Magnetic shielding structure for a chip

Abstract

The present disclosure relates to magnetic screen structures for chips. Embodiments of a structure are disclosed that include a chip having embedded magnetic random access memory (eMRAM) or other on-chip components susceptible to performance degradation induced by magnetic fields, and a magnetic screen for protecting the chip. In some embodiments, the magnetic screen includes contiguous magnetic layers having different magnetic properties. In other embodiments, the magnetic screen includes contiguous magnetic layers (of the same or different magnetic materials) having staggered open patterns (e.g., vias or meshes). In any case, the chip can be mounted on a board and housed in a package. Such magnetic screens can be located on the package (opposite the board) and / or on the board (opposite the chip), depending on the expected location of potentially harmful magnetic fields.

Description

Technical Field

[0001] This disclosure relates to a chip, and more specifically to an embodiment of a structure including a chip having embedded magnetic random access memory (eMRAM) or other components susceptible to performance degradation induced by magnetic fields, and a magnetic shield for protecting the chip. Background Technology

[0002] Magnetic random access memory (MRAM) has become a preferred embedded non-volatile memory (NVM) option due to its high speed and stability within the automotive temperature range. Unfortunately, the magnetic immunity of such MARAM can be insufficient in environments with strong magnetic fields. For the purposes of this disclosure, the magnetic immunity of MARAM refers to its ability to resist disturbance by external magnetic fields. One technique for improving the magnetic immunity of MARAM is the use of a magnetic shield. However, currently available magnetic shields for chips typically target narrow magnetic field ranges and can be prohibitively expensive. Summary of the Invention

[0003] This document discloses various embodiments of a protected chip structure. Some embodiments of the structure may include a chip and a magnetic shield adjacent to the chip. The magnetic shield may include at least a first magnetic layer and a second magnetic layer, the second magnetic layer being adjacent to the first magnetic layer and having different magnetic properties from the first magnetic layer.

[0004] Other embodiments of the structure may include a chip and a magnetic shield adjacent to the chip. The magnetic shield may include at least a first magnetic layer and a second magnetic layer adjacent to the first magnetic layer. The first magnetic layer and the second magnetic layer may have offset opening patterns (e.g., vias).

[0005] Another embodiment of the structure may include a chip and a board. The chip may be housed in a package and mounted on the board. The structure may also include a first magnetic shield adjacent to the package and opposite to the board, and a second magnetic shield adjacent to the board and opposite to the chip. Both the first and second magnetic shields may include at least a first magnetic layer and a second magnetic layer adjacent to the first magnetic layer. Furthermore, within each magnetic shield, the first and second magnetic layers may have different magnetic properties and / or misaligned opening patterns.

[0006] It should be noted that all aspects, examples, and features of the disclosed embodiments mentioned in the foregoing summary can be combined in any technically possible manner. That is, two or more aspects of any disclosed embodiment, including those described in the summary section, can be combined to form embodiments not specifically described herein. Details of one or more embodiments are set forth in the drawings and the following description. Other features, objects, and advantages will be apparent from the specification, drawings, and claims. Attached Figure Description

[0007] This disclosure will be better understood through the following detailed description with reference to the accompanying drawings, which are not necessarily drawn to scale, wherein:

[0008] Figure 1.1 , 1.2 Figures 1 and 1.3 are cross-sectional views showing embodiments of structures 100.1, 100.2, and 100.3, respectively;

[0009] Figure 2.1 , 2.2 Figures 2 and 2.3 are cross-sectional views showing additional embodiments of structures 200.1, 200.2, and 200.3, respectively;

[0010] Figure 3 This is a graph comparing the shielding efficiency of a single magnetic layer with that of a multi-layer magnetic shield; and

[0011] Figures 4A-4C These are perspective views showing different examples of misaligned through-hole patterns in different magnetic layers of a magnetic screen. Detailed Implementation

[0012] As mentioned above, MRAM has become a preferred embedded NVM option due to its high speed and stability within the automotive temperature range. Unfortunately, the magnetic diastolic properties of such MRAMs may be insufficient in environments with strong magnetic fields. For the purposes of this disclosure, the magnetic diastolic properties of MRAM refer to its ability to resist disturbance by external magnetic fields. One technique for improving the magnetic diastolic properties of MRAM is the use of a magnetic shield. However, currently available magnetic shields typically target narrow magnetic field ranges and may be prohibitively expensive.

[0013] In view of the above, this document discloses an embodiment of a structure comprising: a chip having eMRAM or other on-chip components susceptible to performance degradation induced by magnetic fields; and a magnetic shield for protecting the chip. In some embodiments of this structure, the magnetic shield may be adjacent to the chip and may include at least two adjacent magnetic layers with different magnetic properties. By including magnetic layers with different magnetic properties, a trade-off can be made between overall shielding efficiency and the range of magnetic field strength covered by the magnetic shield. In other embodiments of this structure, the magnetic shield may be adjacent to the chip and may include at least two adjacent magnetic layers with a staggered via pattern. By including a staggered via pattern in the magnetic layers, the total amount of magnetic material used for the magnetic shield can be reduced, thus reducing costs. In these embodiments, the magnetic layers may be made of the same magnetic material or different magnetic materials (e.g., again used to provide a trade-off between shielding efficiency and the range of magnetic field strength covered by the magnetic shield). In any case, the chip may be mounted on a board and housed in a package. Such magnetic shields can be located on the package (opposite to the board) and / or on the board (opposite to the chip), depending on the intended location of the potentially harmful magnetic field.

[0014] Figure 1.1 , 1.2 Figures 1 and 1.3 are cross-sectional views showing embodiments of structures 100.1, 100.2, and 100.3, respectively. Figure 2.1 , 2.2 Figures 2 and 2.3 are cross-sectional views showing additional embodiments of structures 200.1, 200.2, and 200.3, respectively.

[0015] In each of these embodiments, structures 100.1-100.3, 200.1-200.3 may include an integrated circuit chip 15 (hereinafter referred to as chip 115). Chip 115 may include at least one on-chip component 119, 219, which is susceptible to performance degradation induced by magnetic fields. For example, in some embodiments, the on-chip component 119, 219 may be an embedded magnetic random access memory (eMRAM) architecture. In addition, chip 115 may include a variety of other conventional on-chip components. Other on-chip components may include, but are not limited to, one or more input / output components, one or more computer processing units, one or more sensors, etc.

[0016] Chips 115 and 215 can be housed within chip packages 110 and 210 (also referred to herein as modules). That is, chips 115 and 215 can be mounted on substrates 111 and 211 (e.g., laminated substrates) and covered by lids 118 and 218. As shown, chips 115 and 215 can be flip-chip mounted within chip packages 110 and 210. Specifically, chips 115 and 215 can be flipped relative to substrates 111 and 211 such that the uppermost back-to-office (BEOL) surface is close to the top surface of substrates 111 and 211, and chips 115 and 215 can be electrically connected to substrates 111 and 211 via controlled collapse chip connections (C4 connections) 117 and 217. Lids 118 and 218 can be, for example, ceramic lids, plastic lids, or any other suitable IC packaging material lids. Covers 118 and 218 may also have sidewalls that laterally surround chip 115 and are attached to the top surfaces of substrates 111 and 211 by adhesives 112 and 212. Optionally, thermal interface materials 116 and 216 may be sandwiched between the bottom surfaces of chips 115 and 215 and covers 118 and 218. Alternatively, chips 115 and 215 may be packaged within chip packages 110 and 210 using any known or later-developed chip packaging technology. For example, the chip may be positioned such that the uppermost BEOL surface is away from the top surface of the substrate. In this case, the chip may be electrically connected to the substrate via wires (not shown). Furthermore, the covers may at least cover the outermost surface of the chip opposite the substrate.

[0017] In any case, chip packages 110, 210 and other chip packages and / or components (not shown) may be mounted (e.g., via solder bumps 102, 202) on boards 101, 201 (e.g., printed circuit boards (PCBs) or system boards). Boards 101, 201 may be rigid laminated non-conductive structures in which conductive lines are printed or etched to form traces. These traces, in conjunction with the solder bumps, provide electrical connections between boards 101, 201 and various onboard components, as well as electrical connections between different onboard components throughout boards 101, 201.

[0018] In each of these embodiments, structures 100.1-100.3, 200.1-200.3 may include at least one magnetic screen 150, 250 adjacent to chips 115, 215.

[0019] In some embodiments (for example, see Figure 1.1 Structure 100.1 and Figure 2.1Structure 200.1), magnetic shields 150, 250 are adjacent to the outermost surfaces of the cover 118, 218 of chip packages 110, 210 opposite to the boards 101, 201. That is, in some embodiments, chip packages 110, 210 are stacked between boards 101, 201 and magnetic shields 150, 250. In this case, magnetic shields 150, 250 can be positioned to provide protection (e.g., shielding) against the effects of the intended magnetic fields 199, 299 on the side of structures 100.1, 200.1 closest to chips 115, 215 (i.e., close to cover 118, 218).

[0020] In other embodiments (for example, see...) Figure 1.2 Structure 100.2 and Figure 2.2 Structure 200.2), magnetic shields 150, 250 are adjacent to the outermost surfaces of boards 101, 201 opposite to chip packages 110, 210. That is, in these embodiments, boards 101, 201 are stacked between magnetic shields 150, 250 and chip packages 110, 210. In this case, magnetic shields 150, 250 can be positioned to provide protection (e.g., shielding) against the effects of desired magnetic fields 199, 299 on the side of structures 100.2, 200.2 that are close to boards 101, 201.

[0021] In other embodiments (e.g., see...), Figure 1.3 The structure 100.3 and Figure 2.3 In structure 200.3), the first magnetic shields 150a and 250a are adjacent to the outermost surfaces of the cover plates 118 and 218 of the chip packages 110 and 210, which are opposite to the plates 101 and 201, and the second magnetic shields 150b and 250b are adjacent to the outermost surfaces of the plates 101 and 201, which are opposite to the chip packages 110 and 210. That is, in these embodiments, the plates 101 and 201 are stacked between the magnetic shields 150 and 250 and the chip packages 110 and 210. In this configuration, the first magnetic shields 150a and 250a can be positioned to provide protection (e.g., shielding) against the influence of the first intended magnetic field 199a and 299a on the side of structures 100.3 and 200.3 closest to chips 115 and 215 (i.e., close to covers 118 and 218), while the second magnetic shields 150b and 250b can be positioned to provide protection (e.g., shielding) against the influence of the second intended magnetic field 199b and 299b on the side of structures 100.3 and 200.3 close to plates 101 and 201.

[0022] It should be noted that the intended magnetic field can be an internal magnetic field generated within the product including structures 100.1.1-100.3 and 200.1-200.3. For example, the product (e.g., computerized equipment, smartphone, headset, earphone, etc.) may include a housing and chip packages 110, 210 within the housing and magnetic speakers or other magnetizing devices adjacent to one or the other side of the chip packages 110, 210, thus requiring a magnetic shield.

[0023] For specific references Figure 1.1-1.3 Structures 100.1-100.3, in some embodiments, the magnetic shield 150 (or, the first and second magnetic shields 150a-150b (if applicable)) may include a plurality of adjacent magnetic layers (i.e., multiple magnetic layer stacks, where one magnetic layer is adjacent to another) adjacent to the chip 115. For example, such a magnetic shield 150 may include a first magnetic layer 151 adjacent to the chip 115, a second magnetic layer 152 adjacent to the first magnetic layer 151, and optionally, one or more additional magnetic layers stacked on the second magnetic layer (e.g., see a third magnetic layer 153 adjacent to the second magnetic layer 152). In any case, different magnetic layers (e.g., the first magnetic layer 151, the second magnetic layer 152, and optionally the third magnetic layer 153) or more magnetic layers may have different magnetic properties. The different magnetic properties discussed may be permeability (μ r Magnetic permeability (Hsat) and magnetic saturation. Those skilled in the art will recognize that permeability refers to the measure of magnetization produced in a material in response to an applied magnetic field. That is, magnetic materials with internal dipoles that readily orient themselves with an applied magnetic field have high permeability, and vice versa. Magnetic saturation refers to a level of magnetization above which the material can no longer be magnetized. That is, magnetic materials with greater magnetization capacity have higher magnetic saturation, and vice versa.

[0024] For example, the first magnetic layer 151 may have a first permeability and a first magnetic saturation. The second magnetic layer may have a second permeability different from the first permeability and a second magnetic saturation different from the first magnetic saturation. The third magnetic layer 153 (if applicable) may have a third permeability different from the first and second permeabilities, and may also have a third magnetic saturation different from the first and second magnetic saturations.

[0025] For example, the first magnetic layer 151 may be close to the chip 115 (i.e., closest to the chip 115), on which other magnetic layers are stacked (e.g., such that the third magnetic layer 153 is adjacent to the second magnetic layer 152 and opposite to the first magnetic layer 151, and therefore away from the chip 115). In this case, the magnetic materials of the first magnetic layer 151, the second magnetic layer 152, and the third magnetic layer 153 (if applicable) may such that: (a) the first permeability, the second permeability, and the third (or even more) permeability may increase (i.e., the first permeability < the second permeability < the third permeability); and (b) the first magnetic saturation, the second magnetic saturation, and the third magnetic saturation decrease (i.e., the first magnetic saturation > the second magnetic saturation > the third magnetic saturation). Alternatively, the magnetic materials of the first magnetic layer 151, the second magnetic layer 152, and the third magnetic layer 153 (if applicable) may such that: (a) the first, second, and third permeability may decrease in order (i.e., first permeability > second permeability > third permeability); and (b) the first, second, and third magnetic saturation may increase in order (i.e., first magnetic saturation < second magnetic saturation < third magnetic saturation). It should be noted that the above examples are given for illustrative purposes and are not intended to be limiting. For example, alternatively, the second permeability may be higher than or lower than both the first and third permeability.

[0026] Examples of magnetic materials that may be used in the magnetic shield 150 include, but are not limited to, mu-metal, steel, and iron-cobalt alloys. Mu-metal is a nickel-based alloy (e.g., nickel-iron alloy, nickel-iron-copper alloy, nickel-iron-copper-chromium alloy, or nickel-iron-copper-molybdenum alloy), which can have relatively high permeability and correspondingly relatively low magnetic saturation. Iron-cobalt alloys can have relatively low permeability and relatively high magnetic saturation. Steel (e.g., iron-carbon alloy) can have moderate permeability and moderate magnetic saturation between that of mu-metal and iron-cobalt. Therefore, the first magnetic layer 151 may be mu-metal, the second magnetic layer 152 may be steel, and the third magnetic layer 153 (if applicable) may be iron-cobalt. Alternatively, the first magnetic layer 151 may be iron-cobalt, the second magnetic layer 152 may be steel, and the third magnetic layer 153 (if applicable) may be mu-metal. In some embodiments, the ratio of the maximum to the minimum permeability of the different layers varies by more than an order of magnitude.

[0027] It should be noted that, as described above and Figure 1.1-1.3 In each embodiment shown, each magnetic shield 152 is depicted as comprising a total of three magnetic layers. However, it should be understood that these figures are not intended to be limiting. Alternatively, each magnetic shield 150 may comprise two or more magnetic layers. Furthermore, in Figure 1.3 In the embodiment shown with a pair of magnetic screens 150a and 150b, the two magnetic screens may be substantially the same, or the two magnetic screens may be different (e.g., different numbers of magnetic layers, different magnetic properties, and / or different thicknesses).

[0028] By including magnetic layers 151-152 with different magnetic properties in the magnetic shield 150 of structures 100.1-100.3, a trade-off can be made between the overall shielding efficiency and the range of the magnetic field covered by the magnetic shield. Those skilled in the art will recognize that the magnetic field can be defined in Oersted (Oe), which is the consistent derived unit of the auxiliary magnetic field H in the centimeter-gram-second (CGS) unit system. Figure 3 As shown in the diagram, magnetic screens made of a single layer of magnetic material typically have low shielding efficiency but cover a relatively wide range of magnetic field strengths (as shown by curve 301), or high shielding efficiency but only cover a relatively narrow range of field strengths (as shown by curve 302). However, when two such magnetic layers are joined together (e.g., as first and second magnetic layers 151-152 with different magnetic properties) to form a multilayer magnetic screen, the multilayer magnetic screen will have an overall shielding efficiency between that of the individual shielding efficiencies exhibited by the two magnetic materials, and will cover a range of magnetic field strengths that are also between those covered by the two magnetic materials (as shown by curve 303).

[0029] For specific references Figure 2.1-2.3 Structures 200.1-200.3, in some embodiments, the magnetic shield 250 (or, the first and second magnetic shields 250a-250b (if applicable)) may include a plurality of adjacent magnetic layers (i.e., a multi-layer stack, where one magnetic layer is adjacent to another) adjacent to the chip 215. For example, such a magnetic shield 250 may include a first magnetic layer 251 adjacent to the chip 215, a second magnetic layer 252 adjacent to the first magnetic layer 251, and optionally, one or more additional magnetic layers stacked on the second magnetic layer 252 (e.g., see a third magnetic layer 253 adjacent to the second magnetic layer 252). The first magnetic layer 251, the second magnetic layer 252, and the optional additional magnetic layer (e.g., the third magnetic layer 253) may be different magnetic materials with different magnetic properties (e.g., as described above for...). Figure 1.1-1.3 The structure described in detail in sections 100.1-100.3 is essentially the same as those sections, to achieve a trade-off between overall shielding efficiency and the range of magnetic field strengths covered. Alternatively, the magnetic layer can be made of the same magnetic material.

[0030] In any case, the magnetic layers of the magnetic shield 250 (e.g., the first magnetic layer 251, the second magnetic layer 252, and optionally the third magnetic layer 253) may have a pattern of misaligned openings 261, 262, 263 (e.g., through-holes or other mesh structures). For the purposes of this disclosure, a through-hole in the magnetic layer refers to a hole that extends vertically and completely through the magnetic layer from a first surface (e.g., the bottom surface) to a second surface (e.g., the top surface) opposite the first surface. For illustrative purposes, the pattern of misaligned openings 261, 262, 263 in each magnetic layer is described below and shown in the figures as a misaligned through-hole pattern. However, it should be understood that, alternatively, the misaligned opening pattern may be a misaligned opening pattern of a mesh structure.

[0031] For example, the first magnetic layer 251 may have a first pattern with a first through-hole 261 extending vertically through it. The second magnetic layer 252 may have a second pattern with a second through-hole 262 extending vertically through it. The third magnetic layer 253 (if applicable) may have a third pattern with a third through-hole 263 extending vertically through it. As described above, the through-hole patterns in the different magnetic layers are misaligned. That is, none of the first through-holes 261 are aligned with either the second or third through-hole 262, none of the second through-holes 262 are aligned with either the first or third through-hole 263, and so on. Furthermore, ideally, none of the first through-holes 261 are even partially located below or above the second or third through-hole 262, and none of the second through-holes 262 are even partially located below or above the first or third through-hole 261, and so on. In other words, ideally, each first through hole 261 is completely misaligned with all second through holes 262 and third through holes 263, each second through hole 262 is completely misaligned with all first through holes 261 and third through holes 263, and so on.

[0032] It should be noted that the shape, size, number, and density of vias in each magnetic layer (e.g., the shape, size, number, and density of the first via 261, the second via 262, and the third via 263 (if applicable)) can be substantially the same. In this case, substantially identical patterns can be aligned during processing to ensure that each pattern is misaligned with the next. Alternatively, the shape, size, number, and / or density of vias in each magnetic layer can be different. For example, the shape, size, number, and / or density of vias in the first via 261, the second via 262, and the third via 263 (if applicable) or any additional magnetic layer within the magnetic shield can be different. In this case, different patterns can be designed and aligned during processing to ensure that each pattern is misaligned with the next.

[0033] Figures 4A-4CThese are perspective views illustrating different examples of misaligned through-hole patterns in different magnetic layers of the magnetic shield 250. As shown, each view includes: a first pattern (e.g., a first through-hole, as shown in black) of a first opening 261 in a first magnetic layer 251; a second pattern (e.g., a second through-hole, as shown in white) of a second opening 262 in a second magnetic layer 252; and a third pattern (e.g., a third through-hole, as shown in gray) of a third opening 263 in a third magnetic layer 253. Figure 4A In the example, the first, second, and third vias 261-263 in the first, second, and third magnetic layers 251-253 have similar shapes, sizes, and densities. Figure 4B In the example, the first, second, and third through-holes 261-263 in the first, second, and third magnetic layers 251-253 also have different dimensions. Figure 4C In the example, the first, second and third through holes 261-263 in the first, second and third magnetic layers 251-253 also have different shapes, sizes and densities.

[0034] By including a magnetic layer 251-253 with a pattern of misaligned through holes 261-263 in the magnetic shield 250 of structures 200.1-200.3, the total amount of magnetic material required for the magnetic shield can be reduced, thereby reducing the cost of manufacturing the magnetic shield.

[0035] In the structure disclosed herein (e.g., Figure 1.1-1.3 Structures 100.1-100.3 and Figure 2.1-2.3 In various embodiments of structures 200.1-200.3, the total thickness of the magnetic shields 150, 250 can be predetermined to achieve a predetermined trade-off between shielding efficiency and size and / or cost. For example, the magnetic shields 150, 250 can be about 0.5 millimeters (mm), thus providing an acceptable amount of shielding efficiency without being too costly.

[0036] It should be noted that, as described above and in Figure 2.1-2.3 In each embodiment shown, each magnetic shield 250 is depicted as comprising a total of three magnetic layers. However, it should be understood that these figures are not intended to be limiting. Alternatively, each magnetic shield 250 may comprise two or more magnetic layers. Furthermore, in Figure 2.3 In the embodiment shown with a pair of magnetic screens 250a and 250b, the two magnetic screens may be substantially identical, or they may be different (e.g., different numbers of magnetic layers, different magnetic properties, different via patterns, and / or different thicknesses). Furthermore, although not shown, various additional embodiments are contemplated. For example, in a structure with a pair of magnetic screens, one of the magnetic screens may be configured to be substantially identical to magnetic screen 150 described above, and the other magnetic screen may be configured to be substantially identical to magnetic screen 250 described above.

[0037] This document also discloses the methods used to form the above detailed description and in Figure 1.1-1.3 The method embodiments of the structures shown in 2.1-2.3 (e.g., structures 100.1-100.3, 200.1-200.3) are described. This method may include forming chips 115, 215 (including at least one on-chip component 119, 219, such as eMRAM, susceptible to performance degradation induced by magnetic fields), and further manufacturing chip packages 110, 210 that house the chips 115, 215. Techniques for forming chips and for manufacturing chip packages that house chips are well known in the art. Therefore, details thereof have been omitted from this specification to allow the reader to focus on the prominent aspects of the disclosed embodiments.

[0038] Some embodiments of the method may include those forming the detailed description above and in Figure 1.1-1.3 One or more magnetic shields 150 are shown. To form such a magnetic shield 150, plates of different magnetic materials can be selected for different magnetic layers. The plate for the first magnetic layer 151 can then be attached to the outermost surface of the cover 118 or plate 101 using an adhesive (e.g., an epoxy-based adhesive). The plate for the second magnetic layer 152 can be bonded to the outermost surface of the plate for the first magnetic layer 151 by, for example, cold roll bonding (CRB). Those skilled in the art will recognize that CRB refers to a solid-state welding process that joins two or more sheets of metal together by rolling (e.g., at room temperature). Alternatively, any other suitable known or later-developed technique for bonding magnetic layers without an insulator between them can be used. For example, the magnetic layers of a multilayer magnetic shield can be formed by a deposition process (e.g., a physical vapor deposition (PVD) process). Similarly, the plate for the third magnetic layer 153 can be bonded to the outermost surface of the plate for the second magnetic layer 152 by CRB or any other suitable known or later-developed technique for bonding magnetic layers without an insulator between them.

[0039] Other embodiments of the method may include those described in the detailed description above and in Figure 2.1-2.3One or more magnetic shields 250 are shown. To form such magnetic shields 250, plates of the same or different magnetic materials can be selected for different magnetic layers. Each plate can then be patterned with a corresponding through-hole pattern such that the through-hole patterns of the layers will be staggered. For example, the through-hole patterning can be achieved using a masking etching process, a punching process, or any other suitable technique for patterning openings through the plates. After the through-hole patterning, the plate with the first through-hole 261 for the first magnetic layer 251 can then be attached to the outermost surface of the cover 218 or plate 201 using an adhesive (e.g., an epoxy-based adhesive). The plate with the second through-hole 262 for the second magnetic layer 252 can be attached to the outermost surface of the plate for the first magnetic layer 251 using, for example, CRB or any other suitable known or later developed technique for bonding magnetic layers without an insulator between them. Similarly, the plate with the third through-hole 263 for the third magnetic layer 253 can be joined to the outermost surface of the plate for the second magnetic layer 252 using CRB or any other suitable known or later developed technique for joining magnetic layers without an insulator between them. Alternatively, as described above, the magnetic layers with misaligned opening patterns can be different mesh structures joined together using any suitable joining technique.

[0040] It should be understood that, in the method embodiments disclosed herein, the design decision to place magnetic screens 150, 250 on one or both sides of chips 115, 215 depends on the inclusion of Figure 1.1-1.3 Structure 100.1-100.3 or Figure 2.1-2.3 The structure 200.1-200.3 specifies the intended location of potential harmful magnetic fields inside or near the product. Furthermore, the total thickness of the magnetic shield, the number of magnetic layers in the magnetic shield, the different magnetic properties of the magnetic layers in the magnetic shield, and / or the size, shape, density, and number of vias in the misaligned via pattern within the magnetic layers can all be predetermined to achieve a predetermined trade-off between shielding efficiency and size and / or cost.

[0041] It should be understood that the terminology used herein is for describing the disclosed structures and methods and is not intended to be limiting. For example, as used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms, unless the context clearly indicates otherwise. Furthermore, as used herein, the terms “comprises,” “comprising,” “includes,” and / or “including” specify the presence of the stated features, integrals, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof. Moreover, as used herein, when oriented and shown in figures, terms such as “right,” “left,” “vertical,” “horizontal,” “top,” “bottom,” “upper,” “lower,” “below,” “under,” “under,” “above,” “overlapping,” “parallel,” “vertical,” etc., are intended to describe relative positions (unless otherwise stated), and terms such as “touches,” “directly contacts,” “adjacent,” “directly adjacent,” “closely adjacent,” etc., are intended to indicate that at least one element is in physical contact with another element (without any other element separating the elements). The term "lateral" is used herein to describe the relative position of elements, and more specifically, when elements are oriented and shown in a figure, to indicate that one element is located to the side of another element, rather than above or below it. For example, an element laterally adjacent to another element will be beside the other element, an element laterally directly adjacent to another element will be directly beside the other element, and an element laterally surrounding another element will be adjacent to and bound to the outer wall of the other element. All corresponding structures, materials, actions, and equivalents of the means or steps plus functional elements in the following claims are intended to include any structures, materials, or actions used to perform a function in combination with other elements of the specific claims.

[0042] The methods described above are used for the manufacture of integrated circuit chips. The resulting integrated circuit chips can be distributed by the manufacturer in the form of raw wafers (i.e., as a single wafer with multiple unpackaged chips), as dies, or in packages. In the latter case, the chips are mounted in single-chip packages (e.g., plastic carriers with leads attached to a motherboard or other higher-level carriers) or multi-chip packages (e.g., ceramic carriers with either surface-mount or buried interconnects, or both). In any case, the chips are then integrated with other chips, discrete circuit elements, and / or other signal processing devices as part of (a) an intermediate product (e.g., a motherboard) or (b) a final product. The final product can be any product that includes the integrated circuit chips, ranging from toys and other low-end applications to advanced computer products with displays, keyboards or other input devices, and central processing units.

[0043] The descriptions of various disclosed embodiments are given for illustrative purposes and are not intended to be exhaustive or limiting. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the disclosed embodiments. The terminology used herein is chosen to best explain the principles of the embodiments, practical applications of techniques found in the market, or improvements to techniques, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A structure comprising: chip; as well as A magnetic screen, adjacent to the chip, wherein the magnetic screen comprises: First magnetic layer; and The second magnetic layer is adjacent to the first magnetic layer and has different magnetic properties from the first magnetic layer.

2. The structure according to claim 1, in, The first magnetic layer has a first magnetic permeability and a first magnetic saturation; and The second magnetic layer has a second magnetic permeability that is different from the first magnetic permeability and a second magnetic saturation that is different from the first magnetic saturation.

3. The structure according to claim 2, in, The magnetic shield further includes: at least one additional magnetic layer, comprising a third magnetic layer adjacent to the second magnetic layer and opposite to the first magnetic layer, and The third magnetic layer has a third magnetic permeability that is different from the first and second magnetic permeabilities, and also has a third magnetic saturation that is different from the first and second magnetic saturations.

4. The structure according to claim 3, in, The first magnetic layer is close to the chip, and the third magnetic layer is far from the chip. The first magnetic permeability, the second magnetic permeability, and the third magnetic permeability increase or decrease in that order.

5. The structure according to claim 3, in, The first magnetic layer is close to the chip, and the third magnetic layer is far from the chip. Wherein, the second magnetic permeability is higher than the first magnetic permeability and the third magnetic permeability, or lower than the first magnetic permeability and the third magnetic permeability.

6. The structure according to claim 1, further comprising: A board in which the chip is housed within a package and mounted on the board.

7. The structure according to claim 6, wherein, The magnetic shield is adjacent to the package and opposite to the board.

8. The structure according to claim 7, further comprising: An additional magnetic shield is attached to the board and opposite the chip.

9. The structure according to claim 6, wherein, The magnetic screen is adjacent to the board and opposite to the chip.

10. The structure according to claim 1, wherein, The chip includes an embedded magnetic random access memory, wherein the magnetic screen enhances the magnetic immunity of the embedded magnetic random access memory to adjacent magnetic fields.

11. A structure comprising: chip; as well as A magnetic screen, adjacent to the chip, wherein the magnetic screen comprises: First magnetic layer; and A second magnetic layer is adjacent to the first magnetic layer, wherein the first magnetic layer and the second magnetic layer have misaligned opening patterns.

12. The structure according to claim 11, wherein, The first magnetic layer and the second magnetic layer have the same magnetic properties or different magnetic properties.

13. The structure according to claim 11, wherein, The first magnetic layer has a first through hole, and the second magnetic layer has a second through hole that is completely misaligned with the first through hole.

14. The structure according to claim 13, wherein, The magnetic screen further includes a third magnetic layer, which is adjacent to the second magnetic layer and opposite to the first magnetic layer, and also has a third through hole that is completely misaligned with the first through hole and the second through hole.

15. The structure according to claim 13, wherein, The shape, size, and number of the first through hole and the second through hole are different.

16. The structure according to claim 11, further comprising: A board in which the chip is housed within a package and mounted on the board.

17. The structure according to claim 16, wherein, The magnetic shield is adjacent to the package and opposite to the board.

18. The structure according to claim 17, further comprising: An additional magnetic shield is attached to the board and opposite the chip.

19. The structure according to claim 16, wherein, The magnetic screen is adjacent to the board and opposite to the chip.

20. A structure comprising: chip; as well as A board, wherein the chip is housed within a package and mounted on the board; A first magnetic shield, which is adjacent to the package and opposite to the plate; and The second magnetic screen is adjacent to the board and opposite to the chip. Wherein, both the first magnetic screen and the second magnetic screen include at least: a first magnetic layer; and a second magnetic layer adjacent to the first magnetic layer, and The first magnetic layer and the second magnetic layer have different magnetic properties and any of the misaligned opening patterns.

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