Atomic oxygen and ozone equipment for cleaning and surface treatment

Abstract

To provide oxygen cleaning chambers and a method of atomic-oxygen-cleaning a substrate.SOLUTION: The oxygen cleaning chambers and the method of atomic-oxygen-cleaning a substrate provide generation of atomic oxygen in situ to oxidize materials on surfaces of the substrate. The atomic oxygen cleaning chamber includes a chamber body, a chamber lid, a processing volume defined by the chamber body and the chamber lid, a UV radiation generator including one or more UV radiation sources, a pedestal disposed in the processing volume, and a gas distribution assembly. The pedestal has a processing position corresponding to a distance from the UV radiation generator to an upper surface of the pedestal. The gas distribution assembly is configured to be connected to an ozone generator so as to distribute ozone onto the upper surface of the pedestal.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure generally relate to apparatus and methods for cleaning equipment. More particularly, embodiments of the present disclosure relate to an oxygen cleaning chamber and a method for atomic oxygen cleaning of substrates. [Background technology]

[0002] In semiconductor device cleaning, it is often desirable to remove contaminants from the surface of the substrate, thereby leaving the surface clean. Contaminants may be present that would otherwise negatively impact semiconductor device performance. The cleanliness of semiconductor devices such as substrates, photomask photoresist strips, and chamber components impacts product yield, chamber uptime, and customer costs.

[0003] Most substrate cleaning techniques utilize oxygen-containing cleaning agents exposed to ultraviolet (UV) radiation to oxidize the surface of the substrate. Compared to other oxygen-containing cleaning agents, atomic oxygen has the highest reaction rate and oxidizing power, allowing the surface of the substrate to be cleaned at a higher rate for greater throughput. However, atomic oxygen has a short lifetime, and once formed, atomic oxygen combines with O2 and other molecules in the oxygen-containing cleaning agent.

[0004] Therefore, there is a need in the art for an improved oxygen cleaning chamber and method for atomic oxygen cleaning of substrates. Summary of the Invention

[0005] In one embodiment, an atomic oxygen cleaning chamber is provided. The atomic oxygen cleaning chamber includes a chamber body, a chamber lid, a process volume defined by the chamber body and the chamber lid, an ultraviolet (UV) radiation generator including one or more UV radiation sources, a pedestal disposed within the process volume, and a gas supply assembly. The pedestal has a process position corresponding to a distance from the UV radiation generator to a top surface of the pedestal. The gas supply assembly is operable to supply ozone above the top surface of the pedestal.

[0006] In another embodiment, a system is provided. The system includes one or more service chambers and one or more atomic oxygen cleaning chambers coupled to a transfer chamber. The transfer chamber houses a robot, which is used to transfer substrates between the one or more service chambers and the one or more atomic oxygen cleaning chambers. Each of the one or more atomic oxygen cleaning chambers includes a chamber body, a chamber lid, a processing volume defined by the chamber body and the chamber lid, a UV radiation generator including one or more ultraviolet (UV) radiation sources, a pedestal disposed within the processing volume, and a gas supply assembly. The pedestal has a processing position corresponding to a distance from the UV radiation generator to a top surface of the pedestal. The gas supply assembly is operable to supply ozone above the top surface of the pedestal.

[0007] In yet another embodiment, a method for atomic oxygen cleaning of a substrate is provided. The method includes placing a substrate having one or more surfaces on an upper surface of a pedestal disposed within a processing volume of an atomic oxygen cleaning chamber. The upper surface of the pedestal is remote from an ultraviolet (UV) radiation generator of the atomic oxygen cleaning chamber. A first surface of the one or more surfaces is directed toward the UV radiation generator. Ozone is flowed into the processing volume such that the ozone is distributed across the first surface of the substrate. Radiation having a wavelength between about 240 nanometers (nm) and about 310 nm is emitted from the UV generator toward the ozone.

[0008] So that the above-listed features of the present disclosure can be understood in detail, the present disclosure briefly summarized above may be more particularly described by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings depict only exemplary embodiments and, therefore, should not be considered as limiting in scope, since the present disclosure is susceptible to other equally effective embodiments. [Brief explanation of the drawings]

[0009] [Figure 1A] 1 is a schematic cross-sectional view of an atomic oxygen cleaning chamber according to one embodiment described herein. [Figure 1B] 1 is a simplified cross-sectional view of a chamber body of an atomic oxygen cleaning chamber according to one embodiment described herein. [Figure 2] 1 is a schematic cross-sectional view of an atomic oxygen cleaning chamber according to one embodiment described herein. [Figure 3] 1 is a schematic diagram of a system according to one embodiment described herein. [Figure 4] 1 is a flow diagram of a method for atomic oxygen cleaning a substrate according to one embodiment described herein. DETAILED DESCRIPTION OF THE INVENTION

[0010] For ease of understanding, where possible, identical reference numerals have been used to designate identical elements common to the figures. Unless otherwise noted, it is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments.

[0011] Embodiments described herein relate to an oxygen cleaning chamber and a method for atomic oxygen cleaning of a substrate, which provides for the in-situ generation of atomic oxygen to oxidize material on the surface of a substrate.

[0012] 1A is a schematic cross-sectional view of an atomic oxygen cleaning chamber 100. In one embodiment, the atomic oxygen cleaning chamber 100 is utilized for a method 400 of atomic oxygen cleaning a substrate. The atomic oxygen cleaning chamber 100 has a chamber body 102 and a chamber lid 104. The atomic oxygen cleaning chamber 100 includes a processing volume 106. The processing volume 106 is a space defined by the chamber body 102 and the chamber lid 104. The processing volume 106 has a pedestal 110 for supporting a substrate 101 within the atomic oxygen cleaning chamber 100. The pedestal 110 is supported by a stem 112. The pedestal 110 is movably disposed within the processing volume 106 by a stem 112 that extends through the chamber body 102 and is connected to a lift system (not shown) that moves the pedestal 110 between a processing position (as shown) and a transfer position that facilitates substrate transfer to and from the processing volume 106 through a slit valve 114 formed in the chamber body 102. The processing position corresponds to a distance 116 from an ultraviolet (UV) radiation generator 156 to an upper surface 120 of the pedestal 110.

[0013] As shown in FIG. 1A, the atomic oxygen cleaning chamber 100 includes a gas supply assembly 122. The gas supply assembly 122 includes a gas inlet 124, an oxygen-containing gas source 126, an ozone (O) generator 128, and a flow controller 130. The ozone generator 128 is fluidly connected to the oxygen-containing gas source 126 via a first conduit 132. The ozone generator 128 is capable of generating ozone from the oxygen-containing gas and maintaining the ozone at a constant pressure and concentration. A flow controller 130, such as a mass flow controller (MFC), fluidly connected to the ozone generator via a second conduit 134 controls the flow rate of ozone from the ozone generator 128. The atomic oxygen cleaning chamber 100 includes a controller 118. The controller 118 includes a central processing unit (CPU), memory, and support circuits for the CPU. The controller 118 enables control of the operating parameters and operations of the atomic oxygen cleaning chamber 100 , such as the method 400 for atomic oxygen cleaning of the substrate 101 .

[0014] FIG. 1B is a schematic cross-sectional view of the chamber body 102 having a gas inlet 124 and a gas outlet 140. The gas inlet 124 includes a manifold 142 and a flow guide 144. The manifold 142 is connected to the ozone generator 128 via a third conduit 136. An ozone flow is distributed throughout the manifold 142, flows through multiple channels 146 in the flow guide 144, and is distributed onto the upper surface 120 of the pedestal 110. The gas outlet 140 is disposed in the chamber body 102. Referring to FIG. 1A, the UV radiation generator 156 includes one or more UV radiation sources 158 coupled to the chamber lid 104. In one embodiment, which can be combined with other embodiments described herein, at least one of the one or more UV radiation sources 158 is a low-pressure mercury lamp. A pump 138 is coupled to the gas outlet 140 for controlling the pressure within the processing volume 106 and for evacuating by-products from the processing volume 106 through the gas outlet 140 via a fourth conduit 141 .

[0015] FIG. 2 is a schematic cross-sectional view of an atomic oxygen cleaning chamber 200 according to one embodiment. The atomic oxygen cleaning chamber 200 includes a gas supply assembly 202. The gas supply assembly 202 includes an oxygen-containing gas source 126, an ozone (O) generator 128, and a flow controller 130. As further shown in FIG. 2 , the gas supply assembly 202 includes a plenum 204 formed in the chamber lid 104 and a showerhead 206 coupled to the plenum 204. The showerhead 206 has a plurality of channels 208. An ozone flow is distributed throughout the plenum 204, flows through the plurality of channels 208 in the showerhead 206, and is distributed onto the upper surface 120 of the pedestal 110. A UV radiation generating device 156 including one or more UV radiation sources 158 is coupled to the showerhead 206. In one embodiment, which can be combined with other embodiments described herein, at least one of the one or more UV radiation sources 158 is a low-pressure mercury lamp. A pump 138 is coupled to the outlet 154 of the chamber body 102 to control the pressure within the process volume 106 and to evacuate by-products from the process volume 106 via a fourth conduit 141. The controller 118 enables control of the operating parameters and operations of the atomic oxygen cleaning chamber 200, such as the method 400 for atomic oxygen cleaning of the substrate 101.

[0016] 1A and 2, the UV radiation generator 156 includes one or more UV radiation sources 158 that generate UV radiation. The UV radiation sources 158 can be lamps, LED emitters, or other UV emitters configured to emit radiation with wavelengths between about 240 nm and about 310 nm. Ozone provided on the surface of the substrate 101 is exposed to this radiation and converted to oxygen gas (O) and atomic oxygen (O). The oxygen gas and atomic oxygen oxidize inorganic materials, such as hydrocarbons, on the surface of the substrate 101, producing carbon dioxide (CO) and water (HO) as by-products. The pump 138 evacuates the by-products from the process volume 106.

[0017] Compared to other oxygen-containing cleaning agents, atomic oxygen has the highest reaction rate and oxidizing power, allowing the surface of the substrate 101 to be cleaned at a faster rate for greater throughput. For example, atomic oxygen can instantly oxidize SO2 on the surface of the substrate 101 to SO3, which can then be easily removed by a subsequent water rinsing step. Removing SO2 by atomic oxygen cleaning of the substrate 101 slows the accumulation of haze defects. However, atomic oxygen has a short lifetime, and once formed, it combines with O2 and other molecules. The ozone generator 128 can continuously supply ozone to the process volume 106 such that radiation generated by the UV radiation generator 156 converts the ozone to atomic oxygen in situ. In situ atomic oxygen generation within the process volume provides a high concentration of atomic oxygen to the surface of the substrate 101. The distance 116 from the UV radiation generator 156 to the upper surface 120 of the pedestal 110 controls the concentration of atomic oxygen provided to the surface of the substrate 101 .

[0018] 3 is a schematic diagram of a system 300 utilized for a method 400 of atomic oxygen cleaning a substrate. It is understood that the system described below is an exemplary system, and that other systems, including systems from other manufacturers, can be used with and modified to achieve aspects of the present disclosure. The system 300 includes one or more service chambers 304 coupled to a transfer chamber 306 and one or more of the atomic oxygen cleaning chambers 301. In another embodiment, the system 300 includes one or more processing chambers 302 coupled to the transfer chamber 306. The one or more service chambers 304 are adapted for at least one of degassing, alignment, cool-down, pre-treatment / pre-cleaning, post-annealing, etc. The one or more processing chambers 302 are adapted for at least one of rapid thermal processing (RTP), epitaxial (EPI) deposition, chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), etc. The transfer chamber 306 houses a robot 308 that is used to transfer substrates between the service chamber 304 , the processing chamber 302 and the atomic oxygen cleaning chamber 301 .

[0019] Figure 4 is a flow diagram of a method 400 for atomic oxygen cleaning a substrate. For ease of explanation, Figure 4 will be described with reference to Figures 1A, 1B, and 2. However, it should be noted that atomic oxygen cleaning chambers other than atomic oxygen cleaning chamber 100 and atomic oxygen cleaning chamber 200 can be utilized with method 400, and that systems other than system 300 can be utilized with method 400.

[0020] In optional operation 401, the substrate 101 is transferred to the atomic oxygen cleaning chamber 301. In one embodiment that may be combined with other embodiments described herein, the atomic oxygen cleaning chamber 301 is the atomic oxygen cleaning chamber 100. In another embodiment that may be combined with other embodiments described herein, the atomic oxygen cleaning chamber 301 is the atomic oxygen cleaning chamber 200. In one embodiment that may be combined with other embodiments described herein, the robot 308 of the system 300 transfers the substrate 101 from the processing chamber 302 or the service chamber 304 to the atomic oxygen cleaning chamber 301. In operation 402, which may be combined with other embodiments described herein, the substrate 101 is placed on the pedestal 110. A first surface of the substrate 101, having one or more surfaces, is directed toward the UV radiation generating device 156. In one embodiment, which can be combined with other embodiments described herein, the distance 116 from the ultraviolet (UV) radiation generator 156 to the upper surface 120 of the pedestal 110 is between about 7 millimeters (mm) and about 30 mm. In operation 403, an ozone flow is provided to the processing volume 106. In one embodiment, ozone gas is flowed into the processing volume 106 at a flow rate between about 50 sccm and about 20,000 sccm. In another embodiment, which can be combined with other embodiments described herein, the pressure in the atomic oxygen cleaning chamber 301 is between about 0 psi and about 15 psi. The ozone flow is provided over the first surface of the substrate 101 in the processing volume 106. In operation 404, the UV radiation generator 156 emits radiation. The ozone flow provided over the first surface of the substrate 101 in the processing volume 106 is exposed to the radiation and converted into oxygen gas (O) and atomic oxygen (O). The oxygen gas and atomic oxygen oxidize organic materials, such as hydrocarbons, on the first surface of the substrate 101, producing carbon dioxide (CO) and water (HO) as by-products. In operation 405, the by-products are removed from the processing volume 106. In optional operation 406, operations 403 and 404 are repeated for a subsequent surface of the substrate 101. At the end of method 400, the robot 308 of the system 300 can transfer the substrate 101 from the atomic oxygen cleaning chamber 301 to a processing chamber 302 or a service chamber 304.

[0021] In summary, described herein are atomic oxygen cleaning chambers and methods for atomic oxygen cleaning of substrates. Compared to other oxygen-containing cleaning agents, atomic oxygen has the highest reaction rate and oxidizing power, resulting in faster cleaning of substrate surfaces for greater throughput. Each atomic oxygen cleaning chamber includes an ozone generator that continuously provides ozone to a processing volume such that radiation generated by a UV radiation generator converts the ozone to atomic oxygen in situ. The in situ atomic oxygen generation within the processing volume provides a high concentration of atomic oxygen to the surface of the substrate.

[0022] While the foregoing is directed to examples of the disclosure, other and further examples of the disclosure may be devised without departing from the basic scope thereof, the scope of which is determined by the claims that follow.

Claims

1. a chamber body; Chamber lid and a processing volume defined by the chamber body and the chamber lid; an ultraviolet (UV) radiation generating device including one or more UV radiation sources; a pedestal disposed within the processing volume, the pedestal having a processing position corresponding to a distance from the UV radiation generating device to a top surface of the pedestal; a gas supply assembly operable to supply ozone through a gas inlet of the chamber body above the upper surface of the pedestal and to supply by-products to a gas outlet of the chamber body; Equipped with An atomic oxygen cleaning chamber, wherein the one or more ultraviolet (UV) radiation sources are coupled to the chamber lid, positioned within the processing volume, and located between the gas inlet and an underside of the chamber lid within the processing volume.

2. the gas supply assembly a plenum formed in the chamber lid, the plenum configured to be connected to an ozone generator; a showerhead coupled to the plenum, the showerhead having a plurality of channels for supplying ozone onto the top surface of the pedestal; The atomic oxygen cleaning chamber of claim 1 , comprising:

3. the gas supply assembly a gas inlet formed in the chamber body, the gas inlet a manifold configured to be connected to an ozone generator; a flow guide having a plurality of channels for supplying ozone onto the top surface of the pedestal; 10. The atomic oxygen cleaning chamber of claim 1, comprising:

4. The atomic oxygen cleaning chamber of claim 1 , wherein the one or more UV radiation sources are configured to emit radiation at wavelengths between 240 nanometers (nm) and 310 nm.

5. 10. The atomic oxygen cleaning chamber of claim 1, wherein the pedestal is connected to a stem operable to move the pedestal between the processing position and a transfer position.

6. one or more service chambers and one or more atomic oxygen cleaning chambers coupled to the transfer chamber; a robot housed in the transfer chamber that is used to transfer substrates between the one or more service chambers and the one or more atomic oxygen cleaning chambers; each of the one or more atomic oxygen cleaning chambers comprising: a chamber body; Chamber lid and a processing volume defined by the chamber body and the chamber lid; an ultraviolet (UV) radiation generating device including one or more UV radiation sources; a pedestal disposed within the processing volume, the pedestal having a processing position corresponding to a distance from the UV radiation generating device to a top surface of the pedestal; a gas supply assembly operable to supply ozone from a plenum formed in the chamber lid onto the top surface of the pedestal through a showerhead connected to the plenum having a plurality of channels; Equipped with The one or more ultraviolet (UV) radiation sources are disposed within the processing volume and coupled to an underside of the showerhead within the processing volume.

7. The system of claim 6 , wherein the plenum is configured to be connected to an ozone generator.

8. the gas supply assembly a gas inlet formed in the chamber body, the gas inlet a manifold configured to be connected to an ozone generator; a flow guide having a plurality of channels for supplying ozone onto the top surface of the pedestal; The system of claim 6 , comprising:

9. The system of claim 6 , wherein the one or more UV radiation sources are configured to emit radiation at wavelengths between 240 nanometers (nm) and 310 nm.

10. 7. The system of claim 6, wherein the pedestal is connected to a stem operable to move the pedestal between the processing position and a transfer position.

11. The system of claim 6 , wherein the one or more service chambers are adapted for at least one of degassing, orientation, cool down, pre-cleaning, and post-annealing processes.

12. 1. A method for atomic oxygen cleaning of a substrate, comprising: placing a substrate having one or more surfaces on an upper surface of a pedestal disposed within a processing volume of an atomic oxygen cleaning chamber, the upper surface of the pedestal being spaced apart from an ultraviolet (UV) radiation generating device of the atomic oxygen cleaning chamber, the UV radiation generating device being coupled to a chamber lid and disposed within the processing volume, and a first surface of the one or more surfaces facing toward the UV radiation generating device; flowing ozone into the process volume through a gas inlet of a chamber body such that the ozone is delivered onto the first surface of the substrate and by-products flow toward a gas outlet of the chamber body; emitting radiation from the UV radiation generating device toward the ozone at a wavelength between 240 nanometers (nm) and 310 nm; A method comprising:

13. 13. The method of claim 12, wherein a flow of ozone is supplied throughout a gas inlet manifold disposed in a chamber body of the atomic oxygen cleaning chamber, flows through a plurality of channels in a gas inlet flow guide, and is supplied onto the first surface of the substrate in the processing volume.

14. 13. The method of claim 12, further comprising positioning a second surface of the substrate and repeating the flow of ozone into the process volume, the supply of ozone, and the emission of radiation.

15. 13. The method of claim 12, wherein the distance from the UV radiation generating device to the top surface of the pedestal is between 7 millimeters (mm) and 30 mm.

16. 13. The method of claim 12, wherein the ozone is flowed into the processing volume of the atomic oxygen cleaning chamber at a flow rate between 50 sccm and 20,000 sccm.

17. The method of claim 12, wherein the pressure in the processing volume is between 0 psi and 15 psi.

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