory storage medium of claim 10, wherein instructing said initiating said flow of said cleaning gas to said RPS reactor and said four corner RPS reactors occurs simultaneously.

12. The non-transitory storage medium of claim 11, wherein instructing the stopping of the flow of the cleaning gas to the center RPS reactor and the four corner RPS reactors occurs simultaneously.

13. The non-transitory storage medium of claim 10, wherein the flow of the clean gas to the center RPS reactor is instructed to stop before stopping the flow of the clean gas to the four corner RPS reactors.

14. The non-transitory storage medium of claim 13, further comprising instructions for increasing a flow rate of the clean gas to the four corner RPS reactors after stopping the flow of the clean gas to the center RPS reactor.

15. The non-transitory storage medium of claim 10, wherein the instructions for flowing a clean gas to the central RPS reactor include a flow rate of a clean gas to the central RPS reactor of between 0 slm and 32 slm.

16. The non-transitory storage medium of claim 10, wherein the instructions for flowing a clean gas to the corner RPS reactor include a flow rate of a clean gas to the corner RPS reactor of between 12 slm and 20 slm.

17. A chemical vapor deposition chamber, comprising: a chamber body and a chamber cover; a central remote plasma source (RPS) reactor fluidly coupled to the center of the chamber lid; four corner RPS reactors, each corner RPS reactor fluidly coupled to a corresponding corner of the chamber lid; a common valve, fluidly connected to the four corner RPS reactors; a central valve fluidly connected to the central RPS reactor; as well as A clean gas supply is fluidly connected to the common valve.

18. The chemical vapor deposition chamber of claim 17, wherein the central valve is fluidly connected to the cleaning gas supply.

19. The chemical vapor deposition chamber of claim 17, wherein the cleaning gas supply is a first cleaning gas supply and the central valve is fluidly connected to a second cleaning gas supply.

20. The chemical vapor deposition chamber of claim 17, wherein the cleaning gas supplier is configured to supply a cleaning gas and an inert gas.

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