Method and apparatus for passivating a target material

Abstract

Methods and apparatus for passivating a target are provided herein. For example, a method includes: a) supplying an oxidizing gas into an interior space of a processing chamber; b) igniting the oxidizing gas to form a plasma and oxidize a target or at least one of the target materials, the target material being deposited on a processing accessory disposed in the interior space of the processing chamber; and c) performing a cyclic purge, including: c1) supplying air into the processing chamber to react with at least one of the target material or the target material deposited on the processing accessory; c2) maintaining a predetermined pressure in the processing chamber for a predetermined time to produce toxic byproducts caused by the reaction of the air with at least one of the target material or the target material deposited on the processing accessory; and c3) evacuating the processing chamber to remove the toxic byproducts.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to methods and apparatus for passivating a target material. Background Art

[0002] Processing chambers, such as physical vapor deposition (PVD) chambers, are often used for ovonic threshold switch (OTS) manufacturing. OTS include various types of compounds that exhibit certain electrical behaviors, making OTS suitable for (but not limited to) forming critical layers (e.g., selectors) in memory products (e.g., PCRAM, ReRAM, etc.). Compounds (e.g., compounds that make up target materials) can have different elements with different atomic weight percentages, but almost always have arsenic (As), making the compounds highly toxic and active. For example, if the target material is not fully passivated, the target material containing As can be highly active and can react with, for example, room air and produce toxic byproducts such as hydrides and arsine. In view of this, caution is required when performing preventive maintenance (PM) on a processing chamber that was previously used for OTS manufacturing (e.g., containing an OTS target). For example, PM typically requires passivation of the OTS target and / or hydride monitoring to ensure that PM can be performed in a safe manner.

[0003] Current state-of-the-art passivation techniques are often very inefficient and may last more than five days. In addition, such passivation techniques may expose the process chamber cavity (eg, the chamber in which the OTS target is disposed) to the environment, which in turn may be hazardous to personnel.

[0004] Therefore, the inventors provide improved methods and apparatus for passivating OTS targets. Summary of the invention

[0005] Methods and apparatus for passivating a target are provided herein. In some embodiments, a method includes: a) supplying an oxidizing gas into an interior space of a processing chamber; b) igniting the oxidizing gas to form a plasma and oxidize a target or at least one of a target material, the target material being deposited on a processing accessory disposed in the interior space of the processing chamber; and c) performing a cyclic purge, including: c1) supplying air to the processing chamber to react with at least one of the target material or the target material deposited on the processing accessory; c2) maintaining a predetermined pressure in the processing chamber for a predetermined time to produce toxic byproducts caused by the reaction of the air with at least one of the target material or the target material deposited on the processing accessory; and c3) evacuating the processing chamber to remove the toxic byproducts.

[0006] According to at least some embodiments, a non-transitory computer-readable storage medium having instructions stored thereon, which when executed by a processor, performs a method for passivating a surface in a processing chamber, the method comprising: a) supplying an oxidizing gas into an interior space of the processing chamber; b) igniting the oxidizing gas to form a plasma and oxidize a target material or at least one of the target materials deposited on a processing accessory disposed in the interior space of the processing chamber; and c) performing a cyclic purge, including: c1) providing air to the processing chamber to react with at least one of the target material or the target material deposited on the processing accessory; c2) maintaining a predetermined pressure in the processing chamber for a predetermined time to produce toxic byproducts caused by the reaction of the air with the target material or at least one of the target materials deposited on the processing accessory; and c3) evacuating the processing chamber to remove the toxic byproducts.

[0007] According to at least some embodiments, a processing chamber for passivating a surface of a processing chamber includes: a target material, the target material is disposed in the processing chamber, and is used to sputter the target material onto a substrate disposed in the processing chamber during processing; a gas source, the gas source is connected to the processing chamber and is configured to supply an oxidizing gas into an interior space of the processing chamber, and is configured to supply air into the interior space of the processing chamber without opening the processing chamber; at least one of an RF power source or a DC power source, the at least one of the RF power source or the DC power source is configured to ignite the oxidizing gas to form a plasma in the processing chamber; a pump, the pump is configured to maintain a predetermined pressure and exhaust the processing chamber; a gas detection system, the gas detection system is configured to measure The amount of toxic byproducts in the interior space of the processing chamber; and a controller, the controller being configured to control the processing chamber to: a) supply an oxidizing gas from a gas source to the interior space of the processing chamber; b) ignite the oxidizing gas to form a plasma and oxidize a target material or at least one of the target materials, the target material being deposited on a processing accessory disposed in the interior space of the processing chamber; and c) perform a cyclic purge, including: c1) supplying air to the processing chamber to react with at least one of the target material or the target material deposited on the processing accessory; c2) maintaining a predetermined pressure in the processing chamber for a predetermined time to produce toxic byproducts caused by the reaction of the air with at least one of the target material or the target material deposited on the processing accessory; and c3) evacuating the processing chamber to remove the toxic byproducts.

[0008] Other and further embodiments of the present disclosure are described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Embodiments of the present disclosure, briefly summarized above and discussed in more detail below, may be understood by reference to the illustrative embodiments of the present disclosure depicted in the accompanying drawings. However, the drawings illustrate only typical embodiments of the present disclosure and therefore should not be considered limiting the scope of the present disclosure, as the disclosure may admit to other equally effective embodiments.

[0010] Figure 1 Depicted is a schematic cross-sectional view of a physical vapor deposition chamber (PVD) according to some embodiments of the present disclosure.

[0011] Figure 2 is a flow chart of a method of passivating a target in a processing chamber according to some embodiments of the present disclosure.

[0012] To aid understanding, the same reference numerals have been used as much as possible to designate 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 beneficially incorporated into other embodiments without further description. DETAILED DESCRIPTION

[0013] Embodiments of methods and apparatus for passivating a target are provided herein. For example, in at least some embodiments, the methods and apparatus described herein can be used to passivate a target (e.g., during PM), such as an OTS target material. More specifically, the methods and apparatus described herein can be used to passivate and stabilize the surface of a target to prevent further reaction of the target with one or more gases (e.g., air) sometimes used in a passivation process. Unlike conventional methods and apparatus that can be used to passivate a target, the methods and apparatus described herein use an oxygen plasma treatment to passivate the OTS target, which, combined with cyclic purges that do not require exposing the interior space of the processing chamber to the ambient environment, produces a better passivation / oxidation surface of the OTS target. Therefore, the methods and apparatus described herein provide a more efficient process for passivating a target, thereby significantly reducing the total passivation time, for example, the total passivation time can be reduced from greater than 5 days to less than 30 hours.

[0014] Figure 1 A schematic cross-sectional view of a PVD chamber (processing chamber 100) according to some embodiments of the present disclosure is depicted. Examples of suitable PVD chambers include and SIP PVD processing chambers, both of which are commercially available from Applied Materials, Inc. of Santa Clara, Calif. Other processing chambers from Applied Materials or other manufacturers may also benefit from the inventive apparatus disclosed herein.

[0015] The processing chamber 100 includes a substrate support pedestal 102 for receiving a substrate 104 thereon, and a sputtering source, such as a target 106. The substrate support pedestal 102 may be located within a grounded chamber wall 108, which may be a chamber wall (as shown) or a grounded shield. Figure 1 , a grounded shield 140 is shown covering at least some portion of the processing chamber 100 above the target 106. In some embodiments, the grounded shield 140 can extend below the target to surround the pedestal 102 as well.

[0016] The processing chamber 100 includes a feeding structure 110 for coupling RF and DC energy to the target 106. The feeding structure is a device for coupling RF energy (and optionally DC energy) to the target 106 (or an assembly including a target, such as described herein). The feeding structure 110 includes a body 112 having a first end 114 and a second end 116 opposite the first end 114. In some embodiments, the body 112 further includes a central opening 115 disposed through the body 112 from the first end 114 to the second end 116.

[0017] The first end 114 of the feeding structure 110 can be coupled to an RF power source 118 and an optional DC power source 120, which can be used to provide RF and DC energy to the target 106, respectively. For example, the DC power source 120 can be used to apply a negative voltage or bias to the target 106. In some embodiments, the frequency range of the RF energy supplied by the RF power source 118 can be from about 2 MHz to about 60 MHz, or non-limiting frequencies such as 2 MHz, 13.56 MHz, 27.12 MHz, or 60 MHz can be used, for example. In some embodiments, multiple RF power sources (i.e., two or more) can be provided to provide RF energy at multiple of the above frequencies. In at least some embodiments, during passivation and / or PVD of the target 106, one or both of the RF power source 118 or the DC power source 120 can be used to ignite one or more process gases. The feeding structure 110 can be made of a suitable conductive material to conduct the RF and DC energy from the RF power source 118 and the DC power source 120. The feed structure 110 may have a suitable length that facilitates substantially uniform distribution of the respective RF and DC energies around the perimeter of the feed structure 110 .

[0018] The second end 116 of the body 112 is coupled to a source distribution plate 122. The source distribution plate includes an aperture 124 disposed through the source distribution plate 122 and aligned with the central opening 115 of the body 112. The source distribution plate 122 may be made of a suitable conductive material to conduct RF and DC energy from the feed structure 110.

[0019] The source distribution plate 122 may be coupled to the target 106 via a conductive member 125. The conductive member 125 may be a tubular member having a first end 126 coupled to a target-facing surface 128 of the source distribution plate 122 proximate a peripheral edge of the source distribution plate 122. The conductive member 125 further includes a second end 130 coupled to a source distribution plate-facing surface 132 of the target 106 (or to a backing plate 146 of the target 106) proximate a peripheral edge of the target 106.

[0020] The cavity 134 can be defined by the inwardly facing walls of the conductive member 125, the target-facing surface 128 of the source distribution plate 122, and the source distribution plate-facing surface 132 of the target 106. The cavity 134 is fluidly coupled to the central opening 115 of the body 112 via the holes 124 of the source distribution plate 122. The cavity 134 and the central opening 115 of the body 112 can be used to at least partially accommodate a Figure 1 One or more portions of a rotatable magnetron assembly 136 shown and described further below. In some embodiments, the cavity can be at least partially filled with a cooling fluid such as water (H2O) or the like.

[0021] A ground shield 140 may be provided to cover the outer surface of the lid of the processing chamber 100. The ground shield 140 may be grounded, for example, via a ground connection of the chamber body. The ground shield 140 has a central opening to allow the feed structure 110 to pass through the ground shield 140 to couple to the source distribution plate 122. The ground shield 140 may include any suitable conductive material, such as aluminum, copper, or the like. An insulating gap 139 is provided between the ground shield 140 and the outer surface of the source distribution plate 122, the conductive member 125, and the target material 106 (and / or the backing plate 146) to prevent RF and DC energy from being directed directly to ground. The insulating gap may be filled with air or some other suitable dielectric material, such as ceramic, plastic, or the like.

[0022] In some embodiments, a grounding collar 141 may be disposed around the lower portion of the feed structure 110 and the body 112. The grounding collar 141 is coupled to the ground shield 140 and may be an integral part of the ground shield 140, or may be a separate part coupled to the ground shield to provide grounding of the feed structure 110. The grounding collar 141 may be made of a suitable conductive material such as aluminum or copper, and the gap may be filled with an insulating material such as plastic or ceramic, or may be an air gap. The grounding collar 141 prevents crosstalk between the RF feed and the body 112, thereby improving plasma and process uniformity.

[0023] An isolation plate 138 may be disposed between the source distribution plate 122 and the ground shield 140 to prevent RF and DC energy from being directed directly to ground. The isolation plate 138 has a central opening to allow the feed structure 110 to pass through the isolation plate 138 and couple to the source distribution plate 122. The isolation plate 138 may include a suitable dielectric material, such as ceramic, plastic, or the like.

[0024] The target 106 may be supported on an adapter 142 by a dielectric isolator 144, which may be a grounded conductive aluminum adapter. The target 106 includes a material to be deposited on the substrate 104 during sputtering, such as a metal or a metal oxide. For example, in some embodiments, such as when the target 106 is used for OTS manufacturing, the target 106 may be made of at least one of arsenic, boron, carbon, gallium, germanium, selenium, silicon, tellurium, titanium, or tungsten. In some embodiments, a backing plate 146 may be coupled to a surface 132 of the target 106 that faces the source distribution plate. The backing plate 146 may include a conductive material, such as copper zinc, copper chromium, or the same material as the target, so that RF and DC power can be coupled to the target 106 via the backing plate 146. Alternatively, the backing plate 146 may be non-conductive and may include a conductive element (not shown), such as an electrical feed-through structure or the like for coupling the surface 132 of the target 106 that faces the source distribution plate to the second end 130 of the conductive member 125. A backing plate 146 can be included, for example, to improve the structural stability of the target 106. In at least some embodiments, one or more cooling channels / guides 147 can be provided in the backing plate 146 to facilitate cooling the target 106, for example, while performing a passivation process.

[0025] The substrate support pedestal 102 has a material receiving surface facing the major surface of the target 106 and supports the substrate 104 to be sputter-coated in a planar position relative to the major surface of the target 106. The substrate support pedestal 102 can support the substrate 104 in an interior space 148 of the processing chamber 100. The interior space 148 is defined as the area above the substrate support pedestal 102 during processing (e.g., between the target 106 and the substrate support pedestal 102 when in a processing position).

[0026] In some embodiments, the substrate support pedestal 102 may be vertically movable via a bellows 150 connected to a bottom chamber wall 152 to allow a substrate 104 to be transferred onto the substrate support pedestal 102 through a load lock valve (not shown) in a lower portion of the processing chamber 100 and then raised to a deposition position or a processing position.

[0027] One or more process gases (e.g., room air, oxygen, non-reactive gases (including argon, helium, krypton, neon, radon, xenon), or other gases suitable for processing the substrate 104 and / or performing a passivation process on the target material 106) can be supplied from a gas source 154 to the lower portion of the processing chamber 100 through a mass flow controller 156. The gas source 154 can also be used to vent fresh (room) air into the interior space 148 of the processing chamber 100, such as when performing passivation of the target material 106, which will be described in more detail below. The mass flow controller 156 controls the gas flow from the gas source 154 using, for example, a control feedback loop, which will also be described in more detail below.

[0028] An exhaust port 158 ​​may be provided and coupled to a pump 161 via a valve 160 for exhausting (e.g., evacuating) the interior volume 148 of the processing chamber 100 and helping to maintain a desired pressure within the processing chamber 100. For example, the valve 160 may be configured to provide a relatively higher pressure during passivation and a relatively lower pressure during PVD.

[0029] The gas detection system 163 can be coupled to the processing chamber 100 and can be configured to detect gases exhausted from the interior space 148. For example, in at least some embodiments, the gas detection system 163 can be configured for gas detection, and when the processing chamber 100 is being used to passivate the target 106 (e.g., during PM), the gas detection system 163 can be configured to detect toxic byproducts exhausted from the interior space 148. An example of a gas detection system suitable for use in the methods and apparatus described herein is the SPM available from Honeywell Analytics, Inc., Lincolnshire, IL, USA. Toxic byproducts may include, but are not limited to, hydrides, arsine, inorganic acids, amines, and / or other toxic byproducts. The gas detection system 163 measures the amount of toxic byproducts exhausted from the interior space 148 of the processing chamber 100, and transmits the measured amount to the controller 191 of the processing chamber 100, which in turn compares the measured amount with a predetermined threshold. The predetermined threshold may be determined based on the type of toxic byproduct being detected / measured. For example, when the toxic byproduct is a hydride and / or arsine, the predetermined threshold may be from about 0 ppb to about 100 ppb, and in some embodiments may be about 5 ppm.

[0030] Additionally, one or more sensors 165 may be connected to the gas detection system 163 (see dashed line 167 ) and disposed, for example, near the valve 160 , to obtain data that may be used to control the mass flow controller 156 , as described in more detail below.

[0031] An RF bias power source 162 may be coupled to the substrate support pedestal 102 to induce a negative DC bias on the substrate 104. Additionally, in some embodiments, a negative DC self-bias may be formed on the substrate 104 during processing. For example, the frequency of the RF power supplied by the RF bias power source 162 may range from about 2 MHz to about 60 MHz, for example, non-limiting frequencies such as 2 MHz, 13.56 MHz, or 60 MHz may be used. In other applications, the substrate support pedestal 102 may be grounded or electrically floating. For example, for applications where RF bias power may not be required, a capacitive tuner 164 may be coupled to the substrate support pedestal to adjust the voltage on the substrate 104.

[0032] The rotatable magnetron assembly 136 can be positioned proximate to the rear surface of the target 106 (e.g., the surface 132 facing the source distribution plate). The rotatable magnetron assembly 136 includes a plurality of magnets 166 supported by a base plate 168. The base plate 168 is connected to a rotation shaft 170 that coincides with the central axis of the processing chamber 100 and the substrate 104. A motor 172 can be coupled to the upper end of the rotation shaft 170 to drive the rotation of the rotatable magnetron assembly 136. The magnets 166 generate a magnetic field within the processing chamber 100 that is generally parallel to and proximate to the surface of the target 106 to capture electrons and increase the local plasma density, which in turn increases the sputtering rate. The magnets 166 generate an electromagnetic field around the top of the processing chamber 100, and the magnets 166 rotate to rotate the electromagnetic field, which affects the plasma density of the process to more uniformly sputter the target 106.

[0033] In some embodiments, magnets 190 may be disposed around the processing chamber 100 to selectively provide a magnetic field between the substrate support pedestal 102 and the target 106. For example, Figure 1 As shown, the magnet 190 can be disposed around the exterior of the chamber wall 108, in an area just above the substrate support pedestal 102 when in the processing position. In some embodiments, the magnet 190 can additionally or alternatively be disposed in other locations, such as adjacent to the adapter 142. The magnet 190 can be an electromagnet, and can be coupled to a power source (not shown) to control the magnitude of the magnetic field generated by the electromagnet.

[0034] In some embodiments, the processing chamber 100 may further include a processing accessory 143, which includes a grounded bottom shield 174 connected to a ledge 176 of the adapter 142. The processing accessory 143 also includes a dark space shield 178, which can be supported on the bottom shield 174 and can be fastened to the bottom shield 174 by screws or other suitable means. The metal threaded connection between the bottom shield 174 and the dark space shield 178 allows the bottom shield 174 and the dark space shield 178 to be grounded to the adapter 142. The adapter 142 is in turn sealed and grounded to the chamber wall 108. The bottom shield 174 and the dark space shield 178 are typically formed of hard, non-magnetic stainless steel. In at least some embodiments, the dark space shield 178 and the bottom shield 174 can be integrally formed and configured as a whole.

[0035] The bottom shield 174 extends downwardly and may include a generally tubular portion 180 having a generally constant or varying diameter. The bottom shield 174 extends downwardly along the chamber wall 108 and the wall of the adapter 142 to below the top surface of the substrate support pedestal 102 and returns upwardly until it reaches the top surface of the substrate support pedestal 102 (e.g., forming a U-shaped portion 184 at the bottom). A cover ring 186 is seated on top of an upwardly extending inner portion 188 of the bottom shield 174 when the substrate support pedestal 102 is in the lower loading position, but is seated on the periphery of the substrate support pedestal 102 when the substrate support pedestal 102 is in the upper deposition position to protect the substrate support pedestal 102 from sputter deposition.

[0036] The controller 191 includes a programmable central processing unit (CPU) 192 (processor) that can operate with a memory 194 and a mass storage device, an input control unit, and a display unit (not shown), such as a power supply, a clock, a cache, an input / output (I / O) circuit, and pads, which are coupled to various components of the processing system to assist in controlling substrate processing.

[0037] To assist in controlling the processing chamber 100 described above, the CPU 192 may be any form of general purpose computer processor that can be used in an industrial setting, such as a programmable logic controller (PLC) to control the various chambers and subprocessors. A memory 194 is coupled to the CPU 192 and is a non-transitory computer readable storage medium and may be one or more readily accessible memories such as a random access memory (RAM), a read only memory (ROM), a disk drive, a hard disk, or any other form of digital storage located locally or remotely. Support circuits 196 are coupled to the CPU 192 to support the processor in a conventional manner. Charged species generation, heating, and other processes are generally stored in the memory 194, usually as a software program. The software program may also be stored and / or executed by a second CPU (not shown) that is located remotely from the processing chamber 100 controlled by the CPU 192.

[0038] The memory 194 is in the form of a computer-readable storage medium that contains instructions that, when executed by the CPU 192, assist in the operation of the processing chamber 100. The instructions in the memory 194 are in the form of a program product, such as a program that implements the method of the present disclosure. The program code may conform to any of a number of different programming languages. In one example, the present disclosure may be implemented as a program product stored on a computer-readable storage medium for use with a computer system. The program of the program product defines the functions of the implementation (including the method described herein). Illustrative computer-readable storage media include (but are not limited to): (i) non-writable storage media (e.g., a read-only memory device within a computer, such as a CD-ROM disk that can be read by a CD-ROM drive, a flash memory, a ROM chip, or any type of solid-state non-volatile semiconductor memory), on which information is permanently stored; and (ii) writable storage media (e.g., a disk within a disk drive or hard drive or any type of solid-state random access semiconductor memory), on which changeable information is stored. Such non-transitory computer-readable storage media, when loaded with computer-readable instructions that direct the functions of the methods described herein, are embodiments of the present disclosure.

[0039] Figure 21 is a flow chart of a method 200 for passivating a target (e.g., target 106) in a process chamber (e.g., process chamber 100) according to some embodiments of the present disclosure. The method 200 rapidly passivates a target surface (e.g., an OTS target surface) by oxidizing the OTS material using an oxygen plasma. The high energy, high pressure oxygen plasma significantly accelerates the passivation process. The method 200 also uses a circulating purge that allows air to react with the unoxidized portion of the target.

[0040] At 202, a first gas (e.g., oxygen, argon, helium, krypton, neon, radon, xenon, or one or more other suitable non-reactive gases) can be supplied into an interior volume of a processing chamber (e.g., interior volume 148). For example, in at least some embodiments, an oxidizing gas such as oxygen can be supplied into the interior volume using one or more gas sources, such as gas source 154.

[0041] At 204, the first gas may be ignited to form a plasma and oxidize at least one of the target material or the target material deposited on the processing accessory disposed in the processing chamber. For example, one or more of an RF power source and / or a DC power source (e.g., RF power source 118 and / or DC power source 120) may be used to ignite the first gas. In at least some embodiments, the RF power source 118 may be used to ignite the first gas. To facilitate ignition of the first gas, in at least some embodiments, the first gas may be provided from a gas source 154 at about 150 sccm to about 200 sccm, a valve 160 may be used to maintain a pressure within the processing chamber 100 at about 50 mTorr to about 60 mTorr, and the RF power source 118 may provide an RF power of about 150 W to about 200 W. The oxygen plasma may be maintained for a predetermined time. For example, in at least some embodiments, the oxygen plasma may be maintained for about 2 to 3 seconds. Additionally, because plasmas (e.g., oxygen plasma and argon plasma) can heat the target to temperatures that may cause the target to crack, it may be necessary to turn the plasma on and off to allow the target to cool (e.g., plasma pulsing or cycling - plasma on - plasma off and cool - plasma on - plasma off and cool).

[0042] In at least some embodiments, before 202 and 204, another gas (e.g., a second gas) such as an inert gas may be supplied / introduced into the interior space of the processing chamber. For example, one or more of argon, helium, krypton, neon, radon, xenon, or one or more other suitable non-reactive gases may be first introduced into the interior space and ignited as described above. In an embodiment, argon may be introduced into the processing chamber and ignited to form an argon plasma. The inventors have found that forming an argon plasma (or other non-reactive plasma) may promote the formation of an oxygen plasma in the interior space. In at least some embodiments, argon may be introduced into the interior space at a flow rate of about 150 sccm to about 200 sccm. The argon plasma may be maintained for a predetermined time range before oxygen is supplied, for example, the argon plasma may be maintained for about 2 to 3 seconds. After this time, as described above, the argon supply may be turned off, and oxygen may be supplied at 202, and may be ignited at 204.

[0043] Continuing at 204, to facilitate oxidation of the target and / or processing accessories, the interior of the processing chamber can be maintained at a relatively high pressure. For example, in at least some embodiments, the interior space can be maintained at a pressure of about 50 mTorr, which is much higher than a typical deposition pressure (e.g., 0.5 mTorr). The oxygen plasma oxidizes the surface of the target and / or the surface of the processing accessory (the processing accessory may also have target material deposited thereon), thereby stabilizing the surface of the target and / or the surface of the processing accessory. More specifically, after the surface of the target and / or the processing accessory is passivated (oxidized), reaction between the target material below the oxide on the target surface and reactive species (e.g., water / moisture in the room air / environment) is prevented, and the generation of toxic byproducts is greatly reduced, if not completely eliminated. That is, after 204, the target surface covered with oxide is inert and non-toxic.

[0044] Next, at 206, a cyclic purge can be performed. More specifically, at 208, the cyclic purge can include, for example, passing air (e.g., room / fresh air) into the process chamber using the gas source 154 and the mass flow controller 156 while the process chamber remains closed. Passing air into the process chamber can cause the air to react with at least one of the target material or target material deposited on the process assembly. That is, the air reacts with the portion of the target material that was not oxidized at 204.

[0045] The air continues to be introduced into the processing chamber until a predetermined pressure is reached within the processing chamber. For example, in at least some embodiments, the predetermined pressure can be about 600 torr to about 760 torr. Once the predetermined pressure is reached, the predetermined pressure is maintained within the processing chamber for a predetermined time at 210 to produce toxic byproducts caused by the reaction of the air with at least one of the target material or the target material deposited on the processing accessory. The predetermined time can be about 5 minutes to about 30 minutes.

[0046] Next, the processing chamber can be evacuated to remove toxic byproducts at 212. For example, in at least some embodiments, a pump such as pump 161 can be used to evacuate (evacuate) the interior of the processing chamber to remove toxic byproducts (e.g., hydrides, arsine, etc.) through an exhaust port of the processing chamber, such as exhaust port 158.

[0047] In at least some embodiments, the amount of toxic byproducts in the interior space of the processing chamber can be measured using, for example, a gas detection system 163. The gas detection system 163 can measure the amount of toxic byproducts before performing method 200 and / or after each of 202-212. For example, in at least some embodiments, the gas detection system 163 can measure the amount of toxic byproducts after the first run through the cycle purge (e.g., after 212), for example, using a sensor 165. In at least some embodiments, the control feedback loop can use the data received from the sensor 165 to control the gas source 154 and / or the mass flow controller 156 to repeat 206-212, for example, until a predetermined threshold of toxic byproducts has not been reached. In such an embodiment, the data received from the sensor 165 at the gas detection system 163 can be transmitted to the controller 191, and the controller 191 can control the gas source 154 and the mass flow controller 156 to allow more air to be provided to the processing chamber 100. Additionally, using the data received from the sensor 165, the controller 191 may control the pump 161 and / or the valve 160 to obtain a predetermined pressure and / or to perform additional exhaust of the interior space of the process chamber.

[0048] Operations 202-212 or portions thereof may be repeated until the gas detection system 163 detects a predetermined threshold of toxic byproducts. For example, 202-212 or portions thereof may be repeated until the gas detection system 163 detects an amount of toxic byproducts of about 0 ppb to about 100 ppb (and in some embodiments may be about 5 ppm). In at least some embodiments, 202-204 may be repeated one or more times before 206 is performed. Similarly, 206 may be repeated one or more times before 202-204 is performed and / or repeated. For example, in some embodiments, 202-204 may be performed up to and including about 100 times before 206 is performed. In some embodiments, 206 may be performed up to and including about 5 times. In some embodiments, a cycle of 202-204 may be performed up to and including about 100 times before 206 is performed, and then 206 may be performed up to and including about 5 times. In some embodiments, the aforementioned cycle may be repeated one or more times. For example, in some embodiments, the cycle may be repeated 8 times or more. Additionally, after executing the loop, or in any other implementation, 206 can be repeated an additional one or more times, such as 1, 2, 3, 4, etc. For example, in at least some implementations, 206 can be repeated up to and including 40 times or more.

[0049] Additionally, to facilitate cooling the target to prevent overheating (or cracking) of the target during passivation, a cooling fluid may be supplied via one or more cooling channels / guides disposed in the backing plate 146 to cool the target, such as during any or all of 202 to 212 .

[0050] While the foregoing relates to embodiments of the present disclosure, other and further embodiments of the present disclosure may be envisaged without departing from the basic scope of the present disclosure.

Claims

1. A method for passivating a surface of a processing chamber, the method comprising: a) supplying an oxidizing gas into the inner space of the processing chamber; b) igniting the oxidizing gas to form a plasma and oxidize at least one of a target or a target material, the target material being deposited on a process accessory disposed in the interior space of the process chamber; and c) Perform cycle cleaning, including: c1) providing air into the process chamber to react with at least one of the target material or the target material deposited on the process kit; c2) maintaining a predetermined pressure within the process chamber for a predetermined time to produce toxic byproducts resulting from a reaction of the air with at least one of the target or the target material deposited on the process assembly; and c3) evacuating the process chamber to remove the toxic byproducts.

2. The method of claim 1, further comprising: Before the oxidizing gas is supplied into the process chamber, a non-reactive gas is supplied into the inner space of the process chamber and ignited.

3. The method of claim 2, wherein the oxidizing gas is oxygen and the non-reactive gas is an inert gas.

4. The method of claim 3, wherein the inert gas is at least one of argon, helium, krypton, neon, radon or xenon. The method of claim 1 , wherein the predetermined pressure is 600 torr to 760 torr. The method of claim 1 , wherein the predetermined time is 5 minutes to 30 minutes. 7 . The method according to claim 1 , further comprising, after b) and before c), cooling the target, and then repeating a) to b).

8. The method of claim 1, further comprising: After c3), c1) to c3) are repeated.

9. The method of claim 1, wherein the target material is made of at least one of arsenic, boron, carbon, gallium, germanium, selenium, silicon, tellurium, titanium, or tungsten.

10. The method of any one of claims 1 to 3 or 5 to 9, further comprising: At least one of after or during a) to c3), measuring the amount of the toxic byproduct in the interior space of the process chamber.

11. A non-transitory computer readable storage medium having stored thereon instructions which, when executed by a processor, perform a method of passivating a surface in a processing chamber, the method comprising: a) supplying an oxidizing gas into the inner space of the processing chamber; b) igniting the oxidizing gas to form a plasma and oxidize at least one of a target or a target material, the target material being deposited on a process accessory disposed in the interior space of the process chamber; and c) Perform cycle cleaning, including: c1) providing air into the process chamber to react with at least one of the target material or the target material deposited on the process kit; c2) maintaining a predetermined pressure within the process chamber for a predetermined time to produce toxic byproducts resulting from a reaction of the air with at least one of the target or the target material deposited on the process assembly; and c3) evacuating the process chamber to remove the toxic byproducts.

12. The non-transitory computer-readable storage medium of claim 11, further comprising: Before the oxidizing gas is supplied into the process chamber, a non-reactive gas is supplied into the inner space of the process chamber and ignited.

13. The non-transitory computer-readable storage medium of claim 12, wherein the oxidizing gas is oxygen and the non-reactive gas is an inert gas.

14. The non-transitory computer-readable storage medium of claim 13, wherein the noble gas is at least one of argon, helium, krypton, neon, radon, or xenon. 15 . The non-transitory computer readable storage medium of claim 11 , wherein the predetermined pressure is 600 Torr to 760 Torr.

16. The non-transitory computer-readable storage medium of claim 11, wherein the predetermined time is 5 minutes to 30 minutes. 17 . The non-transitory computer readable storage medium of claim 11 , further comprising cooling the target and repeating a) to b) after b) and before c).

18. The non-transitory computer-readable storage medium of claim 11, further comprising repeating c1) to c3) after c3).

19. The non-transitory computer readable storage medium of any one of claims 11 to 13 or 15 to 18, wherein the target material is made of at least one of arsenic, boron, carbon, gallium, germanium, selenium, silicon, tellurium, titanium, or tungsten.

20. A processing chamber for passivating a surface of the processing chamber, the processing chamber comprising: a target disposed in the processing chamber for sputtering target material onto a substrate disposed in the processing chamber during processing; a gas source connected to the process chamber and configured to supply an oxidizing gas into an inner space of the process chamber, and configured to supply air into the inner space of the process chamber without opening the process chamber; at least one of an RF power source or a DC power source configured to ignite the oxidizing gas to form a plasma within the processing chamber; a pump configured to maintain a predetermined pressure and to exhaust the processing chamber; a gas detection system configured to measure an amount of toxic byproducts in the interior space of the processing chamber; and a controller configured to control the processing chamber to: a) supplying the oxidizing gas from the gas source into the inner space of the processing chamber; b) igniting the oxidizing gas to form the plasma and oxidize at least one of the target material or a target material deposited on a process kit disposed in the interior space of the process chamber; and c) Perform cycle cleaning, including: c1) providing air into the process chamber to react with at least one of the target material or the target material deposited on the process kit; c2) maintaining the predetermined pressure within the process chamber for a predetermined time to produce the toxic byproducts caused by a reaction of the air with at least one of the target or the target material deposited on the process assembly; and c3) evacuating the process chamber to remove the toxic byproducts.

Images