Resonant Process Monitor

Abstract

Embodiments described herein include a resonant process monitor and a method of forming such a resonant process monitor. In one embodiment, the resonant process monitor includes a frame having a first opening and a second opening. In one embodiment, a resonant body seals the first opening of the frame. In one embodiment, a first electrode on a first surface of the resonant body contacts the frame, and a second electrode is on a second surface of the resonant body. The embodiment further includes a backplane that seals the second opening of the frame. In one embodiment, the backplane is mechanically coupled to the frame, and the inner surfaces of the resonant body, the backplane, and the frame define a cavity.

Description

Technical Field

[0001] The embodiments relate to the field of semiconductor manufacturing, and more particularly, to a resonant process monitor for real-time monitoring of chamber performance. Background Art

[0002] In semiconductor manufacturing, chamber performance needs to be closely analyzed to ensure high yield, chamber matching, process uniformity, etc. Currently, chamber performance is determined by the output obtained from the chamber (i.e., inspecting the processed substrates to determine whether the chamber is operating correctly). In addition, the chamber may be taken offline for cleaning or calibration after processing a certain number of substrates.

[0003] Semiconductor manufacturing tools may also include consumable products. For example, edge rings and process rings are typically consumable products that need to be replaced periodically. Since taking the tool offline for maintenance is expensive, it is important to know the remaining useful life of the consumable parts. Premature replacement of the consumable parts results in increased downtime. Delayed replacement of the consumable parts results in poor chamber performance. Summary of the Invention

[0004] The embodiments described herein include a resonant process monitor and a method of forming such a resonant process monitor. In one embodiment, the resonant process monitor includes a frame having a first opening and a second opening. In one embodiment, a resonant body seals the first opening of the frame. In one embodiment, a first electrode on a first surface of the resonant body contacts the frame, and a second electrode is on a second surface of the resonant body. The embodiments also include a backplane that seals the second opening of the frame. In one embodiment, the backplane is mechanically coupled to the frame, and the resonant body, the backplane, and the inner surface of the frame define a cavity.

[0005] Additional embodiments include a processing tool that includes a resonant process monitor. In one embodiment, the processing tool may include a chamber, a susceptor, and an edge ring surrounding the susceptor. In one embodiment, the resonant process monitor may be integrated in the wall of the chamber or integrated in the edge ring. In one embodiment, the resonant process monitor includes a frame having a first opening and a second opening. In one embodiment, a resonant body seals the first opening of the frame. In one embodiment, a first electrode on a first surface of the resonant body contacts the frame, and a second electrode is on a second surface of the resonant body. The embodiments also include a backplane that seals the second opening of the frame. In one embodiment, the backplane is mechanically coupled to the frame, and the resonant body, the backplane, and the inner surface of the frame define a cavity.

[0006] Additional embodiments include a method of forming a resonant process monitor. In one embodiment, the method may include contacting a first electrode on a resonant body with a frame. In one embodiment, the resonant body seals a first opening in the frame. The embodiment may then continue by contacting a first end of a contact assembly with a second electrode on the resonant body. In one embodiment, a second end of the contact assembly is supported by a backplate. Thereafter, the embodiment may include securing the backplate to the frame. In one embodiment, the backplate seals a second opening in the frame. In one embodiment, the resonant body, the backplate, and the inner sidewalls of the frame define a cavity. The embodiment may then include forming a barrier layer over at least a portion of the first electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1A is a cross-sectional view of a resonant process monitor having a barrier layer formed over the surface of a first electrode and a frame, according to one embodiment.

[0008] Figure 1B is a cross-sectional view of a frame of a resonant process monitor, according to one embodiment.

[0009] Figure 1C is a cross-sectional view of a resonant process monitor having a barrier layer formed primarily over the surface of a first electrode, according to one embodiment.

[0010] Figure 1D is a cross-sectional view of a resonant process monitor without a barrier layer, according to one embodiment.

[0011] Figure 2A is a cross-sectional view of a pedestal and an edge ring including a resonant process monitor, according to one embodiment.

[0012] Figure 2B is a plan view of a pedestal and an edge ring having multiple resonant process monitors, according to one embodiment.

[0013] Figure 3 is a schematic view of a processing tool including a resonant process monitor integrated into a sidewall of a chamber, according to one embodiment.

[0014] Figure 4 is a process flow diagram of a process for manufacturing a resonant process monitor, according to one embodiment.

[0015] Figure 5A is a cross-sectional view of a resonant body attached to a frame, according to one embodiment.

[0016] Figure 5B is a cross-sectional view of a contact assembly contacting a second electrode and a frame secured to a backplate, according to one embodiment.

[0017] Figure 5C is a cross-sectional view after forming a barrier layer over a resonant process monitor according to one embodiment.

[0018] Figure 6 shows a block diagram of an exemplary computer system that can be used in conjunction with a process that includes real-time monitoring of the etch rate of an etch process that is only radial. Detailed Description

[0019] Systems that include a resonant process monitor and the use of the resonant process monitor are described according to various embodiments. In the following description, numerous specific details are set forth to provide a thorough understanding of the embodiments. It will be apparent to those skilled in the art that the embodiments may be practiced without these specific details. In other instances, well-known aspects are not described in detail so as not to unnecessarily obscure the embodiments. Additionally, it will be understood that the various embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.

[0020] As mentioned above, chamber performance is a factor that contributes to many different process parameters. However, it is currently difficult to measure the parameters in real time. Accordingly, the embodiments described herein include a resonant process monitor for monitoring chamber performance and the life of consumable products. In some embodiments, the resonant process monitor described herein can be used to monitor chamber performance in real time.

[0021] Specifically, the embodiments described herein include a resonant process monitor that uses a resonant body. A change in the mass of the resonant body results in a change in the resonant frequency of the resonant body. As used herein, "a change in the mass of the resonant body" can refer to a change in the mass of a layer supported by the resonant body. For example, depositing a material layer over the resonant body can be referred to herein as "increasing the mass of the resonant body," and etching a material layer supported by the resonant body can be referred to as "decreasing the mass of the resonant body," although in both cases, the mass of the resonant body itself may not change.

[0022] In one embodiment, as the mass of the resonant body changes, the resonant frequency of the resonant body changes monotonically. For example, in an etch process, a decrease in the mass of the layer supported by the resonant body causes an increase in the resonant frequency of the resonant body. The increase in the resonant frequency can be measured in real time, and the rate of change of the resonant frequency is converted to the rate of change of the mass of the layer supported by the resonant body. Since the density of the film material is known, the rate of change of the mass can then be converted to the rate of change of the thickness of the layer supported by the resonant body.

[0023] Now referring to Figure 1A, a cross-sectional view of a resonant process monitor 150 is shown according to one embodiment. In one embodiment, the resonant process monitor 150 may include a frame 120. As Figure 1B shown, the frame 120 may include a first opening O1 and a second opening O2. In one embodiment, the first opening O1 and the second opening O2 of the frame 120 may have different sizes, or the sizes may be substantially similar. In the illustrated embodiment, the first opening O1 and the second opening O2 have substantially similar centerlines; however, the embodiments are not limited to this configuration. In one embodiment, the frame 120 may be any conductive material. For example, the frame 120 may include one or more of Al, Ti, W, Mo, Si, SiC, stainless steel, their alloys, or any other conductor.

[0024] Now returning to Figure 1A , in one embodiment, the first opening O1 may be sealed by a resonant body 140. In one embodiment, the first electrode 141 of the resonant body 140 may be in direct contact with the surface of the frame 120 to seal the first opening O1. In one embodiment, the first electrode 141 may be any conductive material. For example, the first electrode 141 may include one or more of Al, Ti, W, Mo, TiN, Si, SiC, Ag, Au, their alloys, or any other conductor. The second opening O2 may be sealed using a backplate 130. In one embodiment, any suitable fastener may be used to mechanically couple the backplate 130 to the frame 120. For example, the backplate 130 may be fixed to the frame 120 using screws or the like (not shown). In one embodiment, the backplate 130 may be electrically isolated from the frame 120. In one embodiment, an O-ring or other gasket 180 may be located at the junction between the frame 120 and the backplate 130. As used herein, a "sealed" opening refers to an opening that is covered, and a component that "seals" an opening refers to a component that covers the opening. It will be appreciated that "seals" may have different qualities, and the embodiments are not limited to any particular sealing quality. For example, in some embodiments described herein, a "sealed opening" may be hermetically sealed. Other embodiments may include "sealed openings" that are not hermetically sealed.

[0025] The sealed openings O1 and O2 form a cavity 110 in the resonant process monitor 150. In one embodiment, the cavity 110 may be defined by the inner surface 121 of the frame 120, the backplate 130, and the first electrode 141 of the resonant body 140. Because the cavity 110 reduces or eliminates contamination between the resonant process monitor 150 and the processing chamber, the cavity 110 is beneficial. In some embodiments, the cavity 110 may be a hermetically sealed cavity.

[0026] In one embodiment, the barrier layer 160 may be formed over the surfaces of the frame 120 and the first electrode 141. The barrier layer 160 provides additional protection against cross - contamination between the resonance process monitor 150 and the processing chamber. In one embodiment, the barrier layer 160 is an etch - resistant material. As used herein, "etch - resistant" refers to a material that resists an etch chemical more significantly than the layer on the substrate that is desired to be etched. For example, an etch - resistant material may be etched at a rate of 1:10 or greater, 1:100 or greater, 1:1000 or greater, or 1:10000 or greater. Embodiments may include any suitable material that is etch - resistant for the barrier layer 160. For example, the barrier layer 160 may include Y2O3, Al2O3, HfO2, ZrO2, La2O3, or a combination thereof; or nitrides of these oxides Y - O - N, Al - O - N, Hf - O - N, Zr - O - N, La - O - N, or a combination thereof; or fluorides of these oxides Y - O - F, Al - O - F, Hf - O - F, Zr - O - F, La - O - F, or a combination thereof; or AlN; or a stack of one or more barrier layer materials, etc. In one embodiment, the barrier layer 160 may be the same material as that used for the inner chamber wall coating. In one embodiment, the barrier layer 160 may be the same material as the edge ring in the processing chamber. In one embodiment, the barrier layer 160 may have a thickness T between about 10 nm and 200 μm.

[0027] In some embodiments, the surfaces of the first electrode 141 and the frame 120 may not be in complete direct contact (e.g., the surface roughness of the frame 120 and / or the first electrode 141 may not allow for the formation of an airtight seal between the two surfaces). In such embodiments, the barrier layer 160 improves the seal of the first opening O1. In some embodiments, the barrier layer 160 may provide an airtight seal of the first opening.

[0028] In the illustrated embodiment, the barrier layer 160 is formed over the entire upper surface of the frame 120 and over the entire surface of the first electrode 141 exposed by the first opening O1. However, it will be understood that the barrier layer 160 does not need to cover the entire surface of the frame 120. For example, Figure 1Cis a cross-sectional view, where the barrier layer 160 only covers a part of the frame 120 near the first electrode 141. In some embodiments, the barrier layer 160 may be formed over the entire exposed surface of the first electrode 141 and over the seam 148, where the frame 120 ends and the exposed surface of the first electrode 141 begins. In such an embodiment, the barrier layer 160 formed over the seam 148 may be sufficient to ensure an airtight seal of the first opening O1. In additional embodiments, the barrier layer 160 may be formed only over the first electrode 141 (i.e., the barrier layer 160 does not contact the top surface of the frame 120).

[0029] In Figure 1D yet another embodiment shown, the resonant process monitor 150 may be formed without the barrier layer 160. In such an embodiment, the surfaces of the frame 120 and the first electrode 141 may be exposed. In such an embodiment, the first electrode 141 may also serve as a barrier layer for the resonant body 140 (i.e., the first electrode 141 is the only layer covering the top surface of the resonant body 140).

[0030] Referring back Figure 1A , the resonant body 140 may be disposed between the first electrode 141 and the second electrode 142. The resonant body 140 may be a material whose resonant frequency changes as the mass of the resonant body changes. As mentioned above, "change in the mass of the resonant body" may refer to a change in the mass of a layer supported by the resonant body 140 (e.g., the barrier layer 160 or any other layer (not shown) deposited on the barrier layer 160). In one embodiment, the resonant body 140 may be a piezoelectric material. For example, the resonant body 140 may be quartz, sapphire, a semiconductor material (such as silicon, germanium, or other III-V semiconductor materials), lead zirconate titanate, etc.

[0031] In one embodiment, the first electrode 141 and the second electrode 142 can be any suitable conductive material. In one embodiment, the first electrode 141 and the second electrode 142 can include one or more of Al, Ti, W, Mo, TiN, Si, SiC, Ag, Au, their alloys, or any other conductor. In the illustrated embodiment, the second electrode 142 does not cover the entire lower surface of the resonator body 140, but it will be understood that the embodiments are not limited to this configuration. For example, in some embodiments, the second electrode 142 can cover the entire lower surface of the resonator body 140. The first electrode 141 is shown as covering the entire upper surface of the resonator body 140. However, it will be understood that in some embodiments, the first electrode 141 does not need to cover the entire upper surface of the resonator body 140. Additionally, embodiments can include a first electrode 141 and a second electrode 142 having different surface areas. For example, the second electrode 142 can have a smaller surface area compared to the first electrode 141. In yet another embodiment, the surface areas of the first electrode 141 and the second electrode 142 can be substantially the same.

[0032] In one embodiment, the contact assembly 138 can extend from the backplane 130 toward the second electrode 142 of the resonator body 140. The first end of the contact assembly 138 can directly contact the second electrode 142, and the second end of the contact assembly 138 can directly contact the backplane 130. In one embodiment, the contact assembly 138 can include any number of components that provide an electrical connection between the second electrode 142 and the backplane 130. In the illustrated embodiment, a pair of conductive pins 135 are shown as providing the electrical connection. Additional embodiments can include a contact assembly (the contact assembly includes a conductive body), a single conductive body having a plurality of protrusions, or any other electrical connection capable of applying an axial force.

[0033] In one embodiment, the backplane 130 is formed of a non-conductive material. In such an embodiment, the second end of the contact assembly 138 can contact the conductive pad 132 of the backplane 130. The conductive pad 132 can be electrically coupled to the frequency bridge 170 through conductive traces and / or wiring 133 formed into the backplane. In one embodiment, the conductive traces and / or wiring 133 can include a coaxial cable. In such an embodiment, since the coaxial cable 133 can be electrically isolated from the backplane 130, the backplane 130 can be at a ground potential 175.

[0034] In embodiments where the backplane 130 is a conductive material, the conductive pads 132 may be omitted. In such embodiments, conductive traces or wiring may electrically couple the backplane to the frequency bridge 170. In such embodiments, the backplane 130 is electrically isolated from the frame 120. In some embodiments, the gasket 180 may be sufficient to electrically isolate the frame 120 from the backplane 130. However, in additional embodiments, one or both of the frame 120 and the backplane 130 may have an insulating coating for providing electrical isolation. In one embodiment, the frame 120 electrically coupled to the first electrode 141 may be electrically coupled to the frequency bridge 170. In one embodiment, the frame 120 may be coupled to ground 175 such that the first electrode is maintained at ground potential.

[0035] It will be appreciated that maintaining electrical contact between the conductive portion of the backplane 130 and the second electrode is critical for ensuring the proper operation of the resonant process monitor 150. Accordingly, an axial force (as indicated by the arrow) may be applied by the contact assembly 138. The axial force may be sufficient to maintain contact during operation without fracturing the fragile resonant body 140. In one embodiment, the total axial force may be between approximately 0.1 N and 10.0 N. In one embodiment, the axial force may be approximately 1.0 N.

[0036] In some embodiments, the axial force applied by the contact assembly 138 may also ensure proper contact is formed between the first electrode 141 and the frame 120. For example, the axial force applied by the contact assembly 138 may be the only external force maintaining direct contact between the first electrode 141 and the frame 120. In additional embodiments, the first electrode 141 may be directly fixed to the frame by bonding. For example, some embodiments may include a first electrode diffusion bonded to the frame 120. In such embodiments, the first electrode 141 of the resonant body 140 may remain in contact with the frame 120 even if the contact assembly 138 is removed.

[0037] Now referring Figure 2A , a cross-sectional view of a pedestal 264 and an edge ring 265 including an integrated resonant process monitor 150 is shown in accordance with one embodiment. In the embodiment shown, the resonant process monitor 150 is shown as a block so as not to obscure aspects of the embodiment. However, it will be appreciated that the resonant process monitor 150 may be substantially similar to the resonant process monitor described above with respect to Figure 1A and Figure 1B .

[0038] In one embodiment, the edge ring 265 may be placed on the pedestal 264. The pedestal 264 may be any suitable pedestal used in a processing tool, such as a semiconductor processing tool, etc. The pedestal is schematically shown, and it will be understood that additional components may be integrated into the pedestal as known in the art. The substrate 262 may be supported by the pedestal 264. The substrate 262 may be any substrate being processed in the processing tool, such as a semiconductor substrate, a sapphire substrate, a glass substrate, etc. In one embodiment, the edge ring 265 may surround the perimeter of the substrate 262.

[0039] In one embodiment, the resonant process monitor 150 may be integrated into the edge ring 265. The resonant process monitor 150 may be positioned near the inner edge of the edge ring 265. In a specific embodiment, the edge of the process monitor 150 may be spaced apart from the edge of the substrate 162 by a distance D. In one embodiment, the distance D may be less than 300 mm. In one embodiment, the distance D may be less than 100 mm. In one embodiment, the distance D may be less than 10 mm.

[0040] In one embodiment, the resonant process monitor 150 may be electrically coupled through the pedestal 264 and out of the process chamber (not shown) by one or more wires 251A. It will be understood that the one or more wires 251 may include many different exit paths from the chamber. For example, the wire 251 A is formed entirely within the pedestal 264. In different embodiments, at least a portion of the length of the wire 251 B may be formed outside the pedestal 264. In yet another embodiment, as shown by the wire 251 C the wire may exit the chamber by passing through a wall. Thus, data from the process monitor 150 may be obtained in real time to provide an "in-situ" analysis of the chamber performance.

[0041] Specifically, integrating the resonant process monitor 150 into the edge ring 265 allows for monitoring the condition of the edge ring. For example, a sacrificial layer (not shown) may be formed over a barrier layer having the same material as the edge ring. The thickness change of the sacrificial layer during processing may be monitored in real time by the resonant process monitor 150. Thus, it may be determined based on the information from the resonant process monitor 150 when the edge ring 265 needs to be replaced (e.g., when it is corroded below a certain threshold and needs to be replaced).

[0042] Now referring to Figure 2B in accordance with one embodiment, there is shown Figure 2AA plan view of the system in. In the illustrated embodiment, four resonant process monitors 150 are integrated into the edge ring 265. However, it will be understood that any number of resonant process monitors 150 (e.g., one or more resonant process monitors 150) can be integrated into the edge ring 265.

[0043] Now refer to Figure 3 , a cross-sectional view of a processing tool 300 with integrated resonant process monitors 150 is shown according to one embodiment. In one embodiment, one or more processing gases can flow through the gas ports / vents 303 / 304 into the chamber 307. The processing gas can be ionized using a power source (e.g., a radio frequency source or a microwave frequency source), which is coupled to the applicator 302 to form a plasma 306. In one embodiment, the applicator 302 can be a component of the cover 388 of the chamber. The plasma 306 can interact with the surface of the substrate 262 located on the pedestal 264. In one embodiment, the edge ring 265 can surround the substrate 262. Although not shown in Figure 3 , it will be understood that the tool 300 can include resonant process monitors 150 integrated into the edge ring 265 (similar to the edge ring described in Figure 2A ). It will be understood that the processing tool 300 shown in Figure 3 is exemplary in nature and is highly simplified by removing components known to those of ordinary skill in the art (e.g., vacuum pumps, heating elements, electrical components, etc.) so as not to obscure aspects of the various embodiments.

[0044] In one embodiment, the resonant process monitor 150 can be oriented such that the face of the first electrode faces outward from the wall 308 of the chamber 300. As used herein, the wall 308 of the chamber 300 can refer to the sidewall, the surface of the cover 388, and the surface of the applicator 302. For example, the resonant process monitor 150 A can be positioned along the sidewall 308 of the chamber 300, the resonant process monitor 150 B can be positioned along the cover wall 308 of the chamber 300, or the resonant process monitor 150 C can be positioned along the applicator wall 308 of the processing chamber 300. In one embodiment, the resonant process monitor 150 forms a part of the wall 308 of the chamber 300. For example, the frame 120 and / or the backplane 130 can form a part of the wall 308 of the chamber 300. In one embodiment, the barrier layer 160 of the resonant process monitor 150 can be the same material as the material used for coating the inner wall 308 of the chamber 300. Thus, changes in the inner surface coating can be monitored in real time.

[0045] Now refer to Figure 4 and Figures 5A to 5C, A process flow diagram of process 490 for manufacturing the resonant process monitor 150 is shown according to one embodiment. Now referring to operation 491, as Figure 5A shown, process 490 may include bringing a first electrode on the resonant body 140 into contact with the frame 120. In one embodiment, the first electrode 141 of the resonant body seals the first opening O1 in the frame 120. In one embodiment, the first electrode 141 may be joined to the frame 120. For example, the first electrode 141 may be diffusion-joined to the frame 120. In some embodiments, the first electrode 141 may hermetically seal the first opening O1.

[0046] Now referring to operation 492, as Figure 5B shown, process 490 may include bringing a first end of the contact assembly 138 into contact with a second electrode 142 on the resonant body 140. In one embodiment, a second end of the contact assembly 138 is supported by the backplane 130. In one embodiment, as indicated by the arrow, the contact assembly may apply an axial force to the resonant body 140. For example, the axial force may be between approximately 0.1 N and 10.0 N.

[0047] Now referring to operation 493, process 490 may include fixing the backplane 130 to the frame 120. In one embodiment, the frame 120 may be fixed to the backplane 130 using fasteners (not shown) such as screws. In one embodiment, the backplane 130 seals the second opening O2 in the frame 120. In one embodiment, a gasket or O-ring may separate the backplane 130 from the frame 120. In one embodiment, the frame 120 and the backplane 130 are electrically isolated. In one embodiment, the cavity 110 is defined by the first electrode 141, the backplane 130, and the inner surface 121 of the frame 120. In one embodiment, the cavity 110 is a hermetically sealed cavity.

[0048] Now referring to operation 494, as Figure 5CAs shown, the process 490 may include forming a barrier layer 160 over at least a portion of the first electrode 141. In one embodiment, the barrier layer 160 is formed over the surface of the first electrode 141 and the frame 120. In one embodiment, the barrier layer 160 hermetically seals the first opening O1. In one embodiment, the barrier layer 160 is an etch-resistant material. For example, the barrier layer 160 may include Y2O3, Al2O3, HfO2, ZrO2, La2O3, or a combination thereof; or nitrides of these oxides Y-O-N, Al-O-N, Hf-O-N, Zr-O-N, La-O-N, or a combination thereof; or fluorides of these oxides Y-O-F, Al-O-F, Hf-O-F, Zr-O-F, La-O-F, or a combination thereof; or AlN; or a stack of one or more barrier layer materials, etc. In one embodiment, the barrier layer 160 is formed using any suitable deposition process, such as sputtering, ALD, plasma-enhanced ALD (PEALD), CVD, plasma-enhanced CVD (PECVD), evaporation, sputtering, plasma arc coating, aerosol coating, or a combination of more than one process. In one embodiment, the barrier layer 160 may be between about 10 nm and 200 μm. In one embodiment, the deposition process is performed at a temperature less than 200 °C. In one embodiment, the deposition process is performed at a temperature less than 150 °C.

[0049] Now referring Figure 6 , a block diagram of an exemplary computer system 660 of a processing tool is shown in accordance with one embodiment. In one embodiment, the computer system 660 is coupled to the processing tool and controls the processing in the processing tool. The computer system 660 may be connected (e.g., network-connected) to other machines in a local area network (LAN), intranet, extranet, or the Internet. The computer system 660 may operate in the capacity of a server or client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The computer system 660 may be a personal computer (PC), tablet PC, set-top box (STB), personal digital assistant (PDA), cellular phone, network device, server, network router, switch, or bridge, or any machine capable of (continuously or otherwise) executing a set of instructions that specify actions to be taken by the machine. Additionally, although only a single machine is shown for the computer system 660, the term "machine" should also be considered to include any collection of machines (e.g., computers) that individually or jointly execute a set of instructions (or multiple sets of instructions) to perform any one or more of the methods described herein.

[0050] The computer system 660 may include a computer program product or software 622 having a non-transitory machine-readable medium with instructions stored thereon, and the computer program product or software may be used to program the computer system 660 (or other electronic devices) to perform the processes according to the embodiments. The machine-readable medium includes any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer). For example, the machine-readable (e.g., computer-readable) medium includes machine (e.g., computer) readable storage media (e.g., read-only memory (“ROM”), random access memory (“RAM”), magnetic disk storage media, optical storage media, flash memory devices, etc.), machine (e.g., computer) readable transmission media (electrical signals, optical signals, acoustic signals, or other forms of propagated signals (e.g., infrared signals, digital signals, etc.)), etc.

[0051] In one embodiment, the computer system 660 includes a system processor 602, a main memory 604 (e.g., read-only memory (ROM), flash memory, dynamic random access memory (DRAM) (such as synchronous DRAM (SDRAM) or memory bus DRAM (RDRAM), etc.), a static memory 606 (e.g., flash memory, static random access memory (SRAM), etc.), and an auxiliary memory 618 (e.g., a data storage device) that communicate with each other via a bus 630.

[0052] The system processor 602 represents one or more general-purpose processing devices, such as a microprocessor, a central processing unit, etc. More specifically, the system processor may be a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a system processor implementing other instruction sets, or a system processor implementing a combination of instruction sets. The system processor 602 may also be one or more dedicated processing devices, such as an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a digital signal system processor (DSP), a network system processor, etc. The system processor 602 is configured to execute a processing logic unit 626 for performing the operations described herein.

[0053] The computer system 660 may further include a system network interface device 608 for communicating with other devices or machines. The computer system 660 may also include a video display unit 610 (e.g., a liquid crystal display (LCD), a light emitting diode display (LED), or a cathode ray tube (CRT)), an alphanumeric input device 612 (e.g., a keyboard), a cursor control device 614 (e.g., a mouse), and a signal generation device 616 (e.g., a speaker).

[0054] The auxiliary storage 618 may include a machine-accessible storage medium 631 (or more specifically, a computer-readable storage medium) on which one or more instruction sets (e.g., software 622) are stored, the instruction sets embodying any one or more of the methods or functions described herein. The software 622 may also reside, completely or at least partially, within the main memory 604 and / or within the system processor 602 during execution by the computer system 660, the main memory 604 and the system processor 602 also constituting a machine-readable storage medium. The software 622 may further be transmitted or received over the network 620 via the system network interface device 608.

[0055] Although the machine-accessible storage medium 631 is shown as a single medium in the exemplary embodiment, the term "machine-readable storage medium" should be considered to include a single medium or multiple media (e.g., a centralized or distributed database, and / or associated caches and servers) that store one or more instruction sets. The term "machine-readable storage medium" should also be considered to include any medium that is capable of storing or encoding instruction sets for execution by a machine and that causes the machine to perform any one or more of the methods. The term "machine-readable storage medium" should thus be considered to include, but not be limited to, solid-state memory, as well as optical and magnetic media.

[0056] In the foregoing description, specific exemplary embodiments have been described. Obviously, various modifications can be made thereto without departing from the scope of the following claims. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.

Claims

1. A resonant process monitor, comprising: A frame, wherein the frame includes a first opening and a second opening; A resonant body that seals the first opening of the frame, wherein a first electrode on a first surface of the resonant body contacts the frame, and wherein a second electrode is on a second surface of the resonant body, and wherein only the second electrode contacts the second surface of the resonant body; And A backplane that seals the second opening of the frame, wherein the backplane is mechanically coupled to the frame, wherein the resonant body, the backplane, and an inner surface of the frame define an airtight sealed cavity, and wherein the second electrode and a portion of the second surface of the resonant body and a side surface of the resonant body are exposed to the airtight sealed cavity.

2. The resonant process monitor according to claim 1, further comprising a barrier layer on at least a portion of the first electrode, and wherein the barrier layer is an etch-resistant coating.

3. The resonant process monitor according to claim 2, wherein the barrier layer comprises one or more of the following: Y2O3, Al2O3, HfO2, ZrO2, La2O3, or a combination thereof; or nitrides of Y-O-N, Al-O-N, Hf-O-N, Zr-O-N, La-O-N, or a combination thereof; or fluorides of Y-O-F, Al-O-F, Hf-O-F, Zr-O-F, La-O-F, or a combination thereof; or AlN; or a stack of one or more barrier layer materials.

4. The resonant process monitor according to claim 2, wherein the barrier layer covers the entire portion of the first electrode visible through the first opening of the frame.

5. The resonant process monitor according to claim 4, wherein the barrier layer is formed on a portion of the frame.

6. The resonant process monitor according to claim 1, further comprising: A contact assembly that extends from the backplane to the second electrode, wherein an axial force along the contact assembly is applied to the second electrode.

7. The resonant process monitor according to claim 6, wherein the axial force is less than 10 N.

8. The resonant process monitor according to claim 6, wherein the axial force fixes the first electrode against the frame.

9. The resonant process monitor according to claim 1, wherein the first electrode is diffusion bonded to the frame.

10. The resonant process monitor according to claim 2, wherein the barrier layer has a thickness of less than 200 μm.

11. The resonant process monitor according to claim 1, wherein the resonant body is one of quartz, sapphire, silicon, germanium, or lead zirconate titanate.

12. The resonant process monitor according to claim 1, further comprising: A frequency bridge electrically coupled between the first electrode and the second electrode, and wherein the first electrode is electrically coupled to a ground potential.

13. A processing tool, comprising: A chamber; A susceptor; An edge ring that surrounds the susceptor; And A resonant process monitor, the resonant process monitor being integrated into the edge ring or the wall of the chamber and comprising: A frame, wherein the frame includes a first opening and a second opening; A resonant body, the resonant body sealing the first opening of the frame, wherein a first electrode on a first surface of the resonant body contacts the frame, and wherein a second electrode is on a second surface of the resonant body, and wherein only the second electrode contacts the second surface of the resonant body; and A backplate, the backplate sealing the second opening of the frame, wherein the backplate is mechanically coupled to the frame, wherein the resonant body, the backplate, and the inner surface of the frame define an airtight cavity, and wherein the second electrode and a portion of the second surface of the resonant body and the side surface of the resonant body are exposed to the airtight cavity.

14. The processing tool of claim 13, wherein the resonant process monitor further comprises a barrier layer on at least a portion of the first electrode.

15. A method of forming a resonant process monitor, comprising: Contacting a first electrode on a resonant body with a frame, wherein the resonant body seals a first opening in the frame; Contacting a first end of a contact assembly with a second electrode on the resonant body, wherein only the second electrode contacts a second surface of the resonant body, and wherein a second end of the contact assembly is supported by a backplate; Securing the backplate to the frame, wherein the backplate seals a second opening in the frame, and wherein the resonant body, the backplate, and the inner sidewall of the frame define an airtight cavity, and wherein the second electrode and a portion of the second surface of the resonant body and the side surface of the resonant body are exposed to the airtight cavity; and Forming a barrier layer over at least a portion of the first electrode.

16. The method of claim 15, further comprising: Bonding the first electrode to the frame.

17. The method of claim 15, wherein the barrier layer is formed by: sputtering, ALD, plasma-enhanced ALD (PEALD), CVD, plasma-enhanced CVD (PECVD), evaporation, sputtering, plasma arc coating, aerosol coating, or a combination of more than one process.

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