UV and ozone cleaning system

Abstract

A cleaning apparatus for cleaning a substrate includes a lamp for emitting ultraviolet light in an irradiation area, a housing for accommodating the lamp, a water deflector spaced apart below the housing, the water deflector having a water inlet for receiving a supply of ozone water and a water outlet for discharging the ozone water irradiated by the lamp into a substrate processing area below the water deflector, the water deflector defining a water flow path between the water inlet and the water outlet, the water flow path extending into the irradiation area, an upper reflector extending along and above the lamp, and a lower reflector extending along and below the water deflector, the upper reflector and the lower reflector at least partially defining the irradiation area and reflecting ultraviolet light toward the water flow path, and the lower reflector shielding the substrate from the ultraviolet light emitted by the lamp.

Description

[Technical field]

[0001] TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate generally to cleaning systems, and more specifically to ultraviolet and ozone cleaning systems. [Background technology]

[0002]

[0002] Substrates used in the semiconductor manufacturing industry are often cleaned to remove unwanted material, such as contaminants or other unwanted particles generated thereon during processing. Substrates can include semiconductor wafers, chamber components, photomasks, etc.

[0003]

[0003] Contaminants can be removed by cleaning the substrate with UV-irradiated ozone water. The water can be irradiated by an UV source that emits UV light. However, the inventors have observed that some UV-ozone water cleaning apparatus and methods expose the substrate to the irradiated UV light, which in itself can be an undesirable factor in removing or altering additional material other than the contaminants to be cleaned. The removal or alteration of additional material can cause defects in the substrate.

[0004] Accordingly, the present inventors have provided an improved cleaning apparatus and method for cleaning a substrate. Summary of the Invention

[0005]

[0005] Embodiments of an apparatus and method for cleaning a substrate are provided herein. In some embodiments, the apparatus for cleaning a substrate includes a lamp configured to emit ultraviolet light in an irradiation area, a housing for receiving the lamp, the housing defining a cooling chamber surrounding the lamp, a water deflector spaced below the housing, the water deflector having a water inlet for receiving a supply of ozone water and a water outlet for discharging the ozone water irradiated by the lamp into a substrate processing area below the water deflector, defining a water flow path between the water inlet and the water outlet, the water flow path extending into the irradiation area, an upper reflector extending above the lamp along the lamp in the cooling chamber of the housing, and a lower reflector extending below the water deflector along the water deflector, the upper reflector and the lower reflector at least partially defining the irradiation area, the lower reflector configured to reflect ultraviolet light emitted by the lamp toward the water flow path, and the lower reflector configured to shield the substrate from the ultraviolet light emitted by the lamp.

[0006]

[0006] In some embodiments, an apparatus for cleaning a substrate includes a lamp configured to emit ultraviolet light in an irradiation area, a housing for receiving the lamp, the housing defining a cooling chamber surrounding the lamp, a water deflector spaced below the housing, the water deflector having a water inlet for receiving a supply of ozone water and a water outlet for discharging the ozone water irradiated by the lamp into a substrate processing area below the water deflector, defining a water flow path between the water inlet and the water outlet, the water flow path extending into the irradiation area, and an upper water deflector extending above the lamp along the lamp within the cooling chamber of the housing. The cleaning apparatus includes a reflector and a lower reflector extending below the water deflector along the water deflector, where the upper and lower reflectors at least partially define an irradiation area and are configured to reflect ultraviolet light emitted by the lamps toward the water flow path, and the lower reflector is configured to shield the substrate from the ultraviolet light emitted by the lamps, and a substrate support that supports the substrate below the lower reflector in the substrate processing area, the substrate support being configured to rotate the substrate, and the cleaning apparatus is configured to translate horizontally while flowing the irradiated ozone water within the substrate processing area.

[0007] In some embodiments, a method for cleaning a substrate includes flowing ultraviolet irradiated ozone water over the substrate while shielding the substrate from the ultraviolet light.

[0008]

[0008] Other further embodiments of the present disclosure are described below.

[0009]

[0009] The embodiments of the present disclosure summarized above and described in more detail below can be understood by reference to the exemplary embodiments of the present disclosure illustrated in the accompanying drawings. However, the accompanying drawings merely illustrate typical embodiments of the present disclosure and therefore should not be considered as limiting the scope, the present disclosure being open to other equally effective embodiments. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram illustrating a multi-chamber processing tool having a cleaning chamber in accordance with at least some embodiments of the present disclosure. [Diagram 2] 2 is a schematic diagram illustrating a cleaning apparatus for a cleaning chamber of the multi-chamber processing tool shown in FIG. 1. [Diagram 3] FIG. 3 illustrates a cleaning workflow employing the cleaning apparatus shown in FIG. 2, in accordance with at least some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011]

[0013] To facilitate understanding, the same reference numbers have been used, whenever possible, to designate identical elements common to the drawings. The drawings are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be beneficially incorporated in other embodiments without further detail.

[0012]

[0014] An embodiment of a cleaning chamber for cleaning a substrate is provided herein. The cleaning chamber is configured to clean the substrate to remove unwanted particles or residues after the substrate has undergone a wet cleaning or dry cleaning process. The substrate may be, for example, a semiconductor wafer, a photomask, etc. In the example of a photomask, photoresist may remain on the substrate. UV-irradiated ozone water is flowed onto the photoresist, causing the photoresist to dissociate from the photomask. The dissociated residues and water are then removed from the interior region of the cleaning chamber.

[0013]

[0015] FIG. 1 is a schematic diagram illustrating a multi-chamber processing tool (tool) 100 having one or more wet clean chambers 130 (three are shown in FIG. 1 ) according to at least some embodiments of the present disclosure. The tool 100 described below is shown in an exemplary configuration, and other configurations may be used. The tool 100 generally includes a factory interface 102, a transfer chamber 106 coupled to the factory interface 102, and multiple process chambers 105 including wet clean chambers 130 coupled to the transfer chamber 106. The factory interface 102 includes multiple load ports 104 for receiving one or more substrates 112. The one or more substrates 112 may be semiconductor wafers, carrier substrates, photomasks, etc. In some embodiments, the multiple load ports 104 are disposed along a common side of the factory interface 102. A factory interface robot 110 is disposed in an interior region 108 of the factory interface 102 and can shuttle or transport the one or more substrates 112 from the multiple load ports 104 to the transfer chamber 106. The factory interface robot 110 may be configured for rotational movement within the interior region 108, lateral movement within the interior region 108, or both.

[0014]

[0016] The transfer chamber 106 is coupled to the factory interface 102 and, in some embodiments, is located on an opposite side of the factory interface 102 from the plurality of load ports 104. The transfer chamber 106 includes a transfer robot 116 disposed therein for moving one or more substrates 112 received from the factory interface robot 110 to and from one or more process chambers 105 coupled to the transfer chamber. The transfer robot 116 may be configured for rotational movement, lateral movement, or both. For example, lateral movement may be accomplished via rails on the floor of the transfer chamber 106 or via tracks below the transfer robot 116. An arm 122 of the transfer robot 116 is extendable to move one or more substrates 112 in and out of each of the plurality of process chambers 105.

[0015]

[0017] In some embodiments, the transfer robot 116 is configured to receive the one or more substrates 112 directly from the factory interface robot 110. In some embodiments, the transfer robot 116 is configured to receive the one or more substrates 112 indirectly from the factory interface robot 110. For example, in some embodiments, one of the factory interface 102 or the transfer chamber 106 includes a buffer 120 configured to hold one or more of the one or more substrates 112. The transfer robot 116 may be configured to transfer the one or more substrates 112 to the buffer 120, and the transfer robot 116 may be configured to transfer the one or more substrates 112 from the buffer 120 to the multiple process chambers 105 and back from the multiple process chambers 105 to the buffer 120.

[0016]

[0018] The transfer chamber 106 may have one or more environmental controls. For example, the airflow openings of the transfer chamber 106 may include filters to filter the airflow entering the transfer chamber 106. Other environmental controls may include one or more of humidity control, static control, temperature control, or pressure control.

[0017]

[0019] The one or more process chambers 105 may be orthogonally coupled to the transfer chamber 106 or may be coupled at an angle to the transfer chamber 106. The multiple process chambers 105 may be in sealing engagement with the transfer chamber 106. The transfer chamber 106 typically operates at atmospheric pressure, but may also be configured to operate at vacuum pressure. The multiple process chambers 105 are configured to perform one or more processing steps on one or more substrates 112 being processed in the tool 100. For example, the multiple process chambers 105 may include one or more wet cleaning chambers 130 (three shown in FIG. 1 ) configured to clean the one or more substrates 112 with a liquid, e.g., water. The multiple process chambers 105 may include one or more dry cleaning chambers 140 (two shown in FIG. 1 ) configured to perform a dry cleaning process on the one or more substrates 112, e.g., via a plasma etching or plasma ashing procedure. The one or more process chambers 105 include at least one bake chamber, such as bake chamber 150 configured to heat one or more substrates to remove residue or haze remaining after a wet cleaning or dry cleaning process. In some embodiments, the one or more wet cleaning chambers 130 are located on a different side of the transfer chamber 106 than the one or more dry cleaning chambers 140.

[0018]

[0020] Figure 2 is a schematic diagram of a cleaning apparatus 200 housed in a wet clean chamber 130 of the multi-chamber processing tool 100 of Figure 1. In some embodiments, the wet clean chamber 130 may form a portion of the cleaning apparatus 200. Figure 2 shows the cleaning apparatus 200 being used to clean a substrate 112. Although described with reference to a particular wet clean chamber 130 of the multi-chamber processing tool 100 above, the cleaning apparatus 200 may be housed in wet clean chambers having other configurations than those that may be in processing tools having other configurations, including being used as a stand-alone tool without being coupled to a multi-chamber processing tool.

[0019]

[0021] The cleaning apparatus 200 includes a lamp 202 configured to emit ultraviolet light at illumination areas 204 above and below the lamp 202. The lamp 202 may be a low pressure mercury ultraviolet lamp. The lamp 202 may operate at approximately 30 to 150 watts and emit ultraviolet light having a spectrum defined by peak amplitudes at wavelengths from 240 nanometers to 310 nanometers. In some embodiments, the lamp emits ultraviolet light having a primary ultraviolet emission at approximately 254 nanometers.

[0020]

[0022] The cleaning apparatus 200 also includes a housing 206 that houses the lamp 202. The housing 206 defines a cooling chamber 208 that surrounds the lamp 202. In the embodiment shown in FIG. 2, the housing 206 may include a top cover 206a and a bottom cover 206b that are sealingly engaged with one another, such as with an O-ring 206c. The top cover 206a may be formed from polytetrafluoroethylene (PTFE) and the bottom cover 206b may be formed from quartz that allows transmission of ultraviolet light emitted by the lamp 202. The housing 206 may have an inlet 206d and an outlet 206e. The inlet 206d and the outlet 206e may be formed in the top cover 206a as shown in the embodiment of FIG. 2. The inlet 206d may be fluidly coupled to a source of cooling fluid, such as cooled dry air. The outlet 206e may be fluidly coupled to an exhaust system for the cooling fluid. The inlet 206d and the outlet 206e are in fluid communication with a cooling chamber 208 that is configured to flow a cooling fluid between the inlet 206d and the outlet 206e and over the lamp 202. The flow of the cooling fluid over the lamp 202 cools the lamp 202 and controls the temperature of the lamp 202.

[0021]

[0023] The temperature of the lamp 202 may affect the peak amplitude of the emission spectrum emitted by the lamp 202. For example, a lower temperature may reduce the peak amplitude. In an embodiment, the cleaning apparatus 200 may include an ultraviolet monitor 203 for monitoring the peak amplitude of the emission spectrum of the lamp 202, which may be used as feedback to adjust the temperature of the lamp 202, i.e., by adjusting parameters of the cooling fluid passing through the cooling chamber 208, such as the flow rate of the cooling fluid and the inlet temperature of the cooling fluid. The ultraviolet monitor 203 may be connected to the housing 206 as shown in FIG. 2.

[0022]

[0024] The cleaning apparatus 200 also includes a water deflector 210 spaced below the housing 206. The water deflector 210 has a water inlet 212 for receiving a supply of ozone water 214 and a water outlet 216 for discharging the ozone water irradiated by the lamps 202 into a substrate processing region 218 below the water deflector 210. The water deflector 210 defines a water flow path 220 between the water inlet 212 and the water outlet 216. The water flow path 220 extends into the irradiation region 204 so that the ozone water can be irradiated by ultraviolet light emitted by the lamps 202 as it passes through the irradiation region 204 toward the water outlet 216. The water deflector 210 may be formed of quartz and may allow transmission of ultraviolet light emitted by the lamps 202.

[0023]

[0025] The cleaning apparatus 200 also includes an upper reflector 222 that may be disposed within the cooling chamber 208 of the housing 206, as shown in FIG. 2. The upper reflector 222 extends above and along the lamps 202. The cleaning apparatus 200 also includes a lower reflector 224 that extends below the lamps 202 along and below the water deflector 210. The upper reflector 222 and the lower reflector 224 at least partially define the illumination area 204 and are configured to reflect the ultraviolet light emitted by the lamps 202 toward the water flow path 220. The lower reflector 224 is configured to shield the substrate processing area 218 (and the substrate 112 in the substrate processing area 218) from the ultraviolet light emitted by the lamps 202. The upper reflector 222 and the lower reflector 224 may be formed of aluminum or an aluminum alloy, or any other suitable material capable of reflecting ultraviolet light and providing shielding to the substrate processing area 218.

[0024]

[0026] The cleaning apparatus 200 may also include a substrate support 228 located in the substrate processing region 218. The substrate support 228 has a plate 228a and a shaft 228b extending from the plate 228a to the wet cleaning chamber 130. The substrate support 228 is rotatably connected to the wet cleaning chamber 130. The substrate support 228 is configured to rotate about a central axis 226 extending vertically through the shaft 228b. As shown in FIG. 2, the plate 228a is configured to support the substrate 112 in the substrate processing region 218 while the ultraviolet irradiated ozone water flows over the substrate 112.

[0025]

[0027] The water deflector 210 may extend horizontally from the housing 206 to laterally space the water outlet 216 from the housing 206. The water deflector 210 may extend horizontally from the housing 206 a distance of 0.5 inches to 4 inches. Additionally, the water outlet 216 may be vertically spaced approximately 2.5 inches from the top surface of the substrate 112.

[0026]

[0028] The cleaning apparatus 200 may include a reflector protector 230 that may support at least one of the water deflector 210 and the bottom reflector 224. The reflector protector 230 may have a first end 230a and a second end 230b coupled to the water deflector 210. The reflector protector 230 may be connected to the wet cleaning chamber 130 via an actuator 232 (e.g., a linear actuator) configured to translate the water deflector 210 and the water outlet 216 within the wet cleaning chamber 130 relative to the substrate support 228. In an embodiment, the water deflector 210 may be configured to translate while the substrate support 228 rotates about the central axis 226. By translating the water deflector 210 relative to the substrate support 228, a horizontal position of the water outlet 216 of the water deflector 210 above the substrate processing region 218 may be translated. Thus, when the substrate 112 is supported by the substrate support 228 in the substrate processing region 218, the UV-irradiated ozone water can be advantageously directed to different locations on the substrate 112 to be cleaned, resulting in more controlled (e.g., more uniform) cleaning process results.

[0027]

[0029] The wet clean chamber 130 may have a slit valve door 131 operable to open and close to allow the substrate 112 to be introduced or removed from the interior of the wet clean chamber 130, such as by a transfer robot 116 (FIG. 1).

[0028]

[0030] 3 illustrates a cleaning workflow 300 according to at least some embodiments of the present disclosure. At 302, the substrate 112 is placed on the plate 228a of the substrate support 228. The substrate 112 is positioned in the substrate processing region 218 and vertically below the water outlet 216. At 304, ozone water from the source of ozone water 214 flows through the irradiation region 204 along the water flow path 220. At 306, the UV-irradiated ozone water is discharged from the water outlet 216 and falls by gravity onto the substrate 112. During the cleaning workflow 300, the shaft 228b of the substrate support 228 can rotate about the central axis 226 to rotate the substrate 112 relative to the water deflector 210. Also, the water deflector 210 can be translated horizontally during the cleaning workflow 300. The rotation of shaft 228b may be coordinated with the translation of water deflector 210 or may be independent of the translation of water deflector 210. The UV irradiated ozone water may be dispensed onto the surface of substrate 112 for a predetermined time, or the process may be monitored to determine the end of the cleaning process, at which point UV lamps 202 may be turned off and the flow of ozone water may be stopped. The cleaned substrate 112 may then be removed from chamber 130, and if desired, a new substrate 112 may be introduced and the cleaning process may be performed again.

[0029]

[0031] While the forgoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof.

Claims

Claim 1 A cleaning device for cleaning a substrate, comprising: a lamp configured to emit ultraviolet rays in an irradiation region; a water deflector disposed at a distance below the lamp, having a water inlet for receiving supply of ozone water and a water outlet for discharging the ozone water irradiated by the lamp into a substrate processing region below the water deflector, defining a water flow path between the water inlet and the water outlet, the water flow path extending into the irradiation region, the water deflector; A cleaning device comprising the above. Claim 2. The cleaning device according to claim 1, further comprising an upper reflector extending upward along the lamp above the lamp, the upper reflector at least partially defining the irradiation region and configured to reflect ultraviolet rays emitted by the lamp toward the water flow path. Claim 3 The cleaning device according to claim 2, wherein the length of the upper reflector is equal to or greater than the length of the lamp. Claim 4. The cleaning device according to claim 1, further comprising a lower reflector extending along and below the water deflector, the lower reflector at least partially defining the irradiation region and configured to reflect ultraviolet rays emitted by the lamp toward the water flow path, the lower reflector being configured to shield the substrate from ultraviolet rays emitted by the lamp. Claim 5. The cleaning device according to claim 4, wherein the length of the lower reflector is equal to or greater than the length of the lamp. Claim 6 The cleaning device according to claim 4, further comprising a substrate support for supporting the substrate below the water outlet in the substrate processing region, the lower reflector being disposed between the water outlet and the substrate support. Claim 7. The cleaning device according to claim 1, wherein the lamp operates at 80 to 90 watts. Claim 8. The cleaning device according to claim 1, further comprising a substrate support for supporting the substrate below the water outlet in the substrate processing region, the substrate support being configured to rotate the substrate. **Claim 9**: The cleaning device according to claim 1, further comprising a housing for accommodating the lamp, wherein the housing defines a cooling chamber surrounding the lamp, the housing has an inlet and an outlet in fluid connection with the cooling chamber, and the cooling chamber is configured to direct a cooling fluid between the inlet and the outlet and over the lamp. **Claim 10** The cleaning device according to claim 9, wherein the cooling fluid includes cooled dry air. **Claim 11** The cleaning device according to claim 9, wherein the housing includes an upper cover and a lower cover sealed to the upper cover, and the inlet and the outlet are formed in the upper cover. **Claim 12** The cleaning device according to claim 11, wherein the upper cover is formed of PTFE and the lower cover is formed of quartz. **Claim 13** The cleaning device according to claim 9, wherein a horizontal distance between the water outlet and the housing is from 0.5 inch to 4 inches. **Claim 14** The cleaning device according to claim 13, wherein the horizontal distance is from 1 inch to 2 inches. **Claim 15** The cleaning device according to claim 1, wherein the water outlet is configured to move horizontally in parallel with respect to the substrate processing area. **Claim 16** A method for cleaning a substrate, comprising: emitting ultraviolet rays from a lamp in an irradiation area; receiving a supply of ozone water at an inlet of a water deflector disposed at a distance below the lamp; discharging the ozone water irradiated with ultraviolet rays by the lamp at an outlet of the water deflector into a substrate processing area below the water deflector; and the water deflector defining a water flow path between the inlet and the outlet, the water flow path extending within the irradiation area. **Claim 17** The method according to claim 16, further comprising horizontally moving the outlet in parallel with respect to the substrate processing area while discharging the ultraviolet ray-irradiated ozone water. **Claim 18** The method according to claim 16, further comprising discharging the ultraviolet ray-irradiated ozone water onto a substrate within the substrate processing area. **Claim 19** The method according to claim 18, further comprising rotating the substrate while discharging the ultraviolet ray-irradiated ozone water onto the substrate. **Claim 20**: The method according to claim 18, further comprising shielding the substrate from ultraviolet rays while discharging the ultraviolet ray-irradiated ozone water onto the substrate.

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