Frequency and amplitude modulation of implant dose for stress management

Abstract

Embodiments of the present disclosure relate to techniques and apparatus for reducing out-of-plane distortion (OPD) in a substrate, as well as controlling the effects of the OPD and modifying the substrate to correct for the effects of the OPD on subsequent substrate processing operations performed on the substrate. According to the embodiment of the invention, the OPD in the substrate is reduced by adopting a novel technology, and a substrate part which is about to generate problems in a subsequent substrate manufacturing process does not need to be added or modified.

Description

Technical Field

[0001] The present disclosure relates generally to stress control in substrates, and more particularly to stress compensation that reduces out-of-plane distortion in substrates.

[0002] Description of the Prior Art

[0003] Memory devices are essential components in digital electronic devices being developed today. As today's technology advances, most electronic devices require increased memory capacity. At the same time, smaller memory devices are also required to meet the market's demand for manufacturing smaller electronic devices in which memory devices are located.

[0004] In recent years, conventional (2D) NAND memory devices have encountered many challenges, including problems related to voltage drop (e.g., depletion of electrons in current-carrying elements due to the continuous scaling of cell size), retention loss, and overall reliability. To address these challenges encountered when scaling planar (2D) NAND memory devices to achieve higher density at a lower cost per bit, ultra-high density, three-dimensional (3D) stacked memory structures have been introduced. Such 3D memory structures are sometimes referred to as having a Bit Cost Scalable (BiCS) architecture and include vertically integrated strings of memory cells. Typically, the vertically aligned memory cells are formed by an array of alternating conductor layers and insulator layers, where the conductive layers correspond to the word lines of the memory structure.

[0005] As the number of vertically stacked memory cells in 3D NAND devices increases (e.g., as chip density increases), the stress generated within the stacked memory cells increases, which increases substrate bowing and introduces a number of performance issues. Local variations in material composition in vertically stacked memory cells may induce stresses that deform or warp the semiconductor substrate on which the structure is formed. Substrate flatness or curvature has a very large impact on semiconductor device manufacturing because it affects the ability of the lithography system to effectively form device patterns on the substrate surface. Even moderate changes in surface topography within the lithography exposure area can change the device feature pattern or affect the coverage between subsequent layers. This will ultimately lead to potential die yield loss. In order to accurately form device patterns, it is important to form the pattern on the substrate while the substrate remains relatively flat or flat. Substrate bowing is also important for other related manufacturing processes because deformation or warping of the substrate may also cause difficulties in subsequent processing steps, which may include chip bonding or packaging.

[0006] A common concern in fabricating such devices and structures on substrates is the generation of in-plane distortion (IPD), which affects the overlay of a layer relative to an underlying reference layer. IPD is a complex quantity that is affected by the out-of-plane distortion (OPD) of the substrate and the alignment scheme employed in lithography. Wafer processing may produce complex OPD patterns on the substrate at any given processing stage, which may tend to affect subsequent processing operations. For example, a semiconductor substrate may be patterned into a regular array of die regions corresponding to die to be cut from the semiconductor wafer. In a particular example, the complex pattern of OPD may produce overlay errors in subsequent lithography mask operations.

[0007] Therefore, there is a need for an improved method and formed structure that can reduce or eliminate the distortions found in substrates. Summary of the invention

[0008] Embodiments of the present disclosure provide a method for changing the shape of a substrate. The method includes: generating an ion beam profile based on a measured shape of an ion beam; resampling the ion beam profile to generate a blur kernel by adjusting the resolution of the ion beam profile to match the resolution of out-of-plane distortion (OPD) data measured on the substrate; calculating curvature data from the OPD data; filtering the curvature data by applying the blur kernel to the curvature data; generating an inverse filter by Fourier transforming the ion beam profile and resampling the Fourier transformed ion beam profile by matching the resolution of the Fourier transformed ion beam profile with the resolution of the curvature data; applying the inverse filter to the filtered curvature data to generate corrected curvature data; and calculating an implant dose map based on an empirically generated dose sensitivity curve and the corrected curvature data.

[0009] Embodiments of the present disclosure also provide a method for changing the deformed shape of a substrate. The method includes: receiving out-of-plane distortion (OPD) data of the back surface of the substrate; calculating an implantation dose profile to be delivered to the back surface of the substrate, including generating an ion beam profile based on the measured shape of the ion beam, resampling the ion beam profile to generate a blur kernel by adjusting the resolution of the ion beam profile to match the resolution of the out-of-plane distortion (OPD) data measured on the substrate, calculating curvature data from the OPD data, filtering the curvature data by applying the blur kernel to the curvature data, generating an inverse filter by Fourier transforming the ion beam profile and resampling the Fourier transformed ion beam profile by matching the resolution of the Fourier transformed ion beam profile with the resolution of the curvature data, applying the inverse filter to the filtered curvature data to generate corrected curvature data, and calculating the implantation dose profile based on an empirically generated dose sensitivity curve and the corrected curvature data; depositing a distortion correction layer on the back surface of the substrate; and applying the ion beam having the calculated implantation dose profile to the distortion correction layer.

[0010] The embodiment of the present disclosure also provides a substrate containing a semiconductor device. The semiconductor device includes a plurality of semiconductor device layers formed on the front side surface of the substrate, wherein the semiconductor device layers include at least one layer, the at least one layer includes compressive or tensile stress, the compressive or tensile stress generates a deformed shape in the substrate, and the deformed shape includes a varying amplitude at each frequency in a plurality of frequencies; and a distortion correction structure, the distortion correction structure is formed on the back side surface of the substrate and includes a distortion correction layer, the distortion correction layer includes a first material disposed on the back side surface and having a thickness, and an implanted dopant species unevenly distributed on the back side surface of the first material, the first material is disposed on the back side surface of the substrate, wherein the dose of the implanted dopant species is uneven, and the combination of the first material and the implanted dopant species added in the first material is configured to correct the distorted shape formed in the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawings will be provided by the Office upon request and payment of the necessary fee.

[0012] In order to be able to understand in detail the manner in which the above-mentioned features of the present disclosure are achieved, a more specific description of the present disclosure briefly summarized above may be had by reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings illustrate only exemplary embodiments and are therefore not to be considered as limiting the scope of the present disclosure, and other equally effective embodiments may be allowed.

[0013] Figure 1A A substrate including global out-of-plane distortion is shown.

[0014] Figure 1B An example substrate including a more complex out-of-plane distortion is shown.

[0015] Figure 2 A substrate with more complex out-of-plane distortion is shown after a distortion correction layer is added to the back surface of the substrate.

[0016] Figure 3 FIG. 1 shows a diagram of a video image after distortion correction processing has been performed thereon according to one or more embodiments described herein. Figure 2 The substrate shown.

[0017] Figure 4A A method 400 of forming a distortion correction structure is shown according to one or more embodiments described herein.

[0018] Figure 4B A method 450 of determining an implant profile for use with the method 400 to form a distortion correcting structure is shown in accordance with one or more embodiments described herein.

[0019] Figure 5A Out-of-plane distortion (OPD) data for an exemplary substrate is shown.

[0020] Figure 5B Shows the corresponding Figure 5A The power spectral density (PSD) data of the OPD data is shown.

[0021] Figure 5C is a three-dimensional (3D) representation of a Gaussian ion beam according to one or more embodiments described herein, which can be used in one or more methods described herein.

[0022] Figure 5D The invention is shown based on one or more embodiments described herein. Figure 5C The 3D shape of the Gaussian ion beam profile shown is generated by a resampled Gaussian ion beam profile (“blur kernel”).

[0023] Figure 5E The invention is shown based on one or more embodiments described herein. Figure 5D The resampled Gaussian ion beam profile shown produces the Fourier transform of the resampled Gaussian ion beam profile.

[0024] Fig. 5F The invention is shown based on one or more embodiments described herein. Figure 5E The Fourier transform of the resampled Gaussian beam profile produced by the inverse Gaussian filter is shown.

[0025] Figure 5G According to one or more embodiments described herein, one or more methods described herein are applied to Figure 5A Curvature data of an exemplary substrate formed from the OPD data shown.

[0026] Figure 5H Shows the corresponding Figure 5G PSD data for the curvature data shown.

[0027] Fig.5I An empirically generated dose sensitivity curve for a 600 mm wavelength used in one or more methods described herein, according to one or more embodiments described herein, is shown.

[0028] Fig. 6A According to one or more embodiments described herein, one or more methods described herein are applied to Figure 5A Corrected curvature data for an exemplary substrate formed from the OPD data shown.

[0029] Figure 6B Shows the corresponding Fig. 6A PSD data with corrected curvature data shown.

[0030] Figure 6C According to one or more embodiments described herein, one or more methods described herein are applied to Figure 5A Corrected curvature data for an exemplary substrate formed from the OPD data shown.

[0031] Fig.6D Shows the corresponding Figure 6C PSD data with corrected curvature data shown.

[0032] Fig. 6E According to one or more embodiments described herein, one or more methods described herein are applied to Figure 5A Corrected curvature data for an exemplary substrate formed from the OPD data shown.

[0033] Fig. 6F Shows the corresponding Fig. 6E PSD data with corrected curvature data shown.

[0034] Figure 7 In accordance with one or more embodiments described herein, Figure 4A and Figure 4B The method shown is preceded by a method 700 of forming a distortion correction structure for altering overall substrate curvature.

[0035] Figure 8The present invention shows that one or more embodiments described herein have been Figure 7 The distortion correction structure performed on the substrate shown forms part of the process.

[0036] To facilitate understanding, like reference numerals have been used, where possible, to designate like elements in the drawings. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. DETAILED DESCRIPTION

[0037] In the following description, details are set forth in an exemplary manner to facilitate understanding of the disclosed objectives. However, it is apparent to those skilled in the art that the disclosed embodiments are exemplary rather than exhaustive descriptions of all possible embodiments. Therefore, it should be understood that the examples described are not intended to limit the scope of the disclosure. Any changes and further modifications to the described devices, instruments, methods, and any further applications of the principles of the present disclosure are fully contemplated, as would be normally expected by those skilled in the art disclosed. In particular, it is fully conceivable that the features, components, and / or steps described with respect to one embodiment may be combined with the features, components, and / or steps described with respect to other embodiments of the present disclosure. As used herein, the term "approximately" may refer to a variation of + / -10% of the nominal value. It should be understood that such variations may be included in any value provided herein.

[0038] Embodiments described herein relate to techniques and apparatus for correcting complex out-of-plane distortion (OPD) shapes formed in a substrate. The present embodiments employ novel techniques to reduce complex OPD formed in a substrate by generating an implant profile that accounts for amplitude and spatial frequency variations created in a deformed substrate. It has been found that as the amount of spatial frequency variation within a deformed substrate increases, it becomes more difficult to correct for amplitude variations created by higher order spatial frequencies.

[0039] Embodiments of the present disclosure include a distortion correction process that includes depositing a film having a thickness T DCL The distortion correction layer 201 as deposited is then exposed to an implant dose profile configured to account for and correct for complex OPD formed in the substrate.

[0040] As described above, in one application example, as the number of vertically stacked memory cells in a 3D NAND device increases (e.g., as chip density increases), the stress generated within the stacked memory cells increases, which increases the complexity and amount of OPD within the substrate, and thus increases what is often referred to as "wafer bow" or "substrate bow." In order to compensate for the complex substrate distortion shape resulting from spatial frequency variations, an implant dose profile can be developed that separately considers each spatial frequency present in the substrate deformation shape, the deformation shape including, for example, deformation shapes of first, second, third, and fourth order deformation shapes. Therefore, using this technique, the complex OPD formed in the substrate can be corrected by individually applying each individually derived implant dose profile to the just deposited distortion correction layer 201, thereby correcting the complex substrate deformation shape. However, individually applying each individually derived implant dose profile is time consuming and expensive.

[0041] Thus, as described above, the novel techniques disclosed herein are configured to reduce complex OPDs formed in substrates by generating implant dose profiles that account for amplitude and spatial frequency variations produced in deformed substrates.

[0042] Distortion correction structure formation process

[0043] In order to eliminate or minimize complex distortion shapes formed in deformed substrates, a distortion correction structure and a process sequence for forming the structure have been developed and disclosed herein.

[0044] Figure 1A is a side cross-sectional view of a substrate with significant overall substrate curvature resulting from large OPD. Figure 1A The illustrated substrate 101 provides an example of a substrate including a first order deformed shape, so for a 300 millimeter (mm) semiconductor wafer, the illustrated deformed shape has a wavelength (λ) of 600 mm. As another example, Figure 1B is a side cross-sectional view of a substrate including a second order deformed shape, so for a 300 millimeter (mm) semiconductor wafer, the deformed shape shown has a wavelength (λ) of 300 mm. The amount of deflection produced by the OPD can be measured at the center or neutral axis of the substrate 101, as Figure 1A and Figure 1B In one example, the substrate 101 includes a device structure formed on a device side surface 102 of the substrate 101 , and the device structure is used to form a 3D memory device.

[0045] Figure 2 Yes Figure 1B 1 is a side cross-sectional view of the substrate 101 after a distortion correction layer 201 is deposited on the back surface 103 of the substrate 101. The distortion correction layer 201 deposited comprises a thickness T DCL, and is generally formed of a dielectric material. In one example, the just-deposited distortion correction layer 201 includes a silicon nitride (SiN) layer having a thickness less than For example, less than or less than Less than or even less than

[0047] Figure 3 The results were performed on substrates with complex deformed shapes including amplitude and spatial frequency variations. Figures 4A to 4B 1 is a side cross-sectional view of the substrate 101 after the distortion correction structure forming process is shown.

[0048] Figure 4A One embodiment of a distortion correction structure forming process, referred to herein as method 400, is shown for forming a distortion correction structure 202 for compensating for a complex deformed shape found in a substrate 101, according to one or more embodiments described herein. The method 400 begins at activity 402, where OPD data of a complex deformed shape of a backside surface of the substrate 101 is received. The OPD data of the example substrate is shown in FIG. Figure 5A As shown. The OPD data can be measured as a spatial map of displacement in the Z direction of the substrate 101 by using substrate bow measurement techniques. In one example, the OPD data can be measured using WAFERSight TM tool or other similar substrate bow measurement tools to perform the measurement technique. Figure 5B It shows that by Figure 5A The OPD data shown is Fourier transformed into the spatial frequency domain to calculate exemplary power spectral density (PSD) data. The PSD data includes a graph of the OPD power amplitude at various spatial frequencies found in a deformed substrate. x ) and Y direction (i.e., frequency f y ) and the amplitude information at each plotted spatial frequency in the X-Y plot is shown in color, with red representing the maximum amplitude and dark blue representing the lowest amplitude. In this example, the X-axis and Y-axis define the change in spatial frequency of the deformed shape in each measured direction. Higher power spectral density (PSD) plotted on a dB scale includes Figure 5BThe red area near the origin of the graph, and the lower power spectrum frequency density includes the dark blue area farthest from the origin. For reference, the square located at the origin represents a spatial frequency with a wavelength of 600 mm, and the square located at the farthest distance from the origin along each of the X and Y axes represents a spatial frequency with a wavelength of 8 mm (corresponding to a sub-sampled pixel size of 4 mm), it should be noted that this is set by limitations in the measurement technology performed by the bending measurement tool, and is therefore not intended to limit the scope of the disclosure provided herein. Figure 5G shows the curvature of the wafer after various activities performed in method 400, and Fig. 5F The corresponding PSD data is shown.The PSD data shown here is provided only as an example of processing the substrates described herein and is not intended to limit the scope of the disclosure provided herein.

[0049] At activity 404, a system controller (not shown) within one or more distortion correction structure processing tools determines a desired correction amount for correcting amplitude and spatial frequency variations in the deformed substrate resulting from application of a non-uniform implant dose profile. Figure 4B The illustrated method 450 further describes the process of determining a non-uniform implant dose profile implemented in subsequent processing activities. The amount of correction required to be provided by applying the implant profile to the as-deposited distortion correction layer 201 is based on the data collected during activity 402 .

[0050] The system controller described herein may include a central processing unit (CPU) and support circuits operable in conjunction with a memory (e.g., non-volatile memory). The support circuits are coupled to the CPU in a conventional manner and include caches, clock circuits, input / output subsystems, etc., and combinations thereof coupled to various components within one or more distortion correction structure processing tools to facilitate control thereof. The CPU is one of any form of general-purpose computer processor used in an industrial environment to control various components and sub-processors of a processing system. Typically, the memory is in the form of a non-transitory computer-readable storage medium (e.g., non-volatile memory) containing instructions that, when executed by the CPU, facilitate the operation of one or more distortion correction structure processing tools. The computer instructions in the memory are in the form of a program product, such as a program that implements one or more portions of the method of the present disclosure.

[0051] At activity 406, a freshly deposited distortion correction layer 201 is formed on the backside surface of the substrate 101. The process of forming the freshly deposited distortion correction layer 201 may include depositing a dielectric-containing layer on the backside surface 103 using a chemical vapor deposition (CVD) process, a physical vapor deposition (PVD) process, an atomic layer deposition (ALD) process, or other useful deposition processes. In one example, the freshly deposited distortion correction layer 201 may include a silicon nitride (SiN)-containing layer formed by a PVD or CVD process. 3 N 4 ) layer. In some embodiments, the system controller determines the desired thickness T of the just-deposited distortion correction layer 201 based on the data collected during activity 402. DCL .Thickness T DCL The thickness T of the as-deposited distortion correction layer 201 may be selected based on aspects of the implant dose to be provided during activity 308 and thus adjusted based on the implant dose parameters used during activity 408. DCL In some cases, it is desirable to set the thickness of the as-deposited distortion correction layer 201 to be thick enough to ensure that the implanted ions provided during the implantation process performed during activity 408 do not cause the implanted ions to be implanted into the back side of the substrate 101. In some non-limiting examples, the as-deposited distortion correction layer 201 is silicon nitride (Si x N y ) film layer, the silicon nitride (Si x N y ) The film has a thickness T DCL Less than For example, less than or in and between.

[0052] At activity 408, the as-deposited distortion correction layer 201 is exposed to a non-uniform dose of implanted ions based on the non-uniform implant dose profile determined during activity 404, such that the modified as-deposited distortion correction layer 201 (referred to herein as distortion correction layer 203) will correct the complex substrate deformation shape. According to some non-limiting embodiments, suitable implanted ions provided from the ion beam may include any ion species capable of inducing stress changes after implantation at a suitable ion energy, including ions such as phosphorus, boron, argon, nitrogen, krypton, indium, BF 2ions, the ion energy is customized according to the exact ion species used. The dose of implanted ions is applied to the just-deposited distortion correction layer 201 using an ion implantation energy source to correct the complex substrate deformation shape and thereby reduce or minimize the in-plane distortion (IPD) that affects device manufacturing and other device patterning procedures. Non-limiting examples of ion implantation energy sources include ion beams that can be scanned relative to the back surface 103 of the substrate 101. In various embodiments, the ion implantation energy source can transfer non-uniform doses to substrates involving non-uniform direct write processes. In this case, a "direct write" process, including a direct write implantation process, can refer to a process that uses relative movement of an ion beam or other beam for producing an adjustable non-uniform dose, the dose being defined by an implantation profile determined on the substrate surface. In some embodiments, the direct write process can involve exposure to photons, such as a laser beam, and can be used to overall adjust the stress in the just-deposited distortion correction layer 201 to adjust the complex curvature of the substrate, thereby adjusting the OPD of the substrate. In some embodiments, the system controller determines the desired implant process parameters, such as ion energy (keV), dose (atoms / cm 2 ) and / or even atomic species. In some embodiments, method 400 is completed after performing activity 408, so that substrate 101 can then be transferred to one or more subsequent processing steps, such as additional 3D memory device (e.g., 3D NAND device) processing steps. In a non-limiting example, the implantation process includes implanting argon (Ar) atoms into silicon nitride (Si 2 NAND) at a constant energy varying between 50 and 100 keV. x N y ) has just deposited a distortion correction layer having a thickness of about The thickness and 1×10 12 and 1×10 15 Atom / cm 2 between doses.

[0053] Distortion Correction Determination Process

[0054] Figure 4B An embodiment of a process performed during activity 404 is shown, which is referred to herein as method 450. Method 450 begins at activity 452 by generating a Gaussian ion beam profile based on the measurement of the ion beam shape used to deliver the implant dose profile to the desired portion of the substrate surface during activity 408. An example of a Gaussian ion beam profile is shown in FIG. Figure 5C shown.

[0055] At activity 454, the Gaussian ion beam profile generated during activity 452 is resampled such that the resolution of the resampled Gaussian ion beam profile matches the resolution and properties of the OPD data received during activity 402. An example of a resampled Gaussian ion beam profile is Figure 5D As shown. The process of resampling the Gaussian ion beam profile will require correcting various properties of the Gaussian filter generated in activity 454 based on known features of the data provided in the received OPD data. First, curvature data for the wafer is calculated based on the OPD data. Various curvature measures such as Gaussian curvature, average curvature, or X / Y curvature can be used, and the methods described herein can be applied to any of the said curvature measures. The resampled Gaussian ion beam profile (called a "blur kernel") is then applied to the curvature data, as shown. Figure 5G The corresponding PSD data is shown as Figure 5H The application of the blur kernel includes convolution of the curvature data (in the spatial domain) and the blur kernel (in the spatial domain). When convolved with the curvature data received in activity 402, the blur kernel acts as a spatial low pass filter, taking into account the inability of the ion beam to physically address spatial frequencies greater than the limit imposed by the spatial characteristics of the beam itself.

[0056] At activity 456, the Gaussian ion beam profile generated at activity 452 is Fourier transformed into the spatial frequency domain, such as Figure 5E As shown, it is then resampled to match the resolution and properties of the OPD data received during activity 402, as shown Fig. 5F The resampled Fourier transformed Gaussian ion beam profile (referred to as an "inverse Gaussian filter") is then applied to the low-pass filtered curvature data generated in activity 454 (e.g. Figure 5G ), to generate corrected curvature data, such as Fig. 6A The corresponding PSD data is shown as Figure 6B As shown. By means of the filtering process, variations in dose sensitivity to curvature within spatial frequency are taken into account by essentially increasing the spectral amplitude at higher frequencies (i.e., in effect a spatial high pass filter). While the spread of this Gaussian filter is defined by the beam characteristics, its gain is anchored at a fundamental spatial wavelength of 600 mm (corresponding to a wafer diameter of 300 mm) and was determined heuristically by experiment. The filtering process performed in activity 456 essentially constitutes a simple multiplication of the spectrum in the low pass filtered curvature data (in the spatial frequency domain) with an inverse Gaussian filter (in the spatial frequency domain), rather than a convolution of the two data sets, because it is performed in the frequency domain and can therefore replace the computationally expensive step of convolution in the spatial domain. When the Figure 5H The PSD data shown in Figure 6B When comparing the PSD data corresponding to the corrected curvature data shown in , it can be seen that Figure 6B The higher frequencies shown in Figure 5H 456 is further emphasized (i.e., has increased amplitude) at the same frequencies shown in , because, as discussed above, higher frequencies are more difficult to correct due to their greater mechanical stiffness. While not intending to be limited by theory, the process performed during activity 456 is used to amplify the energy in the spectral data at higher spatial frequencies, while also being subject to the constraints imposed by the physical spot size of the ion beam itself, such as Figure 5C Furthermore, the resampling Gaussian filter is tuned to the beam characteristics to account for the fact that the beam cannot physically process spatial frequencies larger than the limit imposed by its own spot size.

[0057] At activity 458 , the system controller calculates an implant dose profile based on the empirically generated dose sensitivity curve and the corrected curvature data such that frequency and amplitude variations found in a warped substrate are accounted for. Fig.5I An empirically generated dose sensitivity curve at a wavelength of 600 mm corresponding to a 300 mm length scale of a silicon wafer is shown, defining the effect of providing increasing amounts of uniform implant dose to the distortion correction layer of the distortion correction structure. Fig.5I The dose sensitivity graph shown was created using a fixed ion energy level applied across the backside surface of substrate 101. At higher spatial frequencies, the dose sensitivity is expected to drop off exponentially, which needs to be accounted for when calculating the dose profile. This is achieved by applying an inverse Gaussian filter to the low pass filtered curvature data.

[0058] Applying the dose sensitivity curve to the corrected curvature data then allows for the generation of an implant dose profile curve, which can then be used in activity 408 as described above. The generated implant dose profile curve allows for adjustment for amplitude variations found within the complex deformed shape of the substrate without the need to separately adjust for spatial frequency variations because the frequency components of the implant dose profile curve have already been accounted for using method 450.

[0059] Figure 6C and Fig.6D The corrected curvature data and corresponding PDS data generated, respectively, have an increased gain level during activity 456 ( Fig. 6A and Figure 6B 5 times the data shown). Fig. 6E and Fig. 6F are the corrected curvature data and corresponding PDS data generated during activity 456, respectively, with an increased gain level ( Fig. 6A and Figure 6B The increased gain is used to further emphasize the lower spatial frequencies in the final implant dose profile curve. By a priori compensating the spectrum, applying the increased gain substantially compensates for the reduced dose sensitivity at higher spatial frequencies.

[0060] Overall substrate bending correction process

[0061] The embodiments described below relate to techniques and apparatus for reducing overall out-of-plane distortion (OPD) in a substrate, as well as controlling the effects of OPD and modifying the substrate to correct for the effects of OPD on subsequent substrate processing operations performed on the substrate. The embodiments of the present case use novel techniques to reduce OPD in a substrate without adding or modifying portions of the substrate that will cause problems in subsequent substrate manufacturing processes. The processes described below can be performed prior to performing the above-described methods 400 and 450, and are therefore used to compensate for overall substrate curvature prior to complex deformed shapes and attempts to remove them by using the above-described methods.

[0062] It has been found that as the thickness of the layer used to compensate for the large overall distortion of the substrate (i.e. Figure 1A ) increases, creating many processing problems in subsequent substrate processing. It has been found that thick stress compensation layers are required to compensate for large overall substrate bending of the substrate, which increases the likelihood of damage or breakage of the substrate in subsequent processing steps. To address the large overall deformations found in the substrate, distortion correction structures and process sequences for forming the structures have been developed and are disclosed below.

[0063] Figure 7 A method 700 is shown for forming a distortion correction structure 802 for compensating for OPD found in a substrate 101 in accordance with one or more embodiments described herein. The method 700 may be performed prior to performing activity 402 of the method 400. In embodiments where the method 700 is performed prior to performing the method 400, the processes performed in activity 406 are not necessary because the distortion correction layer has already been formed during the performance of activity 706 of the method 700. Figure 8 According to one or more embodiments described herein Figure 7 1 is a schematic side cross-sectional view of the substrate 101 during a stage of a method for forming a distortion correction structure 802. In general, the process for forming the distortion correction structure 802 includes depositing a 3D-coated substrate having a thickness T DCL The distortion correction layer 801 is then formed on the back surface 103 ( Figure 1A and Figure 8 ) is exposed to a uniform implantation dose to correct the overall OPD in the substrate 101.

[0064] Method 700 begins at activity 702 where the OPD of substrate 101 is measured using conventional substrate bow measurement techniques. Conventional measurement techniques can be performed using the WaferSight TMTools, metrology systems from MTI Instruments of Albany, NY, or other similar substrate bow measurement tools.

[0065] At activity 704, a system controller (not shown) within one or more distortion correction structure processing tools determines a desired amount of correction required for one or more of the various portions of the distortion correction structure 802 to be formed on the backside surface of the substrate 101. The determined amount of correction required is based on the data collected during activity 702.

[0066] In activity 706, a newly deposited distortion correction layer 801 is formed on the backside surface of the substrate 101. The process of forming the newly deposited distortion correction layer 801 may include depositing a dielectric-containing layer on the backside surface 103 using a chemical vapor deposition (CVD) process, a physical vapor deposition process (PVD), an atomic layer deposition (ALD) process, or other useful deposition processes. The thickness T of the newly deposited distortion correction layer 801 is selected by using the previous activities. DCL , so that it is less than the thickness required to fully compensate for the overall OPD of the substrate 101, and also has a thickness that will ensure that the distortion correction structure 802 will not cause problems in any subsequent manufacturing process, such as a process that requires the use of an electrostatic chuck. In one example, the just-deposited distortion correction layer 801 may include a silicon nitride (Si 2O 2) formed by a CVD process. 3 N 4 ) layer. In some embodiments, the system controller determines the desired thickness T of the deposited distortion correction layer 801 based on the data collected during activity 702. DCL .Thickness T DCL The thickness T of the as-deposited distortion correction layer 801 may be selected based on the profile of the implant dose to be provided during activity 708, and thus adjusted based on the implant dose parameters used during activity 708. DCL In some cases, it is desirable to set the thickness of the as-deposited distortion correction layer 801 to be thick enough to ensure that the implanted atoms provided during the implantation process performed during activity 708 do not cause the implanted atoms to be implanted into the back side of the substrate 101. In some non-limiting examples, the as-deposited distortion correction layer 801 is silicon nitride (Si x N y ) film layer, which has a thickness T DCL Less than For example, less than or in and As described above, in embodiments where method 700 is performed before method 400 , the process performed in activity 406 is unnecessary because a distortion correction layer replacing the just-deposited distortion correction layer 201 has already been formed during performance of activity 706 of method 700 .

[0067] At activity 708, the as-deposited distortion correction layer 801 is exposed to a uniform dose of implanted atoms such that the modified as-deposited distortion correction layer 801 (referred to herein as distortion correction layer 803) will correct the overall OPD. According to some non-limiting embodiments, suitable implanted ions provided from the ion beam may include any ion species capable of inducing a stress change after implantation at a suitable ion energy, including ions such as phosphorus, boron, argon, nitrogen, krypton, indium, BF 2 ions, the ion energy is customized according to the exact ion species used. The dose of implanted ions is applied to the just deposited distortion correction layer 801 using an ion implantation energy source to correct the overall OPD and thereby reduce or minimize the in-plane distortion (IPD) that affects device manufacturing and other device patterning procedures. Non-limiting examples of ion implantation energy sources include ion beams that can be scanned relative to the back surface 103 of the substrate 101. In various embodiments, the ion implantation energy source can transfer the dose to a substrate involving a uniform direct write process. In this case, a "direct write" process, including a direct write implantation process, can refer to a process that uses a relative movement of an ion beam or other beam used to produce a uniform dose on the surface of a substrate. In some embodiments, a direct write process using an ion implantation energy source can involve exposure to electrons, such as an electron beam, or photons, such as a laser beam, which can be used to overall adjust the stress in the just deposited distortion correction layer 801 to adjust the curvature of the substrate, thereby adjusting the OPD of the substrate. In some embodiments, the system controller determines the desired implant process parameters, such as ion energy (keV), dose (atoms / cm 2 ) and / or even atomic species. In some embodiments, method 700 is complete after performing activity 708, so that substrate 101 can then be transferred to one or more subsequent processing steps, such as the processes performed during method 400. In one non-limiting example, the implantation process includes implanting argon (Ar) ions at a constant energy (e.g., 65 keV) into silicon nitride (Si x N y ) is a newly deposited distortion correction layer, the silicon nitride (Si x N y ) The distortion correction layer just deposited has a thickness of about The thickness and 1×10 13 Up to 1×10 14 Atom / cm 2In another non-limiting example, the implantation process includes implanting Ar ions with a constant energy (e.g., 70 keV) with a dose of about Thickness of silicon nitride (Si x N y ) in the freshly deposited distortion correction layer to correct the overall OPD of about 300 μm.

[0068] In one embodiment of activity 708 , as the incoming overall substrate curvature increases, higher implant dopant doses and / or larger implant species are used to correct the curvature, while typically adjusting the implant energy to ensure the total dose remains within the as-deposited distortion correction layer 801 .

[0069] After performing the steps within method 700 , activity 402 of method 400 may then be performed.

[0070] 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 of the present disclosure, and the scope of the present disclosure is determined by the claims which follow.

Claims

1. A method for changing the shape of a substrate, comprising the following steps: generating an ion beam profile based on the measured shape of the ion beam; resampling the ion beam profile to generate a blur kernel by adjusting a resolution of the ion beam profile to match a resolution of out-of-plane distortion (OPD) data measured on the substrate; Calculating curvature data according to the OPD data; filtering the curvature data by applying the blur kernel to the curvature data; generating an inverse filter by Fourier transforming the ion beam profile and resampling the Fourier transformed ion beam profile by matching the resolution of the Fourier transformed ion beam profile to the resolution of the curvature data; applying the inverse filter to the filtered curvature data to produce corrected curvature data; as well as An implant dose map is calculated based on an empirically generated dose sensitivity curve and the corrected curvature data.

2. The method of claim 1, wherein the ion beam profile comprises a Gaussian ion beam profile.

3. The method of claim 2, wherein filtering the curvature data comprises the steps of: The filtering process is used as a low pass filter.

4. The method according to claim 1, further comprising the steps of: Varying amounts of implant dopants are delivered to the backside surface of the substrate based on the calculated implant dose map.

5. The method according to claim 4, further comprising the steps of: A dielectric layer is deposited on the backside surface of the substrate prior to delivering the varying amounts of the implant dopant to the backside surface of the substrate.

6. The method of claim 5, wherein the dielectric layer comprises a layer having a thickness less than of silicon nitride.

7. The method of claim 6, wherein the implanted dopant comprises phosphorus, boron, argon, nitrogen, krypton, indium, or BF2.

8. The method of claim 1, wherein the implant dose map comprises an implant dose profile specifying ion energies and ion doses to be applied to at least two or more regions on the backside surface of the substrate.

9. A method for changing a deformed shape of a substrate, comprising the following steps: receiving out-of-plane distortion (OPD) data of a backside surface of a substrate; Calculating an implant dose profile delivered to the backside surface of the substrate, comprising the steps of: generating an ion beam profile based on the measured shape of the ion beam; resampling the ion beam profile to generate a blur kernel by adjusting a resolution of the ion beam profile to match a resolution of out-of-plane distortion (OPD) data measured on the substrate; Calculating curvature data according to the OPD data; filtering the curvature data by applying the blur kernel to the curvature data; generating an inverse filter by Fourier transforming the ion beam profile and resampling the Fourier transformed ion beam profile by matching the resolution of the Fourier transformed ion beam profile to the resolution of the curvature data; applying the inverse filter to the filtered curvature data to produce corrected curvature data; and calculating an implant dose profile based on an empirically generated dose sensitivity curve and said corrected curvature data; depositing a distortion correction layer on the backside surface of the substrate; and An ion beam having the calculated implant dose profile is applied to the distortion correction layer.

10. The method of claim 9, wherein the distortion correction layer comprises a first material having a compressive or tensile stress when first deposited on the backside surface of the substrate and having a thickness.

11. The method of claim 10, wherein applying the ion beam comprises the steps of: A dopant species is implanted on the surface of the first material deposited on the backside surface of the substrate by exposing the surface of the first material to the ion beam having the calculated implant dose profile scanned over the surface of the first material.

12. The method of claim 11, wherein the calculated implant dose profile includes at least one of ion energy and dose of the ions.

13. The method of claim 11, wherein the dopant species is argon (Ar) or phosphorus (P).

14. The method of claim 11, wherein the frontside surface of the substrate comprises a plurality of semiconductor device layers configured to form at least a portion of a 3D memory device.

15. The method according to claim 9, further comprising the steps of: receiving overall substrate bow measurement information including overall out-of-plane distortion information formed in the substrate including a plurality of semiconductor device layers formed on a front side surface of the substrate; and At least one global distortion correction parameter is determined for use in forming a distortion correction structure formed on the backside surface of the substrate.

16. A substrate containing a semiconductor device, comprising: a plurality of semiconductor device layers formed on a front side surface of a substrate, wherein the semiconductor device layers include at least one layer including a compressive or tensile stress that produces a deformed shape in the substrate, the deformed shape including a varying amplitude at each of a plurality of frequencies; as well as A distortion correction structure, the distortion correction structure is formed on the back side surface of the substrate and includes a distortion correction layer, the distortion correction layer includes: a first material disposed on the back surface and having a thickness; as well as an implanted dopant species, the implanted dopant species being unevenly distributed on a backside surface of the first material, the first material being disposed on the backside surface of the substrate, wherein the dose of the implanted dopant species is non-uniform, and The combination of the first material and the addition of the implanted dopant species within the first material is configured to correct the deformed shape formed in the substrate. 17 . The semiconductor device-containing substrate of claim 16 , wherein the plurality of semiconductor device layers are configured to form at least a portion of a 3D memory device.

18. The semiconductor device-containing substrate of claim 16, wherein the non-uniform dose of the implanted dopant species is defined by an implant dose profile, the implant dose profile being determined by: generating an ion beam profile based on the measured shape of the ion beam; resampling the ion beam profile to generate a blur kernel by adjusting a resolution of the ion beam profile to match a resolution of out-of-plane distortion (OPD) data measured on the substrate; Calculating curvature data according to the OPD data; filtering the curvature data by applying the blur kernel to the curvature data; generating an inverse filter by Fourier transforming the ion beam profile and resampling the Fourier transformed ion beam profile by matching the resolution of the Fourier transformed ion beam profile to the resolution of the curvature data; applying the inverse filter to the filtered curvature data to produce corrected curvature data; as well as The implant dose profile is calculated based on an empirically generated dose sensitivity curve and the corrected curvature data.

19. The semiconductor device-containing substrate according to claim 18, wherein the first material comprises a substrate having a thickness less than of silicon nitride.

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