Divided gas distribution plate for high-power, high-pressure processes

Abstract

To provide a gas distribution plate for a substrate processing system using transformer coupled plasma.SOLUTION: A gas distribution plate includes an outer ring 210 including a stepped interface on a radially inner surface thereof, and N inner rings 220-240 (N represents an integer greater than zero). At least one of the N inner rings is circumferentially split, and includes an inner stepped interface and an outer stepped interface. An outer stepped interface of an inner ring on the radially outside of the N inner rings is placed on the inner stepped interface of the outer ring, and mates with the inner stepped interface of the outer ring. A central portion 250 includes an outer stepped interface 252 on a radially outer surface thereof, and the outer stepped interface is placed on and mates with the inner stepped interface of the inner ring on the radially inside of the N inner rings.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims the benefit of U.S. Provisional Patent Application No. 62 / 966,816, filed on January 28, 2020. The entire disclosure of the application referenced above is incorporated herein by reference.

[0002] This disclosure relates to a substrate processing system, and more particularly to a radially and circumferentially segmented gas distribution plate for a substrate processing system.

Background Art

[0003] [[ID=1^{7}]] The description of "Background Art" provided herein is intended to present the background of the present disclosure generally. The achievements of the inventors named herein within the scope described in the "Background Art" of this specification, as well as aspects of this specification that may not be regarded as prior art at the time of filing, are not recognized as prior art to the present disclosure, either explicitly or implicitly.

[0004] Substrate processing systems may be used to etch films on substrates such as semiconductor wafers. Substrate processing systems typically include a processing chamber, a gas distribution device, and a substrate support. During processing, the substrate is placed on the substrate support. Various gas mixtures may be introduced into the processing chamber, and radio frequency (RF) plasma may be used to activate chemical reactions.

[0005] Current micro - electro - mechanical (MEM) processes may be implemented in substrate processing systems that use transformer - coupled plasma (TCP). In these substrate processing systems, one or more coils are placed outside the chamber. A window is placed between the coil and the chamber. A gas mixture is supplied to the chamber. RF power is supplied to the coil, thereby generating a magnetic field and generating and maintaining RF plasma within the chamber.

[0006] Plasma processing is power-limited due to the large thermal gradient introduced, which can lead to window damage. The window must be made of an inert, RF-permeable material with low dielectric loss characteristics. In addition, the window must not corrode in reaction to typical etching chemicals (e.g., gas mixtures containing halogen species such as fluorine and chlorine). The window must also not degasse undesirable byproducts in reaction to thermal and / or pressure cycles.

[0007] Assuming the above criteria are met, the material selection for windows is generally limited to oxide ceramics, quartz, and some nitride ceramics. Negative aspects of oxide ceramics include high thermal insulation properties combined with a relatively high coefficient of thermal expansion. Oxide ceramics tend to suffer catastrophic failure when subjected to harsh thermal gradients and / or impacts. Compared to oxide ceramics, quartz has higher dimensional stability due to its lower coefficient of thermal expansion (CTE). However, quartz is silicon-based and therefore corrodes very rapidly, making its use very expensive. Aluminum nitride offers sufficient performance, but is extremely expensive, and there are relatively few suppliers capable of producing the large-diameter blanks required. [Overview of the project]

[0008] A gas distribution plate for a substrate processing system includes an outer ring having a stepped interface on its radially inner surface, and N inner rings, where N is an integer greater than zero. At least one of the N inner rings is divided circumferentially and includes an inner stepped interface and an outer stepped interface. The outer stepped interface of the radially outer inner ring of the N inner rings is configured to rest on and engage with the inner stepped interface of the outer ring. A central portion includes an outer stepped interface on its radially outer surface, and the outer stepped interface is configured to rest on and engage with the inner stepped interface of the radially inner inner ring of the N inner rings.

[0009] In other features, at least one of the N inner rings includes a plurality of gas through-holes. Each of the N inner rings includes C circumferential portions, where C is an integer greater than 1. Each of the C circumferential portions includes a body having a first arc-shaped portion and a second arc-shaped portion. The first arc-shaped portion is offset radially and circumferentially with respect to the second arc-shaped portion.

[0010] Other features include the first arc-shaped portion having an inner diameter and an outer diameter, and the second arc-shaped portion having an inner diameter and an outer diameter. The inner diameter of the first arc-shaped portion is larger than the inner diameter of the second arc-shaped portion and smaller than the outer diameter of the second arc-shaped portion. The outer ring, the N inner rings, and the central portion are made of RF-permeable material.

[0011] In other features, the outer ring, N inner rings, and central portion are made of alumina. In other features, the outer ring, N inner rings, and central portion are made of aluminum nitride. In other features, the outer ring is made of alumina, and the N inner rings and central portion are made of aluminum nitride.

[0012] Other features include polished outer rings, N inner rings, and interface surfaces of the central portion. In other features, the second arcuate portion of the first circumferential portion of the C circumferential portions lies below the first arcuate portion of the first circumferential portion of the C circumferential portions. The second arcuate portion of the first circumferential portion of the C circumferential portions includes a slot defining a plenum surrounding a gas through-hole. The slot is located on a cantilevered portion of the second arcuate portion that extends from the second arcuate portion of the first circumferential portion of the C circumferential portions.

[0013] In other features, the gas distribution plate further includes gas through-holes on the first arc-shaped portion of the second circumferential portion of the C circumferential portions, and when assembled, the gas through-holes on the first arc-shaped portion of the second circumferential portion of the C circumferential portions align with the gas through-holes on the second arc-shaped portion of the first circumferential portion of the C circumferential portions.

[0014] In other features, when nested together, the outer ring, the N inner rings, and the central portion define flat upper and lower surfaces.

[0015] The substrate processing system includes a processing chamber containing a substrate support. A coil is positioned outside the processing chamber. A gas distribution plate is positioned between the processing chamber and the coil.

[0016] In other features, at least one of the N inner rings includes a plurality of through holes. Each of the N inner rings includes C circumferential portions, where C is an integer greater than 1. Each of the C circumferential portions includes a body having a first arc-shaped portion and a second arc-shaped portion, the first arc-shaped portion being offset radially and circumferentially with respect to the second arc-shaped portion.

[0017] In other features, a gas distribution assembly is provided, which includes an upper plate and a gas distribution plate. The upper plate is disposed on the gas distribution plate. A gap for the passage of gas to one or more holes of the N inner rings exists between the upper plate and the gas distribution plate.

[0018] Further areas of applicability of the present disclosure will become apparent from the "Description of Embodiments", "Claims", and the drawings. The "Description of Embodiments" and specific examples are for illustrative purposes only and are not intended to limit the scope of the disclosure.

[0019] The present disclosure will be more fully understood from the detailed description and the accompanying drawings.

Brief Description of the Drawings

[0020] [Figure 1] FIG. 1 is a functional block diagram of an example of a substrate processing system including a gas distribution assembly according to the present disclosure.

[0021] [Figure 2] FIG. 2 is a perspective cross-sectional view of a radially and circumferentially divided gas distribution plate including a stepped outer ring and one or more divided stepped inner rings according to the present disclosure.

[0022] [Figure 3A] FIG. 3A is a perspective view of the upper surface of an outer ring according to the present disclosure. <Object: <Object: <Object:

[0023] <Object: <Object: [Figure 3B] FIG. 3B is a side cross-sectional view of an outer ring according to the present disclosure. <0000Y87> [Figure 4A] FIG. 4A is a perspective view of the upper surface of a first portion of a first divided stepped inner ring according to the present disclosure.

[0025] [Figure 4B]Figure 4B is a perspective view of the upper surface of the second portion of the first segmented stepped inner ring according to the present disclosure.

[0026] [Figure 4C] Figure 4C is a side cross-sectional view of the first portion of the first segmented stepped inner ring according to the present disclosure.

[0027] [Figure 5A] Figure 5A is a perspective view of the upper surface of the first portion of the second segmented stepped inner ring according to the present disclosure.

[0028] [Figure 5B] Figure 5B is a perspective view of the lower surface of the first portion of the second segmented stepped inner ring according to the present disclosure.

[0029] [Figure 5C] Figure 5C is a side cross-sectional view of the first portion of the second segmented stepped inner ring according to the present disclosure.

[0030] [Figure 6A] Figure 6A is a perspective view of the upper surface of the first portion of the third segmented stepped inner ring according to the present disclosure.

[0031] [Figure 6B] Figure 6B is a perspective view of the lower surface of the first portion of the third segmented stepped inner ring according to the present disclosure.

[0032] [Figure 7A] Figure 7A is a perspective view of the upper surface of the first portion of the fourth stepped inner ring according to the present disclosure.

[0033] [Figure 7B] Figure 7B is a perspective view of the lower surface of the first portion of the fourth stepped inner ring according to the present disclosure.

[0034] [Figure 8]Figure 8 shows a perspective cross-sectional view of another gas distribution assembly according to the present disclosure, including an upper plate and a divided gas distribution plate.

[0035] [Figure 9] Figure 9 shows a perspective cross-sectional view of the divided gas distribution plate shown in Figure 8.

[0036] [Figure 10] Figure 10 shows a cross-sectional view of the gas distribution assembly, illustrating the gas flow and the gap between the plate and the adjacent, interlocking ring segments. [Modes for carrying out the invention]

[0037] In drawings, reference numbers may be reused to identify similar and / or identical elements.

[0038] Currently, micro-electromechanical (MEM) devices are produced using high-etchation-rate processes involving high gas flow and high pressure, high RF power, and high process temperatures. To achieve acceptable uniformity while maintaining high etching rates, MEMS processes are highly sensitive to the location and uniformity of the gas distribution. Consequently, some MEM devices are produced using substrate processing systems in conjunction with TCP plasma.

[0039] The embodiments described herein include a gas distribution assembly comprising a top plate and a divided gas distribution plate. The top plate and gas distribution plate function as RF-permeable windows, allowing the generated RF signal to pass through the windows to the processing chamber. Each of the divided gas distribution plates according to this disclosure is a ring assembly comprising a plurality of rings, each ring may comprising one or more ring segments. Examples of various ring assemblies are shown in Figures 1 to 10. At least some of the rings may be divided radially and / or circumferentially. The ring segments interlock from the outside using continuously connected steps. In some embodiments, the ring segments have polished contact surfaces to reduce particle generation and to construct indirect paths to prevent uncertain gas flow. In some embodiments, the ring segments are made from alumina (Al2O3), but other materials, such as aluminum nitride (AlN), may be used. Divided gas distribution plates can be used at higher temperatures and higher power settings and can withstand higher pressures compared to undivided gas distribution plates made from similar materials. A gap exists between the ring segments to allow for expansion, reduce stress, and prevent damage to the ring segments.

[0040] Ring segments formed from AlN have improved thermal conductivity and thermal expansion coefficient compared to ring segments formed from Al2O3. As a result, a corresponding ring assembly including ring segments formed from AlN has a smaller temperature gradient, is subjected to less stress for a given operating temperature gradient, and therefore has a more durable structure. In some embodiments, one or more ring segments of a ring assembly are formed from Al2O3, and one or more other ring segments are formed from AlN. In one embodiment, one or more radially outermost ring segments are formed from Al2O3, and one or more radially innermost ring segments are formed from AlN.

[0041] Dividing the gas distribution plate radially and circumferentially creates expansion gaps between the continuously connected segments, as opposed to forming stress points where cracks may occur, thereby distributing and transferring thermal energy. The radial portions of the segments may include landings for through-holes to control the gas supply zone, while the outermost ring segment of the outermost ring may include grooves for O-ring sealing for vacuum integrity.

[0042] Referring now to Figure 1, an embodiment of the substrate processing system 110 according to the present disclosure is shown. The substrate processing system 110 includes a coil drive circuit 111. As shown, the coil drive circuit 111 includes an RF power supply 112 and a tuning circuit 113. The tuning circuit 113 may be directly connected to one or more inductive transformer-coupled plasma (TCP) coils 116. Alternatively, the tuning circuit 113 may be connected to one or more of the TCP coils 116 by an optional inverting circuit 115.

[0043] The tuning circuit 113 tunes the output of the RF power supply 112 to a desired frequency and / or phase, matches the impedance of the TCP coils 116, and divides the power among the TCP coils 116. The inverting circuit 115 is used to selectively switch the polarity of the current passing through one or more of the TCP coils 116. In some embodiments, the coil drive circuit 111 implements a transformer-coupled capacitive tuning (TCCT) matching network for driving the TCP coils 116. For example, a processing chamber using a TCCT matching network with switched capacitors is shown and described in U.S. Patent No. 9,515,633 by the same applicant, which is incorporated herein by reference in its entirety.

[0044] The upper part 124 of the processing chamber 128 includes a gas distribution assembly 121, which includes an upper plate 123 and a divided gas distribution plate 120 having gas through-holes (shown in Figure 2 below). The radially outermost portion of the gas distribution assembly 121 may be supported by a portion of the chamber wall or by a retainer 125, as shown. A gas plenum 127 is positioned above the divided gas distribution plate 120 on the upper plate 123. The upper plate 123 and the gas distribution plate 120 are positioned between the TCP coil 116 and the processing chamber 128. In some embodiments, process gas is supplied to the gas plenum 127 using gas nozzles, gas valves, distribution plates, conduits, etc. The processing chamber 128 further comprises a substrate support (or pedestal) 132. The substrate support 132 may include an electrostatic chuck (ESC), or a mechanical chuck or other type of chuck.

[0045] Process gas is supplied to the processing chamber 128 via the gas distribution assembly 121. The gas received in the plenum 127 is distributed to holes in the divided gas distribution plate 120. RF power is supplied to the TCP coil 116. Plasma 140 is generated and maintained inside the processing chamber 128. For example, a magnetic field generated by the TCP coil 116 travels through the upper plate 123 into the processing chamber 128. The magnetic field excites gas molecules in the processing chamber 128, generating plasma 140. The plasma 140 may be used to process (etch, deposit, clean, etc.) the exposed surface of the substrate 134. An RF power supply 150 and a bias matching circuit 152 may be used to bias the substrate support 132 during operation to control the ion energy. For example, the TCP coil 116 may include a radially arranged inner coil and a radially arranged outer coil surrounding the inner coil.

[0046] A gas supply system 156 may be used to supply a process gas mixture to the processing chamber 128. The gas supply system 156 may include a process and inert gas source 157 (e.g., including a deposition gas, etching gas, carrier gas, inert gas, etc.), a gas metering system 158 (e.g., a mass flow controller (MFC)) including valves and a mass flow controller, and a manifold 159. For example, the gas metering system 158 and the manifold 159 may be configured to supply an etching gas mixture to the processing chamber 128 during etching.

[0047] A heater / cooler 164 may be used to heat / cool the substrate support 132 to a predetermined temperature. The exhaust system 165 includes a valve 166 and a pump 167 for removing reactants from the processing chamber 128 by purging or exhaust.

[0048] The etching process may be controlled using a controller 154. The controller 154 monitors system parameters and controls the supply of the gas mixture, plasma generation, maintenance and extinction, and removal of reactants. In addition, the controller 154 may control various aspects such as the coil drive circuit 111, the RF power supply 150, and the bias matching circuit 152. In some embodiments, the substrate support 132 is temperature-adjustable. In one example, a temperature controller 168 may be connected to a plurality of heating elements 170, such as thermal control elements (TCEs), located within the substrate support 132. The temperature controller 168 may be used to control the plurality of heating elements 170 to control the temperature of the substrate support 132 and the substrate 134.

[0049] Referring here to Figure 2, the divided gas distribution plate 200 includes a plurality of nested ring segments, at least some of which are divided radially and / or circumferentially. The divided gas distribution plate 200 may replace the divided gas distribution plate 120 of Figure 1. The divided gas distribution plate 200 includes an outer ring 210. In some embodiments, the outer ring 210 includes annular slots 214 that extend partially or completely around the lower surface of the outer ring 210. One or more additional annular slots 214 may be located at spaced radial positions on the lower surface of the outer ring 210. The annular slots may be included and may function as thermal chokes to limit the transfer of thermal energy in adjacent areas. In some embodiments, the annular slots 214 are not included, as in the embodiments of Figures 8 to 10.

[0050] In some embodiments, one or more annular slots (or grooves) 215 may be located on the upper surface of the outer ring 210. The slots 215 may include an O-ring and provide a vacuum hermetically sealed environment between the divided gas distribution plate 200 and an upper plate such as the upper plate 123 in Figure 1.

[0051] A first stepped inner ring 220 is positioned radially inward of the outer ring 210 and engages with the outer ring 210. The first stepped inner ring 220 rests on a stepped interface 222 defined between it and the outer ring. In some embodiments, the first stepped inner ring 220 is divided into two or more circumferential parts, as shown in 226.

[0052] A second stepped inner ring 230 is positioned radially inward of the first stepped inner ring 220 and engages with the first stepped inner ring 220. The second stepped inner ring 230 rests on a stepped interface 232 between it and the first stepped inner ring. In some embodiments, the second stepped inner ring 230 is divided into two or more circumferential parts as shown in 236. The second stepped inner ring 230 may include one or more gas through-holes 238 extending from its upper surface to its lower surface.

[0053] The third stepped inner ring 240 is positioned radially inward of the second stepped inner ring 230 and engages with the second stepped inner ring 230. The third stepped inner ring 240 rests on a stepped interface 242 between it and the second stepped inner ring. In some embodiments, the third stepped inner ring 240 is divided into two or more circumferential parts as shown in 246.

[0054] The central portion 250 is positioned radially inward of the third stepped inner ring 240 and engages with the third stepped inner ring 240. The central portion 250 rests on a stepped interface 252 between it and the third stepped inner ring. The central portion 250 is not divided circumferentially. A single stepped outer ring, three stepped inner rings, and a central portion are shown, but additional or fewer stepped inner rings may be used. The second stepped inner ring 230 is shown to include a gas through-hole 238, while the second stepped inner ring 230 may include additional through-holes. In some embodiments, the first stepped inner ring, the third stepped inner ring, and / or the central portion may also include gas through-holes (not shown). In some embodiments, the upper and lower surfaces of the divided gas distribution plate 200 are generally flat (except for the annular slot 214).

[0055] The divided gas distribution plate 200 is shown to include three inner rings, but the gas distribution plate 200 may include one or more inner rings. The divided gas distribution plate 200 may be formed of Al2O3 and / or AlN. In one embodiment, the divided gas distribution plate 200 may be formed of Al2O3. In another embodiment, the divided gas distribution plate 200 may be formed of AlN. In yet another embodiment, the ring 210 is formed of Al2O3, and one or more of the inner rings (e.g., rings 220, 230, 240) and the central portion 250 are formed of AlN.

[0056] Referring here to Figures 3A and 3B, the outer ring 210 of Figure 2 is shown in more detail. The outer ring 210 includes an annular body 308 having a flat annular ring shape. The annular body 308 includes an upper surface 310 and a lower surface 314. The outer ring 210 further includes an annular slot 320 located on the upper surface 310. The radially inner surface of the outer ring 210 defines a stepped interface 330. In other words, the lower surface 314 extends radially inward relative to the upper surface 310 to form a step. In some embodiments, a first stepped inner ring 220 rests on the stepped interface 330.

[0057] Referring now to Figures 4A to 4C, the first stepped inner ring 220 of Figure 2 is shown in more detail. In Figure 4A, the first stepped inner ring 220 is divided in both the radial and circumferential directions. The first stepped inner ring 220 is shown to have two circumferential segments, but additional circumferential segments may be used.

[0058] The first stepped inner ring 220 includes a first circumferential portion 406, which includes a body 408 having an upper surface 410 and a lower surface 414. The body 408 includes a first arcuate portion 416 that rotates relative to a second arcuate portion 418. In other words, the first arcuate portion 416 and the second arcuate portion 418 have similar but offset arcuate lengths. In some embodiments, the first arcuate portion 416 and the second arcuate portion 418 have similar radial thicknesses. In some embodiments, the inner diameter of the first arcuate portion 416 is greater than the inner diameter of the second arcuate portion 418 and smaller than the outer diameter of the second arcuate portion 418. In some embodiments, the first arcuate portion 416 and the second arcuate portion 418 are made from a single monolithic material. In other embodiments, the first arc-shaped portion 416 and the second arc-shaped portion 418 are manufactured separately and then attached or joined together.

[0059] The end 422 of the first arc-shaped portion 416 extends circumferentially to the corresponding end 423 of the second arc-shaped portion 418. Similarly, the end 426 of the second arc-shaped portion 418 extends circumferentially to the corresponding end 427 of the first arc-shaped portion 416. In Figure 4B, the first stepped inner ring 220 includes a second circumferential portion 440 similar to the first circumferential portion 406. The first arc-shaped portion 416 and the second arc-shaped portion 418 define the inner and outer stepped interface 430.

[0060] Referring now to Figures 5A to 5C, the second stepped inner ring 230 of Figure 2 is shown in more detail. In Figure 5A, the second stepped inner ring 230 is divided in both the radial and circumferential directions. The second stepped inner ring 230 is shown to have two circumferential segments, but additional circumferential segments may be used.

[0061] The second stepped inner ring 230 includes a first circumferential portion 506 which includes a body 508 having an upper surface 510 and a lower surface 514. The body 508 defines a first arcuate portion 516 which rotates relative to the second arcuate portion 518. In other words, the first arcuate portion 516 and the second arcuate portion 518 have similar but offset arcuate lengths. In some embodiments, the first arcuate portion 516 and the second arcuate portion 518 have similar radial thicknesses. In some embodiments, the inner diameter of the first arcuate portion 516 is greater than the inner diameter of the second arcuate portion 518 and smaller than the outer diameter of the second arcuate portion 518.

[0062] The end 522 of the second arc-shaped portion 518 extends circumferentially to the corresponding end 523 of the first arc-shaped portion 516. Similarly, the end 526 of the first arc-shaped portion 516 extends circumferentially to the corresponding end 527 of the second arc-shaped portion 518. The first arc-shaped portion 516 and the second arc-shaped portion 518 define an inner and outer stepped interface 530.

[0063] The second stepped inner ring 230 includes a plurality of through holes 532. One or both of the ends 522 and 526 (the cantilevered portions thereof) may include slots 528 that define a plenum around one or more of the through holes 532. In Figure 5B, the second stepped inner ring 230 includes a second circumferential portion 540 (shown inverted) similar to the first circumferential portion 506.

[0064] Referring now to Figures 6A and 6B, the third stepped inner ring 240 of Figure 2 is shown in more detail. In Figure 6A, the third stepped inner ring 240 is divided in both the radial and circumferential directions. The third stepped inner ring 240 is shown to have two circumferential segments, but additional circumferential segments may be used.

[0065] The third stepped inner ring 240 includes a first circumferential portion 606 which includes a body 608 having an upper surface 610 and a lower surface 614. The body 608 defines the first arc-shaped portion 616 which rotates relative to the second arc-shaped portion 618.

[0066] The main body 608 defines a first arc-shaped portion 616 that rotates relative to the second arc-shaped portion 618. In other words, the first arc-shaped portion 616 and the second arc-shaped portion 618 have similar but offset arc lengths. In some embodiments, the first arc-shaped portion 616 and the second arc-shaped portion 618 have similar radial thicknesses. In some embodiments, the inner diameter of the first arc-shaped portion 616 is larger than the inner diameter of the second arc-shaped portion 618 and smaller than the outer diameter of the second arc-shaped portion 618.

[0067] The end 622 of the first arc-shaped portion 616 extends circumferentially to the corresponding end 623 of the second arc-shaped portion 618. The end 626 of the second arc-shaped portion 618 extends circumferentially to the corresponding end 627 of the first arc-shaped portion 616. In Figure 6B, the second stepped inner ring 230 includes a second circumferential portion 640 (shown inverted) similar to the first circumferential portion 606. The first arc-shaped portion 616 and the second arc-shaped portion 618 define the inner and outer stepped interface 630.

[0068] Referring now to Figures 7A and 7B, the central portion 250 of Figure 2 is shown in more detail. The central portion 250 includes a body 708 having an upper surface 710 and a lower surface 714. The upper part 722 of the body 708 has a cylindrical shape and a first diameter. The lower part 724 of the body 708 has a cylindrical shape and a second diameter smaller than the first diameter.

[0069] Figure 8 shows a gas distribution assembly 800, which includes an upper plate 802 and a divided gas distribution plate 804. The gas distribution assembly 800 may replace the gas distribution assembly 121 of Figure 1. The upper plate 802 includes a centrally located plenum 806 for receiving gas, which has a central hole 808. The gas received in the plenum 806 is guided through the central hole 808 and distributed between the upper plate 802 and the divided gas distribution plate 804 to one or more rings 810 of the divided gas distribution plate 804.

[0070] The ring 810 may include a support ring 820, one or more inner (or intermediate) rings (for example, three intermediate rings 822, 824, and 826 are shown), and a central portion (or stepped circular plug) 828. Stepped interfaces 830, 832, and 834 are located between the rings 820, 822, 824, and 826. A stepped interface 836 is located between the ring 826 and the central portion 828. Ring 820 supports ring 822, and then ring 822 supports ring 824. Ring 824 supports ring 826, and then ring 826 supports the central portion 828. Each of the intermediate rings may be divided and may include ring segments. Exemplary ring segments 840, 842, 844, 846, 848, 850, 852, and 854 for rings 822, 824, and 826 are shown. In Figure 8, ring segments 840, 842, 844, 846, 848, 850, 852, and 854 are shown as being visible through the upper plate 802, but in reality, they are not visible through the upper plate 802.

[0071] The ring 820 does not include an annular slot (e.g., slot 214 in Figure 2), but includes an annular groove 860 in which an O-ring (not shown) can be placed, providing an annular vacuum seal between the upper plate 802 and the divided gas distribution plate 804.

[0072] The upper plate 802 and the divided gas distribution plate 804 may be formed of Al2O3 and / or (AlN). In one embodiment, the upper plate 802 and the divided gas distribution plate 804 are formed of Al2O3. In another embodiment, the upper plate 802 and the divided gas distribution plate 804 are formed of AlN. In yet another embodiment, the upper plate 802 and the ring 820 are formed of Al2O3, and one or more intermediate rings (e.g., rings 822, 824, 826) and the central portion 828 are formed of AlN.

[0073] The gas distribution assembly 800 will be described further with reference to Figures 9 and 10. Figure 9 shows a divided gas distribution plate 804. The divided gas distribution plate 804 includes rings 820, 822, 824, 826 and a central portion 828. Ring 820 includes an annular groove 860. Rings 820, 822, 824, and 826 include ring segments, for example, ring segments 840, 842, 844, 846, 848, 850, 852, and 854. Circular interfaces 900, 902, and 904 are shown between rings 820, 822, 824, and 826. Circular interface 906 is shown between ring 826 and the central portion 828. Radially extending interfaces 910, 912, 914, 916, 918, 920, and 922 are shown between the ring segments of rings 822, 824, and 826.

[0074] The ring segments 848, 850 and other ring segments of the intermediate ring 824 may include gas holes 920, some of which are shown. Although the ring segments of the intermediate ring 824 are shown having gas holes, the ring segments of rings 822 and 826 may also include gas holes. The gas is received through the holes and passes into the corresponding processing chamber.

[0075] Figure 10 shows a gas distribution assembly 800, illustrating the gas flow and the gap between plates 802, 804 and the ring segments that mesh with each other. The upper plate 802 includes a plenum 806 and a central hole 808. The divided gas distribution plate 804 includes rings 820, 822, 824, 826 and a central portion 828, which include annular interfaces 830, 832, 834, 836.

[0076] (i) A small gap G1 exists between the upper plate 802 and (ii) the rings 824, 826 and the central portion 828. The gap G1 may be provided through a circular recess in the upper plate 802. In addition or alternatively, to provide the gap G1, the rings 824, 826 and the central portion 828 may be shorter than the rings 820, 822. The region between plates 802, 804 and associated with the gap G1 may extend laterally radially inward and upward to the hole 1000, across the central portion 828, the ring 826, and a portion of the ring 824.

[0077] In the example shown, the gas is received in the plenum 806, passes vertically through hole 808, radially disperses through gap G1 to a hole in ring 824 (e.g., hole 1000, or hole 920 in Figure 9), passes vertically through the hole and enters the processing chamber. This is indicated by arrow 1002. In one embodiment, gap G1 is between 0.011 inches (i.e., about 0.28 millimeters) and 0.023 inches (i.e., about 0.58 millimeters). In another embodiment, gap G1 is equal to or about 0.017 inches (i.e., about 0.43 millimeters). In the example shown, there is no gap between ring 822 and upper plate 802, but a gap may exist if ring 822 contains gas holes.

[0078] The annular interfaces 830, 832, 834, and 836 each include upper vertical sections 1010, 1012, 1014, and 1016, central horizontal sections 1020, 1022, 1024, and 1026, and lower vertical sections 1030, 1032, 1034, and 1036, respectively. The upper vertical sections 1010, 1012, 1014, and 1016 may have a gap of the same size, referred to as G2 in Figure 10. The lower vertical sections 1030, 1032, 1034, and 1036 may have a gap of the same size, referred to as G3 in Figure 10. Although G2 and G3 are shown only for interface 824, the gaps in the vertical sections of interfaces 830, 832, and 836 may also be referred to as G2 and G3. In one embodiment, gaps G2 and G3 are between 0.010 inches (i.e., about 0.25 millimeters) and 0.025 inches (i.e., about 0.61 millimeters), respectively. In another embodiment, gaps G2 and G3 are equal to or about 0.013 inches (i.e., about 0.33 millimeters). Gaps G2 and G3 of the vertical sections 1010, 1012, 1014, 1016, 1030, 1032, 1034, and 1036 are provided to accommodate the expansion of rings 820, 822, 824, 826, and the central section 828. Each of the central horizontal sections 1020, 1022, 1024, and 1026 has no gap, as the corresponding central section or inner ring rests on the corresponding outer ring.

[0079] In one embodiment, the joint surfaces of rings 820, 822, 824, 826 and central portion 828, associated with annular interfaces 830, 832, 834, 836, are polished to provide a gas seal. The gas seal is provided to prevent gas from passing between rings 820, 822, 824, 826 and / or between ring 826 and central portion 828.

[0080] The segmented gas distribution plate is resistant to failure caused by extreme thermal input without resorting to compromises with materials such as quartz or expensive materials such as nitride ceramics. The segmented gas distribution plate is a passive, maintenance-free device and can be manufactured using conventional methods. Using segmented gas distribution plates made of aluminum oxide reduces initial costs and extends the lifespan of the gas distribution plate under harsh processing conditions. Segmented gas distribution plates made of aluminum nitride offer improved durability.

[0081] The foregoing description is essentially illustrative and is not intended to limit the Disclosure, its application, or its use. The broad teachings of the Disclosure can be realized in various ways. Therefore, although the Disclosure includes certain examples, the true scope of the Disclosure should not be limited in this way, as other modifications will become apparent when examining the drawings, specification, and the claims below. It should be understood that one or more steps in the Method may be performed in different orders (or simultaneously) without altering the principles of the Disclosure. Furthermore, although each embodiment is described above as having certain features, one or more of these features described in relation to any embodiment of the Disclosure may be implemented in any of the other embodiments and / or combined with any of the features of the other embodiments, even if such combinations are not explicitly described. In other words, the embodiments described are not mutually exclusive, and rearranging the order of one or more embodiments remains within the scope of the Disclosure.

[0082] Spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers) are described using a variety of terms, including “connected,” “engaged,” “joined,” “adjacent,” “next to,” “above,” “upper,” “below,” and “positioned.” Unless explicitly stated to be “direct,” where the above disclosure describes a relationship between a first element and a second element, that relationship may be a direct relationship in which there are no other intervening elements between the first and second elements, or it may be an indirect relationship in which one or more intervening elements exist between the first and second elements (either spatially or functionally). As used herein, the phrases “at least one of A, B, and C,” and “at least one of A, B, or C,” should be interpreted as meaning a logic using non-exclusive OR (A OR B OR C), and not as “at least one of A, at least one of B, and at least one of C.”

[0083] In some implementations, the controller is part of a system which may be part of the embodiments described above. Such a system may comprise a semiconductor processing apparatus including processing tools(s), chambers(s), processing platforms(s), and / or specific processing components (such as wafer pedestals, gas flow systems). These systems may be incorporated into electronics for controlling pre-processing, in-processing, and post-processing operations on semiconductor wafers or substrates. The electronics may be referred to as “controllers” which control various components or sub-components of the system(s). Depending on the processing requirements and / or the type of system, the controller may be programmed to control any of the processes disclosed herein, including, but are not limited to, the delivery of processing 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 rate settings, fluid delivery settings, position and work settings, loading and unloading of wafers into and out of tools and other transport tools connected to or interfaced with a particular system and / or load lock.

[0084] Broadly speaking, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software, which receives and issues instructions, controls operations, enables cleaning operations, and enables endpoint measurements. The integrated circuit may include a chip in the form of firmware that stores program instructions, a chip defined as a digital signal processor (DSP), an application-specific integrated circuit (ASIC), and / or one or more microprocessors, or a microcontroller that executes program instructions (e.g., software). Program instructions are instructions communicated to the controller in the form of various individual settings (or program files) that define work parameters for performing a particular process on or against a semiconductor wafer, or against a system. In some embodiments, the work parameters may be part of a recipe defined by a process engineer to implement one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0085] In some implementations, the controller may be part of a computer that is integrated into, coupled to, or networked to the system, or a combination thereof. For example, the controller may be in the “cloud” or all or part of a fab host computer system, thereby enabling remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of fabrication work, investigate the history of past fabrication work, investigate trends or performance indicators from multiple fabrication work, modify parameters of the current process, set up subsequent processing steps for the current process, or start a new process. In some embodiments, a remote computer (e.g., a server) may provide process recipes to the system via a network that may include a local network or the internet. The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then communicated from the remote computer to the system. In some embodiments, the controller receives instructions in data format that specify parameters for each processing step performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool that the controller is configured to interface with or control. Therefore, as described above, the controller may be distributed by comprising one or more individual controllers, which are networked together and operate toward common purposes such as processes and control as described herein. An example of a distributed controller for such purposes may be one or more integrated circuits on a chamber that are in communication with one or more integrated circuits located remotely (e.g., at the platform level or as part of a remote computer), which together control processes in the chamber.

[0086] Exemplary systems may include, but are not limited to, plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etching 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 etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing systems that are related to or may be used in the fabrication and / or manufacture of semiconductor wafers.

[0087] As described above, depending on the process steps performed by the tool, the controller may communicate with one or more of the following: other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, the main computer, another controller, or tools used for material handling to load and unload wafer containers between tool locations and / or load ports within the semiconductor manufacturing plant. The present invention can also be realized in the following embodiments, for example. Application Example 1: A gas distribution plate for a substrate processing system, An outer ring with a stepped interface on its radially inner surface, N inner rings, N is an integer greater than zero, At least one of the N inner rings is divided in the circumferential direction and includes an inner stepped interface and an outer stepped interface, The outer stepped interface of the radially outer inner ring among the N inner rings is configured to be placed on the inner stepped interface of the outer ring and to engage with the inner stepped interface, A gas distribution plate comprising: a central portion, the central portion including an outer stepped interface on the radially outer surface of the central portion, the outer stepped interface being mounted on the inner stepped interface of an inner ring that is radially inward of the N inner rings and configured to engage with the inner stepped interface. Application example 2: A gas distribution plate according to Application Example 1, wherein at least one of the N inner rings includes a plurality of gas through holes. Application Example 3: A gas distribution plate as described in Application Example 2, wherein the outer ring, the N inner rings, and the central portion define a flat upper surface and a flat lower surface when nested together. Application Example 4: A gas distribution plate as described in Application Example 1, wherein N=2. Application Example 5: A gas distribution plate as described in Application Example 1, wherein N=3. Application example 6: A gas distribution plate as described in Application Example 1, The aforementioned N inner rings contain C circumferential portions, where C is an integer greater than 1. Each of the C circumferential portions includes a body having a first arc-shaped portion and a second arc-shaped portion. A gas distribution plate wherein the first arc-shaped portion is offset radially and circumferentially from the second arc-shaped portion. Application example 7: A gas distribution plate as described in Application Example 6, wherein C=2. Application Example 8: A gas distribution plate as described in Application Example 6, The first arc-shaped portion has an inner diameter and an outer diameter, The second arc-shaped portion has an inner diameter and an outer diameter, A gas distribution plate wherein the inner diameter of the first arc-shaped portion is larger than the inner diameter of the second arc-shaped portion and smaller than the outer diameter of the second arc-shaped portion. Application example 9: A gas distribution plate as described in Application Example 6, The second arc-shaped portion of the first circumferential portion among the C circumferential portions is located below the first arc-shaped portion of the first circumferential portion among the C circumferential portions, The second arc-shaped portion of the first circumferential portion among the C circumferential portions includes a slot that defines a plenum surrounding a gas penetration hole. The slot is located on a gas distribution plate, which extends from the second arc-shaped portion of the first circumferential portion among the C circumferential portions, and is situated on a cantilever portion of the second arc-shaped portion. Application Example 10: A gas distribution plate according to Application Example 9, further comprising a gas through-hole on the first arc-shaped portion of the second circumferential portion among the C circumferential portions, A gas distribution plate in which, when assembled, the gas through-holes in the first arc-shaped portion of the second circumferential portion of the C circumferential portions are aligned with the gas through-holes in the second arc-shaped portion of the first circumferential portion of the C circumferential portions. Application Example 11: A gas distribution plate according to Application Example 1, wherein the outer ring, the N inner rings, and the central portion are made of an RF-permeable material. Application Example 12: A gas distribution plate as described in Application Example 1, wherein the outer ring, the N inner rings, and the central portion are made of alumina. Application Example 13: A gas distribution plate as described in Application Example 1, wherein the outer ring, the N inner rings, and the central portion are made of aluminum nitride. Application Example 14: A gas distribution plate as described in Application Example 1, The outer ring is made of alumina, A gas distribution plate in which the N inner rings and the central portion are made of aluminum nitride. Application Example 15: A gas distribution plate according to Application Example 1, wherein the outer ring, the N inner rings, and the interface surface of the central portion are polished. Application Example 16: A gas distribution assembly, The top plate and The gas distribution plate described in Application Example 1 is provided, The upper plate is placed on the gas distribution plate. A gas distribution assembly in which a gap exists between the upper plate and the gas distribution plate for the passage of gas to one or more holes among the N inner rings. Application Example 17: A substrate processing system, A processing chamber including a substrate support, A coil positioned outside the processing chamber, A substrate processing system comprising a gas distribution plate as described in Application Example 1, disposed between the processing chamber and the coil. Application Example 18: A substrate processing system according to Application Example 17, wherein at least one of the N inner rings includes a plurality of through holes. Application Example 19: A substrate processing system as described in Application Example 17, wherein N=2. Application Example 20: The substrate processing system described in Application Example 17, The aforementioned N inner rings contain C circumferential portions, where C is an integer greater than 1. Each of the C circumferential portions includes a body having a first arc-shaped portion and a second arc-shaped portion. A substrate processing system in which the first arc-shaped portion is offset radially and circumferentially from the second arc-shaped portion. Application Example 21: A substrate processing system as described in Application Example 20, wherein C=2.

Claims

1. A gas distribution assembly for a substrate processing system, An upper plate comprising a first plenum located in the center of the upper plate and having at least one gas hole, the first plenum being configured to receive gas for passage through at least one gas hole, A gas distribution plate, An outer ring comprising an outer ring having a stepped interface on its radially inner surface, A segment having a radially outer surface, A gas distribution plate comprising, The radially outer surface of at least one segment is configured to rest on the stepped interface of the outer ring and to engage with the stepped interface. The upper plate is placed on the gas distribution plate, A gas distribution assembly wherein a gap for gas distribution exists between the upper plate and the gas distribution plate, between the at least one gas hole in the upper plate and the plurality of gas through-holes in one or more of the at least one segment.

2. The gas distribution assembly according to Claim 1, A gas distribution assembly in which at least one of the segments is circular.

3. The gas distribution assembly according to claim 1, further, A gas distribution assembly comprising at least one inner ring circumferentially divided into a plurality of segments, including the aforementioned at least one segment.

4. A gas distribution assembly according to claim 1, The at least one segment is provided with an outer stepped interface on the radially outer surface of the at least one segment. A gas distribution assembly wherein the outer stepped interface of at least one segment is configured to rest on the stepped interface of the outer ring and to engage with the stepped interface.

5. A gas distribution assembly according to Claim 1, The aforementioned at least one segment is a gas distribution assembly comprising only one segment.

6. A gas distribution assembly according to claim 1, The aforementioned at least one segment is a gas distribution assembly comprising multiple segments.

7. A gas distribution assembly according to claim 1, The at least one segment comprises N inner ring segments, where N is an integer of 1 or more, A gas distribution assembly in which the radially outermost inner ring segment of the N inner ring segments is placed on the stepped interface of the outer ring.

8. A gas distribution assembly according to claim 7, The at least one segment comprises a central segment, A gas distribution assembly in which the central segment is mounted on the radially innermost inner ring segment of the N inner ring segments and configured to engage with the innermost inner ring segment.

9. A gas distribution assembly according to claim 8, At least one of the N inner ring segments includes a plurality of gas through holes, A gas distribution assembly in which the plurality of gas through-holes in one or more of the at least one segment includes the plurality of gas through-holes in at least one of the N inner ring segments.

10. A gas distribution assembly according to claim 8, A gas distribution assembly in which the outer ring, the N inner ring segments, and the central segment define a flat upper surface and a flat lower surface when nested together.

11. A gas distribution assembly according to claim 8, A gas distribution assembly where N is 2 or greater.

12. A gas distribution assembly according to claim 8, Each of the N inner ring segments contains C circumferential portions, where C is an integer greater than 1. Each of the C circumferential portions includes a body having a first arc-shaped portion and a second arc-shaped portion. A gas distribution assembly in which the first arc-shaped portion of each of the C circumferential portions of the main body is offset radially and circumferentially with respect to the second arc-shaped portion of the main body.

13. A gas distribution assembly according to claim 12, Each of the first arc-shaped portion of the main body of the C circumferential portions has an inner diameter and an outer diameter. Each of the C circumferential portions of the main body has an inner diameter and an outer diameter. A gas distribution assembly in which the inner diameter of each of the first arc-shaped portions is larger than the inner diameter of each of the second arc-shaped portions and smaller than the outer diameter of each of the second arc-shaped portions.

14. A gas distribution assembly according to claim 12, The second arc-shaped portion of the first circumferential portion among the C circumferential portions is located below the first arc-shaped portion of the first circumferential portion among the C circumferential portions, The second arc-shaped portion of the first circumferential portion among the C circumferential portions includes a slot that defines a second plenum surrounding a gas penetration hole in the second arc-shaped portion. The plurality of gas through-holes in one or more of the at least one segment include the gas through-holes in the second arc-shaped portion, The slot is located on a cantilever portion of the second arc-shaped portion, which extends from the second arc-shaped portion of the first circumferential portion among the C circumferential portions, in a gas distribution assembly.

15. A gas distribution assembly according to claim 14, further, A gas penetration hole is provided in the first arc-shaped portion of the second circumferential portion among the C circumferential portions. The plurality of gas through-holes in one or more of the at least one segment include the gas through-holes in the first arc-shaped portion, A gas distribution assembly in which, when assembled, the gas through-holes in the first arc-shaped portion of the second circumferential portion of the C circumferential portions are aligned with the gas through-holes in the second arc-shaped portion of the first circumferential portion of the C circumferential portions.

16. A gas distribution assembly according to claim 8, A gas distribution assembly in which the outer ring, the N inner ring segments, and the central segment are made of an RF-permeable material.

17. A gas distribution assembly according to claim 8, A gas distribution assembly in which the outer ring, the N inner ring segments, and the central segment are made of alumina or aluminum nitride.

18. A gas distribution assembly according to claim 8, The outer ring is made of alumina, A gas distribution assembly in which the N inner ring segments and the central segment are made of aluminum nitride.

19. A gas distribution assembly according to claim 8, A gas distribution assembly in which the interface surfaces of the outer ring, the N inner ring segments, and the central segment are polished.

20. A gas distribution assembly according to claim 1, A gas distribution assembly comprising a central segment having the radially outer surface, wherein at least one of the segments is a central segment having the radially outer surface.

21. A gas distribution assembly according to claim 20, The central segment and the outer ring share the same central axis in this gas distribution assembly.

22. A gas distribution assembly according to claim 20, The central segment is the gas distribution assembly, which is the central part of the gas distribution plate.

23. A gas distribution assembly according to claim 1, A gas distribution assembly in which the upper plate and the gas distribution plate are dielectric windows.

24. A substrate processing system, A processing chamber including a substrate support, A coil positioned outside the processing chamber, A substrate processing system comprising a gas distribution assembly according to claim 1, disposed between the processing chamber and the coil.

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