Electronic circuit packaging and electronic equipment

Abstract

The present application provides an electronic circuit package and an electronic device, and relates to the field of electronic packaging technology. The electronic circuit package includes: a substrate, an electronic device, a plastic sealing layer and a composite magnetic conductive layer; a grounding layer is formed on the substrate; the electronic device is arranged on the surface of the substrate; the plastic sealing layer covers the surface of the substrate and wraps the electronic device; the composite magnetic conductive layer at least covers the upper surface of the plastic sealing layer; wherein the composite magnetic conductive layer includes a stacked first magnetic conductive layer and a second magnetic conductive layer, the first magnetic conductive layer includes a plurality of stacked cobalt-zirconium-tantalum alloy layers, the second magnetic conductive layer includes a plurality of stacked nickel-iron alloy layers, and an isolation layer is provided between each two adjacent cobalt-zirconium-tantalum alloy layers and between each two adjacent nickel-iron alloy layers.

Description

Technical Field

[0001] The present application relates to the technical field of electronic packaging, and in particular to an electronic circuit package and an electronic device. Background Art

[0002] The demand for thinner and higher performance of electronic devices such as mobile phones, watches, and True Wireless Stereo (TWS) headphones is driving system-level integration and modularization, resulting in the application of more and more System in Package (SiP) chips.

[0003] Taking mobile phones as an example, with the development of the fifth generation mobile communication technology (5G), the introduction of more antennas and the expansion of battery capacity have brought greater space pressure to the motherboard in the mobile phone, causing the size of the mobile phone motherboard to be further reduced. The chips on the motherboard are further modularized to make SiP chips, such as RF SiP, WiFi SiP and power management chip (Power Management Integrated Circuit, PMIC) SiP.

[0004] Figure 1 It is a diagram of the internal structure of a mobile phone. With the development of miniaturization and high density of mobile phones, the mainboard 101, antenna module 102 and camera module 103 in the mobile phone 01 are very close. In addition, the SiP chip 100 on the mainboard 101 is arranged more and more closely, which may cause electromagnetic interference problems, such as electromagnetic interference between SiP chips 100 and electromagnetic interference between SiP chip 100 and other modules (such as camera module 103, antenna module 102, etc.).

[0005] Figure 2 It is a packaging structure diagram of a SiP chip. In order to reduce these electromagnetic interferences, the plastic packaging material 3 wraps various electronic devices 1 in the form of packaging, and then copper, stainless steel and other metals are sputtered onto the surface of the plastic packaging material 3 by physical vapor deposition (PVD) to form a metal layer 4. The metal layer 4 is then grounded to the ground layer 201 of the substrate 2 to achieve electromagnetic isolation of multiple electronic devices 1.

[0006] Figure 3 yes Figure 2 The shielding effect of the metal layer 4 in the embodiment is copper with a thickness of 3 μm. Figure 3It can be seen from the data shown that the metal layer 4 can achieve an electromagnetic shielding effect of more than 40dB at a frequency above 500MHz, which can basically meet the electromagnetic shielding needs of the RF SiP; it can achieve an electromagnetic shielding effect of more than 30dB at 100MHz, and an electromagnetic shielding effect of more than 10dB at 10MHz. As for the low-frequency shielding effect below 500MHz, it cannot meet the low-frequency shielding requirements of future PMIC SiP, baseband and other SiPs.

[0007] Therefore, it is necessary to design a new shielding structure to improve the shielding effect of the low-frequency (not more than 500MHz) frequency band, to meet the SIP chip application scenarios with high requirements for low-frequency band shielding, and to further reduce the electromagnetic interference problems between chips and chips, and between chips and modules. Summary of the invention

[0008] The present application provides an electronic circuit package and an electronic device, the main purpose of which is to improve the low-frequency shielding effect.

[0009] In order to achieve the above objectives, this application adopts the following technical solutions:

[0010] In the first aspect, the present application provides an electronic circuit package, comprising: a substrate, an electronic device, a plastic sealing layer and a composite magnetic conductive layer; a grounding layer is formed on the substrate; the electronic device is arranged on the surface of the substrate; the plastic sealing layer covers the surface of the substrate and wraps the electronic device; the composite magnetic conductive layer at least covers the upper surface of the plastic sealing layer; wherein the composite magnetic conductive layer comprises a stacked first magnetic conductive layer and a second magnetic conductive layer, the first magnetic conductive layer comprises a stacked plurality of cobalt-zirconium-tantalum alloy layers, the second magnetic conductive layer comprises a stacked plurality of nickel-iron alloy layers, and an isolation layer is provided between each two adjacent cobalt-zirconium-tantalum alloy layers and between each two adjacent nickel-iron alloy layers.

[0011] The electronic circuit package provided by the present application is a composite magnetic conductive layer, and the composite magnetic conductive layer is a laminated structure, wherein the first magnetic conductive layer in the laminated structure is stacked by a plurality of cobalt-zirconium-tantalum alloy layers, and the multilayer cobalt-zirconium-tantalum alloy layers with higher magnetic permeability are separated by an isolation layer, so that when the electromagnetic wave passes through the first magnetic conductive layer, multiple reflections will be formed to increase the propagation path of the electromagnetic wave; in addition, the second magnetic conductive layer in the laminated structure is stacked by a plurality of nickel-iron alloy layers, and the multilayer nickel-iron alloy layers with higher magnetic permeability are separated by an isolation layer, so that when the electromagnetic wave passes through the second magnetic conductive layer, multiple reflections will also be formed to increase the propagation path of the electromagnetic wave. The magnetic permeability and electrical conductivity of the cobalt-zirconium-tantalum material and the nickel-iron material are both in different ranges, so that a wider frequency range of interference shielding effect can be obtained, and multiple reflections can further realize the absorption of electromagnetic waves in a wider frequency band, thereby improving the low-frequency shielding effect compared with the prior art. Therefore, the composite magnetic conductive layer of the present application can improve the shielding effect on electromagnetic waves in the low-frequency band on the basis of achieving a good shielding effect on electromagnetic waves in the high-frequency band.

[0012] In a possible implementation of the first aspect, the first magnetic conductive layer is attached to the surface of the plastic sealing layer, and the second magnetic conductive layer is located on the side of the second magnetic conductive layer away from the plastic sealing layer. Since the cobalt-zirconium-tantalum material in the first magnetic conductive layer is generally an amorphous thin film material with low stress, it will not fall off when it is bonded to the plastic sealing layer.

[0013] In a possible implementation of the first aspect, the surfaces of the plastic encapsulation layer other than those in contact with the substrate are covered with a composite magnetic conductive layer, and the composite magnetic conductive layer is electrically connected to the ground layer. In other words, the surfaces of the plastic encapsulation layer other than those in contact with the substrate are covered with the composite magnetic conductive layer, so that the shielding effect is better.

[0014] In a possible implementation of the first aspect, the electronic circuit package further includes a metal layer, which is disposed between the composite magnetic conductive layer and the plastic sealing layer, or the metal layer is disposed on a side of the composite magnetic conductive layer away from the plastic sealing layer. By adding the metal layer, the shielding frequency range is made wider, further improving the shielding effect.

[0015] In a possible implementation of the first aspect, soft magnetic material particles are added to the plastic encapsulation layer, the soft magnetic material is a soft magnetic alloy material, and the outside of the soft magnetic material particles is covered by an insulating layer. By adding soft magnetic alloy material to the plastic encapsulation layer, the shielding effect of electromagnetic waves in the low-frequency band can be further improved; in addition, by covering the outside of the soft magnetic material particles with an insulating layer, the phenomenon of some electronic devices that do not need to be electrically connected being electrically connected through soft magnetic material particles can be prevented.

[0016] In a possible implementation manner of the first aspect, the soft magnetic material is a nickel-iron alloy, an iron-silicon-chromium alloy, or a cobalt-iron alloy.

[0017] In a possible implementation manner of the first aspect, an average radial size of the soft magnetic material particles is 10 μm-50 μm.

[0018] In a possible implementation manner of the first aspect, the isolation layer is a conductive layer or an insulating layer.

[0019] In a possible implementation of the first aspect, the material of the conductive layer is Cu, Al, Ni, Ti, etc.

[0020] In a possible implementation of the first aspect, the material of the insulating layer is SiO2, Ta2O, Al2O3, etc.

[0021] In a possible implementation manner of the first aspect, the magnetic permeability of the first magnetic conductive layer is 100-2000, and the electrical conductivity of the first magnetic conductive layer is 50 uΩ·cm-200 uΩ·cm; and / or;

[0022] The magnetic permeability of the second magnetic conductive layer is 100-600, and the electrical conductivity of the first magnetic conductive layer is 1 uΩ·cm-50 uΩ·cm.

[0023] In a possible implementation manner of the first aspect, the magnetic permeability of the first magnetic conductive layer is 500-1200, and the electrical conductivity of the first magnetic conductive layer is 50 uΩ·cm-100 uΩ·cm; and / or;

[0024] The magnetic permeability of the second magnetic conductive layer is 300-500, and the electrical conductivity of the first magnetic conductive layer is 20 uΩ·cm-40 uΩ·cm.

[0025] On the second aspect, the present application also provides an electronic circuit package, including a substrate, an electronic device, a plastic sealing layer and a metal layer; a grounding layer is formed on the substrate; the electronic device is arranged on the surface of the substrate; the plastic sealing layer covers the surface of the substrate and wraps the electronic device, the plastic sealing layer is doped with soft magnetic material particles, the soft magnetic material is a soft magnetic alloy material, and the outside of the soft magnetic material particles is covered by an insulating layer; the metal layer covers the surface of the plastic sealing layer and is electrically connected to the grounding layer.

[0026] The electronic circuit package provided by the present application has soft magnetic alloy materials doped in the plastic sealing layer. These soft magnetic alloy materials have the characteristics of absorbing and reflecting electromagnetic waves. Therefore, these soft magnetic alloy materials can achieve the absorption of electromagnetic waves in a wider frequency range, thereby improving the low-frequency shielding effect compared with the prior art. Because the soft magnetic material is a soft magnetic alloy material, the outside of the soft magnetic material particles is covered by an insulating layer, and the insulating layer can effectively prevent the electronic devices that do not need to be electrically connected from being electrically connected through the soft magnetic alloy material.

[0027] In a possible implementation manner of the second aspect, the soft magnetic material is a nickel-iron alloy, an iron-silicon-chromium alloy, or a cobalt-iron alloy.

[0028] In a possible implementation manner of the second aspect, an average radial size of the soft magnetic material particles is 10 μm-50 μm.

[0029] In a possible implementation manner of the second aspect, an average radial size of the soft magnetic material particles is 20 μm-30 μm.

[0030] In a possible implementation of the second aspect, the electronic circuit package also includes a composite magnetic conductive layer, which is arranged between the plastic sealing layer and the metal layer, or the composite magnetic conductive layer is arranged on the side of the metal layer away from the plastic sealing layer; the composite magnetic conductive layer includes a stacked first magnetic conductive layer and a second magnetic conductive layer, the first magnetic conductive layer includes a stacked plurality of cobalt-zirconium-tantalum alloy layers, the second magnetic conductive layer includes a stacked plurality of nickel-iron alloy layers, and an isolation layer is provided between each two adjacent cobalt-zirconium-tantalum alloy layers and between each two adjacent nickel-iron alloy layers.

[0031] The first magnetic conductive layer in the stacked structure is stacked by multiple cobalt-zirconium-tantalum alloy layers, and the multiple cobalt-zirconium-tantalum alloy layers with higher magnetic permeability are separated by an isolation layer. In this way, the electromagnetic wave will form multiple reflections when passing through the first magnetic conductive layer; in addition, the second magnetic conductive layer in the stacked structure is stacked by multiple nickel-iron alloy layers, and the multiple nickel-iron alloy layers with higher magnetic permeability are separated by an isolation layer. Therefore, the electromagnetic wave will also form multiple reflections when passing through the second magnetic conductive layer. The above-mentioned multiple reflections can further realize the absorption of electromagnetic waves in a wider frequency band, thereby further improving the low-frequency shielding effect. In addition, the soft magnetic alloy material is added to the plastic sealing layer, which will further increase the shielding effect of low-frequency electromagnetic waves.

[0032] In a possible implementation of the second aspect, when the composite magnetic conductive layer is arranged between the plastic sealing layer and the metal layer, the first magnetic conductive layer is adhered to the surface of the plastic sealing layer, and the second magnetic conductive layer is located on the side of the first magnetic conductive layer away from the plastic sealing layer; when the composite magnetic conductive layer is arranged on the side of the metal layer away from the plastic sealing layer, the first magnetic conductive layer is adhered to the surface of the metal layer, and the second magnetic conductive layer is located on the side of the first magnetic conductive layer away from the metal layer.

[0033] In a possible implementation of the second aspect, when the composite magnetic conductive layer is arranged between the plastic sealing layer and the metal layer, the remaining surface of the plastic sealing layer except the surface in contact with the substrate is covered with the composite magnetic conductive layer, and the composite magnetic conductive layer is electrically connected to the ground layer; when the composite magnetic conductive layer is arranged on the side of the metal layer away from the plastic sealing layer, the remaining surface of the metal layer except the surface in contact with the substrate is covered with the composite magnetic conductive layer.

[0034] In a possible implementation manner of the second aspect, the isolation layer is a conductive layer or an insulating layer.

[0035] In a third aspect, the present application further provides an electronic device, comprising a printed circuit board and an electronic circuit package in any implementation of the first aspect, or an electronic circuit package in any implementation of the second aspect, wherein the printed circuit board is electrically connected to the electronic circuit package.

[0036] The electronic device provided in the embodiment of the present application includes the electronic circuit package of the first aspect embodiment or the second aspect embodiment. Therefore, the electronic device provided in the embodiment of the present application and the electronic circuit package of the above technical solution can solve the same technical problems and achieve the same expected effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the internal structure of a mobile phone;

[0038] Figure 2 It is a schematic diagram of the structure of the electronic circuit package of the prior art;

[0039] Figure 3 for Figure 2 Shielding effect diagram;

[0040] Figure 4 A schematic diagram of a portion of the structure of an electronic device according to an embodiment of the present application;

[0041] Figure 5 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0042] Figure 6 A partial structural diagram of an electronic circuit package provided by an embodiment of the present application taken with a scanning electron microscope;

[0043] Figure 7 A schematic diagram of the structure of the first magnetic conductive layer provided in an embodiment of the present application;

[0044] Figure 8 A path diagram of electromagnetic wave propagation in the first magnetic conductive layer provided in an embodiment of the present application;

[0045] Fig. 9 A schematic diagram of the structure of the second magnetic conductive layer provided in an embodiment of the present application;

[0046] Fig.10 A path diagram of electromagnetic wave propagation in the second magnetic conductive layer provided in an embodiment of the present application;

[0047] Fig.11 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0048] Fig.12 for Fig.11 A comparison chart of the shielding effect of and the shielding effect of the prior art;

[0049] Fig.13 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0050] Fig.14 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0051] Fig.15 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0052] Fig.16 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0053] Fig.17 is a structural diagram of soft magnetic material particles;

[0054] Fig.18 A partial structural diagram of an electronic circuit package provided by an embodiment of the present application taken with a scanning electron microscope;

[0055] Fig.19 for Fig.16 A comparison chart of the shielding effect of and the shielding effect of the prior art;

[0056] Fig. 20 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0057] Fig.21 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0058] Fig. 22 A schematic diagram of the structure of an electronic circuit package provided in an embodiment of the present application;

[0059] Fig.23 for Fig. 22 A comparison chart of the shielding effect of and the shielding effect of the prior art;

[0060] Fig.24 A flowchart of a method for preparing an electronic circuit package provided in an embodiment of the present application.

[0061] Reference numerals:

[0062] 01-mobile phone; 100-SiP chip; 101-printed circuit board; 102-antenna module; 103-camera module; 104-electrical connection structure; 105-electronic circuit packaging; 1-electronic device; 2-substrate; 201-ground layer; 3-plastic sealing layer; 31-silicon powder; 4-metal layer; 5-composite magnetic conductive layer; 51-first magnetic conductive layer; 511-CZT alloy layer; 512-first isolation layer; 52-second magnetic conductive layer; 521-NiFe alloy layer; 522-second isolation layer; 6-soft magnetic material particles; 601-first soft magnetic material particles; 602-second soft magnetic material particles; 7-insulating layer. DETAILED DESCRIPTION

[0063] The embodiment of the present application provides an electronic device. The electronic device may include a mobile phone, a tablet computer (pad), a smart wearable product (e.g., a smart watch, a smart bracelet), a virtual reality (VR) device, an augmented reality (AR) device, and the like. The embodiment of the present application does not impose any special restrictions on the specific form of the above electronic device.

[0064] like Figure 4 As shown, the electronic device may include an electronic circuit package 105 and a printed circuit board (PCB) 101. The electronic circuit package 105 is electrically connected to the PCB 101 via an electrical connection structure 104. Thus, the electronic circuit package 105 can achieve signal transmission with other chips or other modules on the PCB 101.

[0065] The electrical connection structure 104 may be a ball grid array (BGA). In an alternative embodiment, the electrical connection structure 104 is a plurality of copper pillar bumps arranged in an array.

[0066] The structure of the electronic circuit package 105 is described in detail below.

[0067] Figure 5 The figure shows a structural diagram of an electronic circuit package 105 , which includes a substrate 2 and at least one electronic device 1 . The electronic device 1 is integrated on the surface of the substrate 2 and is electrically connected to the substrate 2 .

[0068] The electronic device 1 mentioned above can be an active device (such as a field effect transistor, a thyristor, etc.), or a passive device (such as a capacitor, an inductor, a relay, etc.), or it can be a chip integrating active and passive devices, which can be a RF SiP, a WiFi SiP or a PMIC SiP, etc.

[0069] In order to improve the strength of the entire electronic circuit package 105 and protect and reinforce the electronic device 1 integrated on the substrate 2, as shown in FIG. Figure 5 As shown, a plastic encapsulation layer 3 is covered on the surface of the substrate 2, and the plastic encapsulation layer 3 wraps the electronic device 1. The plastic encapsulation layer 3 is generally made of epoxy molding compound (EMC). Of course, other plastic encapsulation materials can also be used.

[0070] When the electronic device 1 includes a radio frequency SiP, a WiFi SiP, a PMIC SiP or other electronic structures, these electronic devices will release electromagnetic waves when working. In order to avoid electromagnetic interference between these electronic devices, or electromagnetic interference between these electronic devices and modules located around the electronic circuit package 105, for example, Figure 1 The interference between the antenna module 102 or the camera module 103 is shown as Figure 5 As shown, a shielding structure is formed on the surface of the plastic packaging layer 3, and the shielding structure can absorb electromagnetic waves to prevent mutual interference between various electronic devices.

[0071] Combination Figure 5 The shielding structure includes a composite magnetic conductive layer 5. The composite magnetic conductive layer 5 may only cover the upper surface A1 of the plastic packaging layer 3. In an optional embodiment, as Fig.11 The composite magnetic conductive layer 5 not only covers the upper surface A1 of the plastic encapsulation layer 3, but also covers the side surface A2 of the plastic encapsulation layer 3, that is, the remaining surfaces of the plastic encapsulation layer 3 except the surface in contact with the substrate 2 are all covered by the composite magnetic conductive layer 5. From the perspective of shielding effect, multi-surface coverage will further increase the shielding effect compared with only one-side coverage; from the perspective of preparation process, the composite magnetic conductive layer 5 is generally formed by sputtering, electroplating or coating, and multi-surface coverage will also simplify the difficulty of the entire preparation process compared with only one-side coverage.

[0072] When the composite magnetic conductive layer 5 covers not only the upper surface A1 of the plastic packaging layer 3, but also the side surface A2 of the plastic packaging layer 3, Fig.11 The composite magnetic conductive layer 5 on the side surface A2 of the plastic cover 3 extends to the side surface of the substrate 2 and is electrically connected to the ground layer 201. In this way, all the electronic devices 1 integrated on the substrate 2 can be surrounded in the shielding cavity formed by the composite magnetic conductive layer 5 and the ground layer 201, thereby achieving shielding isolation of these electronic devices 1 and achieving a better shielding effect.

[0073] like Figure 5 The composite magnetic conductive layer 5 includes a first magnetic conductive layer 51 and a second magnetic conductive layer 52 stacked together. Figure 6This is a physical picture taken by a scanning electron microscope of the first magnetic conductive layer 51 and the second magnetic conductive layer 52 stacked on the plastic encapsulation layer 3. Since the surface of the plastic encapsulation layer 3 will not be completely smoothed during the preparation process, the first magnetic conductive layer 51 and the second magnetic conductive layer 52 will be wavy, but this phenomenon caused by the process will almost have no effect on the shielding effect.

[0074] In some optional embodiments, the magnetic permeability of the first magnetic permeable layer is 100-2000, and the electrical conductivity of the first magnetic permeable layer is 50uΩ·cm-200uΩ·cm. In another optional embodiment, the magnetic permeability of the second magnetic permeable layer is 100-600, and the electrical conductivity of the first magnetic permeable layer is 1uΩ·cm-50uΩ·cm.

[0075] In another optional embodiment, the magnetic permeability of the first magnetic conductive layer is 500-1200, and the electrical conductivity of the first magnetic conductive layer is 50uΩ·cm-100uΩ·cm. In another optional embodiment, the magnetic permeability of the second magnetic conductive layer is 300-500, and the electrical conductivity of the first magnetic conductive layer is 20uΩ·cm-40uΩ·cm.

[0076] like Figure 7 As shown, the first magnetic conductive layer 51 includes a plurality of stacked cobalt-zirconium-tantalum (CZT) alloy layers 511, and a first isolation layer 512 is provided between each two adjacent CZT alloy layers 511, that is, the plurality of CZT alloy layers 511 are separated by the first isolation layer 512. Fig. 9 As shown, the second magnetic conductive layer 52 includes a plurality of stacked nickel-iron (NiFe) alloy layers 521 , and a second isolation layer 522 is provided between each two adjacent NiFe alloy layers 521 , that is, the plurality of NiFe alloy layers 521 are separated by the second isolation layer 522 .

[0077] Table 1 below shows the physical parameters of CZT and NiFe.

[0078]

[0079] Table 1

[0080] From the parameters in Table 1 above, it can be seen that both NiFe and CZT have high magnetic permeability and electrical conductivity, and the ferromagnetic resonance (FMR) frequency is also relatively large. The use of these two different materials is to obtain interference shielding effects in a wider frequency range. In addition, the ferromagnetic resonance FMR of the two materials can achieve a wider range of electromagnetic wave absorption in different frequency bands. In this way, it not only has a good shielding effect on high-frequency (greater than 500MHz) electromagnetic waves, but also improves the shielding effect on low-frequency (not greater than 500MHz) electromagnetic waves compared to the existing technology.

[0081] In an optional embodiment, the total thickness of the first magnetic conductive layer 51 is approximately 1 μm to 20 μm, the thickness of each CZT alloy layer 511 is approximately 1 μm to 5 μm, and the thickness of each first isolation layer 512 is 1 nm to 10 nm. Of course, the thickness of the CZT alloy layer in the first magnetic conductive layer 51 and the first isolation layer 512 can also be within other ranges.

[0082] Combination Figure 8 The shielding principle of the first magnetic conductive layer 51 can be understood as follows: since the first magnetic conductive layer 51 is formed by stacking multiple layers, Figure 8 The black line with an arrow represents the propagation direction of the electromagnetic wave, and the thickness of the black line with an arrow represents the radiation energy of the electromagnetic wave. Figure 8 It can be seen that when the electromagnetic wave propagates through the first magnetic conductive layer 51, reflection will be formed at the interface between the CZT alloy layer 511 and the first isolation layer 512. In this way, after multiple reflections, the propagation path of the electromagnetic wave will be extended, thereby increasing the absorption of the electromagnetic wave and improving the shielding effect.

[0083] In an optional embodiment, the total thickness of the second magnetic conductive layer 52 is approximately 1 μm to 20 μm, the thickness of each NiFe alloy layer 521 is approximately 100 nm to 500 nm, and the thickness of each first isolation layer 512 is 1 nm to 10 nm. Of course, the thickness of the NiFe alloy layer and the second isolation layer in the second magnetic conductive layer 52 can also be within other ranges.

[0084] Combination Fig.10 The shielding principle of the second magnetic conductive layer 52 can also be understood as follows: since the second magnetic conductive layer 52 is formed by stacking a plurality of layers, when the electromagnetic wave propagates through the second magnetic conductive layer 52, a reflection will be formed at the interface between the NiFe layer 521 and the second isolation layer 522. In this way, after multiple reflections, the propagation path of the electromagnetic wave will be extended, thereby increasing the absorption of the electromagnetic wave and improving the shielding effect.

[0085] At the same time, because the two materials have ferromagnetic resonance FMR in different frequency bands, they can achieve a wider range of electromagnetic wave absorption. Not only does it have a good shielding effect on high-frequency (greater than 500MHz) electromagnetic waves, it will also improve the shielding effect on low-frequency (less than 500MHz) electromagnetic waves.

[0086] In addition, since each adjacent CZT alloy layer 511 and each adjacent NiFe alloy layer 521 are separated by an isolation layer, the eddy current generated by the electromagnetic wave flows in the plane where the CZT alloy layer is located and the plane where the NiFe alloy layer is located, thereby generating a reverse magnetic field to offset or absorb electromagnetic interference and improve the shielding effect.

[0087] Because the magnetic permeability of NiFe material is lower than that of CZT material, the thickness of each NiFe alloy layer is designed to be thinner (for example, the thickness of each CZT alloy layer 511 is approximately 1μm to 5μm, and the thickness of each NiFe alloy layer 521 is approximately 100nm to 500nm). In this way, the number of stacked NiFe alloy layers can be increased, and the number of reflections can be increased to further extend the propagation path of the electromagnetic wave, further increase the absorption of the electromagnetic wave, and improve the shielding effect.

[0088] Therefore, the shielding effect (Shielding Effect, SE) of the shielding structure provided in the embodiment of the present application is equal to the surface reflection loss (Reflection loss) + absorption loss (Absorption Loss) + multiple internal reflection loss (Multiple internal reflection loss), which increases the loss of electromagnetic waves to improve the shielding effect. Among them, the surface reflection loss (Reflection loss) refers to the loss generated at the interface between two different media, for example, at the interface between the CZT alloy layer and the first isolation layer, the absorption loss (Absorption Loss) refers to the absorption loss generated in the CZT alloy layer or the NiFe alloy layer, and the multiple internal reflection loss (Multiple internal reflection loss) refers to the multiple reflection loss generated between two adjacent isolation layers.

[0089] In the CZT alloy layer, the atomic ratio of Co, Zr and Ta is 90%:5%:5%, or the atomic ratio of Co, Zr and Ta is 91.5%:4%:4.5%. The atomic ratio of Co, Zr and Ta can also be selected from other ratios.

[0090] In the NiFe alloy layer, the atomic ratio of Ni to Fe is 80%:20%, or the atomic ratio of Ni to Fe is 81%:19%. The atomic ratio of Ni to Fe may also be other ratios.

[0091] The stacking method of the first magnetic conductive layer 51 and the second magnetic conductive layer 52 on the plastic packaging layer 3 can be as follows: Fig.11 As shown, the first magnetic conductive layer 51 is attached to the surface of the plastic sealing layer 3, and the second magnetic conductive layer 52 is located on the side of the first magnetic conductive layer 51 away from the plastic sealing layer 3. Fig.13 As shown, the second magnetic conductive layer 52 is attached to the surface of the plastic packaging layer 3 , and the first magnetic conductive layer 51 is located on the side of the second magnetic conductive layer 52 away from the plastic packaging layer 3 .

[0092] Since the CZT material in the first magnetic conductive layer 51 is generally an amorphous thin layer material with relatively small stress, and the NiFe material in the second magnetic conductive layer 52 is generally a polycrystalline thin layer material with relatively large stress. If the second magnetic conductive layer 52 is first formed on the plastic sealing layer 3, the large stress of the NiFe material will cause the thin layer to fall off, affecting the quality of the final product. Therefore, the embodiment of the present application can choose to first form the first magnetic conductive layer 51 on the plastic sealing layer 3, and then form the second magnetic conductive layer 52.

[0093] The first isolation layer 512 and the second isolation layer 522 may be insulating layers or conductive layers. For example, the insulating layers may be made of materials such as SiO2, Ta2O, and Al2O3, or the conductive layers may be made of materials such as Cu, Al, Ni, and Ti.

[0094] When a conductive layer is used as an isolation layer, the conductive layer can achieve better electromagnetic interference shielding effect under the premise of achieving multiple reflections. When an insulating layer is used as an isolation layer, the magnetic permeability of the entire shielding structure can be improved, and the shielding effect can also be improved.

[0095] Fig.12 Is adopted Fig.11 The shielding effect comparison diagram of the structure shown in the figure, in which the dotted line represents the shielding effect curve of the prior art using only the metal layer as the shielding structure, and the solid line represents the shielding effect curve of the present application Fig.11 The shielding effect curve of the structure shown in FIG. It can be seen from the figure that when the electromagnetic wave is 10MHz, a 19dB shielding effect is achieved, which is nearly 5dB higher than the existing 14MHz shielding effect. When the electromagnetic wave is 100MHz, a 33dB shielding effect is achieved. It can be seen from the two curves that in the range of 10MHz to 100MHz, the shielding effect of the present application is better than the prior art.

[0096] In order to further expand the frequency range of shielded electromagnetic waves and improve the low-frequency shielding effect, the present application also provides a shielding structure, combined with Fig.14 In addition to the composite magnetic conductive layer, the metal layer 4 is also included. The metal layer 4 can be made of copper material, stainless steel material, or other non-magnetic metal material. The present application does not limit the material of the metal layer 4.

[0097] The relative positions of the metal layer 4 and the composite magnetic conductive layer can be in two situations, for example: Fig.14 As shown, the metal layer 4 is located between the composite magnetic conductive layer and the plastic sealing layer 3. On this basis, if the first magnetic conductive layer 51 of the composite magnetic conductive layer is close to the plastic sealing layer 3, the metal layer 4 is located between the first magnetic conductive layer 51 and the plastic sealing layer 3. The metal layer 4 located on the side of the plastic sealing layer 3 can extend to the side of the substrate 2 and be electrically connected to the ground layer 201. For another example, Fig.15 As shown, the metal layer 4 is located on the side of the composite magnetic conductive layer away from the plastic packaging layer 3 . When the first magnetic conductive layer 51 of the composite magnetic conductive layer is close to the plastic packaging layer 3 , the metal layer 4 is located on the side of the second magnetic conductive layer 52 away from the first magnetic conductive layer 51 .

[0098] In order to further improve the shielding effect of low frequency, the present application also provides a shielding structure, such as Fig.16 As shown, in addition to the composite magnetic conductive layer mentioned above, the plastic encapsulation layer 3 is doped with soft magnetic material particles 6, wherein the soft magnetic material is a soft magnetic alloy material. For example, the soft magnetic material is a nickel-iron (NiFe) alloy, an iron-silicon-chromium (FeSiCr) alloy, or a cobalt-iron (alloy) CoFe, etc. The soft magnetic material particles 6 can be randomly distributed in the plastic encapsulation layer 3.

[0099] Fig.17 The structure of the soft magnetic material particles 6 in the plastic encapsulation layer 3 is shown. The soft magnetic material particles 6 are almost spherical in shape, with an average radial size of 10 μm to 50 μm, and a maximum radial size of no more than 100 μm. Furthermore, the average radial size of the soft magnetic material particles 6 is 20 μm to 30 μm, and further, the average radial size of the soft magnetic material particles 6 is about 25 μm. The soft magnetic material particles 6 incorporated in the plastic encapsulation layer 3 not only have the effect of absorbing low-frequency electromagnetic waves, but also can achieve reflection, thereby obtaining an interference shielding effect in a wider frequency range, thereby improving the shielding effect of low-frequency electromagnetic waves.

[0100] In addition, when spherical soft magnetic material particles 6 are added into the plastic packaging layer 3, due to the good fluidity of the spherical structure, the plastic packaging layer 3 mixed with the resin material of the plastic packaging layer 3 forms a uniform film after stirring, and the stress concentration of the plastic packaging layer 3 mixed with the spherical soft magnetic material particles 6 is small and the strength is higher, which will further improve the strength of the entire electronic circuit package.

[0101] like Fig.16 and Fig.18 , it is possible that the first soft magnetic material particle 601 in the soft magnetic material particles is electrically connected to the first electronic device 11, the second soft magnetic material particle 602 is electrically connected to the second electronic device 12, and the first soft magnetic material particle 601 is in contact with the second soft magnetic material particle 602. Since the soft magnetic material is a soft magnetic alloy material, in this case, the first electronic device 11 and the second electronic device 12 will cause a short circuit of the device. However, in the circuit structure, it is not necessary to electrically connect the first electronic device 11 and the second electronic device 12. Therefore, referring to Fig.17 The present application further comprises an insulating layer 7, which is wrapped around the outside of the soft magnetic material particles. In this way, electrical isolation of two contacting soft magnetic material particles can be achieved.

[0102] The insulating layer 7 can be made of oxides of metal materials such as Ni, Fe, etc., or can be made of nitride or phosphide.

[0103] The insulating layer 7 here only serves as an insulating structure, so the insulating layer can be set to be relatively thin. For example, the thickness of the insulating layer 7 can be 1 nm to 10 nm.

[0104] Fig.19 Is adopted Fig.16 The shielding effect comparison diagram of the structure shown in the figure, in which the dotted line represents the shielding effect curve of the prior art using only the metal layer as the shielding structure, and the solid line represents the shielding effect curve of the present application Fig.16 The shielding effect curve of the structure shown in FIG. It can be seen from the figure that when the electromagnetic wave is 10MHz, a 28dB shielding effect is achieved, which is about 14dB higher than the existing 14MHz shielding effect. When the electromagnetic wave is 100MHz, a 43dB shielding effect is achieved. It can be seen from the two curves that in the range of 10MHz to 100MHz, the shielding effect of the present application is significantly better than the prior art.

[0105] In the plastic packaging layer 3 doped with the soft magnetic material particles 6, the volume ratio of the soft magnetic material particles 6 can be selected within the range of 1% to 10%. Of course, the volume ratio can also be adjusted and is not limited to the above range.

[0106] Fig. 20 Another shielding structure is shown, in which not only soft magnetic material particles 6 are mixed into the plastic packaging layer 3, but also the surface of the plastic packaging layer is covered with a metal layer 4, and a first magnetic conductive layer 51 and a second magnetic conductive layer 52 are stacked on the surface of the metal layer 4, and the metal layer is electrically connected to the ground layer 201.

[0107] Fig.21 What is shown is another shielding structure, in which not only soft magnetic material particles 6 are doped into the plastic packaging layer 3, but also a first magnetic conductive layer 51 and a second magnetic conductive layer 52 are stacked on the surface of the plastic packaging layer, and a metal layer 4 is covered on the surface of the second magnetic conductive layer 52, and the first magnetic conductive layer 51 is electrically connected to the ground layer 201.

[0108] Fig. 22 Another shielding structure is shown, in which soft magnetic material particles 6 are doped into the plastic packaging layer 3 , and the surface of the plastic packaging layer 3 is covered with a metal layer 4 , which is electrically connected to the grounding layer 201 .

[0109] Fig.23 Is adopted Fig. 22 The shielding effect comparison diagram of the structure shown in the figure, in which the dotted line represents the shielding effect curve of the prior art using only the metal layer as the shielding structure, and the solid line represents the shielding effect curve of the present application Fig. 22The shielding effect curve of the structure shown in FIG. It can be seen from the figure that when the electromagnetic wave is 10MHz, a 22dB shielding effect is achieved, which is nearly 10dB higher than the existing 12MHz shielding effect. When the electromagnetic wave is 100MHz, a 36dB shielding effect is achieved. It can be seen from the two curves that in the range of 10MHz to 1000MHz, the shielding effect of the present application is significantly better than the prior art.

[0110] The present application also provides a method for preparing an electronic circuit package. Fig.24 , the method comprises the following steps:

[0111] S1: forming a plastic encapsulation layer on the surface of a substrate having an electronic device, so that the plastic encapsulation layer wraps the electronic device.

[0112] The electronic device may be an active device, a passive device, or a chip integrating active devices and passive devices.

[0113] S2: A composite magnetic conductive layer is formed on the surface of the plastic sealing layer, wherein the composite magnetic conductive layer includes a first magnetic conductive layer and a second magnetic conductive layer stacked together, and the first magnetic conductive layer includes a plurality of stacked cobalt-zirconium-tantalum alloy layers, and the second magnetic conductive layer includes a plurality of stacked nickel-iron alloy layers, and an isolation layer is provided between every two adjacent cobalt-zirconium-tantalum alloy layers and between every two adjacent nickel-iron alloy layers.

[0114] The electronic circuit package obtained by the preparation method includes multiple stacked cobalt-zirconium-tantalum alloy layers and multiple stacked nickel-iron alloy layers. The cobalt-zirconium-tantalum alloy and the nickel-iron alloy have different magnetic permeability ranges and frequency characteristic ranges, which can achieve absorption of electromagnetic waves in a wider range to enhance the shielding effect of low-frequency electromagnetic waves.

[0115] In addition, since there is an isolation layer between every two adjacent cobalt-zirconium-tantalum alloy layers and an isolation layer between every two adjacent nickel-iron alloy layers, multiple reflections will be formed in the composite magnetic conductive layer, thereby increasing the propagation path of the electromagnetic wave, increasing the reflection loss and absorption loss, and further improving the shielding effect of low-frequency electromagnetic waves.

[0116] When executing the above step S2, it specifically includes:

[0117] A cobalt-zirconium-tantalum alloy layer and an isolation layer are stacked in sequence on the surface of the plastic packaging layer, and this step is repeated to form a first magnetic conductive layer.

[0118] A nickel-iron alloy layer and an isolation layer are sequentially stacked on the surface of the first magnetic conductive layer, and this step is repeated to form a second magnetic conductive layer.

[0119] When forming the cobalt-zirconium-tantalum alloy layer, the nickel-iron alloy layer, and the isolation layer, a sputtering process, an electroplating process, or a coating process may be used.

[0120] In some optional implementations, in order to further improve the shielding effect of low-frequency electromagnetic waves, forming a plastic encapsulation layer on the surface of the substrate having the electronic device specifically includes:

[0121] Soft magnetic material particles are added into the plastic packaging material. The soft magnetic material is a soft magnetic alloy material, such as NiFe, FeSiCr, or CoFe, and an insulating layer is formed on the surface of the soft magnetic material particles. It can be an oxide layer, a nitride layer or a phosphide layer. The insulating layer can be an oxide, a nitride or a phosphide of a metal material such as Ni, Fe, etc.

[0122] A molding material doped with soft magnetic material particles is formed on the surface of the substrate to form a molding layer containing soft magnetic material particles.

[0123] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0124] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An electronic circuit package, characterized in that: include: A substrate having a ground layer formed thereon; An electronic device is arranged on the surface of the substrate; A plastic packaging layer, covering the surface of the substrate and wrapping the electronic device; A composite magnetic conductive layer at least covers the upper surface of the plastic sealing layer; The composite magnetic conductive layer includes a stacked first magnetic conductive layer and a second magnetic conductive layer, the first magnetic conductive layer includes a plurality of stacked cobalt-zirconium-tantalum alloy layers, the second magnetic conductive layer includes a plurality of stacked nickel-iron alloy layers, and an isolation layer is provided between each two adjacent cobalt-zirconium-tantalum alloy layers and between each two adjacent nickel-iron alloy layers.

2. The electronic circuit package according to claim 1, characterized in that: The first magnetic conductive layer is attached to the surface of the plastic sealing layer, and the second magnetic conductive layer is located on a side of the first magnetic conductive layer away from the plastic sealing layer.

3. The electronic circuit package according to claim 1 or 2, characterized in that: The composite magnetic conductive layer covers the surface of the plastic packaging layer except the surface in contact with the substrate, and the composite magnetic conductive layer is electrically connected to the ground layer.

4. The electronic circuit package according to claim 1 or 2, characterized in that: The electronic circuit package further comprises: The metal layer is arranged between the composite magnetic conductive layer and the plastic encapsulation layer, or arranged on a side of the composite magnetic conductive layer away from the plastic encapsulation layer.

5. The electronic circuit package according to claim 3, characterized in that: The electronic circuit package further comprises: The metal layer is arranged between the composite magnetic conductive layer and the plastic encapsulation layer, or arranged on a side of the composite magnetic conductive layer away from the plastic encapsulation layer.

6. The electronic circuit package according to claim 1 or 2, characterized in that: The plastic packaging layer is doped with soft magnetic material particles, the soft magnetic material is a soft magnetic alloy material, and the outside of the soft magnetic material particles is covered by an insulating layer.

7. The electronic circuit package according to claim 3, characterized in that: The plastic packaging layer is doped with soft magnetic material particles, the soft magnetic material is a soft magnetic alloy material, and the outside of the soft magnetic material particles is covered by an insulating layer.

8. The electronic circuit package according to claim 4, characterized in that: The plastic packaging layer is doped with soft magnetic material particles, the soft magnetic material is a soft magnetic alloy material, and the outside of the soft magnetic material particles is covered by an insulating layer.

9. The electronic circuit package according to claim 6, characterized in that: The soft magnetic material is a nickel-iron alloy, an iron-silicon-chromium alloy, or a cobalt-iron alloy.

10. The electronic circuit package according to claim 6, characterized in that: The average radial size of the soft magnetic material particles is 10 μm-50 μm.

11. The electronic circuit package according to claim 1 or 2, characterized in that: The isolation layer is a conductive layer or an insulating layer.

12. The electronic circuit package according to claim 1 or 2, characterized in that: The magnetic permeability of the first magnetic conductive layer is 100-2000, and the electrical conductivity of the first magnetic conductive layer is 50uΩ·cm-200uΩ·cm; and / or; The magnetic permeability of the second magnetic conductive layer is 100-600, and the electrical conductivity of the first magnetic conductive layer is 1 uΩ·cm-50 uΩ·cm.

13. An electronic circuit package, characterized in that: include: A substrate having a ground layer formed thereon; An electronic device is arranged on the surface of the substrate; A plastic encapsulation layer covers the surface of the substrate and wraps the electronic device, wherein the plastic encapsulation layer is doped with soft magnetic material particles, wherein the soft magnetic material is a soft magnetic alloy material, and the outside of the soft magnetic material particles is coated with an insulating layer; A metal layer, covering the surface of the plastic packaging layer and electrically connected to the ground layer; A composite magnetic conductive layer is arranged between the plastic encapsulation layer and the metal layer, or arranged on a side of the metal layer away from the plastic encapsulation layer; The composite magnetic conductive layer comprises a first magnetic conductive layer and a second magnetic conductive layer stacked together, wherein the first magnetic conductive layer comprises a plurality of stacked cobalt-zirconium-tantalum alloy layers, and the second magnetic conductive layer comprises a plurality of stacked nickel-iron alloy layers, and an isolation layer is provided between each two adjacent cobalt-zirconium-tantalum alloy layers and between each two adjacent nickel-iron alloy layers; When the composite magnetic conductive layer is disposed between the plastic sealing layer and the metal layer, the first magnetic conductive layer is attached to the surface of the plastic sealing layer, and the second magnetic conductive layer is located on a side of the first magnetic conductive layer away from the plastic sealing layer; When the composite magnetic conductive layer is arranged on a side of the metal layer away from the plastic packaging layer, the first magnetic conductive layer is attached to the surface of the metal layer, and the second magnetic conductive layer is located on a side of the first magnetic conductive layer away from the metal layer.

14. The electronic circuit package according to claim 13, characterized in that: The soft magnetic material is a nickel-iron alloy, an iron-silicon-chromium alloy, or a cobalt-iron alloy.

15. The electronic circuit package according to claim 13 or 14, characterized in that: The average radial size of the soft magnetic material particles is 10 μm-50 μm.

16. The electronic circuit package according to claim 13 or 14, characterized in that: When the composite magnetic conductive layer is disposed between the plastic encapsulation layer and the metal layer, the remaining surface of the plastic encapsulation layer except the surface in contact with the substrate is covered with the composite magnetic conductive layer, and the composite magnetic conductive layer is electrically connected to the ground layer; When the composite magnetic conductive layer is arranged on a side of the metal layer away from the plastic packaging layer, the remaining surface of the metal layer except the surface in contact with the substrate is covered with the composite magnetic conductive layer.

17. The electronic circuit package according to claim 13 or 14, characterized in that: The isolation layer is a conductive layer or an insulating layer.

18. An electronic device, characterized in that: include: Printed circuit boards; The electronic circuit package as claimed in any one of claims 1 to 17; The electronic circuit package is electrically connected to the printed circuit board.

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