Improved half-angle nozzle

Abstract

An implementation of the present disclosure provides an apparatus for improving gas distribution during thermal treatment. An implementation of the present disclosure provides an apparatus for thermally treating a substrate. The apparatus includes a main body, an angled gas source assembly, and a gas injection channel. The gas injection channel has a first half-angle and a second half-angle. The first half-angle is different from the second half-angle. Using a modified side gas assembly in a processing chamber to direct gas toward the edge of the substrate advantageously controls growth uniformity throughout the substrate (i.e., from the center to the edge). Surprisingly, directing gas through a gas channel having an uneven half-angle significantly increases reactions at or near the edge of the substrate, thereby resulting in improved overall thickness uniformity of the substrate.

Description

Technical Field

[0001] The present disclosure relates generally to a semiconductor processing tool and, more particularly, to a reactor with improved gas flow distribution. Background Art

[0002] Semiconductor substrates are processed for a wide range of applications, including the fabrication of integrated devices and microdevices. One method of processing a substrate includes growing an oxide layer on the upper surface of a substrate within a processing chamber. The oxide layer can be deposited by exposing the substrate to oxygen and hydrogen gases while heating the substrate using a radiant heat source. Oxygen radicals strike the surface of the substrate, forming a layer, such as a silicon dioxide layer, on the silicon substrate.

[0003] Current process chambers for rapid thermal oxidation (RTO) have limited growth control, resulting in poor process uniformity. Conventionally, a rotatable substrate support rotates the substrate while reactant gases are introduced horizontally parallel to the substrate, causing film deposition on the substrate mounted on the substrate support. Current gas inlet designs cause gases to reach the substrate and deposit unevenly across the substrate. Limited growth control due to current gas inlet designs results in higher growth at the center of the substrate and poor growth at the edges.

[0004] Thus, there is a need for improved gas flow distribution that provides growth control to achieve more uniform growth across the substrate. Summary of the Invention

[0005] An implementation of the present disclosure provides an apparatus for improving gas distribution during thermal processing. One implementation of the present disclosure provides an apparatus for thermally processing a substrate. The apparatus includes a main body, an angled protrusion, and a gas injection channel. The gas injection channel has a first half-angle and a second half-angle. The first half-angle is different from the second half-angle.

[0006] Another embodiment of the present disclosure provides an apparatus for processing a substrate, the apparatus comprising a chamber body defining a processing volume and a substrate support member disposed within the processing volume. The substrate support member has a substrate supporting surface. The apparatus also comprises a gas source protrusion coupled to an inlet of the chamber body, an exhaust assembly coupled to an outlet of the chamber body, and a side gas assembly coupled to a sidewall of the chamber body. The side gas assembly includes a gas injection channel. The gas injection inlet comprises a first half-angle and a second half-angle. The first half-angle is different from the second half-angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Therefore, in order to enable a detailed understanding of the manner in which the above-mentioned features of the present disclosure are employed, a more particular description of the present disclosure, briefly summarized above, may be made with reference to various implementations, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings illustrate only typical implementations of the present disclosure and are not to be considered as limiting the scope of the present disclosure, as the present disclosure may admit to other equally effective implementations.

[0008] Figure 1A is a schematic cross-sectional representation of a thermal processing chamber that may be used to practice implementations of the present disclosure.

[0009] Figure 1B is a schematic cross-sectional top view of a thermal processing chamber according to one implementation of the present disclosure.

[0010] Figure 2A is a schematic cross-sectional top view of a gas injector according to one implementation of the present disclosure.

[0011] Figure 2B and Figure 2C is a three-dimensional schematic diagram of a gas injector according to the present disclosure.

[0012] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one implementation may be beneficially utilized on other implementations without further recitation. DETAILED DESCRIPTION

[0013] Figure 1A 1 is a schematic cross-sectional representation of a thermal processing chamber 100 that can be used to practice implementations of the present disclosure. The thermal processing chamber 100 generally includes a lamp assembly 110, a chamber assembly 130 defining a processing volume 139, and a substrate support 138 disposed in the processing volume 139. The processing chamber 100 is capable of providing a controlled thermal cycle that heats a substrate 101 for use in processes such as, for example, thermal annealing, thermal cleaning, thermal chemical vapor deposition, thermal oxidation, and thermal nitridation, among others.

[0014] The lamp assembly 110 can be positioned relatively above the substrate support 138 to supply heat to the processing volume 139 via the quartz window 114. The quartz window 114 is disposed between the substrate 101 and the lamp assembly 110. In some implementations, the lamp assembly 110 can additionally or alternatively be positioned relatively below the substrate support 138. Note that the terms "above" or "below" as used in this disclosure do not refer to absolute directions. The lamp assembly 110 is configured to accommodate a heating source 108, such as a plurality of tungsten halogen lamps for providing regulated infrared heating to the substrate 101 disposed on the substrate support 138. The plurality of tungsten halogen lamps can be arranged in a hexagonal arrangement. The heating source 108 can be connected to a controller 107, which can control the energy level of the heating source 108 to achieve a uniform or regulated heating profile for the substrate 101. In one example, the heating source 108 can rapidly heat the substrate 101 at a rate of from about 50°C / s to about 280°C / s.

[0015] The substrate 101 can be heated to a temperature ranging from about 550 degrees Celsius to about less than 700 degrees Celsius. The heating source 108 can provide zoned heating (temperature tuning) of the substrate 101. Temperature tuning can be performed to change the temperature of the substrate 101 at certain locations while not affecting the temperature of the rest of the substrate. A slit valve 137 can be provided on the susceptor ring 140 to allow a robot to transfer the substrate 101 into and out of the processing volume 139. The substrate 101 can be placed on a substrate support 138, which can be configured to move vertically and rotate about a central axis 123. A gas inlet 131 can be provided above the susceptor ring 140 and connected to a gas source 135 to provide one or more process gases to the processing volume 139. A gas outlet 134 formed on a side of the susceptor ring 140 opposite the gas inlet 131 is adapted to be in fluid communication with an exhaust assembly 124 of a pump system 136. The exhaust assembly 124 defines an exhaust volume 125 that is in fluid communication with a processing volume 139 via an outlet port 134 .

[0016] In one implementation, one or more side ports 122 can be formed above the susceptor ring 140 between the gas inlet 131 and the gas outlet 134. The side ports 122, the gas inlet 131, and the gas outlet 134 can be disposed at substantially the same level. That is, the side ports 122, the gas inlet 131, and the gas outlet 134 can be at substantially the same level. As will be discussed in more detail below, the side ports 122 are connected to a side gas source configured to improve the uniformity of gas distribution near the edge region of the substrate 101.

[0017] Figure 1B FIG. 1 is a schematic cross-sectional top view of a thermal processing chamber 100 according to one implementation of the present disclosure. Figure 1BAs shown, the gas inlet 131 and the gas outlet 134 are disposed on opposite sides of the processing volume 139. The gas inlet 131 and the gas outlet 134 may each have a linear or azimuthal width approximately equal to the diameter of the substrate support 138.

[0018] In one embodiment, the gas source 135 may include a plurality of gas sources, such as a first gas source 141 and a second gas source 142, each configured to provide a process gas connected to an injection cartridge 149. Gas flows from the first gas source 141 and the second gas source 142 through the injection cartridge 149 and the gas inlet 131 into the processing volume 139. In one embodiment, the injection cartridge 149 has an elongated channel 150 and two inlets 143, 144 formed at opposite ends of the elongated channel 150. A plurality of injection holes 151 are distributed along the elongated channel 150 and are configured to inject the primary gas flow 145 toward the processing volume 139. The dual inlet design of the cartridge 149 improves the uniformity of the gas flow in the processing volume 139. The main gas flow 145 may include 30% to 50% hydrogen by volume and 50% to 70% oxygen by volume and have a flow rate ranging from about 20 standard liters per minute (slm) to about 50 slm. The flow rate is based on a substrate 101 having a diameter of 300 mm, which results in a flow rate ranging from about 0.028 slm / cm 2 to about 0.071slm / cm 2 Varying flow rate.

[0019] A primary gas flow 145 is directed from the gas inlet 131 toward the gas outlet 134 and to the pump 136, which is the vacuum source for the chamber 100. In one implementation, the exhaust volume 125 of the exhaust assembly 124 is configured to expand the processing volume 139, thereby reducing the geometric effects of the chamber structure on the primary gas flow 145. The pump 136 can also be used to control the pressure of the processing volume 139. In one exemplary operation, the pressure inside the processing volume is maintained at about 1 Torr to about 19 Torr, such as between about 5 Torr and about 15 Torr.

[0020] In one implementation, a gas injector 147 is coupled to the susceptor ring 140 such that gas flows through the side port 122 along a side gas flow 148 to the processing volume 139. The gas injector 147 is in fluid communication with a gas source 152 via a flow regulator 146, which is configured to control the flow rate of the side gas flow 148. The gas source 152 may include one or more gas sources 153, 154. In one illustrative example, the gas source 152 is a remote plasma source (RPS) that generates hydrogen radicals into the side port 122. During the process, the gas injector 147 is configured to inject hydrogen radicals into the processing volume 139. The hydrogen radicals introduced from the gas injector 147 increase the reaction rate along the edge of the substrate 101, resulting in an oxide layer having improved thickness uniformity. The side gas flow 148 can have a flow rate ranging from about 5 slm to about 25 slm. For a substrate having a diameter of 300 mm, the flow rate is about 0.007 slm / cm 2 to about 0.035slm / cm 2 The composition and flow rate of the side gas stream 148 are important factors in forming an oxide layer with improved thickness uniformity.

[0021] exist Figure 1B In the illustrated embodiment, the gas injector 147 is a structure having a funnel-shaped opening that flares toward the processing volume 139. That is, the side port 122 has an inner diameter that gradually increases toward the substrate 101. The gas injector 147 is adapted to direct a majority of the side gas flow 148 toward the edge of the substrate 101, which is shaped like a hollow sector or a hollow flat cone. The edge of the substrate 101 can refer to a peripheral region measured from 0 mm to 15 mm (e.g., 10 mm) from the edge of the substrate 101. Because the funnel-shaped structure of the gas injector 147 flares a majority of the side gas flow 148 toward the edge of the substrate 101, gas exposure of the substrate 101 is increased at or near the edge region. In one embodiment, the inner surface 179 of the gas injector 147 is configured such that the inner surface extends along a direction 189 that is substantially tangential to the edge of the substrate 101 or substantially tangential to the edge of the substrate supporting surface of the substrate support 138.

[0022] Furthermore, as the substrate 101 rotates in the counterclockwise direction 197, the gas flows over the substrate 101, resulting in higher growth at the edge of the substrate 101. Figure 1B While the substrate 101 is shown rotating in a counterclockwise direction, the substrate 101 can be rotated in a clockwise direction without losing the benefits from the side gas flow 148. The gas velocity of the side gas flow 148 and the gas flow pattern in the processing volume 139 can be adjusted by one or more of the flow rate of the side gas flow 148, the rotation speed of the substrate 101, and the spread angle of the gas injector 147. Controlling aspects of the side gas flow 148 prevents gas flow non-uniformity that could affect how the side gas flow 148 reacts with the main gas flow 145 and the substrate 101. As a result, the thickness profile at the edge of the substrate is improved.

[0023] The gas injector 147 can be made of any suitable material such as quartz, ceramic, aluminum, stainless steel, steel, or the like. To further increase the effect of the side gas flow at the edge of the substrate 101, the gas injector 147 can be constructed with one or more gas channels directed toward the edge of the substrate 101. Figure 2A is a schematic cross-sectional top view of a gas injector 247 according to one implementation of the present disclosure.

[0024] exist Figure 2A In one embodiment, the gas injector 247 is an elongated structure having a gas passage 249 formed therein. The gas injector 247 has a body 230 and a protrusion 205. The protrusion 205 may be triangular in shape. The protrusion 205 may be a gas source assembly. In one embodiment, the protrusion 205 includes an angled opening 246 with a circular inlet 216 (e.g., Figure 2B ), angled side 202, first facet 218, and second facet 204. In one implementation, angled opening 246 is rectangular. In one implementation, first facet 218 is parallel to second facet 204. Second facet 204 can be twice the length of first facet 218. Second facet can be between 0.040 and 0.048 inches.

[0025] In one embodiment, the body 230 is rectangular with rounded edges. The body 230 has a first side 232 opposite a second side 234. In one embodiment, the first side 232 and the second side 234 are substantially the same length. In one embodiment, the first side 232 and the second side 234 are parallel. Figure 2B 2, the body has a third side 224, a fourth side 222, a fifth side 226, and a sixth side 282. A first facet 218 can connect the angled side 202 to the fifth side 226. A second facet can connect the angled opening 246 to the fifth side 226. A protrusion 205 can connect to the fifth side 226. The angled opening 246 can be perpendicular to the angled side 202.

[0026] The gas injector can include an elongated channel having a cross-section of any desired shape, such as a rectangular, square, circular, polygonal, hexagonal, or any other suitable shape. The gas injector 247 is adapted to direct a majority of the side gas flow 148 toward the edge of the substrate 101, which is in the shape of a hollow sector or a hollow flat cone. The gas channel 249 includes two inner surfaces 279, 280. In one embodiment, the inner surfaces 279, 280 are configured such that each inner surface extends substantially tangentially to an edge of the substrate 101 or substantially tangentially to an edge of the substrate supporting surface of the substrate support 138. The inner surfaces 279, 280 extend from the angled opening 246 to a curved surface 282. The curved surface 282 is adjacent to the substrate 101 and on the opposite side of the protrusion 205.

[0027] Gas passage 249 is angled through side port 122 ( Figure 1B ) to the processing volume 139( Figure 1B ) provides a side airflow 248. The side airflow 248 flows along a flow path that adjusts the edge profile of the substrate 101 being processed. Advantageously and surprisingly, changing the half angle of the gas channel 249 so that the airflow pattern of the side airflow 248 has an uneven lateral expansion produces a more uniform thickness profile of the material deposited on the substrate 101. Therefore, the gas channel 249 has two different half angles 250a and 250b. One half angle 250a, 250b can be between 29.5° and 30.5°, while the other half angle 250a, 250b can be between 31.8° and 32.8°. The half angles 250a and 250b are angles measured using the central axis 210 of the substrate 101 and the central intersection 220 of the gas channel 249. The central axis 210 is a line extending from the center of the substrate 101 to the opening of the gas channel 249. The central axis 210 is parallel to the first side 232. In one implementation, the central axis 210 is a line parallel to the first side 232 that extends through a point 212. The point 212 is located on the inner edge of the angled opening 246. The angled opening 246 has a circular entrance 216 (e.g., Figure 2B ). The circular inlet 126 leads to the expanded interior space 214. In one embodiment, the expanded interior space 214 is rectangular. In one embodiment, point 212 is at the intersection of the angled opening 246 and the interior space 214. In one embodiment, the expanded interior space 214 is connected to the inlet channel 249. The central intersection 220 is the midpoint of the opening of the gas channel 249. The central intersection 220 is defined by a line parallel to the fifth side 226 and intersecting the point where the first facet 218 connects to the angled side 202.

[0028] The gas injector 247 has an angled gas source protrusion 205 that is connected to the gas source 152. In one embodiment, the angled gas source protrusion 205 is triangular in shape. In one embodiment, the opening of the angled gas source protrusion 205 is disposed at an angle 242 between approximately 137° and 141°. In one embodiment, the gas channel 249 is configured such that, after exiting the gas channel 249, the gas or gas radicals flow in a direction substantially tangential to the edge of the substrate 101 or substantially tangential to the edge of the substrate supporting surface of the substrate support 138. It is contemplated that the angle of the gas channel 249 can be adjusted so that the side gas flow 248 flows toward the center of the substrate 101 (or substrate support 138), near the periphery of the substrate 101 (or substrate support 138), or at any desired location spatially distributed on the substrate 101 (or substrate support 138).

[0029] Regardless of whether the side gas flow 248 (gas or gas radicals) flows tangentially to or close to the edge of the substrate 101 (or the edge of the substrate supporting surface of the substrate support 138), the gas or gas radicals significantly promote the reaction rate along the edge of the substrate 101. In the process, the gas injector 247 is configured to provide side gas flow 248 at different angles to the substrate 101. Surprisingly, providing side gas at or near the edge of the substrate 101 through the gas channel 249 with a non-uniform half angle allows the oxide layer to have improved thickness uniformity along the edge of the substrate 101.

[0030] In one exemplary implementation, the gas injector 247 is configured to have a gas passage 249 directed toward the gas injection side of the processing chamber 100 (e.g., the slit valve 137). That is, the gas passage 249 extends in a direction toward the gas injection side of the processing chamber. In this manner, a majority of the gas flows along the side gas flow 248 toward the gas injection side of the processing chamber 100 and meets the substrate 101 (or substrate support surface of the substrate support 138) at or near the edge of the substrate 101 (or substrate support surface of the substrate support 138) from the injection cartridge 149 ( Figure 1B ) to react with the processed gas coming out.

[0031] Figure 2B and Figure 2C2 is a three-dimensional schematic diagram of a gas injector 247 according to the present disclosure. The gas injector 247 is configured to direct a majority of the gas or gas radicals along a side gas flow toward the gas injection side (e.g., slit valve 137) and the gas exhaust side (e.g., pump system 136) of the processing chamber 100, respectively. Additionally or alternatively, the gas channel 249 can be configured such that the side gas flow 248 flows tangentially to the edge of the substrate 101 (or the edge of the substrate supporting surface of the substrate support 138), or in a direction proximate to the edge of the substrate 101.

[0032] Gas injector 247 includes sides 226, 232, 234, 282, 224, and 222. First side 232 opposes second side 234. In one embodiment, first side 232 is parallel to and substantially the same length as second side 234. First curved surface 236 is disposed between first side 232 and third side 224. Third side 224 is disposed orthogonally to first side 232. Second curved surface 240 is disposed between second side 234 and third side 224. Third curved surface 238 is disposed between first side 232 and fourth side 222. Fourth side 222 is orthogonal to first side 232. Fourth curved surface 228 is disposed between second side 234 and fourth side 222. Third side 224 opposes fourth side 222. Fifth side 226 opposes sixth side 282. In one embodiment, sixth side 282 is curved. The radius of curvature of sixth side 282 may be between approximately 8 and approximately 9 inches. The third side 224 is on the same plane as the angled gas source protrusion 205. The gas channel 249 is provided on the sixth side 282 facing the substrate 101. Advantageously, the first side 232 and the second side 234 are substantially perpendicular to the fourth side 222, thereby allowing for a stronger adhesive seal within the chamber 100. Figure 2C As can be seen in FIG, one implementation can optionally include facets 204 and 218. In one implementation, angled gas source protrusion 205 is connected to fifth side 226 via facets 204 and 218. In one implementation, angled side 202 and angled opening 246 are directly connected to fifth side 226. The curvature of the sixth side advantageously promotes more uniform identification of the gas and reduces turbulent gas flow toward substrate 101 by following the curvature of substrate 101.

[0033] Although thermal processing chambers are discussed in this application, implementations of the present disclosure may be used in any processing chamber where uniform gas flow is desired.

[0034] Benefits of the present disclosure include the use of an improved side gas assembly in a processing chamber to direct gas toward the edge of a substrate in order to control growth uniformity across the substrate (i.e., from the center to the edge). The side gas assembly has angled gas inlets configured to point toward the gas injection side of the processing chamber (e.g., a slit valve) and / or the gas exhaust side of the processing chamber (e.g., a pump system). Specifically, it has been surprisingly observed that directing gas through gas channels having non-uniform half angles results in a uniform growth pattern. The reaction at or near the edge of the substrate will be significantly increased in the process, resulting in improved thickness uniformity along the edge of the substrate and improved overall thickness uniformity of the substrate.

[0035] While the foregoing is directed to implementations of the present disclosure, other and further implementations of the disclosure may be devised without departing from the basic scope thereof, the scope of which is to be determined by the claims which follow.

Claims

1. An apparatus for heat treating a substrate, comprising: A subject, wherein the subject comprises: First side; a second side surface, opposite to the first side surface, wherein the first side surface and the second side surface are substantially the same length; a third side surface, perpendicular to the first side surface; a first curved surface extending between the first side surface and the third side surface; a second curved surface extending between the third side surface and the second side surface; a fourth side surface, perpendicular to the second side surface; a third curved surface extending between the first side surface and the fourth side surface; and a fourth curved surface extending between the fourth side surface and the second side surface, wherein the fourth side surface is opposite to the third side surface; Angled protrusions; and Gas injection channel, including: first half angle; and A second half angle, wherein the first half angle is different from the second half angle.

2. The apparatus of claim 1 , wherein the body comprises: a fifth side surface, perpendicular to the first side surface; and A sixth side surface is orthogonal to the first side surface, wherein the sixth side surface is opposite to the fifth side surface.

3. The apparatus of claim 2, wherein the angled protrusion is provided on the fifth side, and wherein the gas injection channel is provided on the sixth side. The apparatus of claim 1 , wherein the angled protrusions are triangular in shape.

5. The apparatus of claim 2, wherein the angled protrusion comprises: First facet; and Second facet.

6. The apparatus of claim 5, wherein the angled protrusion further comprises a circular inlet.

7. The apparatus of claim 6, wherein the circular inlet is in fluid communication with the gas injection channel.

8. The apparatus of claim 1, wherein the gas injection channel provides a gas flow along a flow path located at a distance of 5 mm to 10 mm from a tangent line to a substrate supporting surface parallel to the flow path.

9. The apparatus of claim 1, wherein the first half angle is between 29.5° and 30.5°, and wherein the second half angle is between 31.8° and 32.8°.

10. The apparatus of claim 1, wherein the gas injection channel is a flat, funnel-shaped structure that opens toward the processing volume.

11. An apparatus for processing a substrate, comprising: a chamber body defining a processing volume; a substrate support disposed in the processing volume, wherein the substrate support has a substrate supporting surface; an angled gas source protrusion coupled to the inlet of the chamber body; an exhaust assembly coupled to the outlet of the chamber body; and a side gas assembly coupled to a sidewall of the chamber body, the side gas assembly comprising: A subject, wherein the subject comprises: First side; a second side surface, opposite the first side surface, wherein the first side surface and the second side surface are substantially the same length; a third side surface, perpendicular to the first side surface; a first curved surface extending between the first side surface and the third side surface; a second curved surface extending between the third side surface and the second side surface; a fourth side surface, perpendicular to the second side surface; a third curved surface extending between the first side surface and the fourth side surface; and a fourth curved surface extending between the fourth side surface and the second side surface, wherein the fourth side surface is opposite to the third side surface; Gas injection channel, including: first half angle; and A second half angle, wherein the first half angle is different from the second half angle.

12. The apparatus of claim 11, wherein the body comprises: a fifth side surface, perpendicular to the first side surface; and A sixth side surface is orthogonal to the first side surface, wherein the sixth side surface is opposite to the fifth side surface.

13. The apparatus of claim 12, wherein the angled gas source protrusion is disposed on the fifth side, and wherein the gas injection channel is disposed on the sixth side.

14. The apparatus of claim 11, wherein the angled air source protrusion comprises: First facet; and Second facet.

15. The apparatus of claim 14, wherein the angled gas source protrusion further comprises a circular inlet.

16. The apparatus of claim 15, wherein the circular inlet is in fluid communication with the gas injection channel.

17. The apparatus of claim 11, wherein the side gas assembly provides a gas flow along a flow path located at a distance of 5 mm to 10 mm from a tangent line to the substrate support surface parallel to the flow path.

18. The apparatus of claim 11, wherein the first half angle is between 29.5° and 30.5°, and wherein the second half angle is between 31.8° and 32.8°.

19. The apparatus of claim 11, wherein the gas injection channel is a funnel-shaped structure that opens toward the processing volume.

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