Process accessory geometries for particle reduction in PVD processes

Abstract

A process accessory includes a shield and a ring assembly for positioning around a substrate support in a process chamber to reduce deposition of process deposits on overhanging edges of internal chamber components and substrates. The shield includes a cylindrical band having an inclined portion of a top wall and a bottom wall, the top wall being configured to surround a sputtering target, the inclined portion of the bottom wall having a substantially straight profile, having gas conducting holes and being configured to surround the substrate support. The ring assembly includes a cover ring having a spherical protrusion around the periphery of the ring. The spherical protrusion of the cover ring is capable of blocking a line of sight between the gas conducting holes on the shield and an entrance to a chamber body cavity in the process chamber.

Description

Technical Field

[0001] Embodiments of the present principles relate generally to semiconductor processing and, more particularly, to process kit geometries for particle reduction in physical vapor deposition processes. Background Art

[0002] In the manufacture of integrated circuits and displays, a substrate such as a semiconductor wafer or a display panel is placed in a substrate processing chamber, and processing conditions are set in the chamber to deposit or etch material on the substrate. A typical processing chamber includes chamber components, which include: a housing wall that surrounds a processing area; a gas source to provide a processing gas in the chamber; a gas energizer to energize the processing gas to process the substrate; a gas exhaust device to remove the exhaust gas and maintain the gas pressure in the chamber; and a substrate support for holding the substrate. Such chambers may include, for example, sputtering (PVD), chemical vapor deposition (CVD), and etching chambers. In a PVD chamber, a target is sputtered by an excited gas to sputter a target material, which is then deposited on a substrate facing the target.

[0003] In the sputtering process, material sputtered from the target is also deposited on the edges of the chamber components surrounding the target, which is undesirable. The peripheral target area has a dark space region where sputtered material is redeposited due to ion scattering in the dark space region. The accumulation and buildup of sputtered material in the dark space region is undesirable because such accumulated deposits require the target and surrounding components to be disassembled and cleaned or replaced, may cause plasma shorting, and may cause arcing between the target and the chamber wall. These deposits also often break away and peel off due to thermal stresses to fall into the interior and contaminate the chamber and related components.

[0004] Process accessories, including shields and cover rings disposed around substrate supports and chamber sidewalls, are often used to receive excess sputtered material to protect chamber walls and other component surfaces and prevent deposition thereon. Disclosed herein are process accessory components that are shaped and arranged in relation to one another to reduce the amount of sputtered deposits formed on interior surfaces of a processing chamber and to reduce flaking of sputtered deposits. Summary of the invention

[0005] Embodiments of process kit shields and process kit geometries for particle reduction in physical vapor deposition processes are disclosed herein.

[0006] In some embodiments according to the principles of the present invention, a shield for surrounding a sputtering target (the sputtering target faces a substrate support in a substrate processing chamber) includes: a cylindrical belt having a top wall configured to surround the sputtering target and a bottom wall configured to surround the substrate support; an inclined wall extending downwardly and radially inwardly from the bottom wall of the cylindrical belt, the inclined wall having a substantially straight profile; and at least one gas hole located on the inclined wall, the at least one gas hole allowing a processing gas to pass therethrough.

[0007] In some embodiments according to the principles of the present invention, a processing accessory for placement around a sputtering target and a substrate support in a substrate processing chamber includes a shield and a ring assembly, the shield being configured to surround the sputtering target. In some embodiments, the shield includes: a cylindrical belt having a top wall configured to surround the sputtering target and a bottom wall configured to surround the substrate support; an inclined wall extending downwardly and radially inwardly from the bottom wall of the cylindrical belt, the inclined wall having a substantially straight profile; and at least one gas hole located on the inclined wall, the at least one gas hole allowing a process gas to pass therethrough.

[0008] In some embodiments, the ring assembly includes a cover ring configured to surround the substrate support, the cover ring comprising: an annular wedge, the annular wedge comprising an inclined top surface surrounding the substrate support, the inclined top surface having an inner periphery and an outer periphery; a spherical protrusion surrounding the outer periphery of the inclined top surface; a base extending downward from the inclined top surface; a protruding edge surrounding the inner periphery of the inclined top surface; and an inner cylindrical band and an outer cylindrical band extending downward from the annular wedge.

[0009] In some embodiments, the spherical protrusion of the cover ring blocks a line of sight between the at least one air hole on the shield and an entrance to a chamber body cavity in a substrate processing chamber.

[0010] In some embodiments according to the principles of the present invention, an apparatus for processing a substrate includes: a processing chamber having a processing cavity and a chamber body cavity; a substrate support disposed in the processing cavity; a target disposed in the processing cavity and opposite to the substrate support; and a processing accessory located around the substrate support and the target.

[0011] In some embodiments, the process assembly includes a shield and a ring assembly, the shield surrounding the target. In some embodiments, the shield includes: a cylindrical belt having a top wall surrounding the sputtering target and a bottom wall surrounding the substrate support; an inclined wall extending radially inward from the bottom wall of the cylindrical belt, the inclined wall having a substantially straight profile; and at least one gas hole located on the inclined wall, the at least one gas hole allowing a process gas to pass therethrough.

[0012] In some embodiments, the ring assembly includes a cover ring, which is positioned around the substrate support, and the cover ring includes: an annular wedge, the annular wedge including an inclined top surface surrounding the substrate support, the inclined top surface having an inner periphery and an outer periphery; a spherical protrusion surrounding the outer periphery of the inclined top surface; a base extending downward from the inclined top surface; a protruding edge surrounding the inner periphery of the inclined top surface; and an inner cylindrical band and an outer cylindrical band extending downward from the annular wedge.

[0013] In some embodiments, the spherical protrusion of the cover ring blocks a line of sight between the at least one air hole on the shield and an entrance to a chamber body cavity in a substrate processing chamber.

[0014] Other and further implementations of the present principles are described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Embodiments of the present principles, briefly summarized above and discussed in more detail below, may be understood by reference to the illustrative embodiments of the principles depicted in the accompanying drawings. However, the drawings illustrate only typical embodiments of the present principles and are therefore not to be considered limiting of scope, as the present principles may admit to other equally effective embodiments.

[0016] Figure 1 Depicted is a high-level block diagram of a substrate processing chamber according to an embodiment of the present principles.

[0017] Figure 2 Describes an embodiment according to the present principles Figure 1 A perspective view of a substrate processing chamber and a process assembly within the substrate processing chamber having a shield and a ring assembly.

[0018] Figure 3A A graph of gas flow rates for a substrate processing chamber using a best-known method (BKM) generated using computer-aided engineering (CAE) analysis is depicted.

[0019] Figure 3BDepicted is a graph of gas flow rates for a substrate processing chamber, according to an embodiment of the present principles.

[0020] Figure 4 Describes an alternative embodiment according to the present principles Figure 1 A perspective view of a substrate processing chamber and a process assembly within the substrate processing chamber having a shield and a ring assembly.

[0021] For ease of understanding, the same reference numerals are used where possible to represent the same elements common to the figures. The drawings are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be advantageously incorporated into other embodiments without further description. DETAILED DESCRIPTION

[0022] In the following detailed description, many specific details are set forth in order to provide a thorough understanding of the exemplary embodiments or other examples described herein. However, these embodiments and examples may be implemented without these specific details. In addition, the disclosed embodiments are for exemplary purposes only, and other embodiments may be used in place of the disclosed embodiments or in combination with the disclosed embodiments.

[0023] Figure 1 A high-level block diagram depicting a substrate processing chamber according to an embodiment of the present principles. The substrate processing chamber 100 is representative of a CLEAN W.TM. chamber available from Applied Materials Inc. of Santa Clara, Calif. However, other processing chambers may also be used in conjunction with the present principles. Figure 1 The substrate processing chamber 100 illustratively includes an enclosure wall 106 that surrounds a processing cavity 108. The wall 106 includes sidewalls 116, a bottom wall 120, and a top plate 124. The substrate processing chamber 100 may be part of a multi-chamber platform (not shown) having a cluster of interconnected chambers connected by a substrate transfer mechanism (e.g., a robotic arm) that transfers the substrate 104 between the chambers. Figure 1 In the illustrated embodiment, the substrate processing chamber 100 is illustratively a sputtering deposition chamber, also known as a physical vapor deposition chamber or PVD chamber, which is capable of sputtering depositing materials onto a substrate 104, such as one or more of aluminum, copper, tantalum, tantalum nitride, titanium, titanium nitride, tungsten, and tungsten nitride.

[0024] The substrate processing chamber 100 includes a substrate support 130 including a pedestal 134 that supports a substrate 104. The pedestal 134 has a substrate receiving surface 138 having a plane substantially parallel to a sputtering surface 139 of an upper sputtering target 140. The substrate receiving surface 138 of the pedestal 134 receives and supports the substrate 104 during processing. The pedestal 134 may include an electrostatic chuck or a heater, such as a resistive heater or a heat exchanger. In operation, the substrate 104 is introduced into the substrate processing chamber 100 through a substrate loading inlet 142 in a sidewall 116 of the substrate processing chamber 100 and is placed onto the substrate support 130. The support 130 may be raised or lowered by a support lifting bellows, and a lifting finger assembly may be used to lift and lower the substrate 104 onto the support 130 during placement of the substrate 104 on the substrate support 130 by a robotic arm. The pedestal 134 may be maintained at an electrically floating potential or at ground during plasma operation.

[0025] Figure 2 Describes an embodiment according to the present principles Figure 1 1 is a perspective view of a substrate processing chamber 100 including a processing assembly 200. Figure 1 and Figure 2 , the sputtering target 140 includes a sputtering plate 280 mounted to a backing plate 284. The sputtering plate 280 includes a material to be sputtered onto the substrate 104. The sputtering plate 280 may include a central cylindrical table 286 having a sputtering surface 139 that forms a plane parallel to the plane of the substrate 104. An annular beveled edge 288 surrounds the cylindrical table 286. The annular edge 288 may be inclined at an angle of at least about 80 degrees relative to the plane of the cylindrical table 286, for example, about 100 degrees to about 200 degrees.

[0026] The complex shape of the annular beveled edge 288 and the sidewalls adjacent to the top wall 216 of the shield 201 in the substrate processing chamber 100 form a spiral gap 300 including a dark space region; the dark space region is a region that is highly depleted of free electrons and can be modeled as a vacuum. The dark space region is controlled to prevent plasma ingress, arcing, and instability. The shape of the gap 300 acts as a maze that impedes the passage of sputtered plasma species through the gap 300, thereby reducing the accumulation of sputtered deposits on the surface of the surrounding target area.

[0027] The backing plate 284 has a support surface 303 to support the sputtering plate 280 and a peripheral ledge 304 that extends beyond the radius of the sputtering plate 280. The peripheral ledge 304 of the backing plate 284 includes an outer footing 308 that is seated on an isolator 310 in the substrate processing chamber 100. The peripheral ledge 304 includes an O-ring groove 312 in which an O-ring 314 is placed to form a vacuum seal. The isolator 310 electrically isolates and separates the backing plate 284 from the substrate processing chamber 100 and is typically a ring formed of a dielectric or insulating material such as aluminum oxide. The peripheral ledge 304 is shaped to inhibit the flow or migration of sputtering materials and plasma species through the gap 300 between the target 140 and the isolator 310 to prevent sputtering deposits from penetrating into the gap 300.

[0028] The sputtering target 140 is connected to a target power supply 320, which applies a bias voltage to the target 140. When the target power supply 320 supplies power to the target 140, the gas energizer 324 energizes the sputtering gas to form a plasma of the sputtering gas. The gas energizer 324 may include a source coil 326, which is powered by applying a current through the coil 326. The formed plasma strikes and bombards the sputtering surface 139 of the target 140 with energy, so that material is sputtered from the sputtering surface 139 onto the substrate 104.

[0029] The substrate processing chamber 100 may include a magnetic field generator 330 to shape a magnetic field around the target 140 to improve sputtering of the target 140. Capacitively generated plasma may be enhanced by the magnetic field generator 330, wherein, for example, a permanent magnet or electromagnetic coil may provide a magnetic field having a rotating magnetic field in the substrate processing chamber 100, the rotating magnetic field having an axis that rotates parallel to the plane of the substrate 104. The magnetic field generator 330 may generate a magnetic field near the target 140 of the substrate processing chamber 100 to increase the ion density in a high density plasma region adjacent to the target 140, thereby improving sputtering of the target 140 material. The magnetic field extends through the substantially non-magnetic target 140 into the substrate processing chamber 100.

[0030] The sputtering gas is introduced into the substrate processing chamber 100 by a gas delivery system 332 which provides gas from a gas source 334 via a conduit 336 having a gas flow control valve 338 (e.g., a mass flow controller) to pass a set flow rate of gas therethrough. The gas is fed to a mixing manifold (not shown) where the gas is mixed to form a desired process gas composition and fed to a gas distributor 340 having a gas outlet for introduction of the gas into the substrate processing chamber 100. The process gas may include a non-reactive gas, such as argon or xenon, which is capable of energetically impacting the target 140 and sputtering material from the target 140. The process gas may also include a reactive gas, such as one or more of an oxygen-containing gas and a nitrogen-containing gas, which is capable of reacting with the sputtering material to form a layer on the substrate 104. The gas is then excited by a gas energizer 324 to form a plasma to sputter the sputtering target 140. The waste process gas and byproducts are exhausted from the substrate processing chamber 100 through an exhaust system 342. The exhaust system 342 includes an exhaust port 344 that receives the waste process gas and delivers the exhaust gas to an exhaust conduit 346 having a throttle valve to control the gas pressure in the substrate processing chamber 100. The exhaust conduit 346 is connected to one or more exhaust pumps 348.

[0031] The substrate processing chamber 100 may be controlled by a controller 350 including program code having an instruction set to operate components of the substrate processing chamber 100 to process the substrate 104. For example, the controller 350 may include program code including: a substrate positioning instruction set to operate the substrate support 130 and the substrate transfer mechanism; a gas flow control instruction set to operate the gas flow control valve to set the sputtering gas flow to the substrate processing chamber 100; a gas pressure control instruction set to operate the exhaust throttle valve to maintain the pressure in the substrate processing chamber 100; a gas energizer control instruction set to operate the gas energizer 324 to set the gas energization power level; and a process monitoring instruction set to monitor the process in the substrate processing chamber 100.

[0032] exist Figure 1 and Figure 2 In an embodiment of the present invention, the process kit 200 includes a shield 201 and a ring assembly 202 to be placed around a peripheral wall 204 of a substrate support 130, the peripheral wall 204 terminating before an overhanging edge 206 of the substrate 104. The ring assembly 202 includes a deposition ring 208 and a cover ring 212. The deposition ring 208 includes an annular band 215 surrounding the support 130. The cover ring 212 at least partially covers the deposition ring 208. The deposition ring 208 and the cover ring 212 cooperate with each other to reduce the formation of sputtered deposits on the peripheral wall 204 of the support 130 and the overhanging edge 206 of the substrate 104.

[0033] like Figure 2 As shown and as described above, the deposition ring 208 includes an annular band 215 that extends around and surrounds the peripheral wall 204 of the support 130. The annular band 215 includes an inner lip 250 that extends laterally from the annular band 215 and is substantially parallel to the peripheral wall 204 of the support 130. The inner lip 250 terminates immediately below the overhanging edge 206 of the substrate 104. The inner lip 250 defines the inner perimeter of the deposition ring 208, which surrounds the perimeter of the substrate 104 and the substrate support 130 to protect areas of the substrate support 130 that are not covered by the substrate 104 during processing. For example, the inner lip 250 surrounds and at least partially covers the peripheral wall 204 of the support 130 that is otherwise exposed to the processing environment to reduce or even completely eliminate the deposition of sputtered deposits on the peripheral wall 204. The deposition ring 208 may also be used to protect the exposed side surfaces of the support 130 to reduce erosion by excited plasma species.

[0034] exist Figure 1 and Figure 2 In the illustrated embodiment, the annular band 215 of the deposition ring 208 has a semicircular protrusion 252 extending along a central portion of the annular band 215 with radially inward recesses 254a, 254b on either side of the semicircular protrusion 252. The radially inward recess 254a is spaced from the cover ring 212 to form an arcuate gap 256 therebetween, which acts as a labyrinth to reduce penetration of plasma species into the arcuate gap 256. An open internal passage 258 is located between the inner lip 250 and the semicircular protrusion 252. The open internal passage 258 extends radially inwardly and terminates at least partially below the overhanging edge 206 of the substrate 104. The open internal passage 258 facilitates removal of sputtered deposits from these portions during cleaning of the deposition ring 208. The deposition ring 208 also has a protrusion 260 extending outwardly and located radially outward of the semicircular protrusion 252. The protrusion 260 is used to support the cover ring 212 .

[0035] like Figure 2 As shown and described above, the cover ring 212 surrounds and at least partially covers the deposition ring 208 to receive a majority of the sputtered deposits and thus shield the deposition ring 208 from a majority of the sputtered deposits. The cover ring 212 includes an annular wedge 262 including an inclined top surface 264 that is inclined radially inward and surrounds the substrate support 130. The angle of the inclined top surface 264 of the cover ring 212 is designed, for example, to minimize the accumulation of sputtered deposits proximate the overhanging edge 206 of the substrate 104, which would otherwise negatively impact the deposition uniformity obtained across the substrate 104.

[0036] The inclined top surface 264 of the annular wedge 262 has an inner periphery 266 and an outer periphery 268. The inner periphery 266 includes a protruding edge 270 that covers the radially inward recess 254a that includes the open interior passage 258 of the deposition ring 208. The protruding edge 270 reduces the deposition of sputtered deposits on the open interior passage 258 of the deposition ring 208. The protruding edge 270 protrudes a distance corresponding to at least about half the width of the arcuate gap 256 formed with the deposition ring 208. The protruding edge 270 is sized, shaped, and positioned to cooperate with and complement the arcuate gap 256 to form a convoluted and converging flow path between the cover ring 212 and the deposition ring 208 that inhibits process deposits from flowing onto the peripheral wall 204. The constricted flow path of the narrow gap 256 limits the accumulation of low energy sputtered deposits on the mating surfaces of the deposition ring 208 and the cover ring 212 , which could otherwise cause the deposition ring 208 and the cover ring 212 to adhere to each other or to the peripheral overhanging edge 206 of the substrate 104 .

[0037] Around the outer periphery 268 of the inclined top surface 264 is a spherical protrusion 272. Figure 2 In the embodiment of the present invention, the spherical protrusion 272 includes an elliptical circumferential surface 274 , and the elliptical circumferential surface 274 forms an arc-shaped gap with the shielding member 201 .

[0038] The cover ring 212 includes a footing 276 extending downward from the inclined top surface 264 of the annular wedge 262 to rest on the protrusion 260 of the deposition ring 208. The footing 276 extends downward from the wedge 262 to substantially press against the deposition ring 208 without cracking or breaking the deposition ring 208. The cover ring 212 further includes an inner cylindrical band 278a and an outer cylindrical band 278b extending downward from the annular wedge 262 with a gap therebetween. In some embodiments, the inner cylindrical band 278a and the outer cylindrical band 278b are substantially vertical. The cylindrical bands 278a, 278b are located radially outward of the footing 276 of the wedge 262. The inner cylindrical band 278a has a height less than the outer cylindrical band 278b.

[0039] The cover ring 212 may be adjustable and effective to shield the gas conducting holes 249 of the shield 201 at different height ranges. For example, the cover ring 212 can be raised and lowered to adjust the height of the cover ring 212 relative to the substrate support 130 in the chamber.

[0040] like Figure 2As shown, the shield 201 of the processing kit 200 surrounds the sputtering surface 139 of the sputtering target 140 facing the substrate support 130 and the outer periphery of the substrate support 130. The shield 201 covers and shields the sidewalls 116 of the substrate processing chamber 100 to reduce the deposition of sputtering deposits originating from the sputtering surface 139 of the sputtering target 140 onto components and surfaces behind the shield 201. For example, the shield 201 can protect the surfaces of the support 130, the overhanging edge 206 of the substrate 104, the sidewalls 116 and the bottom wall 120 of the substrate processing chamber 100.

[0041] exist Figure 2 In the illustrated embodiment, the shield 201 includes a cylindrical band 214 having a diameter sized to surround the sputtering surface 139 of the sputtering target 140 and the substrate support 130. The cylindrical band 214 has a top wall 216 that surrounds the sputtering surface 139 of the sputtering target 140. An annular adapter 226 of the shield 201 surrounds the sidewall 116 of the substrate processing chamber 100. A plurality of pins 230 are spaced and positioned along the adapter 226 along a circle or circular arrangement. In some embodiments, at least three pins 230 are positioned along a circle on the adapter 226. Each pin 230 may include a rigid member constructed of a material such as steel or such as stainless steel.

[0042] The shield 201 includes a bottom wall 242 that surrounds the substrate support 130. An inclined wall 244 extends inwardly from the bottom wall 242 of the cylindrical belt 214 and surrounds the substrate support 130. Figure 2 In the illustrated embodiment, the angled wall 244 includes a substantially straight profile. That is, the inventors determined that if the angled wall 244 includes a substantially straight profile, the flaking of sputtered material deposited on the shield 201 is reduced compared to a BKM processing chamber that includes an angled step in the lower portion of the shield. Therefore, making the angled wall 244 straighter than the angled step reduces the flaking of sputtered material deposited on the shield 201.

[0043] The angled wall 244 of the shield 201 forms an outer leg of a channel 246 having at least one gas conduction hole 249 to allow process gas to pass therethrough. The channel 246 also includes an inner second leg 253 spaced from the angled wall 244. The shield 201 allows gas from the substrate processing chamber 100 to pass through the gas conduction hole 249 and circulate through the channel 246 into the processing cavity 108 (e.g., the processing volume). Although Figure 2 In the embodiment depicted in FIG. 1 , the gas conducting holes 249 in the inclined wall 244 are substantially rectangular, but in other embodiments according to the present principles, the gas conducting holes in the inclined wall 244 can be defined as substantially any shape. Figure 2 In the depicted embodiment, the gas conduction holes 249 are illustratively located in the middle portion of the inclined wall 244, but in alternative embodiments, the gas conduction holes 249 may be located substantially anywhere along the inclined wall 244, so long as the cover ring 212 prevents the gas passing through the gas conduction holes 249 of the shield 201 from having a direct line of sight to the gap 300. For example, in some embodiments, the gas conduction holes 249 may be located in the lower portion of the inclined wall 244.

[0044] According to an embodiment of the present principles, the spherical protrusions 272 of the cover ring 212, the angle and length of the inclined wall 244 of the shield 201, and the size, shape, and location of the gas conduction holes 249 on the shield 201 are designed and cooperate to reduce the flaking of sputtered materials deposited on the process accessory components and block the line of sight of deposits from leaving the process cavity 108 and entering the chamber body cavity (e.g., non-processing space). More specifically, the spherical protrusions 272 of the cover ring 212, the angle and length of the inclined wall 244 of the shield 201, and the shape and location of the gas conduction holes 249 on the shield 201 are designed to reduce the flaking of sputtered deposits on the process accessory components and prevent the gas passing through the gas conduction holes 249 of the shield 201 from having a direct line of sight to the gap 300 between the target 140 and the isolator 310, confining the plasma in the process cavity 108, and thereby preventing the sputtered deposits carried by the plasma from entering the gap 300.

[0045] The inventors determined that if the inclined wall 244 includes a substantially straight profile, flaking of sputtered material deposited on the shield 201 will be reduced. More specifically, making the inclined wall 244 in the lower portion of the shield 201 substantially straight results in a better adhesion of the film of sputtered deposits to the shield 201 and less flaking of the sputtered deposits. The inventors further determined that the inclined wall 244 must be angled so that the protrusion 272 of the cover ring 212 can block the line of sight between the gas conduction holes 249 of the shield 201 and the gap 300, which is located between the target 140 and the spacer 310. In addition, the length of the inclined wall 244 must be such that the gas conduction holes 249 can be located on the inclined wall 244 so that the line of sight between the gas conduction holes 249 of the shield 201 and the gap 300, which is located between the target 140 and the spacer 310, can be blocked by the protrusion 272 of the cover ring 212. In some embodiments according to the present principles, the gas conduction holes 249 are located on the inclined wall 244 of the shield 201 at a position generally lower than the gas conduction of the BKM process assembly, and thus the gas conduction holes 249 are located closer to the cover ring 212. In one embodiment, a process assembly according to the present principles includes a shield 201 having a conduction hole 249 having a width of about 0.45 inches, such as from about 0.2 inches to about 0.8 inches, and a length of about 1.6 inches, such as from about 1 inch to about 2 inches. The shield 201 may also include an inclined wall 244 having an angle of about 25 degrees, such as from about 15 degrees to about 45 degrees. With this configuration, the process assembly 200 according to the present principles results in less flaking of sputtered deposits from the shield 201. Furthermore, the line of sight between the gas conducting holes 249 of the shield 201 and the gap 300 (which is located between the target 140 and the spacer 310 ) is blocked by the spherical protrusions 272 of the cover ring 212 , thereby preventing the sputtered deposits carried by the plasma from entering the gap 300 .

[0046] exist Figure 2 In FIG. 1 , a dashed line 299 represents a line of sight between the gas conducting hole 249 of the shield 201 and the gap 300, the dashed line 299 originating from the gap 300 between the target 140 and the spacer 310 and extending toward the protrusion 272 of the cover ring 212. Figure 2 As shown, the spherical protrusion 272 of the cover ring 212, the angle and length of the inclined wall 244 of the shield 201, and the gas conduction holes 249 on the shield 201 are shaped and arranged in relation to each other to block the line of sight between the gas conduction holes 249 of the shield 201 and the gap 300 (which is located between the target material 140 and the insulator 310) and reduce the peeling of sputtered deposits on at least the shield 201.

[0047] In the process kit 200 according to the present principles, the gas conduction holes 249 are located at a lower position on the shield 201 and on the inclined wall 244 of the shield 201, which is different from the process kit of the best known method (BKM) in which the conduction holes are parallel to the surface of the cylindrical belt 214 and located at a higher position on the shield. The geometry of the process kit 200 according to the present principles requires that the liner 203 of the process kit 200 extends farther inward to contain the plasma. That is, returning to the reference Figure 2 , the processing accessory 200 may further include a pad 203 . Figure 2 The gasket 203 is illustratively located between the adapter 226 and the shield 201, extending downward to the level of the base of the shield 201 and moved inward (compared to the BKM's processing accessories) to shield the gas conduction hole 249 of the shield 201, which is located on the inclined wall 244 at the bottom of the shield 201 and is relatively closer to the cover ring 212 than the BKM's processing accessories.

[0048] In a process chamber including a shielded grounding unit, the shielded grounding unit is made smaller to enable the gasket of the process kit according to the present principles to move inwardly. Figure 4 Depicts an alternative embodiment according to the present principles Figure 1 1 is a perspective view of a substrate processing chamber 100 including a process assembly 400. Figure 4 The substrate processing chamber 100 includes a processing kit 400 , a liner 203 and a shielding grounding unit 402 . Figure 4 The processing assembly 400 includes a shield 201, a cover ring 212 and a deposition ring 208. Figure 4 As shown, the shielding grounding unit 402 is located below the shielding member 201 and is implemented to ground the shielding member 201 . Figure 4 The shield ground unit 402 depicted in FIG. 4 has been reduced in size to enable the liner 203 of the process kit 400 to move inward to effectively contain the plasma. Figure 4 The dashed portion 406 of the shield ground unit 402 in FIG. 4 represents a portion of the shield ground unit 402 that has been removed to accommodate the placement of the gasket 203 relative to the shield 201 to shield the gas conduction holes 249 in the shield 201 and contain the plasma.

[0049] like Figure 4 As shown in FIG. 1 , since the size of the shielding grounding unit 402 is reduced, the shielding member 201 only slightly contacts the shielding grounding unit 402. Figure 4In the embodiment of the present invention, the inner second leg 253 of the shield 201 illustratively includes a flange 404 for contacting the shield grounding unit 402. As described above, the reduced size of the shield grounding unit 402 enables the liner 203 to move inwardly to properly shield the conductive hole 249 of the shield 201 and contain the plasma.

[0050] In some embodiments according to the present principles, when at least the spherical protrusions 272 of the cover ring 212, the angle and length of the inclined wall 244 of the shield 201, and the gas conduction holes 249 on the shield 201 are shaped and arranged relative to each other, gas conduction in the processing chamber is taken into consideration. More specifically, in a substrate processing chamber, for example Figure 1 The substrate processing chamber 100 of FIG. 100 requires a high conductance gas flow path to supply necessary process gases to the processing cavity and to properly exhaust waste process gases. In some embodiments according to the present principles, in addition to the spherical protrusions 272 of the cover ring 212, the angle and length of the inclined wall 244 of the shield 201, and the gas conduction holes 249 on the shield 201 being shaped and arranged in relation to each other to block the line of sight between the gas conduction holes 249 of the shield 201 and the gap 300 (the gap 300 is located between the target 140 and the isolator 310) and reduce the flaking of sputtered deposits, the spherical protrusions 272 of the cover ring 212, the angle and length of the inclined wall 244 of the shield 201, and the gas conduction holes 249 on the shield 201 are further shaped and arranged to attempt to maximize the gas conductance in the substrate processing chamber 100, or at least match the gas conductance of the best known method (BKM).

[0051] Figure 3A Depicted is a graph of gas flow rates for a BKM substrate processing chamber generated using computer-aided engineering (CAE) analysis. Figure 3B A substrate processing chamber (eg, Figure 1 The gas flow rate diagram of the substrate processing chamber 100 is generated using CAE analysis. Figure 3A and Figure 3B Comparison of the plots of , shows that the maximum velocity of gas conduction in the processing chamber according to the present principle is consistent with that in the BKM processing chamber. Figure 3A and Figure 3B The comparison further depicts Figure 1The gas velocity around the gas conduction holes 249 in the slanted wall 244 of the shield 201 of the substrate processing chamber 100 of the BKM substrate processing chamber is lower than the gas velocity around the gas conduction slots of the BKM substrate processing chamber. As such, there will be less particle attachment on the substrate surface in the substrate processing chamber 100 according to the present principles, at least because the lower velocity gas will cause less flaking of sputtered deposits on the surface of the processing cavity 108, and because the lower velocity gas will carry less loose sputtered particles.

[0052] In some embodiments according to the present principles, the exposed surface of at least one of the shield 201, the deposition ring 208, and the cover ring 212 is treated with a coating to improve particle retention of the film deposited on the exposed surface during substrate processing. The coating typically includes protrusions that provide micro or macro texture on the exposed surface. In one embodiment, the coating may include Lava Coat or Lava Coat II coatings, which are available from Applied Materials, Inc. in Santa Clara, California. In some embodiments, the coating may include round particles, semi-circular protrusions, and / or may include other shapes and geometries. The protrusions of the coating may include discrete protrusions that are separated from adjacent protrusions. Alternatively or additionally, the surface texturing of the coating may include a corrugated profile to improve particle adhesion. The corrugated profile of the coating may be formed via etching, bead or grit blasting, laser ablation, or 3D printing. In some embodiments, the coating may be applied to the entire exposed surface of the substrate processing chamber 100 and the processing kit 200, or alternatively may be applied to only a portion of the exposed surface of the substrate processing chamber 100 and the processing kit 200. In some other embodiments, the exposed surface of any component of the substrate processing chamber 100 is treated with the coating to improve particle retention of films deposited on the exposed surface during substrate processing as described above.

[0053] The inventors conducted mole fraction analysis testing on the process assemblies according to the principles of the present invention as described above to determine how well the process conditions of the reactive gases matched the BKM process assemblies. Although some differences were observed when looking closely at the area of ​​the process cavity, the process conditions of the reactive gases of the process assemblies according to the present principles matched well at the macroscopic level.

[0054] The process kit 200 described above significantly increases the number of process cycles and process time in the substrate processing chamber 100, thereby increasing the time between cleanings. These advantages are achieved by reducing the amount of flaking of sputtered deposits formed on components surrounding the substrate 104 and reducing the amount of sputtered deposits carried by the gas toward the gap 300 between the target 140 and the isolator 310.

[0055] Although the foregoing is directed to embodiments of the present principles, other and further embodiments may be devised without departing from the basic scope thereof. For example, it will be apparent to one of ordinary skill that the process assembly 200 or components thereof may be used in other types of applications, such as etching, CVD, and etching chambers. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments covered herein.

Claims

1. A process accessory shield, the process accessory shield being configured to surround a sputtering target, the sputtering target facing a substrate support in a substrate processing chamber, the substrate processing chamber comprising a cover ring located around the substrate support, the cover ring comprising an annular wedge, the annular wedge comprising an inclined top surface surrounding the substrate support, the inclined top surface having an inner periphery and an outer periphery and a spherical protrusion surrounding the outer periphery of the inclined top surface, the process accessory shield comprising: a cylindrical belt having a top wall and a bottom wall, the top wall being configured to surround the sputtering target and the bottom wall being configured to surround the substrate support; an inclined wall extending downwardly and radially inwardly from the bottom wall of the cylindrical band, the inclined wall having a substantially straight profile; and at least one air hole located on a lower portion of the inclined wall to allow a process gas to pass through the air hole, wherein the at least one air hole is located on the lower portion of the inclined wall so that the spherical protrusion of the cover ring blocks a line of sight between the at least one air hole on the shield and an entrance to a chamber body cavity of the substrate processing chamber when installed in the substrate processing chamber.

2. The process kit shield of claim 1, wherein the at least one air hole in the angled wall comprises a substantially rectangular shape.

3. The process kit shield of claim 1, wherein said at least one air hole in said angled wall comprises a width of about 0.2 inches to about 0.8 inches and a length of about 1 inch to about 2 inches.

4. The process kit shield of claim 1, wherein the angled wall comprises an angle of from about 15 degrees to about 45 degrees.

5. The process kit shield of claim 1, comprising at least one of a microtextured coating or a macrotextured coating on an exposed surface of the shield.

6. The process kit shield of claim 5, wherein the microtexture coating or the macrotexture coating comprises at least one of rounded particles or semi-circular protrusions.

7. A process accessory configured to be placed around a sputtering target and a substrate support in a substrate processing chamber, the process accessory comprising: A shield, the shield being configured to surround the sputtering target, the shield comprising: a cylindrical belt having a top wall and a bottom wall, the top wall being configured to surround the sputtering target and the bottom wall being configured to surround the substrate support; an inclined wall extending downwardly and radially inwardly from the bottom wall of the cylindrical band, the inclined wall having a substantially straight profile; and at least one gas hole located on a lower portion of the inclined wall to allow a process gas to pass through the gas hole; and A ring assembly, the ring assembly comprising: a cover ring configured to surround the substrate support, the cover ring comprising: an annular wedge, the annular wedge comprising an inclined top surface surrounding the substrate support, the inclined top surface having an inner periphery and an outer periphery; a spherical protrusion surrounding the outer periphery of the inclined top surface; a foot extending downwardly from the inclined top surface; a protruding edge surrounding the inner periphery of the inclined top surface; and an inner cylindrical band and an outer cylindrical band extending downwardly from the annular wedge; The at least one air hole is located on the lower portion of the inclined wall so that the spherical protrusion of the cover ring blocks the line of sight between the at least one air hole and an entrance to a chamber body cavity of the processing chamber when installed in the substrate processing chamber.

8. The process kit of claim 7, wherein the at least one air hole on the lower portion of the angled wall of the shield comprises a substantially rectangular shape.

9. The process kit of claim 7, wherein said at least one air hole on said lower portion of said sloped wall of said shield comprises a width of from about 0.2 inches to about 0.8 inches and a length of from about 1 inch to 2 inches.

10. The process kit of claim 7, wherein the angled wall of the shield comprises an angle of from about 15 degrees to about 45 degrees.

11. The process kit of claim 7, comprising at least one of a micro-textured coating or a macro-textured coating on an exposed surface of at least one of the substrate processing chamber, the shield, or the cover ring.

12. The treatment kit of claim 11, wherein the microtexture coating or the macrotexture coating comprises at least one of rounded particles or semi-circular protrusions.

13. The process kit of claim 7, wherein the ring assembly further comprises a deposition ring to support the cover ring via the footing and shield a perimeter of a substrate positioned on the substrate support.

14. The process kit of claim 7, further comprising a liner configured to surround the shield to contain plasma in a process cavity of the substrate processing chamber.

15. An apparatus for processing a substrate, comprising: A processing chamber, the processing chamber having a processing cavity and a chamber body cavity; a substrate support disposed in the processing cavity; a target material disposed in the processing cavity and opposite to the substrate support; A processing accessory, the processing accessory is located around the substrate support and the target, and the processing accessory includes: A shielding member, the shielding member surrounds the target material, and the shielding member comprises: a cylindrical belt having a top wall surrounding the target and a bottom wall surrounding the substrate support; an inclined wall extending radially inwardly from the bottom wall of the cylindrical band, the inclined wall having a substantially straight profile; and at least one gas hole, the at least one gas hole being located on a lower portion of the inclined wall to allow a process gas to pass through the gas hole; and A ring assembly, the ring assembly comprising: A cover ring, the cover ring being positioned around the substrate support, the cover ring comprising: an annular wedge comprising an inclined top surface surrounding the substrate support, the inclined top surface having an inner perimeter and an outer perimeter; a spherical protrusion surrounding said outer periphery of said inclined top surface; a footing extending downwardly from the inclined top surface, a raised edge surrounding the inner periphery of the inclined top surface; and an inner cylindrical band and an outer cylindrical band extending downwardly from said annular wedge; wherein the at least one air hole is located on the lower portion of the sloped wall such that the spherical protrusion of the cover ring blocks a line of sight between the at least one air hole on the shield and an entrance to the chamber body cavity of the processing chamber.

16. The apparatus of claim 15, wherein the at least one air hole on the shield has a width of about 0.2 inches to about 0.8 inches and a length of about 1 inch to about 2 inches, and wherein the sloped wall has an angle of about 15 degrees to about 45 degrees.

17. The apparatus of claim 15, comprising at least one of a microtextured coating or a macrotextured coating on an exposed surface of at least one of the process cavity, the shield, or the cover ring of the process chamber.

18. The apparatus of claim 17, wherein the microtextured coating or the macrotextured coating comprises at least one of rounded particles or semi-circular protrusions.

19. The apparatus of claim 17, wherein the process kit further comprises at least one of: a deposition ring that supports the cover ring via the footing and shields a perimeter of a substrate on the substrate support; or a liner that surrounds the shield to contain plasma in the process cavity of the process chamber.

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