Showerhead design for plasma-enhanced deposition

Abstract

A spray head assembly for a semiconductor manufacturing processing chamber and a semiconductor manufacturing processing chamber using the spray head assembly are described. The spray head assembly includes a backplate and a frontplate with an embedded heater. The radius of the embedded heater is sufficient to position the heater above the sidewall of the processing chamber and reduce temperature non-uniformity of the wafer during processing.

Description

Technical Field

[0001] Embodiments of the present disclosure are directed to showerheads for semiconductor manufacturing process chambers. In particular, embodiments of the present disclosure are directed to showerhead designs for plasma enhanced deposition of molybdenum films. Prior Art

[0002] Reliable production of sub-micron and smaller features is one of the key requirements for very large scale integrated circuit (VLSI) and ultra large scale integrated circuit (ULSI) semiconductor components. However, as circuit technology continues to miniaturize, the size and pitch of circuit features (such as interconnects) place additional demands on processing capabilities. Various semiconductor components (such as interconnects, vias, capacitors, transistors) require precise placement of high aspect ratio features. Reliable molding of these components is critical to further increase component and density.

[0003] In addition, the electronic components and semiconductor industries continue to strive to improve yields while increasing the uniformity of layers deposited on increasingly larger surface areas of substrates. These factors, combined with new materials, also enable higher integration densities of integrated circuits per unit area on substrates.

[0004] As component sizes continue to shrink, the gaps / spaces between components are also shrinking, increasing the difficulty of physically isolating components. Filling the high aspect ratio trenches / spaces / gaps between components, which are often irregular in shape, with high-quality dielectric materials is an increasing challenge for existing methods, including gap filling, hard masking, and spacer application.

[0005] Molybdenum and molybdenum-based films have attractive material and conductive properties. These films have been proposed and tested for applications in semiconductor and microelectronic front-end to back-end components. Plasma enhanced atomic layer deposition (PEALD) of molybdenum requires high uniformity, moderate to high temperatures to achieve seamless uniform gap fill and sufficient throughput. These requirements are difficult to achieve with existing process chamber hardware and showerhead designs.

[0006] Therefore, there is a need in the art for improved showerheads and processing chambers for plasma enhanced film deposition. Summary of the invention

[0007] One or more specific embodiments of the present disclosure relate to a showerhead assembly for a semiconductor manufacturing process chamber. The showerhead assembly includes a backing plate, a heater, and a face plate. The backing plate has a front surface and a rear surface defining a thickness of the backing plate. An inlet opening is located at the center of the backing plate and extends through its thickness. The backing plate has an outer portion and an inner portion, and the front surface of the inner portion is concave. The heater is embedded in the thickness of the backing plate. The heater is circular, and its radius is measured from the central axis of the backing plate. The radius of the heater is greater than the radius of the inner portion of the backing plate, so that the heater is located in the outer portion of the backing plate. The face plate has a front surface and a rear surface defining a thickness of the face plate. The face plate has an inner portion and an outer portion. A plurality of apertures extend through the thickness of the face plate in the inner portion. A plurality of angled openings extend through the thickness of the outer portion of the face plate. The center of the front surface opening of the plurality of angled openings has a radius from the central axis of the face plate that is greater than the center radius of the rear surface opening.

[0008] Additional specific embodiments of the present disclosure are directed to a semiconductor manufacturing process chamber including a showerhead assembly as described herein. An inlet flange is connected to a rear surface of a backing plate. The inlet flange has an inner channel aligned with a central opening of the backing plate. The inner channel has an upper portion and a lower portion. The inner diameter of the upper portion is greater than the inner diameter of the lower portion. The process chamber includes a chamber sidewall and a chamber bottom. The showerhead assembly is positioned such that a bottom surface of a pumping ring contacts a top surface of the chamber sidewall to form an interior of the process chamber. A substrate support is located within the interior of the process chamber. The substrate support has a support surface configured to support a wafer during processing. The support surface is spaced from a front surface of the faceplate to form a process gap.

[0009] Further specific embodiments of the present disclosure relate to a showerhead assembly for a semiconductor manufacturing process chamber. The showerhead assembly includes a backing plate, a face plate, and a pumping ring. The backing plate has a heater embedded within its thickness. An inlet opening in the center of the backing plate extends through the thickness of the backing plate. An inner portion of the front surface of the backing plate is concave. The radius of the heater is greater than the radius of the inner portion of the front surface. The inner portion of the face plate has a plurality of apertures extending through the thickness of the face plate. The outer portion of the face plate has a plurality of angled openings extending through the thickness of the face plate. The pumping ring is connected to the backing plate via a plurality of fasteners extending through the face plate. Simple diagram description

[0010] In order to be able to understand the above-mentioned features of the present disclosure in detail, the present disclosure may be described in more detail with reference to specific embodiments, which are briefly summarized above, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings illustrate only specific embodiments of the present disclosure and are therefore not to be considered as limiting the scope thereof, as the present disclosure may admit of other equally effective embodiments.

[0011] Figure 1 shows a cross-sectional schematic diagram of a processing chamber according to one or more specific embodiments of the present disclosure;

[0012] Figure 2 is an expanded view of the processing chamber back plate shown in Figure 1;

[0013] Figure 3 is a sectional view of region III in Figure 2;

[0014] Figure 4 is a cross-sectional view of a portion of the processing chamber of Figure 1;

[0015] Figure 5 is a regional view of the processing chamber panel of Figure 1;

[0016] Figure 6 shows an expanded view of region VI in Figure 1;

[0017] FIG. 7 is a schematic diagram showing a multi-station processing chamber consisting of more than one semiconductor manufacturing processing chamber according to one or more specific embodiments of the present disclosure; and

[0018] Figure 8A shows an isometric view of a pumping ring according to one or more specific embodiments of the present disclosure;

[0019] Figure 8B shows a top plan view of the pumping ring of Figure 8A;

[0020] FIG. 9A shows a top plan view of a choke plate according to one or more specific embodiments of the present disclosure; and

[0021] 9B shows a bottom plan view of a choke plate according to one or more embodiments of the present disclosure. Implementation

[0022] Before describing several specific embodiments of the present disclosure, it should be understood that the present disclosure is not limited to the structural details or process steps set forth in the following description. The present disclosure is capable of other specific embodiments and can be implemented or carried out in various ways.

[0023] In this specification and the appended claims, the term "substrate" refers to a surface or a portion of a surface on which a process acts. It will also be understood by those skilled in the art that reference to a substrate may also refer to only a portion of a substrate unless the context clearly indicates otherwise. In addition, reference to deposition on a substrate may refer to either a bare substrate or a substrate on which one or more films or features are deposited or formed.

[0024] As used herein, "substrate" refers to any substrate or material surface formed on a substrate on which film processing is performed during the manufacturing process. For example, substrate surfaces on which processing may be performed include materials such as silicon, silicon oxide, strained silicon, silicon on insulator (SOI), carbon-doped silicon oxide, amorphous silicon, doped silicon, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive materials, depending on the application. Substrates include, but are not limited to, semiconductor wafers. The substrate may be exposed to a pretreatment process to polish, etch, reduce, oxidize, hydroxylate, anneal, UV cure, e-beam cure, and / or bake the substrate surface. In addition to performing film processing directly on the surface of the substrate itself, in the present disclosure, any of the disclosed film processing steps may also be performed on underlying layers formed on the substrate, as disclosed in detail below, and the term "substrate surface" is intended to include such underlying layers as indicated by the context. Thus, for example, where a film / layer or portion of a film / layer has been deposited onto a substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0025] As used herein, "atomic layer deposition" or "cyclic deposition" refers to a process that includes sequential exposure of two or more reactive compounds to deposit a layer of material on a substrate surface. As used herein, "atomic layer deposition" or "cyclic deposition" refers to a process that includes sequential exposure of two or more reactive compounds to deposit a layer of material on a substrate surface. The substrate or a portion of the substrate is separately exposed to two or more reactive compounds, which are introduced into a reaction zone of a processing chamber. In a time-domain ALD process, there is a time delay interval between exposure to each reactive compound to allow each compound to attach and / or react on the substrate surface and then be cleared from the processing chamber. The reactive compounds can be said to be exposed to the substrate sequentially. In a spatial ALD process, different portions of the substrate surface or materials on the substrate surface are simultaneously exposed to two or more reactive compounds, so that any given point on the substrate is not substantially exposed to more than one reactive compound at the same time. As used in this specification and the appended claims, the term "substantially" as used in this context means that one skilled in the art will understand that, due to diffusion, a small portion of the substrate may be exposed to multiple reactive gases simultaneously and that such simultaneous exposure is unintentional.

[0026] In one aspect of a time-domain ALD process, a first reactive gas (i.e., a first precursor or compound A) is pulsed into a reaction zone followed by a first time delay. Next, a second precursor or compound B is pulsed into the reaction zone followed by a second delay. During each time delay, a purge gas (e.g., argon) is introduced into the processing chamber to purge the reaction zone or otherwise remove any residual reactive compounds or reaction byproducts in the reaction zone. Alternatively, the purge gas may continue to flow throughout the deposition process such that only the purge gas flows during the time delays between pulsing of the reactive compounds. Another scenario is to pulse the reactive compounds until a desired film or film thickness is formed on the substrate surface. In either scenario, the ALD process of pulsing compound A, purge gas, compound B, and purge gas is a cycle. A cycle may start with either compound A or compound B and continue the respective cycle sequence until a film having a predetermined thickness is achieved.

[0027] In one embodiment of the spatial ALD process, a first reactive gas and a second reactive gas (e.g., nitrogen) are delivered to the reaction zone simultaneously but separated by an inert gas curtain and / or a vacuum curtain. The substrate moves relative to the gas delivery device so that any given point on the substrate is exposed to the first reactive gas and the second reactive gas. The gas curtain can be any suitable gas separation arrangement known to a skilled artisan. For example, in some embodiments of the spatial ALD processing chamber, the gas curtain is formed by a combination of a purge gas port and a vacuum port to maintain separation between the reactive gases and prevent gas phase reactions. In some embodiments of the spatial ALD processing chamber, the independent processing stations are configured to form a small processing environment in each station.

[0028] In this specification and the appended claims, the terms "reactive compound", "reactive gas", "reactive substance", "precursor", "processing gas", etc. are used interchangeably to refer to a material having a substance capable of undergoing a surface reaction (e.g., chemical adsorption, oxidation, reduction, cycloaddition) with a substrate surface or a substance on the substrate surface. The substrate or a portion of the substrate is sequentially exposed to two or more reactive compounds, which are introduced into a reaction zone of a processing chamber.

[0029] Specific embodiments of the present disclosure provide a processing chamber and a showerhead for a processing chamber that can utilize existing station structures to achieve plasma enhanced gap filling of molybdenum with minimal design changes and reduced costs.

[0030] Some specific embodiments of showerhead designs enable novel precursor delivery for conductively coupled plasma (CCP) molybdenum processes. Improvements over prior designs include, but are not limited to, incorporation of asymmetric showerhead contacts, thinner gas box designs, and simplified embedded tubular heaters for thermal uniformity and design / cost simplification. The terms "gas box" and "backing plate" are used interchangeably herein, as will be appreciated by those skilled in the art. A coated gas box plenum (also referred to as a showerhead plenum or showerhead assembly plenum) is used for chemical compatibility and to reduce the cost of the chamber lid.

[0031] Embodiments of the present disclosure include embedded tubular heaters, whereas previous mechanically processed components contacted the tubular heaters with the graphite sheet. Some embodiments incorporate thinner gas boxes (backing plates) by reducing the need for cooling channels. Some embodiments adjust the gas flow by the length of the gas manifold.

[0032] Some embodiments include setting an asymmetric minimum contact between the pumping ring and the showerhead faceplate to form a separation from the chamber body to act as a heat sink.

[0033] Some embodiments include coated airbox plenums and / or coated panels for chemical compatibility. Some embodiments provide higher emissivity to aid in heating the airbox and / or panels. In some embodiments, the airbox plenum has a coating with an emissivity in the range of 0.8-0.9.

[0034] Some embodiments provide chlorine compatibility and moisture permeation improvements. Some embodiments prevent backflow from a remote plasma source (RPS) through continuous inert gas purge, thereby eliminating the need for isolation valves for each station in a multi-station processing chamber.

[0035] In an exemplary four-station chamber, the edge temperature uniformity is lower than the center temperature uniformity due to the showerhead conducting heat to the chamber through the pump pad. To mitigate the thermal non-uniformity, a minimum contact is used on the pump pad to minimize the conduction heat from the showerhead to the pump pad. In some specific embodiments, the minimum contact is greater than 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, or 0.3 mm in the edge contact area.

[0036] In some embodiments, the heating coil position of the process chamber is moved to the gas box (back plate). The panel edge temperature and the wafer edge temperature are generally lower than the center temperature due to heat loss at the edge. For example, heat loss occurs due to contact with the chamber wall as a heat sink. To mitigate thermal non-uniformity, in some embodiments, a coil heater with a radius of about 150 mm is applied at the gas box (back plate).

[0037] 1, one or more embodiments of the present disclosure are directed to a semiconductor manufacturing process chamber 100 including a showerhead assembly 110. The showerhead assembly 110 includes a backing plate 120 and a face plate 130. In some embodiments, the showerhead assembly 110 further includes a pumping ring 140. The showerhead assembly 110 shown in FIG. 1 includes a backing plate 120, a face plate 130, and a pumping ring 140. However, a skilled artisan will recognize that the pumping ring 140 may be separate from the showerhead assembly 110, or in some embodiments, may be omitted from the semiconductor manufacturing process chamber 100.

[0038] The semiconductor manufacturing process chamber 100 includes a chamber body 101 having sidewalls 102 and a bottom wall 103. The chamber body 101, together with the showerhead assembly 110, encloses an interior 105 of the semiconductor manufacturing process chamber 100. The sidewalls 102 and the bottom wall 103 may be integrally formed or may be separate components connected together by any suitable connectors or fasteners known to those skilled in the art. During processing, the interior 105 of the semiconductor manufacturing process chamber 100 is typically maintained at a controlled pressure (typically a low pressure environment) using one or more gas inlets (not shown) and one or more exhaust ports (not shown). Those skilled in the art will be familiar with the general construction of the chamber body 101 and the use of the gas inlet and exhaust systems.

[0039] FIG. 2 is an expanded view of a portion of the backing plate 120 shown in FIG. 1 . FIG. 3 is a cross-sectional view of region III in FIG. 2 . Referring to FIGS. 1-3 , one or more specific embodiments of the present disclosure are directed to a backing plate 120 for use with a showerhead assembly 110 . The backing plate 120 has a front surface 121 and a rear surface 122 , which define a thickness T BP of the backing plate 120 .

[0040] The back plate 120 has an inner portion 124 and an outer portion 125. The back plate 120 contacts the panel 130 at the outer portion 125. The front surface 121 of the back plate 120 at the inner portion 124 has a concave shape. As shown in the figure, the concave shape of some specific embodiments has a linear slope from the inlet opening 123 to the peripheral edge 126 of the inner portion 124. In some specific embodiments, the concave shape is arcuate from the inlet opening 123 to the peripheral edge 126 of the inner portion 124.

[0041] The back plate 120 has an inlet opening 123 at its center. The inlet opening 123 extends through the thickness of the back plate 120 from the rear surface 122 to the front surface 121. The central axis 127 of the back plate 120 is defined as the center of the inlet opening 123. In some embodiments, the peripheral edge 126 of the inner portion 124 of the front surface 121 is concentric with the inlet opening 123. Although the back plate 120 of some embodiments has an oblong or asymmetrical shape, the central axis 127 is still located at the center of the inlet opening 123, even if the center is not the center of mass of the back plate 120.

[0042] The thickness T BP of the back plate 120 is measured at the peripheral edge of the back plate 120. In other words, the thickness T BP of the back plate 120 is measured at the outer portion 125 of the front surface 121 of the back plate 120 relative to the rear surface 122 of the back plate 120. In some specific embodiments, the thickness T BP of the back plate 120 is in the range of 0.5 inches to 1.5 inches, or about 1 inch.

[0043] The heater 150 is embedded within the thickness T BP of the back plate 120. The heater 150 of some embodiments is positioned within a groove 152 formed in the rear surface 122 of the back plate 120. The groove 152 of some embodiments has a depth DR, measured from the rear surface 122 of the back plate 120, and the depth DR is at least the thickness of the heater 150. In some embodiments, the depth DR of the groove 152 is in the range of 20% to 80%, or 30% to 70%, or 50% to 60% of the thickness T BP of the back plate 120.

[0044] The heater 150 can be any suitable heating mechanism known to those skilled in the art. In some embodiments, the heater 150 includes a resistive heating element. As used herein, the term "heater" is used interchangeably with "heating element," "heater element," or "heating coil" and refers to a generally annular material that generates heat when sufficient power is applied from a power source 156 via any suitable electrical connection 158.

[0045] The radius rH of the heater 150 is measured from the central axis 127 of the back plate 120 to the center of the width WH of the heating element, as shown in Figure 2. In some specific embodiments, the width WH of the heating element of the heater 150 is in the range of 1 mm to 15 mm, or in the range of 4 mm to 12 mm, or in the range of 6 mm to 10 mm.

[0046] In some embodiments, the radius r H of the heater 150 is greater than the radius r I of the inner portion 124 of the front surface 121 of the back plate 120. In some embodiments, the radius r H of the heater 150 is greater than the radius r I of the inner portion 125 of the front surface 121 of the back plate 120, so that the heater 150 is located within the outer portion 125 of the back plate 120. In other words, in some embodiments, the radius r H of the heater 150 is greater than the radius r I of the inner portion 125 of the front surface 121 of the back plate 120 plus half of the width WH of the heater 150.

[0047] To mitigate thermal non-uniformity, in some embodiments, the radius of the coil heater applied at the gas box is about 150 mm. In some embodiments, the radius r H of the heater 150 is about 150 mm, such that the center of the heater 150 is positioned above the edge of a 300 mm wafer on a substrate support within the processing chamber. In some embodiments, the radius r H of the heater 150 is greater than or equal to 150 mm, 155 mm, 160 mm, 165 mm, 170 mm, 175 mm, 180 mm, 185 mm, 190 mm, 195 mm, 200 mm, 202.5 mm, 205 mm, 207.5 mm, 210 mm, 212.5 mm, 215 mm, or 220 mm. Stated another way, in some embodiments, the centerline diameter of the heater 150 is greater than or equal to 380 mm, 390 mm, 395 mm, 400 mm, 405 mm, 410 mm, 415 mm, 420 mm, 425 mm, 430 mm, 435 mm, or 440 mm. In some embodiments, the radius r H of the heater 150 is less than 250 mm, 240 mm, or 230 mm. In some embodiments, the radius r H is in the range of 150 mm to 250 mm, or in the range of 160 mm to 240 mm, or in the range of 175 mm to 235 mm.

[0048] In some embodiments, as shown, the heater 150 is positioned in a heater recess 152 formed in the rear surface 122 of the back plate 120, and the heater 150 is covered by a heater cover 154 in the heater recess 152. The thickness T CP of the heater cover 154 of some embodiments is in the range of 1 mm to 10 mm, or in the range of 2 mm to 5 mm, or about 3 mm. The heater cover 154 of some embodiments is friction fit with the recess 152. In some embodiments, the heater cover 154 is permanently attached to the recess 152 (e.g., welded, fastened). In some embodiments, the heater element is located at a position centered on the opening 123 and having a diameter in the range of 400 mm to 440 mm.

[0049] Including the heater 150 in the rear surface 122 of the backing plate 120 can reduce the thickness of the backing plate 120. Typically, the processing chamber includes an additional cover member so that the cooling channel is embedded in the backing plate 120. By moving the heater 150 so that it is embedded in the outer portion of the backing plate 120, the cooling channel can be omitted, thereby reducing the overall thickness of the backing plate 120 without the need for an additional cover member.

[0050] FIG4 shows a partial cross-sectional view of the processing chamber 100 of FIG1 to illustrate various components. Referring to FIGS. 1 and 4, the showerhead assembly 110 includes a panel 130, which may also be referred to as a "showerhead." The panel 130 has a front surface 131 and a rear surface 132, and the front surface 131 and the rear surface 132 define a thickness TF of the panel 130. In some specific embodiments, the thickness TF of the panel 130 is approximately 1 inch.

[0051] The panel 130 has an inner portion 133 and an outer portion 134. The inner portion 133 of the panel 130 is aligned with the inner portion 124 of the back plate 120, and the outer portion 134 of the panel 130 is aligned with the outer portion 125 of the back plate 120. The inner portion 133 of the panel 130 includes a plurality of apertures 135 extending through the thickness TF of the panel 130.

[0052] FIG5 is a regional view of the panel 130 of FIG1. ​​In some embodiments, a plurality of angled openings 137 extend through the thickness of the outer portion 134 of the panel 130.

[0053] The plurality of angled openings 137 are inclined inwardly from the front surface 131 to the rear surface 132 of the panel 130. In other words, the plurality of angled openings 137 have a front surface opening 137f arranged with respect to the center with a radius r OF of the central axis 136 of the panel 130, and a rear surface opening 137b arranged with respect to the center with a radius r OB of the central axis 136, and the radius r OF is greater than the radius r OB. The central axis 136 of the panel 130 is coaxial with the central axis 127 of the back plate 120. In some specific embodiments, the diameter of the back plate is in the range of 300 mm to 320 mm, or about 310 mm.

[0054] In some embodiments, the angles of the plurality of angled openings 137 relative to the front surface 131 of the panel 130 are in a range between 75° and 15°, or in a range between 60° and 30°, or in a range between 50° and 40°.

[0055] 1, the back plate 120 can be connected to the panel 130 by any suitable mechanism known to those skilled in the art. For example, the back plate 120 can be welded to the panel 130. In some embodiments, as shown in FIG1, the back plate 120 is connected to the panel 130 using a plurality of fasteners 139. Suitable fasteners include, but are not limited to, screws.

[0056] When the front surface 121 of the outer portion 125 of the back plate 120 contacts the outer portion 134 of the rear surface 132 of the panel 130, an air box chamber 129 is formed in the space between the front surface 121 of the inner portion 124 of the back plate 120 and the inner portion 133 of the rear surface 132 of the panel 130.

[0057] In some embodiments, the gas box plenum 129 has a coating to improve chemical compatibility. In some embodiments, the coating covers the entire front surface 121 of the backing plate 120 and the entire rear surface 132 of the face plate 130, including in the inlet opening 123 of the backing plate 120 and the plurality of apertures 135 of the face plate 130. In some embodiments, the coating is only on the portions of the backing plate 120 and the face plate 130 that will come into contact with the process gas.

[0058] In some embodiments, one or more of the back plate 120 or the face plate 130 includes a material with increased emissivity, which facilitates heating of the back plate 120 or the face plate 130. In some embodiments, one or more of the back plate 120 or the face plate 130 has a coating that increases emissivity. In some embodiments, the emissivity of the coated air box plenum 129 is increased, which facilitates heating of the air box (back plate 120) and / or the face plate 130.

[0059] Some specific embodiments provide chlorine compatibility and moisture permeation improvements. Without being bound by any particular theory of operation, it is believed that the volumetric differential pumping between the dual seals and O-rings improves the chlorine compatibility and moisture permeation of the system.

[0060] Some specific embodiments of the showerhead assembly 110 further include a pumping ring 140. Referring to Figures 1 and 4, the pumping ring 140 has a front surface 141 and a rear surface 142 that define the thickness of the pumping ring 140. In use, the rear surface 142 of the pumping ring 140 is located near or in contact with the front surface 131 of the panel 130.

[0061] 1, the pumping ring 140 is connected to the back plate 120 with a plurality of fasteners 139 extending through the face plate 130. In some embodiments, the back plate 120 is fixed to the pumping ring 140 with screws, and the face plate 130 is sandwiched between the back plate 120 and the pumping ring 140.

[0062] In some embodiments, the front surface 141 of the pumping ring 140 has a groove 143 to form a pumping volume when the front surface 141 of the pumping ring 140 is adjacent to another surface. For example, as shown in FIG. 1 , when the pumping ring 140 is positioned so that the front surface 141 is adjacent to or in contact with the chamber sidewall 102 (or the pumping ring cover 117 or the choke plate 116), a pumping volume 145 is formed. In some embodiments, the pumping ring 140 includes a pumping ring cover 117 that forms the pumping volume 145 when in contact with the pumping ring 140. The pumping ring cover 117 can be a separate component on the sidewall 102 of the chamber or between the pumping ring 140 and the sidewall 102 or the choke plate 116. In the embodiment shown in FIG. 1 , the front surface 141 of the pumping ring 140 is shown in contact with the choke plate 116 with the pumping ring gasket 117 in between. In some specific embodiments, as shown in FIG. 4 , the pumping ring gasket 117 is located between the front surface 141 of the pumping ring 140 and the choke plate 116 .

[0063] At least one aperture 146 extends between the groove 143 of the front surface 141 of the pumping ring 140 and the rear surface 142 of the pumping ring 140. The radius of the at least one aperture 146 is equal to the radius of the front surface opening 137f of the angled opening 137 in the panel 130.

[0064] Surprisingly, it has been found that positioning the heating coil (heater 150) at the edge of the inner portion 124 of the backing plate 120 can reduce the temperature non-uniformity of the panel 130 by at least 25%, 30%, 35%, 36%, or 40%. In some embodiments, the design of minimal contact between the pump pad 140 and the panel 130 can reduce the showerhead temperature non-uniformity by at least 10%, 15%, 18%, 20%, or 25%. In conventional processing chambers, the contact area between the showerhead and the pumping ring is normal, and the temperature non-uniformity across the panel (measured from the center to the edge) is greater than 5.5°C or 6°C. In some embodiments, when the panel 130 is set to 150°C, the temperature non-uniformity across the panel 130 is less than or equal to 5°C, 4°C, 3.5°C, 3.25°C, 3°C, 2.5°C, or 2.3°C.

[0065] In some embodiments, the pumping ring 140 has an asymmetric shape. For example, as shown, one side or portion of the pumping ring 140 extends further from the central axis 147 of the pumping ring 140. As shown in FIG. 4 , the right side of the pumping ring 140 extends further from the central axis 147 than the left side of the pumping ring 140. In the embodiment shown in FIGS. 8A and 8B , the left side of the pumping ring 140 extends further from the central axis 147. For example, this can accommodate an exhaust groove 148 (see FIG. 4 ) that forms an exhaust plenum 149 when the pumping ring 140 is positioned on the sidewall 102 of the processing chamber body 101. The exhaust plenum 149 is connected to the pumping volume 145 via one or more exhaust channels 151. The exhaust channels 151 of some embodiments form one or more grooves or cutouts on the front surface 141 of the pumping ring 140 connecting the groove 143 with the exhaust groove 148. In some embodiments, the exhaust passage 151 is separated from the exhaust plenum 149 by a truncated wall 155 of the pumping ring 140. FIG. 8 shows a bottom view of the pumping ring 140 according to one or more embodiments of the present disclosure. In this embodiment, only the front surface 141 is shown to show the contact point with the top surface 104 of the side wall 102. The inner wall 144 of the pumping ring 140 is shown as a continuous annular hole, while the outer wall 153 is asymmetrical. The outer wall 153 extends to surround the exhaust plenum 149, and the depth of the outer wall 153 transitions to the truncated wall 155 to form one or more exhaust passages 151. The shape of the pumping ring 140 illustrated in the figure only represents one possible configuration, is used for descriptive purposes, and should not be considered to limit the scope of the present disclosure. In some embodiments, the shape of the pumping ring 140 allows a plurality of exhaust grooves 148 to be arranged symmetrically or asymmetrically around the periphery of the pumping ring 140.

[0066] The cutouts on the front surface 141 of the pumping ring 140 provide minimal contact with the sidewall 102 of the chamber body 101, which acts as a heat sink during processing. The inventors surprisingly discovered that the asymmetric minimal contact between the pumping ring 140 and the heat sink provides sufficient separation of the faceplate 130 to reduce temperature non-uniformity of the faceplate 130 during processing. The sidewall 102 of the chamber body may include a choke plate 116. The choke plate 116 of some embodiments is a separate component that mates with the chamber body and is at least partially supported by or in contact with the sidewall 102 of the chamber body 101. In some embodiments, in addition to the minimum contact between the pumping ring 140 and the faceplate 130, the pumping ring 140 and the choke plate 116 also maintain the minimal contact described herein.

[0067] During use, the backing plate 120, the face plate 130, and the pumping ring 140, as well as additional components, may be separated by one or more O-rings to help maintain a fluid seal within the processing chamber. FIG. 6 shows an expanded view of area VI of FIG. 1, showing the showerhead assembly 110. In some specific embodiments, the showerhead assembly 110 includes a plurality of O-rings positioned between the backing plate 120 and the face plate 130 and / or a plurality of O-rings positioned between the face plate 130 and the pumping ring 140.

[0068] In some specific embodiments, the showerhead assembly 110 includes an inner backing plate O-ring 160 located between the backing plate 120 and the face plate 130. The radius r160 of the inner backing plate O-ring 160 is greater than or equal to the inner sub-radius r1 of the front surface 121 of the backing plate 120.

[0069] In some specific embodiments, the showerhead assembly 110 includes an outer back plate O-ring 161 located between the back plate 120 and the face plate 130. The radius r161 of the outer back plate O-ring 161 is greater than the radius r160 of the inner back plate O-ring 160. The radius r160 of the inner back plate O-ring 160 is less than the radius rOB of the rear surface opening 137b of the angled opening 137 in the face plate 130. The radius r161 of the outer back plate O-ring 161 is greater than the radius rOB of the rear surface opening 137b of the angled opening 137 in the face plate 130.

[0070] Some specific embodiments of the showerhead assembly 110 include an inner pumping ring O-ring 162 and / or an outer pumping ring O-ring 163. The radius r162 of the inner pumping ring O-ring 162 is less than the radius r0F of the front surface opening 137f of the angled opening 137 in the panel 130. In some specific embodiments, the radius r163 of the outer pumping ring O-ring 163 is greater than the radius r0F of the front surface opening 137f of the angled opening 137 in the panel 130.

[0071] Referring again to FIGS. 1 and 4 , some embodiments of the present disclosure are directed to a semiconductor manufacturing process chamber 100 including a showerhead assembly 110 as described herein.

[0072] The substrate support 170 is located within the interior 105 of the semiconductor manufacturing process chamber 100. The substrate support 170 of some specific embodiments includes a support body 171 set on a support shaft 172. The support body 171 has a support surface 173 configured to support the semiconductor wafer 108 for processing. The support shaft 172 of some specific embodiments is configured to move the support body 171 closer to / away from the panel 130 and / or around the rotation axis of the support shaft 172. During processing, the support surface 173 is spaced from the front surface 131 of the panel 130 to form a processing gap 168.

[0073] In some embodiments, the support body 171 includes a thermal element 174 configured to heat the semiconductor wafer 108 on the support surface 173. The thermal element 174 can be any suitable heating mechanism known to those skilled in the art. For example, in some embodiments, the thermal element 174 includes a resistive heating element connected to a power source (not shown) configured to apply power to the thermal element 174 to heat the support body 171. In some embodiments, the support body 171 includes an electrostatic chuck (ESC) (not shown). Those skilled in the art will be familiar with the structure of the ESC and the power and use of the ESC.

[0074] In some specific embodiments, the semiconductor manufacturing process chamber 100 further includes an inlet flange 180 connected to the rear surface 122 of the backing plate 120. The inlet flange 180 has an inner channel 181 aligned with the opening 123 in the center of the backing plate 120. In some specific embodiments, the inner channel 181 has an upper portion 181a and a lower portion 181b. The inner diameter of the upper portion 181a is greater than the inner diameter of the lower portion 181b.

[0075] In some embodiments, the showerhead assembly 110 is positioned such that the bottom surface 141 of the pumping ring 140 contacts the top surface 104 of the chamber sidewall 102, forming the interior 105 of the processing chamber 100. In some embodiments, the top surface 104 of the chamber sidewall 102 has a choke plate 116 disposed thereon, and the pumping ring 140 contacts the choke plate 116. In some embodiments, the heater 150 within the backing plate 120 is positioned such that the heater 150 is located above the top surface 104 of the sidewall 102. Those skilled in the art will recognize that the pumping ring 140 can contact the top surface 104 of the chamber sidewall 102 through the choke plate 116, or the pumping ring 140 can contact the top surface 104 of the chamber sidewall 102 directly. When used in this manner, "direct contact" means that the components are in contact without intervening components. In some specific embodiments, the pumping ring 140 is in direct contact with the choke plate 116 , and the choke plate 116 is in direct contact with the top surface 104 of the chamber sidewall 102 .

[0076] Some embodiments of the semiconductor manufacturing process chamber 100 further include a remote plasma source (RPS) 185 connected to the inlet flange 180. In use, plasma generated in the remote plasma source 185 flows into the gas box plenum 129 through the inlet flange 180. In some embodiments, an inert gas purge line (not shown) is connected to the inner passage 181 of the inlet flange 180 to provide a continuous inert gas purge to prevent gas from flowing back into the remote plasma source 185. In some embodiments, the inert gas purge line is connected to the lower portion 181b of the inner passage 181 and is within 50 mm of the upper portion 181a of the inner passage 181. In some embodiments, the inclusion of an inert gas purge can reduce the need for an isolation valve through the continuous inert gas purge.

[0077] In some embodiments, as shown in FIGS. 1 and 4 , the semiconductor manufacturing process chamber 100 includes a radio frequency shield 190. The radio frequency shield 190 is a generally annular component positioned within the interior 105 of the semiconductor manufacturing process chamber 100 between the substrate support 170 and the sidewall 102. The radio frequency shield 190 helps prevent reactive gases from flowing from the process gap 168 to the interior 105 of the chamber body 101. However, any reactive gases that do migrate from the process gap 168 to the interior 105 can be evacuated through the chamber vacuum line (not shown).

[0078] In some embodiments of the semiconductor manufacturing process chamber 100, the front surface 141 of the pumping ring 140 has minimal contact with the chamber sidewall 102 to minimize heat transfer between the face plate 130 and the chamber sidewall 102. FIG. 8A shows an isometric view of the pumping ring 140 according to one or more embodiments of the present disclosure. FIG. 8B shows a top plan view of the pumping ring 140 of FIG. 8A. In one or more embodiments, the exhaust area AO of the pumping ring 140 occupies an area greater than or equal to 45º, 50º, 55º, 60º, 65º, 70º, or 75º of the circle formed by the pumping ring 140. The exhaust area AO is the portion of the pumping ring 140 adjacent to the chamber exhaust forming the exhaust plenum. In some embodiments, the contact area AC is present within the exhaust area AO of the pumping ring 140 for support purposes. In some embodiments, the contact area AC occupies an angular length of less than or equal to 20°, 15°, 10°, or 5° of the circle formed by the pumping ring 140 within the exhaust area AO. In some embodiments, the angular length of the exhaust area AO occupies 60° of the circle formed by the pumping ring 140, and the angular length of the contact area AC occupies 10° of the circle formed by the pumping ring 140. In some embodiments, the exhaust contact portion and the opening of the exhaust area AO are located approximately in the center of the one or more exhaust channels 151. In conventional systems, the panel loses heat to the pumping ring due to contact between components, resulting in a panel temperature non-uniformity of about 4°C. In some embodiments of the present disclosure, the non-uniformity is about 3.3°C, or less, due to minimal contact between the pumping ring and adjacent components. In some embodiments, the semiconductor manufacturing process chamber 100 does not include an additional chamber lid for maintaining temperature uniformity. In some embodiments, the reduction in thermal non-uniformity reduces the need for an additional lid heater.

[0079] 8A and 8B illustrate a top view of the pumping ring 140 according to some embodiments. In some embodiments, the bottom view of the pumping ring 140 is a mirror image of the top view, such that the open area in the contact ring 159 is located at approximately the same portion of the pumping ring 140 on the top and bottom surfaces. In some embodiments, the contact ring 159 is a separate component that is inserted into a groove formed in the top and / or bottom surfaces of the pumping ring 140. In some embodiments, the contact ring 159 is integrally formed as a part of the pumping ring 140. In some embodiments, the height of the contact ring 159 measured from the top surface 142 of the pumping ring 140 is in the range of 0.1 mm to 0.5 mm, or in the range of 0.15 mm to 0.3 mm, or about 0.2 mm. In some embodiments, the width of the contact ring 159 is in the range of 4 mm to 8 mm, or in the range of 5 mm to 7 mm, or about 6 mm.

[0080] In some specific embodiments, minimum contact rings are formed between pumping ring gasket 117 and pumping ring 140 and between pumping ring gasket 117 and choke plate 116 .

[0081] In some embodiments, as shown in FIG. 9A , the top surface 116a of the choke plate 116 includes a plurality of standoffs 192 disposed around the periphery of the choke plate 116. The standoffs 192 in some embodiments are small bumps formed on the surface of one or more components such that, when positioned adjacent to another component, contact between the components is limited to the top of the standoffs 192. FIG. 9B shows the bottom surface 116b and inner flange 116c of the choke plate 116. The plurality of standoffs 192 are shown on the bottom surface 116b of the choke plate 116 outside the diameter of the inner flange 116c. Although FIGS. 9A and 9B illustrate an annular choke plate 116, those skilled in the art will recognize that other shapes of choke plates are also within the scope of the present disclosure.

[0082] The number of standoffs 192 may be determined based on factors such as the size and structural material of the choke plate 116. In the illustrated embodiment, there are six standoffs 192 on each of the top surface 116a and the bottom surface 116b of the choke plate 116. In some embodiments, there are three, four, five, six, seven, eight, nine, ten, eleven, twelve or more standoffs independently on the top surface 116a and the bottom surface 116b of the choke plate 116. The size of the standoffs 192 may be configured to maintain minimal contact between adjacent components.

[0083] In some embodiments, minimal contact is formed between the top surface of the choke plate 116 and the bottom surface of the pumping liner cover 117. In some embodiments, minimal contact is formed between the bottom surface of the choke plate 116 and the top surface of the chamber wall 102. In some embodiments, minimal contact is formed between the choke plate 116 and the chamber wall 102 and the pumping liner cover 117 and / or the pumping liner 140.

[0084] In an exemplary four-station chamber, the edge temperature uniformity is lower than the center temperature uniformity due to the showerhead conducting heat to the chamber through the pump pad. To mitigate the thermal non-uniformity, a minimum contact is used on the pump pad to minimize the conduction heat from the showerhead to the pump pad. In some specific embodiments, the minimum contact is greater than 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, or 0.3 mm in the edge contact area.

[0085] Some embodiments of the present disclosure are directed to a multi-station processing chamber. For example, as shown in FIG. 7 , the multi-station processing chamber 200 includes more than one semiconductor manufacturing processing chamber 100. In some embodiments, the multi-station processing chamber 200 includes four stations. In some embodiments, the four stations generate thermal non-uniformity toward the pumping port on each station. Minimum contact results in a height or gap between the pumping ring and adjacent components of between 0.1 mm and 0.3 mm.

[0086] Embodiments of the present disclosure provide processing chambers and showerheads for processing chambers that can utilize existing station structures to achieve plasma enhanced gap filling of molybdenum with minimal design changes and reduced costs. Embodiments of the present disclosure improve the gap filling process by reducing the size of the processing gap, thereby achieving faster cycle times, better thermal uniformity, and higher plasma stability.

[0087] References throughout this specification to "one embodiment", "some embodiments", "one or more embodiments" or "an embodiment" mean that a particular feature, structure, material or characteristic associated with an embodiment is included in at least one embodiment of the present disclosure. Therefore, phrases such as "in one or more embodiments", "in some embodiments", "in one embodiment" or "in an embodiment" appearing throughout this specification do not necessarily refer to the same embodiment of the present disclosure. Furthermore, specific features, structures, materials or characteristics may be combined in any suitable manner in one or more embodiments.

[0088] Although the disclosure herein has been described with reference to specific embodiments, it will be understood by those skilled in the art that the described embodiments are merely illustrative of the principles and applications of the disclosure. It is apparent to those skilled in the art that various modifications and variations may be made to the methods and apparatus of the disclosure without departing from the spirit and scope of the disclosure. Therefore, the disclosure may include modifications and variations within the scope of the appended claims and their equivalents.

[0089] 100: Semiconductor manufacturing processing chamber 102: Side wall 103: Bottom wall 104: Top surface 105: Interior 110: Sprinkler head assembly 116: Choke plate 116a: Top surface 116b: bottom surface 116c: Inner flange 117: Pumping liner cover 120: Back panel 121: front surface 122: Rear surface 123: Entrance opening 124: Internal part 125: External part 126: Peripheral edge 127: Central axis 129: Air box chamber 130: Panel 131: front surface 132: Rear surface 133: Internal part 134: External part 135: Porosity 136: Central axis 137: Bevel opening 137b: Rear surface opening 137f: front surface opening 139: Fasteners 140: Pumping ring 141: front surface 142: Rear surface 143: Groove 144: Inner wall 145: Pumping volume 146: Porosity 147:Central axis 148: Exhaust groove 149: Exhaust chamber 150: Heater 151: Exhaust channel 152: Groove 153:Outer wall 154: Heater cover 155: Truncated wall 156: Power Supply 158: Electrical connection lines 159: Contact ring 160: Inner back plate O-ring 161: Outer back plate O-ring 162: Inner pumping ring O-ring 163: Outer pumping ring O-ring r160: radius r161: radius r162: radius r163: radius 168: Processing gap 170: Base plate support 180: Inlet flange 181: Inner Passage 181a: upper part 181b: Lower part 185: Remote Plasma Source (RPS) 190: RF shielding 192:Support 200:Multi-station processing chamber

Claims

1. A spray head assembly for use in a semiconductor manufacturing process chamber, the spray head assembly comprising: A backplate having a front surface and a rear surface defining a thickness of the backplate, an inlet opening at a center of the backplate extending through the thickness of the backplate, the backplate having an outer portion and an inner portion, the front surface of the inner portion having a concave shape; a heater embedded within the thickness of the backplate, the heater having a circular shape, a radius of which is measured from a central axis of the backplate, the radius of which is larger than a radius of the inner portion of the backplate, such that the heater is located within the outer portion of the backplate; and a panel having a front surface and a rear surface defining a thickness of the panel, the panel having an inner portion and an outer portion, a plurality of apertures extending through the thickness of the panel in the inner portion, a plurality of beveled openings extending through the thickness of the outer portion of the panel, the plurality of beveled openings having a front surface opening arranged relative to a center with a radius of a central axis of the panel, the radius of which is larger than the central radius of a rear surface opening.

2. The spray head assembly as claimed in claim 1, wherein a radius of the heater is between 175 mm and 235 mm.

3. The spray head assembly as claimed in claim 2, wherein the heater is positioned in a heater recess formed in the rear surface of the back plate, and the heater is covered in the heater recess by a heater cover plate.

4. The spray head assembly as claimed in claim 1, wherein the back plate is connected to the panel by a plurality of fasteners.

5. The spray head assembly as claimed in claim 4, the spray head assembly further comprising an inner back plate O-ring located between the back plate and the front plate, the radius of the inner back plate O-ring being greater than or equal to a radius of the inner portion of the front surface of the back plate.

6. The spray head assembly as claimed in claim 5, the spray head assembly further comprising a pumping ring having a rear surface and a front surface, the rear surface and the front surface defining a thickness of the pumping ring, the rear surface of the pumping ring being adjacent to the front surface of the panel.

7. The spray head assembly as claimed in claim 6, wherein the back plate is screwed to the pumping ring, and the panel is sandwiched between the back plate and the pumping ring.

8. The spray head assembly as described in claim 7, further comprising: An outer backplate O-ring is positioned between the backplate and the panel. The radius of the outer backplate O-ring is greater than the radius of the inner backplate O-ring, which is smaller than the radius of the rear surface opening of the beveled openings in the panel. The radius of the outer backplate O-ring is also greater than the radius of the rear surface opening of the beveled openings in the panel. Additionally, an inner pumping ring O-ring and an outer pumping ring O-ring are provided. The radius of the inner pumping ring O-ring is smaller than the radius of the front surface opening of the beveled openings in the panel, which is larger than the radius of the front surface opening of the beveled openings in the panel.

9. The spray head assembly as claimed in claim 8, wherein the front surface of the pumping ring has a groove to form a pumping volume when the front surface of the pumping ring adjoins another surface, and at least one aperture extends between the groove in the front surface of the pumping ring and the rear surface of the pumping ring, the radius of the at least one aperture being equal to the radius of the front surface opening of the beveled opening in the panel.

10. A semiconductor manufacturing processing chamber, comprising: The spray head assembly as described in claim 9; An inlet flange connected to the rear surface of the backplate, the inlet flange having an inner channel aligned with an opening in the center of the backplate, the inner channel having an upper portion and a lower portion, the inner diameter of the upper portion being larger than the inner diameter of the lower portion; a chamber sidewall and a chamber bottom, the spray head assembly being positioned such that the front surface of the pumping ring and a top surface of the chamber sidewall form an interior of the processing chamber; and a substrate support within the processing chamber, the substrate support having a support surface configured to support a wafer during processing, the support surface being spaced apart from the front surface of the panel to form a processing gap.

11. The semiconductor manufacturing process chamber as claimed in claim 10, wherein the heater is located above the top surface of the sidewall of the chamber.

12. The semiconductor manufacturing process chamber as described in claim 10, the semiconductor manufacturing process chamber further comprising a distal plasma source (RPS) connected to the inlet flange.

13. The semiconductor manufacturing process chamber as claimed in claim 10, wherein a choke is provided between the front surface of the pumping ring and the chamber sidewall to minimize heat transfer between the panel and the chamber sidewall.

14. The semiconductor manufacturing process chamber as described in claim 13, wherein no additional chamber cover is required to maintain temperature uniformity.

15. The semiconductor manufacturing processing chamber as described in claim 14, wherein the thermal non-uniformity of the panel is less than 3.5ºC.

16. A spray head assembly for use in a semiconductor manufacturing process chamber, the spray head assembly comprising: A backplate having a heater embedded in a thickness thereof, an inlet opening at a center of the backplate extending through the thickness thereof, an inner portion of a front surface of the backplate having a concave shape, and a radius of the heater being larger than the radius of the inner portion of the front surface; a panel having a plurality of holes extending through a thickness thereof in an inner portion thereof, and a plurality of beveled openings extending through the thickness thereof in an outer portion thereof; and a pumping ring connected to the backplate by a plurality of fasteners extending through the panel.

17. The spray head assembly as claimed in claim 16, wherein a radius of the heater is greater than 175 mm.

18. The spray head assembly as claimed in claim 17, wherein the heater is positioned in a heater recess formed in a rear surface of the back plate, and the heater is covered in the heater recess by a heater cover plate.

19. The spray head assembly as claimed in claim 18, the spray head assembly further comprising a plurality of O-rings positioned between the back plate and the front panel, and a plurality of O-rings positioned between the front panel and the pumping ring.

20. A semiconductor manufacturing processing chamber, comprising: A chamber sidewall and a chamber bottom; a spray head assembly as claimed in claim 19, the spray head assembly being positioned on the chamber sidewall to enclose an interior of the processing chamber, the heater being positioned above the chamber sidewall.

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