Honeycomb injector with dielectric window for substrate processing system

Abstract

An assembly for a substrate processing chamber includes: a quartz dielectric window configured to be disposed in an upper surface of the substrate processing chamber; a recess in the quartz dielectric window, the recess including a first opening extending through the quartz dielectric window; and a gas injector assembly including a gas injector. The gas injector assembly is disposed within the recess such that the gas injector extends through the first opening. The gas injector is composed of solid yttrium oxide and / or includes an outer surface having an yttrium oxide coating.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 712,415, filed on July 31, 2018. The entire disclosure of the above-referenced application is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to gas injectors for substrate processing systems. Background Art

[0004] The background description provided here is intended to generally introduce the context of the present disclosure. To the extent described in this background section, the work of the inventors presently mentioned and aspects of the description that may not have qualified as prior art at the time of filing are not admitted, either explicitly or implicitly, as prior art against the present disclosure.

[0005] During the manufacture of substrates such as semiconductor wafers, etching and deposition processes can be performed within a process chamber. The substrate is positioned on a substrate support such as an electrostatic chuck (ESC) or a susceptor within the process chamber. Process gases are introduced and a plasma is ignited within the process chamber.

[0006] The process chamber may include a transformer-coupled plasma (TCP) reactor coil. A radio frequency (RF) signal generated by a power supply is provided to the TCP reactor coil. A dielectric window is incorporated into the upper surface of the process chamber. The dielectric window maintains the vacuum seal of the process chamber while allowing the RF signal to be transmitted from the TCP reactor coil to the interior of the process chamber. The RF signal excites gas molecules within the process chamber to generate plasma. Summary of the Invention

[0007] An assembly for a substrate processing chamber includes: a quartz dielectric window configured to be disposed in an upper surface of the substrate processing chamber; a recess in the quartz dielectric window, the recess including a first opening extending through the quartz dielectric window; and a gas injector assembly including a gas injector. The gas injector assembly is disposed within the recess such that the gas injector extends through the first opening. The gas injector is composed of solid yttrium oxide and / or includes an outer surface having an yttrium oxide coating.

[0008] Among other features, the gas injector corresponds to a gas injector having a honeycomb structure including a plurality of gas outlets. The assembly further includes a socket disposed in the recess, the socket including a second opening and the gas injector extending through the second opening. The second opening corresponds to a bayonet opening. The socket comprises at least one of plastic and quartz. The assembly further includes a nut assembly disposed to secure the gas injector assembly within the second opening. The nut assembly is configured for a twist-lock operation. The assembly further includes a radio frequency shield disposed between the nut assembly and the gas injector.

[0009] Among other features, the assembly further includes a seal disposed between the RF shield and a gas connection block of the gas injector assembly. The RF shield includes a slot configured to receive the body of the nut assembly. The slot is disposed above the socket. The gas injector includes a flange disposed within the second opening, and a lower flange of the RF shield is positioned above the flanges of the gas injector and the socket.

[0010] Among other features, the assembly further includes a seal disposed in the recess between the gas injector and the dielectric window. The seal is an O-ring. The assembly further includes a socket disposed in the recess and including a second opening, the gas injector extending through the second opening, and the gas injector including a flange disposed within the second opening. The height of the flange is substantially equal to at least one of the depth of the first opening and the height of the socket. The upper surface of the flange is flush with the upper surface of the socket.

[0011] An assembly for a substrate processing chamber includes: a quartz dielectric window configured to be disposed in an upper surface of the substrate processing chamber; a central recess in the quartz dielectric window, the central recess including a first opening extending through the quartz dielectric window; a socket disposed in the central recess including a second opening; and a gas injector assembly including a gas injector. The gas injector assembly is disposed within the central recess such that the gas injector extends through the second opening. The gas injector includes a plurality of gas outlets and is composed of solid yttrium oxide and / or includes an outer surface having an yttrium oxide coating.

[0012] In other features, the assembly further includes a nut assembly arranged to secure the gas injector assembly within the second opening. The gas injector includes a flange arranged within the second opening. The flange has a height substantially equal to at least one of a depth of the first opening and a height of the socket, such that an upper surface of the flange is flush with an upper surface of the socket.

[0013] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present disclosure will be more fully understood through the detailed description and accompanying drawings, in which:

[0015] Figure 1A is an example of a substrate processing system including a dielectric window according to the present disclosure;

[0016] Figure 1B and 1C An exemplary dielectric window according to the present disclosure is shown;

[0017] Figure 1D and 1E An exemplary gas injector assembly according to the present disclosure is shown; and

[0018] Figure 2A 、 2B , 2C and 2D illustrate gas injectors according to the present disclosure.

[0019] In the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0020] A substrate processing system may include a dielectric window incorporated into an upper surface of a processing chamber. A gas injector assembly is disposed in an opening in the dielectric window to inject a processing gas into the processing chamber. In some examples, the dielectric window includes a central recess and a socket disposed in the recess. The socket includes a bayonet-type opening configured to receive the gas injector assembly.

[0021] The dielectric window can be made of a material such as ceramic or quartz and may or may not be coated with another material. The gas injector assembly includes a gas injector, which may include one or more materials, such as ceramic, quartz, yttrium oxide, etc., and may or may not be coated with another material. Different gas injector assemblies can be configured to engage with different types of dielectric windows and / or dielectric windows having different recess designs, different sizes, etc. For example, a quartz dielectric window may be more brittle (e.g., relative to ceramic) and therefore easily broken by the insertion of the gas injector assembly. Therefore, the configuration of the recess, bayonet and / or other features may need to be adjusted, and the gas injector may need to be modified to accommodate the adjusted configuration. In other examples, the effectiveness of the seal between the gas injector assembly and the dielectric window may depend on the materials and configuration of the gas injector assembly and the dielectric window. An exemplary dielectric window and a gas injector assembly having a honeycomb configuration are described in more detail in U.S. Patent No. 9,947,512 (which is incorporated herein by reference in its entirety). As described therein, a gas injector having a honeycomb configuration reduces center defects associated with substrate processing and improves yield. As used herein, the term "honeycomb" means that the gas injector has a plurality of gas outlets, as described in more detail below.

[0022] In some examples, a quartz dielectric window can be configured to interface with a gas injector assembly containing a gas injector made of quartz, ceramic, aluminum, stainless steel, alumina, silicon nitride, or the like. Conversely, a ceramic dielectric window can be configured to interface with a gas injector assembly containing a yttria gas injector. However, conventional designs do not include quartz dielectric windows configured to interface with gas injector assemblies containing solid yttria gas injectors or non-yttria gas injectors with a yttria coating. For example, because high-purity quartz and yttria are relatively brittle, it is difficult to prevent the quartz dielectric window and yttria gas injector from breaking during installation while maintaining an adequate seal between the gas injector assembly and the dielectric window. For example, existing quartz dielectric windows use clips to secure the quartz gas injector, which does not provide an adequate seal with solid yttria and / or yttria-coated gas injectors.

[0023] A quartz dielectric window and gas injector assembly according to the present disclosure is configured for use with a gas injector assembly comprising a gas injector composed of solid yttria or a non-yttria material having an yttria coating. The dielectric window includes a central recess and a socket configured to accommodate an adapter (e.g., a bayonet adapter) and a nut assembly for securing the gas injector assembly. The adapter facilitates and secures compression of an O-ring seal between the gas injector and the dielectric window without damaging the gas injector or the dielectric window. Furthermore, yttria is less susceptible to flaking and other particle generation defects than other gas injector materials, resulting in fewer defects in processed substrates.

[0024] Now refer to Figure 1A , shows an example of a substrate processing system 10 according to the present disclosure. The substrate processing system 10 includes a coil drive circuit 11. In some examples, the coil drive circuit 11 includes an RF source 12 and a tuning circuit 13. The tuning circuit 13 can be directly connected to one or more inductive TCP coils 16. Alternatively, the tuning circuit 13 can be connected to the one or more coils 16 through an optional reversible circuit 15. The tuning circuit 13 tunes the output of the RF source 12 to a desired frequency and / or a desired phase, matches the impedance of the coils 16, and distributes power among the TCP coils 16. The reversible circuit 15 is used to selectively switch the polarity of the current passing through the one or more TCP coils 16.

[0025] A plenum chamber 20 can be positioned between the TCP coil 16 and the dielectric window 24 to control the temperature of the dielectric window 24 using a flow of hot and / or cold air. The dielectric window 24 is positioned along one side of a process chamber 28. The process chamber 28 also includes a substrate support (or pedestal) 32. The substrate support 32 can include an electrostatic chuck (ESC), a mechanical chuck, or other types of chucks. A process gas is supplied to the process chamber 28, and a plasma 40 is generated within the process chamber 28. The plasma 40 etches the exposed surface of the substrate 34. An RF source 50 and a bias matching circuit 52 can be used to bias the substrate support 32 during operation to control the ion energy.

[0026] A gas delivery system 56 can be used to supply a process gas mixture to the process chamber 28. The gas delivery system 56 can include process and inert gas sources 57; a gas metering system 58, such as valves and mass flow controllers; and a manifold 59. A gas delivery system 60 can be used to deliver gas 62 to the plenum chamber 20 via valve 61. The gas can include cooling gas (air) for cooling the TCP coil 16 and dielectric window 24. A heater / cooler 64 can be used to heat / cool the substrate support 32 to a predetermined temperature. An exhaust system 65 includes a valve 66 and a pump 67 to remove reactants from the process chamber 28 by purging or evacuating.

[0027] The controller 54 can be used to control the etching process. The controller 54 monitors system parameters and controls the delivery of gas mixtures, ignition, maintenance, and extinguishing of plasma, removal of reactants, supply of cooling gases, and the like. In addition, as described in detail below, the controller 54 can control various aspects of the coil drive circuit 11, the RF source 50, and the bias matching circuit 52. For example, a processing chamber using a TCCT matching network with switched capacitors is shown and described in commonly assigned U.S. Patent No. 9,515,633 (which is incorporated herein by reference in its entirety).

[0028] The temperature controller 68 can be connected to a plurality of heating elements 70, such as thermal control elements (TCEs), disposed in the substrate support 32. The heating elements 70 can include, but are not limited to, macro heating elements corresponding to individual zones in a multi-zone heating plate and / or an array of micro heating elements disposed across multiple zones of the multi-zone heating plate. The temperature controller 68 can be used to control the plurality of heating elements 70 to control the temperature of the substrate support 32 and the substrate 34, as described in more detail below.

[0029] The dielectric window 24 according to the present disclosure is a quartz dielectric window configured to receive a solid yttria and / or yttria-coated gas injector ( Figure 1A ), as described in more detail below.

[0030] Now refer to Figure 1B 、 1C , 1D, and 1E, show in more detail an exemplary dielectric window 100 and a gas injector assembly 104 including a gas injector 108 comprised of yttria in accordance with the principles of the present disclosure. For example, the gas injector 108 can be comprised of solid yttria, or can include a non-yttria material with an yttria coating. In other words, the outer surface of the gas injector 108 can include an yttria coating. The dielectric window 100 is comprised of quartz (e.g., high purity quartz). The dielectric window 100 includes a central recess 112 configured to accommodate the gas injector 108. The central recess 112 includes an opening 116 extending through the dielectric window 100. Figure 1B and Figure 1C shows a view of the dielectric window 100, and Figure 1D and Figure 1E An assembly comprising a dielectric window 100 and a gas injector assembly 104 mounted within the dielectric window 100 is shown.

[0031] The gas injector assembly 104 is disposed within the central recess 112 such that the gas injector 108 extends through the opening 116 of the dielectric window 100. For example, a socket 120 (e.g., an annular socket, such as a disk socket) is disposed in the central recess 112. The socket 120, which may be composed of plastic, quartz, or another dielectric material, includes an opening 124 (e.g., a bayonet-style opening) configured to receive the gas injector assembly 104.

[0032] A gas injector 108 (e.g., a gas injector having a honeycomb configuration including a plurality of gas outlets 128) extends through opening 124 and opening 116 and into process chamber 28. A nut assembly 132 secures gas injector assembly 104 within opening 124. For example, nut assembly 132 may be configured for a twist-lock operation, such as described in U.S. Patent No. 9,947,512. An RF shield 136 is disposed between nut assembly 132 and gas injector 108. For example, RF shield 136 may comprise a metal such as copper, aluminum, etc., and / or may be coated with a metal (e.g., silver).

[0033] The gas injector assembly 104 includes one or more O-rings to provide a gas seal between the various components of the gas injector assembly 104. For example, an O-ring 140 is disposed between the gas injector 108 (e.g., in a groove) and the dielectric window 100. An O-ring 144 is disposed between the RF shield 136 and the gas connection block 148. An O-ring 152 is disposed between the gas injector 108 and the gas connection block 148.

[0034] The gas injector 108 includes a flange (e.g., an annular flange) 156 configured to secure the gas injector 108 within the socket 120 of the dielectric window 100. Because yttrium oxide is brittle and more easily damaged, the height / depth of the flange 156 is greater than that of gas injectors comprising materials other than yttrium oxide, where the flange 156 includes a groove for the O-ring 140 and may rupture under pressure. For example, the vertical height of the flange 156 can be substantially equal to the depth of the opening 112 and the height of the socket 120 (e.g., within 0.05 inches or 1.25 mm). By way of example only, the height of the flange 156 is 0.5 inches (+ / - 0.05 inches) or 12.7 mm. Thus, the upper surface of the flange 156 is flush with the upper surface of the socket 120.

[0035] The RF shield 136 includes a slot 160 configured to receive a body 164 of the nut assembly 132. For example, the slot 160 is disposed above (ie, not within) the socket 120. Additionally, a lower flange 168 of the RF shield 136 is above the flange 156 and the socket 120.

[0036] Figure 2A 、 2B , 2C and 2D show alternative views of an exemplary gas injector 200 constructed of yttrium oxide (e.g., solid yttrium oxide or another material having a yttrium oxide coating) in accordance with the principles of the present disclosure. For example, Figure 2A An isometric view of the gas injector 200 is shown. Figure 2B A cross-sectional view of a gas injector 200 is shown. Figure 2C A side view of a gas injector 200 is shown. Figure 2D Shown Figure 2B An enlarged view of feature 204 is shown in FIG.

[0037] The above description is essentially illustrative only and is not intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be realized in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because after studying the drawings, description and appended claims, other modifications will become apparent. It should be understood that, without changing the principle of the present disclosure, one or more steps in the method can be performed in different orders (or simultaneously). In addition, although each of the embodiments is described as having certain features above, any one or more of those features described relative to any embodiment of the present disclosure can be implemented in the features of any one in other embodiments and / or combined with the features of any one in other embodiments, even if the combination is not clearly described. In other words, the embodiments described are not mutually exclusive, and the replacement of one or more embodiments with each other is still within the scope of the present disclosure.

[0038] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "near," "on top of," "above," "below," and "disposed." Unless explicitly described as "direct," when describing the relationship between a first element and a second element in the above disclosure, the relationship can be a direct relationship in which there are no other intervening elements between the first element and the second element, but can also be an indirect relationship in which there are one or more intervening elements (either spatially or functionally) between the first element and the second element. As used herein, the phrase at least one of A, B, and C should be interpreted as meaning a logical (A or B or C) using a non-exclusive logical "or" and should not be interpreted as meaning "at least one of A, at least one of B, and at least one of C."

[0039] In some implementations, the controller is part of a system that can be part of the above examples. Such a system may include semiconductor processing equipment, including one or more processing tools, one or more chambers, one or more platforms for processing and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems can be integrated with electronic devices to control their operation before, during, and after processing semiconductor wafers or substrates. The electronic device can be referred to as a "controller" that can control various components or sub-parts of one or more systems. Depending on the processing requirements and / or type of system, the controller can be programmed to control any process disclosed herein, including the delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow settings, fluid delivery settings, position and operation settings, wafer access tools and other transfer tools and / or load locks connected to or engaged with a particular system.

[0040] Broadly speaking, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receives instructions, issues instructions, controls operations, enables cleaning operations, enables endpoint measurements, and the like. The integrated circuits can include chips in the form of firmware that stores program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software). The program instructions can be instructions delivered to the controller in the form of various separate settings (or program files) that define operating parameters for performing specific processing on or for a semiconductor wafer or for a system. In some embodiments, the operating parameters can be part of a protocol defined by a process engineer to accomplish one or more processing steps during the fabrication of a die of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafers.

[0041] In some embodiments, the controller can be part of or coupled to a computer that is integrated with the system, coupled to the system, networked to the system in other ways, or a combination thereof. For example, the controller can be in the "cloud" or all or part of a fab host computer system, which enables remote access to wafer processing. The computer can enable remote access to the system to monitor the current progress of fabrication operations, review the history of past fabrication operations, review trends or performance indicators from multiple fabrication operations, change parameters of the current process, set processing steps to follow the current process, or start a new process. In some examples, a remote computer (e.g., a server) can provide processing solutions to the system via a network, which can include a local area network or the Internet. The remote computer can include a user interface that enables the input or programming of parameters and / or settings, which are then transmitted from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters can be specific to the type of process to be performed and the type of tool with which the controller is configured to interact or control. Thus, as described above, controllers can be distributed, for example, by including one or more discrete controllers that are networked together and work toward a common purpose (e.g., the processes and controls described herein). An example of a distributed controller for such a purpose would be one or more integrated circuits on the room that communicate with one or more integrated circuits located remotely (e.g., at the platform level or as part of a remote computer) that combine to control the processes on the room.

[0042] Example systems may include, without limitation, plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the fabrication and / or manufacture of semiconductor wafers.

[0043] As described above, depending on the one or more processing steps to be performed by the tool, the controller may communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools throughout the factory, a host computer, another controller, or a tool for material transport that moves wafer containers into and out of tool locations and / or load ports in the semiconductor manufacturing facility.

Claims

1. An assembly for a substrate processing chamber, the assembly comprising: a dielectric window configured to be disposed in an upper surface of the substrate processing chamber; a central recess in the dielectric window, wherein the central recess includes a first opening extending through the dielectric window and a second opening located above the first opening, the second opening including a bayonet-style opening configured to receive a nut assembly; as well as a gas injector, wherein the gas injector is disposed within the central recess such that the gas injector is secured to the dielectric window by the nut assembly and the gas injector extends through the first opening and the second opening, wherein the gas injector (i) consists of solid yttrium oxide, or (ii) comprises an outer surface having a yttrium oxide coating, Wherein the gas injector comprises a flange disposed within the second opening, and wherein a height of the flange is substantially equal to a depth of the second opening.

2. The assembly according to claim 1, wherein The gas injector corresponds to a gas injector having a honeycomb structure including a plurality of gas outlets.

3. The assembly according to claim 1, wherein The dielectric window includes a ceramic dielectric window.

4. The assembly according to claim 1, wherein The dielectric window includes a quartz dielectric window.

5. The assembly of claim 1, further comprising the nut assembly arranged to secure the gas injector within the second opening.

6. The assembly according to claim 5, wherein The nut assembly is configured for a twist-lock operation.

7. The assembly of claim 5, further comprising a radio frequency shield disposed between the nut assembly and the gas injector.

8. The assembly of claim 7, further comprising a seal disposed between the radio frequency shield and a gas connection block of the gas injector assembly.

9. The assembly according to claim 7, wherein The radio-frequency shield includes a slot configured to receive a body of the nut assembly.

10. The assembly according to claim 9, wherein The lower flange of the radio frequency shield is positioned above the flange of the gas injector.

11. The assembly of claim 1 , further comprising a seal disposed in a groove between the gas injector and the dielectric window.

12. The assembly according to claim 11, wherein The seal is an O-ring.

13. The assembly of claim 1, wherein: An upper surface of the flange is flush with an upper surface of the bayonet opening.

14. A gas injector, comprising: a flange configured to secure the gas injector to a central recess of the dielectric window, wherein the central recess includes a first opening and a second opening located above the first opening, wherein the flange is located within the second opening, and wherein the flange includes at least one groove located at a bottom of the flange for receiving a sealing ring; a first set of gas outlets arranged in a honeycomb configuration at the bottom of the gas injector; and a second group of gas outlets, which are arranged radially outside the first group of gas outlets, wherein the height of the flange is substantially equal to the depth of the second opening, and The gas injector is composed of solid yttrium oxide or comprises an outer surface having a yttrium oxide coating.

15. An assembly comprising the gas injector according to claim 14, further comprising: the central recess in the dielectric window, wherein the central recess includes the first opening extending through the dielectric window and the second opening located above the first opening; as well as A nut assembly is arranged to secure the gas injector within the second opening, wherein the second opening includes a bayonet-type opening configured to receive the nut assembly.

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