Bending compensation for semiconductor substrates using plasma jets

Abstract

Methods and apparatus for bend compensation of a semiconductor substrate or wafer using a plasma jet are provided. In some embodiments, the apparatus may be used for surface modification of a backside of a substrate having a front side with electronic device features processed thereon. The apparatus may include, among other components, a nozzle configured to direct a plasma jet onto the backside of the substrate to deposit a material on the backside of the substrate, where a backside layer includes the material; an actuator (e.g., a chuck) configured to adjustably position the backside of the substrate relative to the nozzle during deposition of the backside layer; and a controller arranged to cause the plasma jet to deposit the backside layer on the backside of the substrate in a manner that causes the backside layer to have different characteristics that vary at different locations of the backside layer.

Description

[0001] By incorporating via reference The PCT application forms are filed together with this specification as part of this application. Each application identified in the concurrently filed PCT application forms that claims a benefit or priority under this application is incorporated herein by reference in its entirety for all purposes. Background Technology

[0002] Semiconductor manufacturing processes involve numerous deposition and etching operations, which can cause bending and warping of the semiconductor substrate (e.g., a wafer). For example, when film layers are stacked one on top of the other during processing, and when the deposited layers accumulate on the front side of the substrate, more stress is introduced to the substrate. Sufficiently large net compressive or tensile stresses can cause substrate bending, where a deviation occurs relative to the plane of the substrate (e.g., the average mid-plane of the substrate). Semiconductor substrates can be highly sensitive to such deviations. It is desirable to mitigate substrate deformation or bending during the manufacturing process.

[0003] The prior art and background descriptions contained herein are provided only for the purpose of giving a general overview of the background of this disclosure. The majority of this disclosure presents the work of the inventors of this case, and is not merely described in the background section or presented elsewhere in this document as background because of such work, but is therefore acknowledged as prior art. Summary of the Invention

[0004] In one aspect of this disclosure, an apparatus for surface modification of the back side of a substrate is disclosed. In some embodiments, the substrate may have a front side having electronic device features processed thereon, and the apparatus may include: a nozzle configured to direct a plasma jet onto the back side of the substrate to deposit material on the back side of the substrate and form a back side layer comprising the material; an actuator configured to adjustably position the back side of the substrate relative to the nozzle during the deposition of the material; and a controller configured to cause the plasma jet to deposit the material onto the back side of the substrate in such a manner that the formed back side layer has different characteristics varying at different locations on the back side layer.

[0005] In another aspect of this disclosure, a method for depositing a backside layer on the back side of a substrate is disclosed. In some embodiments, the substrate may have a front side having electronic device features processed thereon, and the method may include the steps of: depositing a material at a first location on the back side of the substrate, wherein the backside layer contains the material, wherein the backside layer at the first location has a first value of a characteristic, wherein the material is deposited at the first location by a plasma jet emitted from a nozzle disposed near the first location; moving the nozzle and / or the substrate to position the nozzle at a second location near the back side of the substrate; and depositing the material at the second location as the nozzle approaches the second location, wherein the backside layer at the second location has a second value of the characteristic, the second value of the characteristic being different from the first value of the characteristic.

[0006] These and other features of the disclosed embodiments will be described in detail below with reference to the accompanying drawings. Attached Figure Description

[0007] Figure 1A is an exemplary cross-sectional view of a substrate having a front layer and a back layer.

[0008] Figures 1B and 1C show simplified cross-sectional views of substrates with and without any bends.

[0009] According to some embodiments, Figure 2 is a simplified block diagram of a system configured to provide a pressurized jet of plasma radicals toward the back side of a semiconductor substrate.

[0010] Figure 2A shows an enlarged, vertical cross-sectional view of the nozzle used in the system of Figure 2 in some implementation schemes.

[0011] Figure 2B is an exemplary view of plasma radicals with shielding gas guided toward the edge of the substrate according to some implementation of the system of Figure 2.

[0012] Figure 3 is a simplified block diagram of another system configured to provide a pressurized jet of plasma radicals toward the back side of a semiconductor substrate, according to some embodiments.

[0013] Figure 3A shows an exemplary cross-sectional view of a substrate that can be processed using the system of Figure 3.

[0014] Figure 3B is a top view of the substrate depicted in Figure 3A.

[0015] Figures 4A-4D are illustrative exemplary patterns of deposition or etching using the system of Figure 2 or Figure 3.

[0016] According to some embodiments, Figure 5 is a flowchart illustrating a method for depositing a back-side layer on the back side of a substrate.

[0017] Figure 6 shows a simplified block diagram of the system or apparatus as described herein. Detailed Implementation

[0018] The following terms are used throughout this instruction manual: "Manufacturing equipment" refers to equipment in which manufacturing processes are performed. Manufacturing equipment typically has a processing chamber in which workpieces are present during processing. Generally, when in use, manufacturing equipment performs one or more semiconductor device fabrication operations. Examples of manufacturing equipment for semiconductor device fabrication include: deposition reactors, such as electroplating tanks, physical vapor deposition reactors, chemical vapor deposition reactors, and atomic layer deposition reactors; and subtractive process reactors, such as dry etching reactors (e.g., chemical and / or physical etching reactors), wet etching reactors, and ashing tanks. In some embodiments, manufacturing equipment may be a multi-station processing chamber with, for example, four stations.

[0019] As mentioned herein, the manufacturing equipment is sometimes simply referred to as a "processing chamber." In various embodiments, the processing chamber is typically a sealed container in which the substrate is held during processing. The processing chamber may include components associated with gas delivery and removal. It may also include components associated with generating plasma within the chamber and controlling the characteristics of that plasma. It may include components for controlling pressure (including evacuating the chamber). Within the context of this disclosure, the processing chamber may include a base on which the substrate rests during processing. The base may be equipped with a chuck (e.g., an electrostatic chuck) to hold the substrate in place during processing.

[0020] As used herein, a “semiconductor device fabrication operation” is an operation performed during the fabrication of a semiconductor device. As mentioned herein, such a fabrication operation is sometimes simply referred to as a “process” or “treatment.” Examples of treatments include depositing material on a substrate, selectively etching material from a substrate, and ashing photoresist on a substrate. Typically, an overall fabrication process comprises multiple semiconductor device fabrication operations, each performed in its own semiconductor fabrication tool (e.g., plasma reactor, electroplating bath, chemical mechanical planarization tool, wet etching tool, etc.). Categories of semiconductor device fabrication operations include subtractive processes (e.g., etching processes and planarization processes) and additive processes (e.g., deposition processes such as physical vapor deposition, chemical vapor deposition, atomic layer deposition, electrochemical deposition, electroless deposition)). In the context of etching processes, a substrate etching process includes the process of etching a mask layer, or more generally, the process of etching any material layers pre-deposited on and / or otherwise present on the substrate surface. Such etching processes can etch layer stacks within a substrate.

[0021] The terms “semiconductor wafer,” “wafer,” “semiconductor substrate,” “substrate,” “wafer substrate,” and “partially processed integrated circuit” are used interchangeably. Those skilled in the art will understand that the term “partially processed integrated circuit” can refer to a semiconductor wafer during any stage of the integrated circuit fabrication process on which it is located. Wafers or substrates used in the semiconductor device industry typically have diameters of 200 mm, 300 mm, or 450 mm. Examples of semiconductor substrate materials include silicon (Si), gallium arsenide (GaAs), and silicon germanium (SiGe).

[0022] Besides semiconductor substrates, other workpieces that can utilize the disclosed embodiments include various articles such as magnetic recording media, magnetic recording sensors, mirrors, optical elements, display devices or components (e.g., the backplane of a pixelated display device), flat panel displays, micromechanical devices, and so on. Workpieces can have various shapes, sizes, and materials.

[0023] As used herein, “wafer bending” or “substrate bending” can refer to deformation of a substrate or wafer. This deformation may have radial and / or azimuth components. Examples of types of wafer bending include dome shapes, disk shapes, and potato chip shapes. For example, wafer bending can occur during processing due to stress on the wafer during material deposition on the effective surface of the wafer substrate. Wafer bending can occur during various types of processing, such as when depositing large stacks of material. Wafer bending can complicate subsequent processing steps. For example, if the amount of bending is too large, the wafer may not be properly clamped. Furthermore, certain processing steps (such as photolithography) may produce undesirable results if performed on an excessively bent wafer.

[0024] Wafer curvature can be measured as the deviation of the midpoint or median distance of the wafer surface relative to a reference plane. The median point of the wafer surface can be the center point of the wafer (e.g., in the case of concave or dome-shaped curvature) or an edge point and / or the average edge point of the wafer (e.g., in the case of warped or convex curvature).

[0025] This disclosure relates to compensation for bending or other misalignments in semiconductor substrates. Semiconductor fabrication processes involve the formation of various structures, such as on the front side of a substrate, which can lead to bending. Bending is a significant problem in semiconductor fabrication and can be measured in various ways, such as using optical techniques. Bending of a semiconductor substrate can also be measured or evaluated by obtaining a wafer map. Bending can be quantified using a bending value or warpage value, which is measured as the vertical distance between the lowest point of the semiconductor substrate and the highest point on the substrate. The warpage value can be along an axis. For example, a substrate with asymmetric warpage may have warpage along both the x-axis and the y-axis.

[0026] Different types of curvature exist. In an arc-shaped substrate, the lowest point is at the center of the substrate, and the highest point is at the edge. In a dome-shaped substrate, the lowest point is at the edge, and the highest point is at the center. Arc-shaped and dome-shaped substrates have symmetrical or uniform curvature. Substrates can also have asymmetrical curvature. In asymmetrical curvature, warp is measured along the x-axis and y-axis. For x-axis warp and y-axis warp, asymmetrically curved substrates have different values. In some cases, asymmetrically curved substrates have negative x-axis warp and positive y-axis warp. In some cases, asymmetrically curved substrates have positive x-axis warp and negative y-axis warp. In some cases, asymmetrically curved substrates have positive x-axis warp and positive y-axis warp, but the warp values ​​are different. In some cases, asymmetrically curved substrates have negative x-axis warp and negative y-axis warp, but the warp values ​​are different. An example of an asymmetrically curved substrate is a saddle-shaped substrate. For a saddle-shaped substrate, in one example, the warpage along the x-axis can be 200 µm, while the warpage along the y-axis can be -200 µm. The saddle-shaped substrate has two opposing substrate edges that curve upwards, while two other opposing substrate edges curve downwards.

[0027] Bending can cause problems for subsequent processing, such as during photolithography, because etching may be uneven if the semiconductor substrate warps. Another potential problem is that if the bending is too large, the substrate may not be properly clamped. High bending can be caused by, for example, the deposition of a thick, high-stress carbon hard mask layer. Furthermore, due to the multilayer stacked films and the presence of a thick, high-stress carbon-based hard mask for this process, etching may cause some asymmetric warpage, and the deposition process may introduce bending as high as [insert value here]. Significant substrate warpage occurs with a bending variation ranging from 500µm to -1300µm. For example, ashingable hard masks can have stresses up to -1000MPa and introduce bending values ​​up to -1000µm. Addressing this substrate warpage can be challenging because subsequent processing can be affected by warpage exceeding +500µm, and can pose a particular challenge, especially when the substrate is used in subsequent processes involving clamping the substrate in an electrostatic chuck, as many electrostatic chucks have a “clamping limit” (defined as the maximum allowable warpage before the substrate cannot be effectively clamped). Many electrostatic chucks have approximately The clamping limit is 300µm. Therefore, highly warped semiconductor substrates may not be processed in some tools. Furthermore, processing highly warped semiconductor substrates may cause further warping. For example, due to asymmetric stress on the semiconductor substrate, etching trenches in a single direction may cause warping in terms of asymmetric bending.

[0028] The semiconductor industry has adopted intentional back-side film deposition to compensate for wafer warping caused by high-stress front-side films. Various methods can be used. As an example, plasma-enhanced chemical vapor deposition (PECVD) can be used to deposit films across the entire back side of a substrate. An alternative exemplary method used in this industry utilizes back-side films deposited via physical vapor deposition (PVD).

[0029] Generally, back-side deposition forms a dielectric film on the back side of a substrate or wafer. Figure 1A is an exemplary cross-sectional view of a semiconductor substrate 102 (e.g., a wafer) having a front-side layer 108 and a back-side layer 110. If the internal stress of the back-side layer 110 is opposite in magnitude to and comparable in magnitude to the internal stress generated on the front side, the back-side film effectively counteracts and corrects bending. Typical examples may include the following: 1. Deposit one or more front layers with high internal stress (e.g., in chamber A), which produce significant bending.

[0030] 2. Deposit a back-side layer with internal stress (e.g., in chamber B), which counteracts the internal stress of one or more front-side layers and reduces or eliminates bending.

[0031] 3. Pattern the front side of the unbent substrate using photolithography.

[0032] 4. Etch an unbent, patterned substrate (e.g., chamber C).

[0033] Rooms A, B, and C can be different, but this is not always the case. For example, in some implementations, rooms A and C are the same.

[0034] The above method is acceptable for achieving uniform bending, but a growing area of ​​interest is compensating for the bending of saddle-shaped semiconductor substrates, as few techniques exist for compensating for asymmetric warpage (e.g., saddle-shaped bending). Applying a uniform back-side layer (where the bending compensation effect is the same everywhere on the substrate) to a saddle-shaped substrate will not produce a flat substrate. Due to the different amounts of bending along different axes, parts of the substrate will retain warpage after uniform bending compensation. More cost-effective and flexible improved methods for compensating for saddle-shaped bending are desired.

[0035] According to certain embodiments of this disclosure, such an improved method can utilize so-called atmospheric pressure plasma jet (APPJ) technology to produce a non-uniform back-side layer. This technology, in some embodiments, may involve operating one or more nozzles under atmospheric conditions to provide a pressurized jet of plasma radicals toward a semiconductor substrate. Details of the components of a system using APPJ will be discussed with reference to Figures 2, 2A, 2B, and 3. Such a non-uniform back-side layer can have varying bending strength on the back-side surface of the substrate, and the bending compensation effect can vary in the azimuth and / or radial directions. APPJ can be extended to formulation-controlled, back-side deposition applications. In APPJ hardware, the substrate can be rotated on near-atmospheric pressure alignment hardware and passed through a controlled plasma jet region. Plasma jets can be used to produce the non-uniformity of the back-side layer, selectively depositing and / or etching the back-side layer material at different locations on the back side of the substrate. Plasma chemicals can etch areas near the substrate edges (or other portions of the substrate). Alternatively, selecting a suitable plasma feed gas can induce plasma-enhanced chemical vapor deposition of the material, rather than etching. In some embodiments of this disclosure, a pie-shaped jet, which may consist of a single jet region or an array of jets, may be used instead of a single jet. In some implementations, such an array may be as simple as a plurality of jets distributed along the radius of the substrate.

[0036] The resulting bend compensation effect is shown in Figures 1B and 1C. Figure 1B shows a simplified cross-sectional view of substrate 102 without any bend. Substrate 102 may be associated with a mid-plane (or average mid-plane) 120, which may be a plane passing through substrate 102 at the midpoint distance between the highest and lowest points of the substrate. In Figure 1B, mid-plane 120 passes through substrate 102 in such a way that it divides substrate 102 into two symmetrical halves in the vertical direction. Figure 1C shows a simplified cross-sectional view of substrate 102' with bend. Obviously, substrate 102' is depicted as slightly bend, and for illustrative purposes, it may be exaggerated or not to scale. Internal stresses from such prior treatment may cause bend, and it is desirable to mitigate this bend. Such bend may already be a result of prior treatment, such as front-side deposition or unintentional or unintended back-side deposition. A curved substrate 102' may be associated with a mid-plane (or average mid-plane) 120' that does not pass through the exact center of the substrate 102.

[0037] One advantage of using APPJ is that, although substrate rotation may be rapid (e.g., a rotation rate of 60-120 revolutions per minute), the modulated RF (radio frequency) power of the plasma jet can be achieved much faster. Synchronization of power with substrate angle or substrate position can produce regions with a variety of film properties to adjust the net substrate shape to a desired, nominally flat (or at least relatively flat) profile, thereby mitigating bending. Between these two broad variables, a direct-write process can be implemented, where, for saddle-shaped substrates, different properties can be deposited, for example, in alternating quadrants (even quadrants versus odd quadrants). Two exemplary film properties to be modulated include film thickness and stress.

[0038] Therefore, the disclosed concept offers the following benefits: direct writing capability for high process tunability; extremely high yield due to extremely high deposition rates at near atmospheric pressure; significantly reduced cost; easy integration with deposition or etching tools; and a greatly reduced product footprint if implemented alone.

[0039] Atmospheric pressure plasma jet system According to some embodiments, Figure 2 shows a simplified block diagram of a system 200 configured to provide a pressurized jet of plasma radicals toward the back side of a semiconductor substrate 201. In some embodiments, system 200 may include a single nozzle 230, which is at least partially housed within a nozzle housing 220 of assembly 205, which integrates other components 225 with the nozzle housing 220. In some embodiments, the nozzle housing 220 may extend to include more than one nozzle (e.g., up to 5 to 10 nozzles). In this case, each of the multiple nozzles is capable of etching or deposition; for example, a first nozzle may be used for deposition while a second nozzle may be used for etching. Typically, all nozzles will provide etchant, or all nozzles will provide deposition precursors. System 200 can operate under atmospheric conditions. System 200, including nozzle 230, allows for minimal hardware changes while significantly improving the deposition or etching rate with respect to substrate 201.

[0040] In some embodiments, a radio frequency (RF) power source may be coupled to the nozzle 230 to provide RF power to electrodes (e.g., a first electrode and a second electrode), which may be housed within the nozzle 230 or nozzle housing 220. The RF power source and / or one or more gas sources (e.g., a first gas source and a second gas source) may be connected via wires and / or gas lines to components of the nozzle housing 220, the nozzle 230, and / or assembly 205, or components of the nozzle housing 220 (e.g., electrodes). In some implementations, the RF power source may be coupled to the nozzle 230 and configured to provide RF power to generate a plasma of a first gas (e.g., in a first channel defined between the first and second electrodes, which will be described in more detail below). Specifically, in some applications, the nozzle 230 may emit free radicals of the plasma generated within the nozzle 230 and carried by a second gas (e.g., a carrier gas). The RF power can be used to generate free radicals of the plasma of the first gas in the first channel (to be described in more detail below). Next, these free radicals can be carried out of the first channel through a first opening (i.e., a first outlet) defined at the opening of nozzle 230. A second gas can flow out of the second channel through a second opening (i.e., a second outlet) defined at the opening of nozzle 230. The second opening can be configured adjacent to the first opening such that the second gas flowing out of the second channel surrounds the free radicals of the plasma flowing out of the first opening, generating a pressurized jet of plasma free radicals to increase the deposition or etching rate. The second gas can act as a shield to concentrate the free radicals onto a specific location (e.g., an edge) of the substrate 201 received above nozzle 230. Furthermore, the second gas shield can prevent recombination and other reactions in the air and prevent the diffusion of plasma free radicals.

[0041] As described above, when the substrate 201 is rotated, the RF power can be modulated to alter the emission of plasma radicals, thereby creating, for example, a desired deposition or etching pattern on the back side of the substrate 201. Such modulation can be performed based on signals generated by a controller, logic, differential driver, etc., coupled to the nozzle 230.

[0042] As mentioned or will be mentioned elsewhere in this document, the controller or logic may further control one or any combination of the following parameters: the substrate rotation rate, the nozzle position relative to the substrate (on, for example, the x, y and / or z axes), and deposition rate parameters (e.g., plasma power, plasma frequency, gas flow rate, gas composition, and / or gas pressure).

[0043] Parameters can also affect the deposition method. Such deposition parameters may include: plasma power (on / off; or high / low between high and low RF power, rather than on to off), plasma frequency, gas flow rate, gas composition, gas pressure, and residence time of the nozzle jet emitter at any location on the substrate. Any of these deposition parameters can affect the local thickness and / or internal stress of the backside layer. These parameters can be controlled when the substrate is rotated or when the nozzle 230 is positioned relative to the substrate (including in XYZ space, radially, and in azimuth). In embodiments where multiple nozzles 230 are used or included in the nozzle housing 220, each of the multiple nozzles can be controlled individually.

[0044] In some embodiments, system 200 may also include or be configured to interact with chuck 210. In some embodiments, chuck 210 may include a lever portion and a clamping portion that abuts against substrate 201. The lever portion may be narrow enough (e.g., the diameter of the lever portion is significantly smaller than the diameter of substrate 201, for example, less than half the diameter of the substrate) to accommodate movement of chuck 210 toward nozzle housing 220 such that nozzle 230 can access a large portion of the surface area of ​​the back side of substrate 201. Those skilled in the art will recognize various configurations for securing substrate 201 relative to chuck 210.

[0045] In some embodiments, chuck 210 may be a vacuum chuck. A vacuum chuck can provide sufficient holding force to securely hold the semiconductor wafer 201 (e.g., a wafer). In some embodiments, chuck 210 may be an electrostatic chuck (ESC), which can use electrostatic forces to securely hold the substrate 201. In some cases, such an ESC may be a bipolar ESC having a pair of complementary and coplanar clamping electrodes (which may be embedded within a base structure) that generate electrostatic forces. In some cases, the ESC may be a unipolar ESC having a single clamping electrode, wherein this single electrode may have a voltage applied to it, and opposite charges may be induced in the substrate 201 using, for example, a counter electrode (not shown) above the substrate 201 or plasma generated above the substrate 201.

[0046] In some embodiments, the chuck 210 may be configured to move in multiple degrees of freedom. The chuck 210 may be configured to translate along the x, y, and / or z axes, for example using an actuator, to move the substrate 201 in the corresponding directions. Furthermore, the chuck 210 may be configured to rotate 212 relative to the z-axis to rotate the fixed substrate 201 at the same rotational rate (e.g., 60-120 revolutions per minute). In some embodiments, the chuck 210 may be fixed to a separate stage 214 (or a separate actuator), such as an XYZ stage (not shown), configured to translate (along the x, y, and / or z axes) and / or rotate (relative to the z-axis), or to translate and / or rotate the chuck 210. Rotation about the z-axis allows the nozzle 230 to cover the entire circumference of the substrate 201, and various deposition or etching patterns can be formed by controlling the state of the nozzle 230 (high / low or on / off). As an illustrative example, chuck 210 may be movable along axis 216 toward or away from assembly 205 or nozzle housing 220. While chuck 210 and / or stage 214 in these embodiments are movable units, assembly 205 may be stationary. However, in some embodiments, alternatively or additionally, assembly 205 may be movable in at least one degree of freedom (e.g., along the x-axis, y-axis, and / or z-axis). That is, depending on the embodiment, chuck 210 and at least a portion of assembly 205 may be stationary or movable to bring nozzle 230 onto substrate 201 received on chuck 210. In some embodiments, nozzle housing 220 or nozzle 230 may be configured to rotate, tilt, or angle about the x-axis and / or y-axis such that when substrate 201 is positioned over nozzle 230, nozzle 230 may cover a larger portion of the substrate. In some embodiments, the position of nozzle 230 may be changed relative to nozzle housing 220. For example, nozzle 230 can be along the x-axis, y-axis, z-axis, radial (r) direction, and / or angle ( The nozzle 230 is repositioned in the direction of the nozzle housing 220. Angular repositioning can tilt the nozzle 230 relative to the nozzle housing 220, but the nozzle housing 220 can remain in the same angular position or tilt angle.

[0047] In some exemplary operations, a chuck 210 having a substrate 201 received thereon may be moved along the x-axis and / or y-axis (e.g., via signals from a controller (not shown)) to bring the edge or inner portion of the substrate 201 above the nozzle 230 of the nozzle housing 220. In some implementations, assembly 205 may also include a second housing 240 or other structure opposite the nozzle housing 220. In some implementations, the second housing 240 may be stationary. In some implementations, the second housing 240 may be movable, for example, along the z-axis. A gap 235 may thus be created between the nozzle housing 220 and the second housing 240 to accommodate and receive a portion of the substrate 201. The size of this gap 235 may be defined such that a portion of the substrate 201, when received in the gap 235, does not contact any surface of the nozzle housing 220 or the second housing 240 of assembly 205, thereby allowing the substrate 201 to rotate freely 212 to expose different portions of the substrate edge or inner portion of the substrate 201 to concentrated plasma free radicals. In some implementations, during operation, the gap 235 between the nozzle housing 220 and the second housing 240 may be defined as being between about 0.8 mm and about 2 mm. In some embodiments, the gap 235 may be defined as smaller, such as about 0.1, 0.2, 0.3 mm or larger, but less than about 0.8 mm. In any case, the gap 235 may be set or adjusted (e.g., via z-axis movement of the nozzle housing 220 or the second housing 240) such that even curved substrates (e.g., 102' of FIG. 1C) can be received without contacting the surfaces of the nozzle housing 220 or the second housing 240. In some embodiments, the nozzle housing 220 and / or the second housing 240 may be coupled to the sidewalls and / or bottom of the processing chamber associated with the system 200. In some implementations, a portion of each of the nozzle housing 220 and / or the second housing 240 may be attached to the sidewall of the processing chamber of the system 200, and the remaining portions of the nozzle housing 220 and / or the second housing 240 may be designed to move along the x-axis, y-axis, and / or z-axis, such that the nozzle housing 220 and the nozzle 230 can be moved to a desired position to position the nozzle 230 below the substrate 201.

[0048] In some implementations, the plasma jet or plasma jet emitter of nozzle 230 may be rasterized above the surface of substrate 201. Rasterization may be performed on multiple nozzles 230 (e.g., an array or group of 2-10 nozzles or plasma jets). In some variations, multiple nozzles 230 may be located in fixed positions relative to each other, and in some cases, multiple plasma jet emitters may be configured within a given nozzle.

[0049] In some implementations, system 200 may include a discharge device (not shown) to rapidly remove plasma radicals and residues released from substrate 201 and / or its edges during or after operations performed using system 200 (e.g., edge bevel removal). Rapid removal of residues and radicals ensures that residues do not contaminate the substrate surface and that radicals do not damage any formed devices present on the substrate surface (e.g., on the front side).

[0050] Figure 2A shows an enlarged, vertical cross-sectional view of a nozzle 230 for system 200 in some embodiments. The nozzle 230 may include a first electrode 233 defined approximately at the center of the nozzle 230. A dielectric material 238 may be configured to surround the first electrode 233 such that a first channel 235 is defined between the first electrode 233 and the dielectric material 238. The first channel 235 may be connected to a first gas source (FIG. 2) via a first inlet 231 defined at a first end and to a first opening 242 located at a second end defined adjacent to the top of the nozzle 230. The first channel 235 may be configured to receive a first gas from the first gas source through the first inlet 231. The first gas may be a reactant gas or a gas mixture, such as a deposition or etching precursor and / or an inert gas. For deposition, plasma chemicals may be selected to produce deposition products of plasma-enhanced chemical vapor deposition (PECVD) or plasma-enhanced atomic layer deposition (PEALD). Exemplary precursors for silica deposition include silanes and tetraethoxysilane (TEOS). Furthermore, the deposition gas used for silicon nitrides may include, for example, nitrogen and ammonia. An exemplary precursor for tungsten deposition includes tungsten hexafluoride (WF6). These examples are illustrative and do not exclude other chemicals selected for a particular film composition. In some etching embodiments, plasma chemicals may be selected to generate volatile reaction products with the film to be etched. For example, oxygen radicals may be targeted at carbon (C) or carbon-based films, while fluorine (F) radicals may be selected to remove molybdenum (Mo) or tungsten (W) materials. Suitable reactants may be selected for the metal or material to be etched. The carrier gas may be an inert gas, such as argon or helium. The reactant gas may be used to generate plasma, and the inert gas may be used to carry the plasma radicals of the reactant gas through the first opening 242. A second electrode 234 may be embedded within a dielectric material 238 and surround the first electrode 233. The dielectric material 238 may act as a barrier to the metal surface to prevent arcing and metal contamination when RF power is applied.

[0051] The dielectric material 238 disposed within the nozzle 230 may further define a second channel 236 between the dielectric material 238 and the nozzle outer wall 239. The second channel 236 may be coupled to a second gas source (FIG. 2) via a second inlet 232 defined at a first end to receive a second gas, and a second opening 243 may be defined at a second end, which is defined at the bottom of the nozzle 230. The second opening 243 may be defined adjacent to and surrounding the first opening 242. The second opening 243 may be a single opening or multiple openings surrounding the first opening 242 (two are depicted in FIG. 2A). The second gas may be an inert gas, such as argon or helium. The second channel 236 may create a separate gas path for the second gas, and the second opening 243 in the top of the nozzle 230 may guide the second gas upward without disturbing the plasma radicals flowing through the first opening 242. The second gas exiting the second opening 243 may act as a shield for the plasma radicals mixed with the carrier gas exiting the first opening 242 by surrounding the mixture of plasma radicals and carrier gas.

[0052] Referring again to Figure 2A, in some implementations, the second electrode 234 embedded in the dielectric material 238 may be oriented parallel to the first electrode 233 disposed approximately at the center of the nozzle 230. In some alternative implementations, the second electrode 234 embedded in the dielectric material 238 may be oriented at least partially perpendicular to the first electrode 233. In yet another alternative implementation, the second electrode 234 may be shaped along the contour of the dielectric material 238 and may be oriented parallel to the first electrode 233. Regardless of orientation, the second electrode 234 may be disposed at a predetermined distance from the first electrode 233, wherein the predetermined distance may be determined to generate plasma received in the first gas in the first channel 235. In some implementations, the first electrode 233 may be made of metal. In some embodiments, the first electrode 233 and the second electrode 234 may be made of the same metal. In some embodiments, the first electrode 233 may be made of a different material than the second electrode 234. The material used for the second electrode 234 may be selected to withstand high temperatures. In some methods, the material used for the second electrode 134 may be selected to have a CTE that matches the coefficient of thermal expansion (CTE) of the dielectric material 238 in which the second electrode 234 is internally embedded. In some methods, the first and second electrodes 233, 234 may be made of any of tungsten, molybdenum, iridium, rhenium, or platinum, and the dielectric material 238 may be made of any of aluminum nitride, aluminum oxynitride, silicon nitride, aluminum oxide, or yttrium oxide. In some implementations, the dielectric material 238 and / or the first electrode 233 may be cooled using one or more cooling elements (not shown). In some cases, the cooling elements may be configured in a region adjacent to the second electrode 234.

[0053] In some implementations, the first electrode 233, configured to be adjacent to the center of the nozzle 230, can be coupled to the aforementioned RF power source, and the second electrode 234 can be grounded via a matching network. In some other implementations, the first electrode 233 can be grounded, and the second electrode 234 can be coupled to the RF power source via a matching network. In still other implementations, the first electrode 233 and the second electrode 234 can be coupled to the RF power source via a matching network, and neither the first electrode 233 nor the second electrode 234 can be grounded.

[0054] In some configurations, differential voltages can be applied to the first electrode 233 and the second electrode 234. As an exemplary example, for an input voltage of 2 volts (V), the voltage applied to the first electrode would be +1V, while the voltage applied to the second electrode would be -1V (i.e., each electrode could be supplied with half the input voltage). In some cases, a differential driver (not shown) can be coupled to an RF power source and used to switch the RF power input between the two electrodes (first electrode 233, second electrode 234). In some implementations, the differential driver can be an isolation transformer with a secondary winding for providing the differential voltage.

[0055] In some implementations, the first gas may comprise a mixture of a reactant gas and a carrier gas. In some specific embodiments, the first gas may comprise a mixture of a deposition precursor and a carrier gas, or a mixture of an etchant gas and a carrier gas. Thus, in some cases, the reactant gas may be oxygen, and the carrier gas may be an inert gas such as argon. In other cases, the reactant gas may be oxygen, and the carrier gas may be another inert gas such as helium. It should be noted that the above gas examples are provided only as examples and should not be considered limiting. In the case of system 200 for edge bevel removal, depending on the type of film (i.e., residue) of the edge material to be removed, the carrier gas may be any suitable inert gas (e.g., argon or helium), and the etchant gas may be fluorine, chlorine, or some other halogen, or hydrogen.

[0056] To achieve high-precision etching or deposition, the nozzle 230 can be configured to supply high-density plasma radicals to the substrate 201. In some exemplary embodiments, the flow rate of the reactant gas in the first gas can be defined as between about 100 standard cubic centimeters per minute (sccm) and about 300 sccm, and the flow rate of the carrier gas can be defined as between about 1,000 sccm and about 30,000 sccm.

[0057] The nozzle 230 is constructed to provide an efficient and effective way to process the substrate 201 using a simple processing chamber with minimal hardware. Plasma can be remotely generated and supplied to the edges or other portions of the substrate 201. In addition to the first and second gases applied to the substrate 201, a third gas can also be supplied from a third channel defined adjacent to the nozzle 220. The third gas acts as a gas curtain to push the first gas, which is surrounded by the second gas, away from the center of the substrate, providing concentrated plasma radicals both at the substrate edge and at a defined radius from the center. This simplified design allows the processing chamber to remain lightweight and compact, enabling it to be stacked on top of other existing modules (e.g., load chambers) without occupying additional space.

[0058] In some embodiments, "n" nozzles (where "n" is an integer) may be present within the nozzle housing 220 to simultaneously provide plasma radicals to cover a large area of ​​the substrate 201 or its edges. In some implementations, the nozzle housing may contain 3, 5, 7, or 9 nozzles arranged adjacent to each other. In some implementations, the "n" nozzles may be arranged along an arc defined in the nozzle housing 220. This arc may be defined to match the curvature of the substrate edge. In some implementations, the "n" nozzles may be arranged in a substantially linear manner rather than in an arc that matches the curvature of the substrate edge. In some cases, the linear nozzles may be distributed in a radial direction so that these nozzles can perform deposition or etching at different radial locations along the substrate. While various implementations have been described herein with reference to the system 200 using nozzles, these implementations are not limited to nozzle operation, and other non-nozzle tools or components may also be used to process the substrate 201.

[0059] According to certain embodiments of system 200 of FIG. 2, FIG. 2B shows an exemplary view of plasma radicals with a shielding gas being guided toward the edge 201-e of substrate 201. The shielding gas prevents the plasma radicals from spreading or recombining with the surrounding air, allowing the plasma radicals to be concentratedly applied to the substrate edge 201-e. In the exemplary operation shown, different portions of the substrate edge 201-e may be exposed to plasma radicals as the substrate 201 is rotated 212' about an axis (e.g., the same z-axis that allows chuck 210 to rotate 212). Alternatively or additionally, different portions of the inner portion 201-i of substrate 201 may be exposed to plasma radicals depending on the position (e.g., x, y, and / or z) and / or configuration (e.g., angle) of nozzle 230. In some operations, this configuration may be used to deposit a layer on one or more portions of substrate 201 located on the back side, such as the inner portion 201-i or the substrate edge 201-e, while the substrate is rotated 212'. In some other operations, etching may alternatively be performed on the same area. Nozzle 230 may be tilted toward or away from the central portion of substrate 201. The example shown shows nozzle 230 tilted away, which helps remove edge material and prevents free radicals from accumulating in other portions of the back side of substrate 201. To further assist, in some embodiments, as described above, a third gas received in a third channel 237 defined adjacent to nozzle 230 may be supplied through a third opening located below the surface of substrate 201. In some implementations, the third channel 237 may be located within nozzle housing 220. Sufficient force may be supplied with the third gas to keep plasma free radicals directed toward and process the substrate 201, and to adequately expose substrate 201 to plasma free radicals.

[0060] According to some embodiments, Figure 3 shows a simplified block diagram of another system 300 configured to provide a pressurized jet of plasma radicals toward the back side of a semiconductor substrate 301. Similar to system 200 shown in Figure 2, in some embodiments, system 300 may include a single nozzle 330, which is at least partially housed within a nozzle housing 320 of assembly 305, which integrates other components 325 with the nozzle housing 320. In some embodiments, the nozzle housing 320 may extend to include more than one nozzle. In this case, each of the multiple nozzles can perform etching or deposition; for example, a first nozzle can be used for deposition while a second nozzle can be used for etching. System 300 can operate under atmospheric conditions. System 300, with its combined nozzles 330, allows for minimal hardware changes while simultaneously significantly improving the deposition or etching rate with respect to substrate 301.

[0061] In some embodiments, similar to system 200 shown in FIG2, an RF power source may be coupled to nozzle 330 to provide RF power to electrodes (e.g., a first electrode and a second electrode), which may be housed within nozzle 330 or nozzle housing 320. The RF power source and / or one or more gas sources (e.g., a first gas source and a second gas source) may be connected via wires and / or gas lines to components of nozzle housing 320, nozzle 330, and / or assembly 305, or components of nozzle housing 320 (e.g., electrodes). In some implementations, the RF power source may be coupled to nozzle 330 and used to provide RF power to generate a plasma of a first gas (e.g., in a first channel defined between the first and second electrodes). The RF power can be used to generate free radicals of the plasma of the first gas in the first channel. These free radicals can then be carried out of the first channel through a first opening (i.e., a first outlet) defined at the opening of nozzle 330.

[0062] In system 300, unlike system 200, substrate 301 is stationary (non-rotating) and may be supported by one or more support structures (e.g., annular supports). Each annular support may be fixed to a surface, such as the floor of the processing chamber or another surface. The annular support may be at least partially hollow or connected to other structures or wiring (e.g., to provide air or suction). Various structures other than tubular shapes can be used. In Figure 3, two exemplary annular supports 310a and 310b are partially shown to illustrate how these annular supports contact and hold substrate 301. However, it should be understood that, as shown in Figures 3A and 3B, more annular supports may be used. In some cases, if substrate 301 is partially supported by other structures (e.g., racks extending from the sidewalls of the processing chamber), only one annular support may be used. In some embodiments, substrate 301 may be supported and held stationary by a carrier ring (e.g., a protrusion of the carrier ring).

[0063] In some embodiments, the nozzle housing 320 may be coupled to a stage 314 (or actuator) configured to move in multiple degrees of freedom. For example, the stage 314 may be an XYZ stage capable of lateral movement in the x, y, and z directions, thereby moving the nozzle housing 320 and nozzle 330 to a desired position in (x, y, z) space. As an illustrative example, the nozzle housing 320 may move below the substrate 301 along axis 316. Alternatively or further, the stage 314 may be an R-θ-Z stage capable of using (r, θ, z) space as the primary location for lateral movement, wherein the position of the nozzle 330 or nozzle housing 320 may be determined based on a radius (r) and angle (θ) and height (z) from a reference point. As an illustrative example, the nozzle housing 320 may rotate or swivel 317 about the center of the substrate 301 and below the substrate 301. For example, the nozzle 330 may be directed toward the back side of the substrate 301 along an arc having a curvature substantially similar to that of the edge of the substrate 301.

[0064] In some embodiments of system 300, when the position of the nozzle is changed relative to substrate 301 (e.g., using stage 314), the RF power can be modulated to alter the emission of plasma radicals, thereby creating, for example, a desired deposition or etching pattern on the back side of substrate 301. Such modulation can be performed based on signals generated by controllers, logic, differential drivers, etc., coupled to nozzle 330. The stage 314 can be signaled to laterally move below substrate 301 according to the aforementioned signals, while simultaneously avoiding collisions with support structures such as annular support 310.

[0065] In some implementations, component 305 may also include a second housing 340 or other structures opposite to nozzle housing 320. In some embodiments, the second housing 340 may be stationary. In some implementations, the second housing 340 may be movable, for example, along the z-axis. Similar to that described in FIG2, a gap 335 may therefore be created between nozzle housing 320 and second housing 340 to accommodate and receive a portion of substrate 301.

[0066] In some embodiments, system 300 may include a discharge device (not shown) to rapidly remove plasma radicals and residues released from substrate 301 and / or its edges during or after operations performed using system 300 (e.g., edge bevel removal). Rapid removal of residues and radicals ensures that residues do not contaminate the substrate surface and that radicals do not damage any formed devices present on the substrate surface (e.g., on the front side).

[0067] Figure 3A shows an exemplary cross-sectional view of a substrate 301 that can be processed by system 300. As discussed above, substrate 301 may be stationary and supported by one or more annular supports. The one or more annular supports may be distributed substantially uniformly around the substrate 301. Figure 3A shows three annular supports that are not coplanar.

[0068] For example, as shown in the top view of substrate 301 of FIG. 3A in FIG. 3B, the three annular supports 310a-310c may form a tripod or similar balancing support. It should be understood that such annular supports 310a-310c do not need to be positioned at the edge of substrate 301. One or more of the annular supports 310a-310c may alternatively be positioned away from that edge. In some implementations, at least some of the annular supports 310a-310c may have a vacuum-based mechanism or other mechanism to assist in holding substrate 301. In some implementations, one or more of the annular supports 310a-310c may be replaced by other types of structures (e.g., protrusions of carrier rings).

[0069] Figures 4A-4D are illustrative example patterns of deposition or etching using the APPJ-based system 200. A deposition pattern can be completed by rotating the substrate or wafer at a defined rotational rate (e.g., 60-120 revolutions per minute) and modulating the RF power directed to the plasma jet (e.g., nozzle 230 or 330) to induce deposition or etching at desired locations (e.g., radial locations, angularly defined regions, or lamellae of the substrate). The deposition or etching may form arcuate portions, such as arcuate portions 402a-402d, as illustrated in Figure 4A.

[0070] In other cases, the APPJ-based system 300 can be used alternatively to form the exemplary deposition / etching pattern. For example, rotation of the nozzle housing 320 about the axis of the stage using R-θ-Z functions can form deposition / etching arcuate portions as seen in the exemplary pattern (e.g., 402a-402d), and translation of the nozzle housing 320 using XYZ functions, or tilting of the nozzle 330, can allow deposition / etching of arcuate portions varying in radial position (e.g., 402a to 402b).

[0071] In some implementations, the rotation rate can be constant throughout the deposition or etching process. The RF power directed to the plasma jet (e.g., nozzle 230 or 330) can be modulated in a consistent mode (e.g., high / low or on / off) corresponding to the fixed rotation rate, causing plasma radicals to be emitted toward the back side of the substrate. Advantageously, modulating the RF power while the substrate rotates is an efficient way to perform deposition or etching in a consistent mode because the modulation of the RF power can be done rapidly and the modulation of the RF power and the rotation of the substrate can be synchronized. In exemplary use cases of film deposition, film thickness control is also simplified by increasing the duration of substrate rotation. Furthermore, the radial position of the deposition can be easily controlled using a movable nozzle housing as discussed in Figures 2 and 3.

[0072] However, in some implementations, the rotation rate may vary or be altered depending on processing conditions, user commands, or the radial or angular position of the plasma jet. Changing the rotation rate during the rotation of a single substrate can allow material to be deposited thicker at certain angular locations (where the rotation rate is slower) than at other angular locations.

[0073] Figure 4A illustrates an exemplary pattern of deposition that can be produced by an APPJ-based system 200 (or 300). Based on the rotation of the substrate 401 and the RF modulation of the plasma jet, two general types of regions can be generated on the back side of the substrate 401, for example. Deposition arcs 402a-402d and 404a-404d can be generated in the regions where the deposited layer is deposited, while blank portions 406a and 406b can be left untreated by deposition. The deposition arcs can correspond to when RF power is applied to the plasma jet to emit plasma radicals, while the blank portions 406a and 406b can correspond to when no RF power is applied. In this example, the deposition arcs and blank portions alternate depending on the RF modulation (e.g., high / low or on / off).

[0074] The deposited layer on the back side of substrate 401 can introduce internal stresses that, for example, counteract existing internal stresses (e.g., caused by one or more front layers), thereby compensating for bends present in substrate 401, including asymmetric or non-uniform bends, such as saddle bends. More specifically, varying the thickness of the resulting back-side layer with location (e.g., based on existing bends caused by, for example, front-side deposition or unintentional or unintended back-side deposition), thereby varying the internal stress of the back-side layer with location, can compensate for existing bends in the substrate. The internal stresses (e.g., magnitude and / or orientation) of the resulting back-side layer can vary with location; even a layer of uniform thickness may have different internal stress values ​​at different locations on the substrate. Therefore, the bend compensation effect of the back-side layer can vary with location, wherein the bend compensation effect can be a function of: (i) the back-side layer thickness and (ii) the internal stress of the back-side layer, which is an inherent property of the material forming the back-side layer.

[0075] Etching in the same pattern, as shown in Figure 4A, can be performed similarly using RF modulation of the plasma jet. As an example, etching can remove unwanted deposits on a portion of the substrate located on the back side. In some cases, front-side deposition processes may result in the unintended deposition of material on the back side of the substrate. Such back-side deposits may be undesirable and should be removed before further processing. Using information about the location of the back-side deposited material, the plasma jet can be selectively directed (e.g., along one or more of the arcuate sections shown in Figures 4A-4D) toward the area where the back-side deposited material already exists, thereby etching away that material.

[0076] Figure 4B shows another exemplary pattern of deposition / etching that can be produced by the APPJ-based system 200 (or 300). In this exemplary pattern, deposition or etching may occur near the edge of substrate 401, such as in arcuate portions 412a, 412b. In this exemplary pattern, deposition or etching may occur in different sections of substrate 401 further inward toward the center of substrate 401, such as in arcuate portions 414a-414d.

[0077] Figure 4C shows another exemplary deposition / etching pattern that can be produced by the APPJ-based system 200 (or 300). The arcuate portion may be present near the edge of the substrate 401 and also further inward toward the center of the substrate 401.

[0078] Figure 4D shows another exemplary deposition / etching pattern that can be produced by the APPJ-based system 200 (or 300). Some arcuate portions may be wider, while others may be narrower.

[0079] The exemplary patterns in Figures 4A-4D are purely illustrative and are intended only to depict the RF modulation effect in cases where a substrate is fixed during rotation, as discussed in system 200, or a substrate is fixed at rest, as discussed in system 300. Numerous other patterns (e.g., on the back side of the substrate) may be formed as desired, depending on the bending caused by components or other processes performed (e.g., on the front side of the substrate).

[0080] method According to some embodiments, Figure 5 is a flowchart illustrating a method 500 for depositing a back-side layer on a substrate. The substrate may have a front side having electronic device features fabricated thereon. One or more functions of method 500 may be performed or caused by a computerized device or system. Structures for performing the functions shown in one or more boxes in Figure 5 may include hardware and / or software components of such a computerized device or system, or computing devices, such as controller devices, computerized systems, or computer-readable devices containing storage media storing computer-readable and / or computer-executable instructions configured to cause at least one processor device or computerized device to perform operations when executed by a processor device. A controller may be one example of a computerized device or system or a component thereof. A processing chamber may be another example of a computerized device or system.

[0081] It should also be noted that the operations of method 500 can be performed in any suitable order, not necessarily in the order depicted in Figure 5. Furthermore, method 500 may include additional operations or fewer operations than depicted in Figure 5 to deposit the backside layer.

[0082] In block 510, method 500 may include depositing material at a first location on the back side of a substrate. A portion of the substrate having arcuate portions 402a-402d may be an example of the first location. In some embodiments, the back-side layer at the first location has a first value of certain characteristics, wherein material is deposited at the first location by a plasma jet emitted from a nozzle positioned near the first location. This nozzle may be an example of nozzle 220 or 320. In some embodiments, the nozzle may be one of a plurality of nozzles arranged in an arcuate shape that generally conforms to the curvature of the edge of the substrate. In some embodiments, the plurality of nozzles may be arranged linearly, for example, along a radial direction, so that the plurality of nozzles may deposit (or etch) a layer (or etch material) at different radial locations along the substrate.

[0083] In some embodiments, deposition is performed using an atmospheric pressure plasma jet (APPJ) system (e.g., system 200 or 300 as discussed in Figures 2 or 3). The deposited material may be a product of plasma generated using a nozzle, as discussed in Figures 2 or 3. In some embodiments, the operation of the system and / or nozzle may involve launching a plasma jet associated with the nozzle onto the back side of the substrate at approximately atmospheric pressure. In some embodiments, the operation may involve launching at approximately 0.5 to 1.5 times atmospheric pressure. Depending on the various embodiments, the deposited material may comprise one or more back side layers. The number of one or more layers may be predetermined. This information may affect, for example, the number of rotations required to process at least a first location on the back side of the substrate.

[0084] In some embodiments, this characteristic may include a bending compensation effect of the back-side layer, such as the distance between the edge or center of the substrate and the average midplane of the substrate (e.g., midplane 120' in FIG. 1C), which may be smaller than the distance before bending compensation. In some embodiments, this characteristic may include internal stresses in the material of the back-side layer. In some embodiments, this characteristic may include the thickness of the back-side layer.

[0085] At block 520, method 500 may include moving the nozzle and / or substrate to position the nozzle in a second position near the back side of the substrate. In some embodiments, the substrate is moved by rotation, wherein the substrate is held and held by a chuck. Thus, in some cases, blank portion 406a may be an example of the second position. In some cases, arcuate portions 404a-404d may be an example of the second position. In some implementations, a vacuum chuck may hold the substrate in the center and rotate the substrate at a defined rotational rate (e.g., 60-120 revolutions per minute). This rotation may position the second position of the back side of the substrate above the nozzle, although only for a moment. In some embodiments, the nozzle may face the first and second portions alternately (e.g., from 402a to 406a). As another example, the chuck may translate (e.g., on the x, y, and / or z axes) to position the back side of the substrate above the nozzle at different locations on the back side. For example, the substrate may be moved so that the nozzle changes from a previous position facing 402a to now facing 402b. In some implementations, the nozzle housing (e.g., nozzle housing 220 or 320) can move toward or away from the substrate (translation or rotation). In some embodiments, the substrate and the nozzle can move toward or away from each other, or move different distances in the same direction.

[0086] In block 530, method 500 may include depositing material at the second position as the nozzle approaches the second position, wherein the back-side layer at the second position has a second value for the characteristic, which differs from a first value for the characteristic. In some embodiments, different amounts of deposition may be made between the first and second positions. For example, if the first position adjacent to the nozzle is 402a and the subsequent second position adjacent to the nozzle is 402b, then different amounts of material deposition may be required to reduce bending because different amounts of internal stress may exist at the corresponding positions on the front side of the substrate. As another example, if the first position is 402a and the second position is 406a, then very little deposition may be required at the second position to achieve a bending compensation effect.

[0087] The surface modification described above is not limited to film deposition. In some implementations, the method 500 described above can be used for etching instead of deposition. That is, the etchant can be directed from the nozzle toward the substrate. Etching can provide spatial stress relief by removing unwanted (or undesirable) deposits (e.g., existing films) on a portion of the back side of the substrate, thereby producing a bending compensation effect.

[0088] In alternative implementations, lasers can be used instead of emitting plasma jets through nozzles, where etching may involve laser-excited ablation or true laser etching in a chemical environment, or laser-excited deposition in a chemical environment.

[0089] Device-Computing and Controller Implementation Plan Figure 6 shows a simplified block diagram of an APPJ-based system or apparatus 600 as described herein, which may include a nozzle (or multiple nozzles) 602, an actuator (e.g., a chuck) 604, and a controller 606 (or multiple controllers) coupled to the nozzle, nozzle housing, and / or actuator. Such an apparatus may be configured to implement the method 500 described above using one or more of the aforementioned components 602-606. In some embodiments, operation of the apparatus may involve emitting a plasma jet onto the back side of a substrate at approximately 0.5 to 1.5 times atmospheric pressure (e.g., at approximately atmospheric pressure).

[0090] In some exemplary embodiments, nozzle 602 may be at least partially housed by nozzle housing 603 and may be configured to direct a plasma jet onto the back side of a substrate to deposit material onto the back side of the substrate and form a back side layer containing the material; actuator 604 may be configured to adjustably position the back side of the substrate relative to nozzle 602 during the deposition of the back side layer; and controller 606 may be configured to deposit the material onto the back side of the substrate in such a manner that the formed back side layer has different characteristics varying at different locations on the back side layer (this may, for example, produce the exemplary deposition / etching pattern shown in Figures 4A-4D or other types of patterns).

[0091] In some embodiments, nozzle 602 may be housed in a nozzle housing that may include an inlet line configured to deliver gas and / or plasma from a source to an outlet of nozzle 602. The axis of nozzle 602 may be angled relative to a plane parallel to the substrate, the angle being adjustable between orthogonal and non-orthogonal (tilted). In various configurations, controller 606 may also be configured to adjust one or more processing conditions during operation of the computerized device. Processing conditions may include: the rotational rate of the substrate using actuator 604, the position and / or angle associated with nozzle 602, the plasma power associated with the plasma jet of nozzle 602, the plasma frequency associated with the plasma jet of nozzle 602, the residence time of the plasma jet at a location on the substrate, gas flow rate, gas composition, gas pressure, or any combination thereof. In some cases, controller 606 may be configured to adjust the plasma power during a single rotation of actuator 604 with the substrate. In some cases, the controller 606 may be configured to repeatedly adjust the plasma power (e.g., high / low or on / off) during multiple rotations of the actuator 604 with the substrate.

[0092] In some embodiments, actuator 604 may be configured to rotate the substrate during material deposition (as discussed with respect to system 200 of FIG. 2). Actuator 604 may be configured to translate the substrate relative to the substrate along a plane parallel to the substrate or along a plane orthogonal to the plane parallel to the substrate (e.g., the z-axis), or to move the substrate radially relative to the substrate. Depending on the application, the rotational speed of the substrate may be 60-120 revolutions per minute. In one example, the rotational speed may be about 100 revolutions per minute. Actuator 604 may also be configured to provide gridded deposition of material. Actuator 604 may also be configured to maintain a gap between the substrate and the exit of nozzle 602 during material deposition, wherein the gap is between about 100 and 1000 micrometers (0.1-1 mm).

[0093] In various implementations of the above method 500, the material deposition method may include material deposition at different locations on the back side layer to compensate for substrate curvature. Material deposition at different locations on the back side may include deposition at different angular regions and / or different radial regions of the substrate.

[0094] In some operations, the controller 606 may be configured, for example, to guide the etchant from the nozzle 602 toward the substrate during a second operation.

[0095] This disclosure can be described in the general context of computer code or machine-usable instructions, including computer-executable instructions, such as program modules, that are executed by a computer or other machine (e.g., a personal data assistant or other handheld device). Generally, program modules, including routines, programs, objects, components, data structures, etc., refer to code that performs a specific task or implements a specific abstract data type. This disclosure can be implemented in a variety of system configurations, including handheld devices, consumer electronics, general-purpose computers, more specialized computing devices, etc. This disclosure can also be implemented in distributed computing environments, where tasks are performed by remote processing devices linked via communication networks.

[0096] In some embodiments, a “controller” (e.g., 190) is part of a system that includes various types of sensors as described herein. Such a system includes a processing tool with a camera sensor. This system may include a semiconductor processing apparatus comprising processing tools, chambers, processing platforms, and / or specific processing components (substrate pedestals, gas flow systems, etc.). These systems may be integrated with electronics to control their operation before, during, and after processing a semiconductor substrate or wafer. The controller may be implemented using, or coupled to, the analytical logic described above. The controller may be implemented as logic, such as electronics having one or more integrated circuits, memory devices, and / or software, to receive instructions, issue instructions, control operations, and / or perform sensing operations.

[0097] An electronic device may be referred to as a “controller”, which controls various components or sub-components of one or more systems. Depending on the processing requirements and / or system type, the controller may be programmed to control any process disclosed herein, including the delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings in some systems, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, substrate transfer tools and other transfer tools, and / or loading locks that are connected to or docked with a specific system.

[0098] In a broad sense, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software for receiving instructions, issuing instructions, controlling operations, enabling cleaning operations, enabling endpoint measurements, etc. Integrated circuits can include chips in the form of firmware storing program instructions, digital signal processors (DSPs), chips defined as application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). Program instructions can be instructions sent to the controller in the form of various individual settings (or program files), which define operating parameters for performing a specific process on or for a semiconductor substrate or system. In some embodiments, operating parameters can be part of a recipe defined by a process engineer to complete one or more processing steps during the processing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0099] The controller can be configured to control or cause various components or sub-components of the control system. Depending on the processing requirements and / or system type, the controller can be programmed to control any processing that can be used by the processing tool during the processing operation, including adjusting or maintaining the delivery of processing gases, temperature settings including substrate temperature and chamber wall temperature (e.g., heating and / or cooling), pressure settings including vacuum settings, plasma settings, RF matching circuit settings, and substrate positioning and operation settings, including substrate transfer into and out of the processing tool and / or loading lock. Processing gas parameters include processing gas composition, flow rate, temperature, and / or pressure. Particularly relevant to the disclosed embodiments, controller parameters may relate to plasma generator power, pulse rate, and / or RF frequency.

[0100] Process parameters under the control of the controller can be provided in the form of a recipe and can be input via a user interface. Signals for monitoring the process can be provided through analog and / or digital input connections of the system controller. Signals for controlling the process are output through analog and digital output connections of the deposition unit.

[0101] In one example, instructions for igniting or sustaining the plasma are provided in the form of process recipes. Related process recipes may be arranged sequentially such that at least some instructions for the process can be executed simultaneously. In some implementations, instructions for setting one or more plasma parameters may be included in a recipe prior to the plasma ignition process. For example, a first recipe may include instructions for a first time delay, instructions for setting the flow rate of an inert gas (e.g., helium) and / or reactant gas, and instructions for setting the plasma generator to a first power setpoint. A subsequent second recipe may include instructions for a second time delay and instructions for supplying power to the plasma generator under a defined set of parameters. A third recipe may include instructions for a third time delay and instructions for deactivating the plasma generator. It should be understood that these recipes may be further subdivided and / or repeated in any suitable manner within the scope of this disclosure. In some deposition processes, the duration of plasma triggering may correspond to a duration of several seconds, for example from about 3 seconds to about 15 seconds, or may involve a longer duration, such as a duration of up to about 30 seconds. In some implementations described herein, shorter plasma triggering can be performed during the processing cycle. Such plasma triggering durations can be on the order of less than about 50 milliseconds, with about 25 milliseconds used in a specific example. As mentioned above, plasma can be generated in a pulsed manner.

[0102] In some embodiments, the controller is configured to control and / or manage the operation of the RF signal generator. In some embodiments, the controller is configured to determine an upper and / or lower threshold for the RF signal power to be transmitted to the machining tool, determine the actual (e.g., real-time) level of the RF signal power transmitted to the integrated circuit machining chamber, the RF signal power start / stop time, the RF signal modulation duration (for example, high / low or on / off states), duty cycle, operating frequency, etc.

[0103] As a further example, the controller may be configured to control the timing of various operations, gas mixing, pressure in the processing tool, temperature in the processing tool, temperature of the substrate or base, positioning of the base, chuck and / or pedestal, and several cycles performed on one or more substrates.

[0104] The controller may include one or more programs or routines for controlling designed subsystems associated with the processing tool. Examples of such programs or routines include substrate positioning programs, process gas control programs, pressure control programs, heater control programs, and plasma control programs. The substrate positioning program may include program coding for processing tool components used to load the substrate onto a pedestal and control the spacing between the substrate and other parts of the processing tool. The positioning program may include instructions for moving the substrate into and out of the reaction chamber to deposit a film on the substrate and for cleaning the chamber.

[0105] The process gas control program may include code for controlling the gas composition and flow rate, and code for stabilizing the pressure in one or more processing stations by allowing gas to flow into them prior to deposition. In some implementations, the process gas control program includes instructions for introducing gas during film formation on the substrate in the reaction chamber. This may include introducing gas at different cycle numbers for one or more substrates within a batch of substrates. The pressure control program may include code for controlling the pressure in the processing station by adjusting, for example, throttle valves in the processing station's exhaust system, the gas flow into the processing station, etc. The pressure control program may include instructions for maintaining the same pressure during deposition at different cycle numbers on one or more substrates during batch processing.

[0106] The heater control program may contain code for controlling the current supplied to the heating element, which is used to heat the substrate. Alternatively, the heater control program may control the delivery of a heat transfer gas (e.g., helium) to the substrate.

[0107] In some implementations, a user interface may be associated with the controller. The user interface may include a display screen, a graphical software display of the device and / or processing conditions, and user input devices such as pointing devices, keyboards, touch screens, microphones, etc.

[0108] In some implementations, the controller may be part of or coupled to a computer integrated with, coupled to, or otherwise networked to the system, or a combination thereof. For example, the controller may be in the “cloud” or be all or part of a fab host system, allowing remote access to substrate processing. The computer may enable remote access to the system to monitor the current progress of processing operations, examine the history of past processing operations, examine trends or performance criteria of multiple processing operations, change parameters of the current processing, set processing steps to follow the current processing, or start a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the system via a network (which may include a local network or the Internet). The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data specifying parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool to which the controller is configured to interface with or control the tool. Therefore, as described above, a controller can be distributed, for example, by comprising one or more discrete controllers networked together and operating toward a common purpose (such as the process and control described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on-site communicating with one or more integrated circuits remotely (e.g., at the platform level or as part of a remote computer), which together control the process on-site.

[0109] Exemplary systems may include, but are not limited to, plasma etching chambers or modules, deposition chambers or modules, rotary rinsing chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfering edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing systems that may be associated with or used for the processing and / or preparation of semiconductor wafers.

[0110] System software can be organized in many different ways and can have different architectures. For example, according to the disclosed implementation, various chamber component subroutines or control objects can be written to control the operation of the chamber components required to perform deposition processes (and in some cases other processes).

[0111] As described above, depending on one or more processing steps to be performed by the tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the plant, a host computer, another controller, or tools used in the transport of materials to and from the tool location and / or loading port in the semiconductor manufacturing plant.

[0112] It will be readily apparent to those skilled in the art that various modifications to the implementations described herein can be made, and that the general principles defined herein can be applied to other implementations without departing from the spirit or scope of this disclosure. Therefore, the claims are not intended to be limited to the implementations shown herein, but should be accorded the widest scope consistent with this disclosure, the principles and novel features disclosed herein.

[0113] Certain features described in the context of individual implementations in this specification may also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation may also be implemented individually or in any suitable sub-combination in multiple implementations. Furthermore, while features may be described above as functioning in certain combinations, or even initially claimed to be so, in some cases one or more features in the claimed combination may be removed from that combination, and the claimed combination may involve sub-combinations or variations thereof.

[0114] Similarly, although operations are depicted in a specific order in the figures, this should not be construed as requiring such operations to be performed in the specific or sequential order shown, or to perform all shown operations to achieve the desired result. Furthermore, the figures may schematically depict one or more exemplary processes in the form of flowcharts. However, other operations not depicted may be incorporated into the schematically shown exemplary processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the shown operations. In some cases, multitasking and parallel processing may be advantageous. Furthermore, the separation of various system components in the above implementations should not be construed as requiring such separation in all embodiments, and it should be understood that the program components and systems may generally be integrated into a single software product or packaged into multiple software products. Additionally, other implementations fall within the scope of the following claims. In some cases, the actions recited in the claims may be performed in a different order and still achieve the desired result.

Claims

1. An apparatus for surface modification of the back side of a substrate, the substrate having a front side having electronic device features processed thereon, the apparatus comprising: A nozzle is configured to direct a plasma jet onto the back side of the substrate, thereby depositing material on the back side of the substrate and forming a back side layer containing the material; An actuator is configured to adjustably position the back side of the substrate relative to the nozzle during the deposition of the material; as well as A controller is configured to cause the plasma jet to deposit the material on the back side of the substrate in such a manner that the formed back side layer has different properties that vary at different locations on the back side layer.

2. The apparatus of claim 1, wherein the method of depositing the material on the back side comprises depositing the material at the different locations on the back side to compensate for the curvature of the substrate.

3. The apparatus of claim 2, wherein depositing the material at different locations on the back side includes depositing at different angularly defined regions on the back side of the substrate and depositing at different radially defined regions on the back side of the substrate.

4. The apparatus of claim 1, wherein the characteristic comprises the bending compensation effect of the back side layer, the thickness of the back side layer, the internal stress of the material on the back side layer, or a combination thereof.

5. The apparatus of claim 1, wherein the controller is further configured to adjust one or more processing conditions, said one or more processing conditions including: The rotational speed of the substrate using the actuator; The position and / or angle associated with the nozzle; The plasma power associated with the plasma jet; The plasma frequency associated with the plasma jet; The residence time of the plasma jet at a certain position on the substrate; Gas flow rate; Gas composition; Gas pressure; or Any combination thereof.

6. The apparatus of claim 1, wherein the actuator is further configured to rotate the substrate during the deposition of the material.

7. The apparatus of claim 6, wherein the substrate rotates at a speed of about 60 to 120 revolutions per minute.

8. The apparatus of claim 6, wherein the controller is further configured to adjust the plasma power during a single rotation of the actuator and the substrate.

9. The apparatus of claim 1, wherein the actuator is further configured to translate the substrate relative to the substrate along a plane parallel to the substrate.

10. The apparatus of claim 9, wherein the actuator is further configured to move the substrate radially relative to the substrate.

11. The apparatus of claim 9, wherein the actuator is further configured to provide gridded deposition of the material.

12. The apparatus of claim 1, wherein the axis of the nozzle is at an angle relative to a plane parallel to the substrate, the angle being adjustable between orthogonal and non-orthogonal.

13. The apparatus of claim 1, wherein the apparatus further comprises an inlet line configured to deliver gas and / or plasma from the source to the outlet of the nozzle.

14. The apparatus of claim 1, wherein the actuator is configured to maintain a gap between the substrate and the nozzle outlet during the deposition of the material, and wherein the gap is between about 100 micrometers and 1000 micrometers.

15. The apparatus of claim 1, wherein the deposition of the material comprises emitting the plasma jet onto the back side of the substrate at a pressure of about 0.5 to 1.5 times atmospheric pressure.

16. The apparatus of claim 1, wherein the controller is configured to, during a first operation, cause the plasma jet to deposit the material on the back side of the substrate, and during a second operation, guide etchant from the nozzle toward the substrate.

17. A method of depositing a back-side layer on a substrate having a front side having electronic device features processed thereon, the method comprising: Material is deposited at a first location on the back side of the substrate, wherein the back side layer contains the material, wherein the back side layer at the first location has a first value of a characteristic, wherein the material is deposited at the first location on the back side of the substrate by a plasma jet emitted from a nozzle located near the first location; Move the nozzle and / or the substrate to position the nozzle in a second position close to the back side of the substrate; as well as When the nozzle is near the second position, the material is deposited at the second position on the back side of the substrate, wherein the back side layer at the second position has a second value of the property, the second value of the property being different from the first value of the property.

18. The method of claim 17, wherein the characteristic is the bending compensation effect of the back side layer, the thickness of the back side layer, the internal stress of the material on the back side layer, or a combination thereof.

19. The method of claim 17, wherein: The first location includes a first angularly defined region on the back side of the substrate, a first radially defined position on the back side of the substrate, or a combination thereof; and The second position includes a second angular defining region on the back side of the substrate, a second radial defining position on the back side of the substrate, or a combination thereof, wherein the second angular defining region is different from the first angular defining region, and the second radial defining position is different from the first angular defining region.

20. The method of claim 17, further comprising rotating the substrate; wherein: While rotating the substrate, the material is deposited at the first location by the plasma jet emitted from the nozzle; and As the substrate is rotated, the material is deposited at the second location by the plasma jet emitted from the nozzle.

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