Tio 2 high-k process with in-SITU cleanable ald

Abstract

Methods of cleaning substrate-processing chambers are provided. In one aspect, a method of in-situ cleaning a processing chamber includes introducing a reactive species into the processing chamber in which a residual film is disposed. The residual film includes deposits of a high-k dielectric material and an insulator. The high-k dielectric material is titanium dioxide. The method further includes permitting the reactive species to react with the deposits of the high-k dielectric material and the insulator so as to form a volatile byproduct. The method also includes removing the volatile byproduct from the processing chamber.

Description

TIO2 HIGH-K PROCESS WITH IN-SITU CLEANABLE ALDBACKGROUNDField

[0001] Implementations described herein generally relate to methods and apparatus for in-situ removal of unwanted deposition buildup from one or more interior surfaces of a substrate processing chamber.Description of the Related Art

[0002] Display devices have been widely used for a range of electronic applications, such as TVs, monitors, mobile phones, MP3 players, e-book readers, personal digital assistants (PDAs) and the like. The display device is generally designed for producing an image by applying an electric field to a liquid crystal that fills a gap between two substrates (e.g., a pixel electrode and a common electrode) and has anisotropic dielectric constant that controls the intensity of the dielectric field. By adjusting the amount of light transmitted through the substrates, the light and image intensity, quality and power consumption may be efficiently controlled.

[0003] A variety of different display devices, such as active matrix liquid crystal display (AMLCD) or an active matrix organic light emitting diodes (AMOLED), may be employed as light sources for display. In the manufacturing of display devices, an electronic device with high electron mobility, low leakage current and high breakdown voltage, would allow more pixel area for light transmission and integration of circuitry, resulting in a brighter display, higher overall electrical efficiency, faster response time and higher resolution displays. Low film qualities of the material layers, such as dielectric layer with impurities or low film densities, formed in the device often result in poor device electrical performance and short service life of the devices. Thus, a stable and reliable method for forming and integrating film layers within TFT and OLED devices becomes crucial to provide a device structure with low film leakage, and high breakdown voltage, for use in manufacturing electronic devices with lower threshold voltage shift and improved overall performance of the electronic device.

[0004] In particular, the interface management between a metal electrode layer and the nearby insulating materials becomes critical as improper material selection of theinterface between the metal electrode layer and the nearby insulating material may adversely result in undesired elements diffusing into the adjacent materials, which may eventually lead to current short, current leakage or device failure. Furthermore, the insulating materials with different higher dielectric constant often provide different electrical performance, such as providing different capacitance in the device structures. Selection of the insulating materials not only affects the electrical performance of the device, but incompatibility between the material of the insulating materials and the electrodes may also result in film structure peeling, poor interface adhesion, or interface material diffusion, which may eventually lead to device failure and low product yield.

[0005] In some devices, capacitors (e.g., a dielectric layer placed between two electrodes) are often utilized and formed to store electric charges when the display devices are in operation. The capacitor as formed is required to have high capacitance for display devices. The capacitance may be adjusted by changing the dielectric material and dimensions of the dielectric layer formed between the electrodes and / or thickness of the dielectric layer. For example, when the dielectric layer is replaced with a material having a higher dielectric constant, the capacitance of the capacitor will increase as well.

[0006] As the resolution requirement for display devices becomes increasingly challenging, e.g., display resolution greater than 2,000 pixels per inch (PPI), display devices have a limited area for forming capacitors to increase electrical performance. Thus, maintaining the capacitor formed in the display devices in a confined location with a relatively small area has become crucial. Higher dielectric constant (“high-k”) materials have been found to enable higher resolution display devices. However, deposition of high-k dielectric materials is not limited to the substrate and often forms a residual film throughout the interior of the processing chamber. Conventional high- k dielectric material films are difficult to remove with conventional etch species during an in-situ cleaning of the processing chamber. Conventional high-k dielectric materials include ZrO2 and HfO2.

[0007] In order to achieve high chamber availability while reducing the cost of ownership for production and maintaining film quality, a chamber clean is performedto remove residual film residue from the interior surfaces of the processing chamber including the process kits, e.g., showerhead, etc. Unfortunately, most known high-k dielectric materials have a poor clean rate during an in-situ cleaning of the processing chamber.

[0008] Therefore, a need exists for methods for in-situ removal of unwanted high- k dielectric material deposits from substrate-processing chambers.SUMMARY

[0009] In one embodiment, a method of in-situ cleaning a processing chamber is provided. The method includes introducing a reactive species into the processing chamber in which a residual film is disposed, the residual film including deposits of a high-k dielectric material and an insulator, wherein the high-k dielectric material is titanium dioxide; permitting the reactive species to react with the deposits of the high- k dielectric material and the insulator so as to form a volatile byproduct; and removing the volatile byproduct from the processing chamber.

[0010] In another embodiment, a method is provided. The method includes depositing, within a processing chamber, a first layer of a high-k dielectric material over a substrate, causing a first film layer of the high-k dielectric material to be formed on a surface of the processing chamber; depositing, within the processing chamber, at least a partial layer of an insulator over the first layer of the high-k dielectric material, causing deposits of the insulator to be formed on the first film layer; depositing, within the processing chamber, a second layer of the high-k dielectric material over the partial layer of the insulator, causing a second film layer of the high-k dielectric material to be formed on the deposits of the insulator and the first film layer, wherein at least a portion of the first film layer and the second film layer are directly connected to one another; introducing a reactive species into the processing chamber; permitting the reactive species to react with the first film layer, the second film layer, and the deposits of the insulator to form a volatile byproduct; and removing the volatile byproduct from the processing chamber.

[0011] In yet another embodiment, a method is provided. The method includes depositing a layer of high-k dielectric material over a substrate disposed in a firstprocessing chamber, causing deposits of the high-k dielectric material to be deposited on a first surface within the first processing chamber, wherein the first surface is not part of the substrate; transferring the substrate with the layer of the high-k dielectric material deposited thereon to a second processing chamber; depositing, within the second processing chamber, a layer of an insulator over the layer of the high-k dielectric material, causing deposits of the insulator to be deposited on a second surface within the second processing chamber, wherein the second surface is not part of the substrate or the layer of the high-k dielectric material deposited thereon, and wherein the layer of the insulator comprises aluminum oxide; introducing, while the substrate is not within the first processing chamber, a reactive species into the first processing chamber to permit the reactive species to react with the high-k dielectric material deposited on the first surface to form a volatile byproduct; removing the volatile byproduct from the first processing chamber; and performing an ex-situ cleaning of the second processing chamber to remove the deposits of the insulator from the second surface and from the second processing chamber.

[0012] In yet a further embodiment, a processing chamber with an in-situ cleaning system is provided. The processing chamber includes a plurality of walls defining a process volume in which a substrate can undergo a deposition process, which can include depositing one or more layers of a high-k dielectric material in combination with one or more layers of an insulator. The processing chamber further includes a remote plasma source arranged to generate a plasma that is selectively directed to the process volume in which a residual film is disposed. The residual film includes deposits of the high-k dielectric material and the insulator. With the plasma directed to the process volume, the plasma is permitted to react with the deposits of the high- k dielectric material and the insulator of the residual film so as to form a volatile byproduct, which is removable from a surface of, or disposed within, the processing chamber. The volatile byproduct can be removed from the processing chamber.

[0013] In yet another embodiment, a substrate-processing system is provided. The substrate-processing system includes a first substrate-processing chamber arranged to deposit high-k dielectric material over a substrate or other layers disposed thereon. The substrate-processing system also includes a second substrate-processing chamber arranged to deposit an insulator formed of aluminum oxide over the substrateor other layers disposed thereon. The substrate-processing system include a computing system having one or more processors and one or more memory devices (e.g., one or more non-transitory memory devices) storing a program, which, when executed, causes the one or more processors to, individually or collectively, perform an operation, comprising: depositing a layer of high-k dielectric material over a substrate disposed in a first processing chamber, with deposits of the high-k dielectric material also being deposited on a first surface of, or within, the first processing chamber, wherein the first surface is not part of the substrate; transferring the substrate with the layer of the high-k dielectric material deposited thereon to a second processing chamber (e.g., using a controllable robot arm); depositing, within a second processing chamber, a layer of an insulator over the layer of the high-k dielectric material deposited on the substrate, with deposits of the insulator also being deposited on a second surface of, or within, the second processing chamber, wherein the second surface is not part of the substrate or the layer of the high-k dielectric material deposited thereon, and wherein the layer of the insulator is formed of an aluminum oxide; introducing, with the substrate not within the first processing chamber, a reactive species into the first processing chamber to permit the reactive species to react with the high-k dielectric material deposited on the first surface so as to form a volatile byproduct that is removable from the first surface; removing the volatile byproduct from the first processing chamber; and performing an ex-situ cleaning of the second processing chamber to remove the deposits of the insulator off of the second surface and from the second processing chamber.

[0014] In still a further embodiment, a processing chamber is provided. The processing chamber includes a plurality of walls defining a process volume in which a substrate can undergo a deposition process, which can include depositing one or more layers of a high-k dielectric material (e.g., a titanium dioxide) in combination with one or more layers of an insulator. The processing chamber further includes a plasma source arranged to selectively generate a plasma (e.g., a nitrogen trifluoride plasma, NF3). The processing chamber also includes a computing system having one or more processors and one or more memory devices (e.g., one or more non-transitory memory devices) storing a program, which, when executed, causes the one or more processors to, individually or collectively, perform an operation, comprising:introducing the plasma into the process volume in which a residual film is disposed on a surface of, or disposed within, the processing chamber, the residual film including deposits of the high-k dielectric material and the insulator; permitting the plasma to react with the deposits of the high-k dielectric material and the insulator so as to form a volatile byproduct that is removable from the surface; and purging the volatile byproduct from the processing chamber.BRIEF DESCRIPTION OF THE DRAWINGS

[0015] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, may admit to other equally effective embodiments.

[0016] Figure 1 A is a schematic cross-section of a processing chamber.

[0017] Figure 1 B is a schematic cross-sectional of a processing chamber with residual film.

[0018] Figure 2 depicts a process flow diagram of a method that may be used to remove high-k dielectric materials from a substrate-processing chamber according to various embodiments.

[0019] Figure 3 depicts a process flow diagram of one implementation of a method that may be used to remove high-k dielectric materials from a substrate-processing chamber.

[0020] Figure 4 depicts a process flow diagram of one implementation of a method that may be used to remove high-k dielectric materials from a substrate-processing chamber.

[0021] Figure 5A is a schematic cross-section of a high-k dielectric layer and insulator stack on a chamber wall.

[0022] Figure 5B is a schematic cross-section of a high-k dielectric layer and partial layer of an insulator stack on a chamber wall.

[0023] Figure 6 is a schematic block diagram of a substrate-processing system.

[0024] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation.DETAILED DESCRIPTION

[0025] The following disclosure describes techniques for in-situ removal of residual high-k dielectric materials from a substrate-processing chamber. Certain details are set forth in the following description and figures to provide a thorough understanding of various implementations of the disclosure. Other details describing well-known structures and systems often associated with plasma cleaning are not set forth in the following disclosure to avoid unnecessarily obscuring the description of the various implementations.

[0026] Implementations described herein will be described below in reference to a high-k dielectric deposition process that can be carried out using any suitable thin film deposition system. Other tools capable of performing high-k dielectric deposition processes may also be adapted to benefit from the implementations described herein. In addition, any system enabling high-k dielectric deposition processes described herein can be used to advantage. The apparatus description described herein is illustrative and should not be construed or interpreted as limiting the scope of the implementations described herein.

[0027] Implementations of the present disclosure generally relate to in-situ removal of high-k dielectric materials such as TiO2 from process chambers. The processing chambers include but are not limited to PECVD, ALD or other processing chambers, which are utilized in the fabrication of high-resolution display back-plane TFT circuits. TiO2 has a dielectric constant k from about 40 to greater than 70, depending on the crystalline phase. The high k value is critical to enable high-resolution display devices.One factor for enabling TiO2 as a high-k dielectric material option is the efficient removal of residual high-k material from the processing chamber to reduce particles and improve the yield.

[0028] Typically, deposition of high-k dielectric materials is not limited to the substrate and forms a residual film throughout the chamber. This residual film can cause particle formation, uniformity degradation and gas inlet clogging, thus leading to yield loss and increased cost of ownership. One way to remove the unwanted residual film on the chamber wall or other chamber components is to dissemble the chamber and remove the films with solution or solvent periodically after several deposition cycles. Dissembling the chamber, cleaning the components and reassembling the chamber take significant time and significantly affect the uptime of the tool. Another approach is to apply plasma to promote excitation and / or dissociation of reactive gases by the application of radio frequency (RF) energy. The plasma includes highly reactive species that reacts with and etches the unwanted residual material. For example, NF3 plasma is widely used in the display industry to remove SiOx and SiNx films from processing chambers. However, NF3 plasma is often unable to etch residual conventional high-k dielectric materials such as ZrO2 and HfO2.

[0029] Implementations of the present disclosure include both a chamber cleaning process and modification of current hardware materials. Some implementations of the present disclosure use TiO2 as a high-k dielectric material in combination with an insulator during the production of high resolution displays. The insulator can be strategically added to improve leakage current. The insulator may be SiOx, SiNx or AIOx. The film including TiO2 and the insulator including SiOx or SiNx can be removed from the processing chamber by a reactive species such as NF3 plasma. The reactive species may be generated as in-situ plasma (e.g., formed inside the processing chamber) or ex-situ plasma (e.g., formed via a remote plasma source). The generation of plasma can be (but is not limited to) inductive-coupled plasma (ICP), capacitive-coupled plasma (CCP), remote plasma source (RPS), or microwave plasma. The TiO2 and the insulator including AIOx can be removed by a RPS in-situ clean followed by an ex-situ maintenance.

[0030] Figure 1 is a schematic cross-section of a processing chamber 100. The substrate-processing chamber 100 may be used to perform CVD, plasma enhanced- CVD (PE-CVD), pulsed-CVD, ALD, PE-ALD, metal-organic chemical vapor deposition (MOCVD) or combinations thereof. In some implementations, the substrateprocessing chamber may be configured to deposit a high-k dielectric layer, such as TiO2, ZrO2, or HfO2. In some implementations, the substrate-processing chamber 100 is configured to process a large area substrate 102 (hereafter substrate 102) using plasma in forming structures and devices on the substrate 102 for use in the fabrication of liquid crystal displays (LCD’s), flat panel displays, organic light emitting diodes (OLED’s), or photovoltaic cells for solar cell arrays.

[0031] The substrate-processing chamber 100 generally includes sidewalls 142, a bottom wall 104 and a lid assembly 112, which define a process volume 106. The lid assembly 112 is generally comprised of aluminum. The lid assembly 112 may be anodized to form a layer of AI2O3 on the surface of the lid assembly 112. The sidewalls 142 and the bottom wall 104 may be fabricated from a unitary block of aluminum or other material compatible for plasma processing. The sidewalls 142 and the bottom wall 104 may be anodized to form a coating material on the surface of the lid assembly 112. The coating material may be formed by an anodization process, a plasma spray process, or a thermal spray process. The coating material may include a compound selected from alumina (AI2O3), yttrium-containing compounds, and combinations thereof. The sidewalls 142 and the bottom wall 104 may be electrically grounded.

[0032] A gas distribution plate 110 and a substrate support assembly 130 are disposed within the process volume 106. The process volume 106 is accessed through a slit valve opening 108 formed through the sidewalls 142 such that the substrate 102 may be transferred into and out of the substrate-processing chamber 100.

[0033] The substrate support assembly 130 includes a substrate-receiving surface 132 for supporting the substrate 102 thereon. The substrate support assembly 130 generally comprises an electrically conductive body supported by a stem 134 that extends through the bottom wall 104. The stem 134 couples the substrate support assembly 130 to a lift system 136, which raises and lowers the substrate supportassembly 130 between substrate transfer and processing positions. A shadow frame 133 may be placed over a periphery of the substrate 102 during processing to prevent deposition on the edge of the substrate 102. Lift pins 138 are moveably disposed through the substrate support assembly 130 and are adapted to space the substrate 102 from the substrate-receiving surface 132. The substrate support assembly 130 may also include heating and / or cooling elements 139 utilized to maintain the substrate support assembly 130 at a chosen temperature. The substrate support assembly 130 may also include grounding straps 131 to provide an RF return path around the periphery of the substrate support assembly 130.

[0034] The gas distribution plate 110 is coupled at its periphery to the lid assembly 112 or sidewalls 142 of the substrate-processing chamber 100 by a suspension 114. In one particular implementation, the gas distribution plate 110 is fabricated from aluminum. The surface of the gas distribution plate may be anodized to form a coating material (e.g., AI2O3) on the surface of the gas distribution plate 110. The coating material may be formed on the surface of the gas distribution plate 110 by an anodization, plasma spray process, or thermal spray process. The gas distribution plate 110 may also be coupled to the lid assembly 112 by one or more center supports 116 to help prevent sag and / or control the straightness / curvature of the gas distribution plate 110. The gas distribution plate 110 may have different configurations with different dimensions. In an exemplary implementation, the gas distribution plate 110 has a quadrilateral plan shape. The gas distribution plate 110 has a downstream surface 150 having a plurality of apertures 111 formed through the gas distribution plate 110 and facing an upper surface 118 of the substrate 102 disposed on the substrate support assembly 130. The apertures 111 may have different shapes, number, densities, dimensions, and distributions across the gas distribution plate 110. In one or more implementations, a diameter of the apertures 111 may be selected between about 0.01 inch and about 1 inch.

[0035] A gas source 120 is coupled to the lid assembly 112 to provide gas through the lid assembly 112 and then through the apertures 111 formed in the gas distribution plate 110 to the process volume 106. A vacuum pump 109 is coupled to the substrateprocessing chamber 100 to maintain the gas in the process volume 106 at a chosen pressure.

[0036] A first source of electric power 122 is coupled with the lid assembly 112 and / or to the gas distribution plate 110. The first source of electric power 122 provides power that creates an electric field between the gas distribution plate 110 and the substrate support assembly 130 so that a plasma may be generated from the gases present between the gas distribution plate 110 and the substrate support assembly 130. The lid assembly 112 and / or the gas distribution plate 110 electrode may be coupled to the first source of electric power 122 through an optional filter, which may be an impedance matching circuit. The first source of electric power 122 may be DC power, pulsed DC power, RF bias power, pulsed RF source or bias power, or a combination thereof. In one or more implementations, the first source of electric power 122 is a RF bias power.

[0037] In one or more implementations, the first source of electric power 122 is an RF power source. In one or more implementations, the first source of electric power 122 may be operated to provide RF power at a frequency between 0.3 MHz and about 14 MHz, such as about 13.56 MHz. The first source of electric power 122 may generate RF power at about 10 Watts to about 20,000 Watts, (e.g., between about 10 Watts to about 5000 Watts; between about 300 Watts to about 1500 Watts; or between about 500 Watts and about 1000 Watts).

[0038] The substrate support assembly 130 may be grounded such that RF power supplied by the first source of electric power 122 to the gas distribution plate 110 may excite the gases disposed in the process volume 106 between the substrate support assembly 130 and the gas distribution plate 110. The substrate support assembly 130 may be fabricated from metals or other comparable electrically conductive materials. In one or more implementations, at least a portion of the substrate support assembly 130 may be covered with an electrically insulative coating. The coating may be a dielectric material such as oxides, silicon nitride, silicon dioxide, aluminum dioxide, tantalum pentoxide, silicon carbide, polyimide, among others. Alternatively, the substrate-receiving surface 132 of the substrate support assembly 130 may be free of coating or anodizing.

[0039] An electrode (not shown), which may be a bias electrode and / or an electrostatic chucking electrode, may be coupled to the substrate support assembly130. In one or more implementations, the electrode is positioned in the body of the substrate support assembly 130. The electrode may be coupled to a second source of electric power 160 through an optional filter, which may be an impedance matching circuit. The second source of electric power 160 may be used to establish additional bias by establishing additional electric potential from the plasma to the substrate 102. Although there is already built-in potential from the plasma to the substrate 102 even without the second source of electric power 160, it is believed that the second source of electric power 160 increases the bias to provide more ion bombardment to enhance the etching / cleaning effect. The second source of electric power 160 may be DC power, pulsed DC power, RF bias power, pulsed RF source or bias power, or a combination thereof.

[0040] In one or more implementations, the second source of electric power 160 is a DC bias source. The DC bias power may be supplied at between about 10 Watts and about 3000 Watts (e.g., between about 10 Watts and about 1000 Watts; or between about 10 Watts and about 100 Watts) at a frequency of 300 kHz. In one or more implementations, the DC bias power may be pulsed with a duty cycle between about 10 to about 95 percent at an RF frequency between about 500 Hz and about 10 kHz. Not to be bound by theory but it is believed that the DC bias establishes a bias between the plasma and substrate support, so that the ions in the plasma bombard the substrate support, enhancing the etching effect.

[0041] In one or more implementations, the second source of electric power 160 is a RF bias power. The RF bias power may be supplied at between about 0 Watts and about 1000 Watts (e.g., between about 10 Watts and about 100 Watts) at a frequency of 300 kHz. In one or more implementations, the RF bias power may be pulsed with a duty cycle between about 10 to about 95 percent at a RF frequency between about 500 Hz and about 10 kHz.

[0042] In one or more implementations, the edges of the downstream surface 150 of the gas distribution plate 110 may be curved so that a spacing gradient is defined between the edge and comers of the gas distribution plate 110 and substrate-receiving surface 132 and, consequently, between the gas distribution plate 110 and the upper surface 118 of the substrate 102. The shape of the downstream surface 150 may beselected to meet specific process requirements. For example, the shape of the downstream surface 150 may be convex, planar, concave or other suitable shape. Therefore, the edge to corner spacing gradient may be utilized to tune the film property uniformity across the edge of the substrate, correcting property non-uniform ity in films disposed in the corner of the substrate. Additionally, the edge to center spacing may also be controlled so film property distribution uniformity may be controlled between the edge and center of the substrate. In one or more implementations, a concave curved edge of the gas distribution plate 110 may be used so the center portion of the edge of the gas distribution plate 110 is spaced farther from the upper surface 118 of the substrate 102 than the corners of the gas distribution plate 110. In another implementation, a convex curved edge of the gas distribution plate 110 may be used so that the corners of the gas distribution plate 110 are spaced farther than the edges of the gas distribution plate 110 from the upper surface 118 of the substrate 102.

[0043] A remote plasma source 124, such as an inductively coupled remote plasma source, may also be coupled between the gas source and the gas distribution plate 110. Between processing substrates, a halogen-containing cleaning gas mixture may be energized in the remote plasma source 124 to remotely provide plasma utilized to clean chamber components. The halogen-containing cleaning gas mixture entering the process volume 106 may be further excited by the RF power provided to the gas distribution plate 110 by the first source of electric power 122. Although gas source 120 is coupled to the lid assembly 112 via the remote plasma source 124, it should be understood that in some implementations, the gas source 120 is coupled directly to the lid assembly.

[0044] In one or more implementations, the substrate 102 that may be processed in the substrate-processing chamber 100 may have a surface area of 10,000 cm2or more, such as 25,000 cm2or more, for example about 55,000 cm2or more. It is understood that after processing the substrate may be cut to form smaller other devices.

[0045] In one or more implementations, the heating and / or cooling elements 139 may be set to provide a substrate support assembly temperature during cleaning of about 600 degrees Celsius or less (between about 10 degrees Celsius and about 300degrees Celsius; between about 200 degrees Celsius and about 300 degrees Celsius; between about 10 degrees Celsius and about 50 degrees Celsius, or between about 10 degrees Celsius and 30 degrees Celsius).

[0046] The nominal spacing during cleaning between the upper surface 118 of the substrate 102 disposed on the substrate-receiving surface 132 and the gas distribution plate 110 may generally vary between 400 mils and about 1 ,200 mils, such as between 400 mils and about 800 mils, or other distance to obtain sought after deposition results. In one or more implementations, where the gas distribution plate 110 has a concave downstream surface, the spacing between the center portion of the edge of the gas distribution plate 110 and the substrate-receiving surface 132 is between about 400 mils and about 1 ,400 mils, and the spacing between the corners of the gas distribution plate 110 and the substrate-receiving surface 132 is between about 300 mils and about 1 ,200 mils.

[0047] FIG. 1 B depicts a sectional view of the substrate-processing chamber 100 of FIG. 1A with the substrate 102 removed. FIG. 1 B provides an illustration of the substrate-processing chamber 100 suitable for performing chamber cleaning using an internal energy source such as in-situ plasma or an external energy source, respectively. In FIG. 1 B, a reactive species 170 (depicted in FIG. 1 B as solid arrows) is introduced into the process volume 106, which has a residual film 180 (e.g., a high- k dielectric material such as TiO2) to be removed during the cleaning process. In certain embodiments the residual film 180 may include an insulator. The insulator may include be SiOx, SiNx or AIOx. In other embodiments the residual film 180 may be a film stack including multiple film layers of TiO2 and an insulator. As shown in FIG. 1 B, the residual film 180 is deposited upon at least a portion of the exposed surface within the substrate-processing chamber 100, particularly, the gas distribution plate 110, substrate support assembly 130, shadow frame 133, etc. The reactive agent 170 is exposed to an energy source, such as the first source of electric power 122, the second source of electric power 160, or remote plasma source 124, which creates reactive species 190 such as chlorine radicals, fluorine radicals, bromine radicals, hydrogen radicals and combinations thereof. The reactive species 190 react with the residual film 180 and form a volatile product. The volatile product is removed from the substrate-processing chamber 100. One or more interior surfaces (e.g., the gasdistribution plate 110, substrate support assembly 130, shadow frame 133, sidewalls 142, etc.) of the substrate-processing chamber 100 have at least one coating material (e.g., exposed AI2O3 film) formed thereon.

[0048] Figure 2 depicts a process flow diagram of one implementation of a method 200 that may be used to remove high-k dielectric materials from a substrateprocessing chamber. The substrate-processing chamber may be similar to the substrate-processing chamber 100 depicted in FIG. 1A and FIG. 1 B. In one or more embodiments, the substrate-processing chamber can include a computing system having one or more processors and one or more memory devices (e.g., one or more non-transitory memory devices) storing a program, which, when executed, causes the one or more processors to, individually or collectively, perform an operation, such as one or more aspects of the method 200. The computing system can control various controllable devices of the substrate-processing chamber to implement aspects of the method 200. In one or more embodiments, the computing system can be configured in a same or similar manner as the computing system 640 depicted in FIG. 6.

[0049] At operation 210, a high-k dielectric material is deposited over a substrate disposed in a substrate-processing chamber. During deposition of the high-k dielectric material over the substrate, the high-k dielectric material may be deposited over the interior surfaces including the chamber components (e.g., the gas distribution plate, substrate support assembly, shadow frame, sidewalls, etc.) of the substrateprocessing chamber. Any suitable high-k dielectric material may be deposited in the substrate-processing chamber. In some implementations, the high-k dielectric material is titanium dioxide TiO2. In one or more implementations, the high-k dielectric material is doped. The high-k dielectric material may be deposited using, for example, a chemical vapor deposition (CVD) process, a plasma-enhanced chemical vapor deposition (PECVD) process, an atomic layer deposition (ALD) process, a metalorganic chemical vapor deposition (MOCVD) process, and a physical vapor deposition (PVD) process. In some implementations, at least a portion of the chamber components are composed of aluminum. In some implementations, at least a portion of the chamber components have a coating disposed thereon. In some implementations, the coating includes a compound selected from alumina (AI2O3), yttrium-containing compounds, and combinations thereof. In one or moreimplementations, the yttrium-containing compound is selected from yttrium oxide (Y2O3), yttrium oxide fluoride (YOF), yttrium chlorate (Y(CIO3)3), yttrium (III) fluoride (YF3), yttrium (III) chloride (YCI3), yttria-stabilized zirconia (YSZ), and combinations thereof.

[0050] At operation 220, an insulator is deposited onto the high-k dielectric material by deposition. In certain embodiments the insulator may include SiOx or SiNx. In some embodiments, operation 210 and 220 are repeated until a desired thickness is reached. In some embodiments, the thickness may be determined by a desired ratio of high-k dielectric material to SiOx or SiNx, where the ratio of TiO2 to SiOx may be about 2.7 to about 4.8 and where the ratio of TiO2 to SiNx may be about 8 to about 13. As seen in Figure 5A, a film stack 500 of alternating layers of high-k dielectric material 510 and an insulator 520 are formed on the chamber wall 530.

[0051] In the same or other embodiments, the insulator 520 may be deposited onto the chamber wall 530 at operation 210 and the high-k dielectric material 510 may be deposited onto the insulator 520 at operation 220.

[0052] At operation 230, the substrate 102 is transferred out of the processing chamber 100. For instance, a robotic arm of a transfer module can pick up and remove the substrate 102 from the processing chamber 100. The robotic arm can be controlled by the computing system.

[0053] At operation 240, a reactive species is introduced into the processing chamber 100. The reactive species may be generated utilizing plasma. The plasma may be generated in-situ or the plasma may be generated ex-situ (e.g., remotely). Suitable plasma generation techniques and sources, such as inductive-coupled plasma (ICP), capacitive-coupled plasma (CCP), remote plasma source (RPS), or microwave plasma generation techniques may be utilized to form the reactive species. In some implementations, the reactive species are formed in-situ via an in-situ plasma process. In some implementations, the reactive species are formed ex-situ via a remote plasma source. In some embodiments, the reactive species may be NF3.

[0054] In at least one embodiment, a predetermined volume of the reactive species can be introduced into the processing chamber 100. In one or more embodiments, apredetermined volume of the reactive species can be introduced into the processing chamber 100 at a predetermined time interval. In some embodiments, the volume of the reactive species introduced into the processing chamber 100 at the predetermined time interval can change. For instance, the volume of the reactive species introduced into the processing chamber 100 can reduce each interval, such as at a predetermined rate from one interval to the next.

[0055] At operation 250, the reactive species reacts with the high-k dielectric material 510 and the insulator 520 to form a volatile byproduct. This reaction removes the residual material 180 including the high-k dielectric material 510 and the insulator 520 from the chamber wall 530. In at least one embodiment, the reactive species introduced into the processing chamber can be permitted to react with the high-k dielectric material 510 and the insulator 520 for a predetermined time, until one or more conditions are met, etc.

[0056] At optional operation 260, the volatile byproduct is purged out of the processing chamber 100. For instance, the computing system can control the processing system 100 to flow a purge gas therethrough so that volatile byproduct is removed therefrom, e.g., exhausted out of the processing chamber 100. In this regard, the processing chamber 100 may be actively purged by flowing a purge gas into the processing chamber 100. Alternatively, or in addition to introducing the purge gas, the processing chamber 100 may be depressurized in order to remove any residual cleaning gas as well as any byproducts from the processing chamber 100. The processing chamber 100 may be purged by evacuating the processing chamber 100. The time-period of the purge process should generally be long enough to remove the volatile products from the processing chamber 100. The time-period of purge gas flow should be generally long enough to remove the volatile products from the interior surfaces of the chamber including the chamber components.

[0057] At operation 270, operations 240, 250, and / or 260 may repeat until a clean endpoint is reached. It should be understood that several cycles of cleaning may apply with an optional purge process performed in between cleaning cycles.

[0058] Figure 3 depicts a process flow diagram of one implementation of a method 300 that may be used to remove high-k dielectric materials from a substrateprocessing chamber. The substrate-processing chamber may be similar to the substrate-processing chamber 100 depicted in FIG. 1A and FIG. 1 B. In one or more embodiments, the substrate-processing chamber can include a computing system having one or more processors and one or more memory devices (e.g., one or more non-transitory memory devices) storing a program, which, when executed, causes the one or more processors to, individually or collectively, perform an operation, such as one or more aspects of the method 300. The computing system can control various controllable devices of the substrate-processing chamber to implement aspects of the method 300. In one or more embodiments, the computing system can be configured in a same or similar manner as the computing system 640 depicted in FIG. 6.

[0059] At operation 310, a high-k dielectric material is deposited over a substrate disposed in a substrate-processing chamber. During deposition of the high-k dielectric material over the substrate, the high-k dielectric material may be deposited over the interior surfaces including the chamber components (e.g., the gas distribution plate, substrate support assembly, shadow frame, sidewalls, etc.) of the substrateprocessing chamber. Any suitable high-k dielectric material may be deposited in the substrate-processing chamber. In one or more implementations, the high-k dielectric material is titanium dioxide TiO2. In one or more implementations, the high-k dielectric material is doped, such as with aluminum or silicon. The high-k dielectric material may be deposited using, for example, a chemical vapor deposition (CVD) process, a plasma-enhanced chemical vapor deposition (PECVD) process, an atomic layer deposition (ALD) process, a metal-organic chemical vapor deposition (MOCVD) process, and a physical vapor deposition (PVD) process. In some implementations, at least portions of the chamber components are composed of aluminum. In some implementations, at least portions of the chamber components have a coating disposed thereon. In some implementations, the coating includes a compound selected from alumina (AI2O3), yttrium-containing compounds, and combinations thereof. In one or more implementations, the yttrium-containing compound is selected from yttrium oxide (Y2O3), yttrium oxide fluoride (YOF), yttrium chlorate (Y(CIO3)3),yttrium (III) fluoride (YF3), yttrium (III) chloride (YCI3), yttria-stabilized zirconia (YSZ), and combinations thereof.

[0060] At operation 320, a partial layer of an insulator 540 is deposited onto the high-k dielectric material 510 by deposition. In certain embodiments, the insulator may include AIOx. In some embodiments, the thickness may be determined by a desired ratio of high-k dielectric material to AIOx. In some embodiments, the ratio of TiO2 to AIOx is about 2.7 to about 4.8. In some embodiments, operation 310 and 320 are repeated until a desired thickness is reached. In certain embodiments, AIOx is partially disposed over the high-k dielectric material. As seen in Figure 5B, a film stack 501 of alternating layers of high-k dielectric material 510 and a partial layer of an insulator 540 are formed on the chamber wall 530. Some portions of adjacent layers of the high-k dielectric material 510 are connected to one another, even with a partial layer of the insulator 540 disposed therebetween.

[0061] In other embodiments, the insulator may be deposited onto the chamber wall 530 at operation 310 and the high-k dielectric material 510 may be deposited onto the insulator 540 at operation 320.

[0062] At operation 330 the substrate 102 is transferred out of the processing chamber 100. For instance, a robotic arm of a transfer module can pick up and remove the substrate 102 from the processing chamber 100. The robotic arm can be controlled by the computing system.

[0063] At operation 340, a reactive species is introduced into the processing chamber 100. The reactive species may be generated utilizing plasma. The plasma may be generated in-situ or the plasma may be generated ex-situ (e.g., remotely). Suitable plasma generation techniques and sources, such as inductively-coupled plasma (ICP), capacitively-coupled plasma (CCP), remote plasma source (RPS), or microwave plasma generation techniques may be utilized to form the reactive species. In some implementations, the reactive species are formed in-situ via an in-situ plasma process. In some implementations, the reactive species are formed ex-situ via a remote plasma source. In some embodiments, the reactive species may be NF3.

[0064] At operation 350, the reactive species reacts with the high-k dielectric material 510 and the partial layer of the insulator 540 to form a volatile byproduct. This reaction removes the residual material 180 including the high-k dielectric material 510 and the insulator 540 from the chamber wall 530.

[0065] At optional operation 360, the volatile byproduct is purged out of the processing chamber 100. The partial layer of the insulator 540 allows for AIOx to be removed with the TiO2 during the NF3 RPS. For instance, the computing system can control the processing system 100 to flow a purge gas therethrough so that volatile byproduct is removed therefrom, e.g., exhausted out of the processing chamber 100. In this way, the processing chamber 100 may be actively purged by flowing a purge gas into the processing chamber 100. Alternatively, or in addition to introducing the purge gas, the processing chamber 100 may be depressurized in order to remove any residual cleaning gas as well as any byproducts from the processing chamber 100. The processing chamber 100 may be purged by evacuating the processing chamber 100. The time-period of the purge process should generally be long enough to remove the volatile products from the processing chamber 100. The time-period of purge gas flow should be generally long enough to remove the volatile products from the interior surfaces of the chamber including the chamber components.

[0066] At operation 370, operations 340, 350, 360 and / or 270 may repeat until a clean endpoint is reached. It should be understood that several cycles of cleaning may apply with an optional purge process performed in between cleaning cycles.

[0067] Figure 4 depicts a process flow diagram of one implementation of a method 400 that may be used to remove high-k dielectric materials from a substrateprocessing chamber. In one or more embodiments, the method 400 can be implemented by a substrate-processing system, such as the substrate-processing system 600 of FIG. 6. The substrate-processing system 600 can include a first substrate-processing chamber 610 arranged to deposit high-k dielectric material over a substrate or other layers disposed thereon. The substrate-processing system 600 also includes a second substrate-processing chamber 620 arranged to deposit an insulator formed of aluminum oxide over the substrate or other layers disposed thereon. The substrate-processing system 600 can further include a transfer module630, which can transfer the substrate at least between the first and second substrateprocessing chambers 610, 620. Also, the substrate-processing system 600 can include a computing system 640 having one or more processors 642 and one or more memory devices 644 (e.g., one or more non-transitory memory devices) storing a program 646, which, when executed, causes the one or more processors 642 to, individually or collectively, perform an operation, such as one or more aspects of the method 400. The computing system 640 can be communicatively coupled with the first substrate-processing chamber 610, the second substrate-processing chamber 620, and the transfer module 630, e.g., by one or more wired and / or wireless communication lines. The first and / or second substrate-processing chambers 610, 620 may be similar to the substrate-processing chamber 100 depicted in FIG. 1A and FIG. 1 B.

[0068] At operation 405, a high-k dielectric material is deposited over a substrate disposed in a first substrate-processing chamber. For instance, the first substrateprocessing chamber 610 of FIG. 6 can be controlled by the computing system 640 to deposit the high-k dielectric material over the substrate. During deposition of the high- k dielectric material over the substrate, the high-k dielectric material may be deposited over the interior surfaces including the chamber components (e.g., the gas distribution plate, substrate support assembly, shadow frame, sidewalls, etc.) of the substrateprocessing chamber. Any suitable high-k dielectric material may be deposited in the substrate-processing chamber. In one or more implementations, the high-k dielectric material is titanium dioxide TiO2. In one or more implementations, the high-k dielectric material is doped. The high-k dielectric material may be deposited using, for example, a chemical vapor deposition (CVD) process, a plasma-enhanced chemical vapor deposition (PECVD) process, an atomic layer deposition (ALD) process, a metalorganic chemical vapor deposition (MOCVD) process, and a physical vapor deposition (PVD) process. In some implementations, at least portions of the chamber components are composed of aluminum. In some implementations, at least portions of the chamber components have a coating disposed thereon. In some implementations, the coating includes a compound selected from alumina (AI2O3), yttrium-containing compounds, and combinations thereof. In one or more implementations, the yttrium-containing compound is selected from yttrium oxide(Y2O3), yttrium oxide fluoride (YOF), yttrium chlorate (Y(CIO3)3), yttrium (III) fluoride (YF3), yttrium (III) chloride (YCI3), yttria-stabilized zirconia (YSZ), and combinations thereof.

[0069] At operation 410, the substrate is transferred out of the first processing chamber. For instance, after the high-k dielectric material is deposited over the substrate, the substrate with the high-k dielectric material deposited thereon can be transferred out of the first substrate-processing chamber, e.g., and to a transfer module. By way of example, as shown in FIG. 6, the transfer module 630, or robotic arm thereof, can be controlled by the computing system 640 to remove the substrate from the first substrate-processing chamber 610.

[0070] At operation 415, the substrate is transferred into a second processing chamber. For instance, after the substrate with the high-k dielectric material deposited thereon is transferred out of the first substrate-processing chamber and to the transfer module, the substrate with the high-k dielectric material deposited thereon can be transferred from the transfer module to the second substrate-processing chamber. By way of example, as illustrated in FIG. 6, the transfer module 630, or robotic arm thereof, can be controlled by the computing system 640 to move the substrate into the second substrate-processing chamber 620.

[0071] At operation 420, an insulator 520 is deposited onto the high-k dielectric material 510 by deposition. For instance, the second substrate-processing chamber 620 of FIG. 6 can be controlled by the computing system 640 to deposit the insulator onto the high-k dielectric material. In certain embodiments the insulator may include AIOx. In some embodiments, the thickness may be determined by a desired ratio of high-k dielectric material to AIOx. In some embodiments, the ratio of TiO2 to AIOx is about 2.7 to about 4.8. In some embodiments, operation 405, 410, 415 and 420 are repeated until a desired thickness is reached. In certain embodiments, AIOx is disposed over the high-k dielectric material. As seen in Figure 5A, a film stack 501 of alternating layers of high-k dielectric material 510 and an insulator 520 are formed on the chamber wall 530. In one or more embodiments, the layers of the insulator 520 are continuous layers that fully separate the layers of the high-k dielectric material 510from each other. In this regard, the layers of the high-k dielectric material 510 are not directly connected with other layers of the high-k dielectric material 510.

[0072] At operation 425, the substrate is transferred out of the first or second processing chamber. By way of example, with reference to FIG. 6, the transfer module 630, or robotic arm thereof, can be controlled by the computing system 640 so that the substrate is not present in the first substrate-processing chamber 610 or the second substrate-processing chamber 620. In this way, cleaning operations can be commenced.

[0073] At operation 430, a reactive species is introduced into the first processing chamber. In some embodiments, the reactive species may be NF3. In at least one example, the computing system 640 can control the first substrate-processing chamber 610 to perform a cleaning operation, such as by controlling a reactive species, such as a nitrogen trifluoride plasma, NF3, into the process volume of the first substrate-processing chamber 610. In some embodiments, the plasma may be generated in-situ or the plasma may be generated ex-situ (e.g., remotely). Suitable plasma generation techniques and sources, such as inductively-coupled plasma (ICP), capacitively-coupled plasma (CCP), remote plasma source (RPS), or microwave plasma generation techniques may be utilized to form the reactive species. In some implementations, the reactive species are formed in-situ via an in-situ plasma process. In some implementations, the reactive species are formed ex-situ via a remote plasma source.

[0074] At operation 435, the reactive species reacts with the high-k dielectric material 510. This reaction removes the residual material 180 including the high-k dielectric material 510 from the chamber wall 530. In at least one embodiment, the reactive species introduced into the first substrate-processing chamber 610 can be permitted to react with the high-k dielectric material 510 for a predetermined time, until one or more conditions are met, etc.

[0075] At optional operation 440, the volatile byproduct is purged out of the first processing chamber. For instance, the computing system 640 can control the first substrate-processing chamber 610 to flow a purge gas therethrough so that the volatilebyproduct is removed therefrom. In one or more embodiments, the volatile product can be purged in a gaseous state out of the processing chamber 100. Alternatively, or in addition to introducing the purge gas, the first substrate-processing chamber 610 may be depressurized in order to remove any residual cleaning gas as well as any byproducts from the first substrate-processing chamber 610. The first substrateprocessing chamber 610 may be purged by evacuating the substrate-processing chamber. The time-period of the purge process should generally be long enough to remove the volatile products from the first substrate-processing chamber 610. The time-period of purge gas flow should be generally long enough to remove the volatile products from the interior surfaces of the chamber including the chamber components.

[0076] At operation 445, operations 430, 435, 440 and / or 445 may repeat until a clean endpoint is reached. It should be understood that several cycles of cleaning may apply with an optional purge process performed in between cleaning cycles.

[0077] At operation 450 an ex-situ maintenance is performed to remove the insulator 520. Removal of AIOx by ex-situ maintenance does not need to occur during every cleaning cycle because the AIOx is formed as a thin layer that does not disrupt processing. Ex-situ maintenance occurs once the accumulation of AIOx accumulates to an undesired thickness as a film stack after multiple deposition steps.

[0078] At operation 455, operation 450 may repeat until a clean endpoint is reached. It should be understood that a plurality of cycles of ex-situ cleaning may apply.

[0079] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

CLAIMS:1 . A method of in-situ cleaning a processing chamber, the method comprising: introducing a reactive species into the processing chamber in which a residual film is disposed, the residual film including deposits of a high-k dielectric material and an insulator, wherein the high-k dielectric material is titanium dioxide; permitting the reactive species to react with the deposits of the high-k dielectric material and the insulator so as to form a volatile byproduct; and removing the volatile byproduct from the processing chamber.

2. The method of claim 1 , wherein the residual film is a film stack having at least a layer of the insulator separating a first layer of the high-k dielectric material and a second layer of the high-k dielectric material.

3. The method of claim 2, wherein the layer of the insulator is formed of silicon oxide or silicon nitride.

4. The method of claim 1 , wherein the residual film is a film stack having a partial layer of the insulator arranged between a first layer of the high-k dielectric material and a second layer of the high-k dielectric material, with the partial layer being partially disposed over the first layer of the high-k dielectric material such that at least a portion of the first and second layers of the high-k dielectric material are directly connected to one another.

5. The method of claim 4, wherein the partial layer of the insulator is formed of silicon oxide or silicon nitride.

6. The method of claim 4, wherein the partial layer of the insulator is formed of an aluminum oxide, and the reactive species introduced into the processing chamber is a nitrogen trifluoride plasma.

7. The method of claim 1 , wherein removing the volatile byproduct from the processing chamber comprises purging the volatile byproduct out of the processing chamber.

8. The method of claim 1 , wherein, prior to the introducing, a deposition process is performed by: depositing a layer of the high-k dielectric material over a substrate disposed in the processing chamber; and depositing a layer of the insulator, or a partial layer thereof, over the layer of the high-k dielectric material deposited on the substrate.

9. The method of claim 8, further comprising: transferring, after performing the deposition process, the substrate from the processing chamber, and wherein the reactive species is introduced into the processing chamber after the substrate is transferred out of the processing chamber.

10. A method, comprising: depositing, within a processing chamber, a first layer of a high-k dielectric material over a substrate, causing a first film layer of the high-k dielectric material to be formed on a surface of the processing chamber; depositing, within the processing chamber, at least a partial layer of an insulator over the first layer of the high-k dielectric material, causing deposits of the insulator to be formed on the first film layer; depositing, within the processing chamber, a second layer of the high-k dielectric material over the partial layer of the insulator, causing a second film layer of the high-k dielectric material to be formed on the deposits of the insulator and the first film layer, wherein at least a portion of the first film layer and the second film layer are directly connected to one another; introducing a reactive species into the processing chamber; permitting the reactive species to react with the first film layer, the second film layer, and the deposits of the insulator to form a volatile byproduct; and removing the volatile byproduct from the processing chamber.11 . The method of claim 10, wherein the reactive species introduced into the processing chamber is a nitrogen trifluoride plasma.

12. The method of claim 10, wherein the insulator is formed of silicon oxide or silicon nitride.

13. The method of claim 10, wherein the insulator is formed of aluminum oxide.

14. The method of claim 10, wherein the reactive species is provided to the processing chamber by a remote plasma source.

15. The method of claim 10, wherein the high-k dielectric material is formed of titanium dioxide.

16. A method, comprising: depositing a layer of high-k dielectric material over a substrate disposed in a first processing chamber, causing deposits of the high-k dielectric material to be deposited on a first surface within the first processing chamber, wherein the first surface is not part of the substrate; transferring the substrate with the layer of the high-k dielectric material deposited thereon to a second processing chamber; depositing, within the second processing chamber, a layer of an insulator over the layer of the high-k dielectric material, causing deposits of the insulator to be deposited on a second surface within the second processing chamber, wherein the second surface is not part of the substrate or the layer of the high-k dielectric material deposited thereon, and wherein the layer of the insulator comprises aluminum oxide; introducing, while the substrate is not within the first processing chamber, a reactive species into the first processing chamber to permit the reactive species to react with the high-k dielectric material deposited on the first surface to form a volatile byproduct; removing the volatile byproduct from the first processing chamber; and performing an ex-situ cleaning of the second processing chamber to remove the deposits of the insulator from the second surface and from the second processing chamber.

17. The method of claim 16, wherein the layer of the high-k dielectric material is formed of titanium dioxide.

18. The method of claim 16, wherein the layer of the insulator is formed as a continuous layer over the layer of the high-k dielectric material deposited on the substrate, the continuous layer of the insulator fully separating the layer of the high-k dielectric material from another layer of the high-k dielectric material deposited on the continuous layer of the insulator.

19. The method of claim 16, wherein the reactive species introduced into the first processing chamber is a nitrogen trifluoride plasma.

20. The method of claim 16, wherein the reactive species is provided to the first processing chamber by a remote plasma source.

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