Fillers for encapsulation materials and their preparation methods, magnetic molding materials and encapsulation devices

Abstract

This application provides a filler for an encapsulation material and its preparation method, a magnetic molding compound, and an encapsulation device. The filler for the encapsulation material includes ferrite particles, wherein the ferrite particles include nickel-copper-zinc ferrite (Ni... a Zn b Cu c Fe d The O4 material has the following properties: a ranges from 0.3 to 0.55, b ranges from 0.45 to 0.55, c ranges from 0 to 0.2, and d ranges from 1.8 to 2. The ferrite particles have a particle size of 2-11 μm, accounting for 50-70% of the total. This filler has advantages such as low relative density, wide absorption bandwidth, and good high and low temperature performance, thereby reducing the overall weight of the packaged device and improving its electromagnetic interference resistance and applicable temperature range.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of packaging, in particular to a filler of packaging material and a preparation method thereof, a magnetic plastic packaging material and a packaged device. BACKGROUND

[0002] With the development of electronic technology, the development of integrated circuits and electronic products presents a highly integrated and micro-wiring trend, and chips also present a large-scale, high-power, high-precision and multi-functional development trend. As a result, due to the reduction of distance and the increase of power between various functional modules in the integrated circuit, the electromagnetic interference problem between the functional modules is increasingly serious. Therefore, in order to reduce the electromagnetic interference between the functional modules, higher requirements are needed for electronic packaging. One of the existing solutions is to add ferrite, such as iron oxide powder, to the plastic sealing resin, and then mix and stir uniformly to obtain the required magnetic plastic packaging material. As a traditional magnetic wave-absorbing material, iron oxide has the problems of high relative density, narrow absorption frequency band, poor particle dispersion, poor high-low temperature performance, etc., which can easily cause the overall quality of the packaged device to be high, and can easily make the electromagnetic interference frequency band and the applicable temperature range of the packaged device too narrow, which is not suitable for wide frequency band and large temperature difference application environment. SUMMARY

[0003] The present application provides a filler of packaging material and a preparation method thereof, a magnetic plastic packaging material and a packaged device, so as to reduce the density of the magnetic packaging material, improve its absorption frequency band and high-low temperature performance, and thus reduce the overall quality of the packaged device and improve the electromagnetic interference frequency band and the applicable temperature range of the packaged device.

[0004] In a first aspect, the present application provides a filler of packaging material, which comprises ferrite particles, the ferrite particles comprising a nickel-copper-zinc ferrite (Ni a Zn b Cu c Fe d O4) material, wherein the value range of a is 0.3-0.55, the value range of b is 0.45-0.55, the value range of c is 0-0.2, and the value range of d is 1.8-2; in the ferrite particles, the number fraction of particles with a particle size of 2-11 μm is 50-70%.

[0005] The filler of the present application contains a nickel-copper-zinc ferrite (Ni a Zn b Cu c Fe dThe ferrite material of O4 is used, and the number of particles with a particle size of 2-11 μm in the ferrite particles is limited to 50-70%, so that the obtained filler has good magnetic loss performance between 0.5-6 GHz, the absorption frequency band of the filler is widened, and the packaging device using the filler has a wider anti-electromagnetic interference frequency band. In addition, experiments prove that the filler of the present application can provide anti-interference ability in a wider temperature range (such as -40℃-125℃), so that the packaging device using the filler has a wider applicable temperature, and the anti-magnetic performance of the packaging device is prevented from being greatly attenuated due to temperature change.

[0006] In an alternative implementation, the real part of the magnetic permeability of the filler is in the range of 2-5, and the imaginary part of the magnetic permeability of the filler is in the range of 1.5-2. In an alternative implementation, the wave absorption frequency band of the filler is 0.5-6 GHz. Thus, the filler can have the advantages of high magnetic permeability and wide wave absorption range.

[0007] In an alternative implementation, the mass percentage of the ferrite particles in the filler is greater than or equal to 70%.

[0008] In an alternative implementation, the filler further includes an auxiliary material, and the particle size of the auxiliary material is 0.6-2 μm. The auxiliary material can be a non-magnetic material, and the use of a non-magnetic auxiliary material with a particle size of 0.6-2 μm can help improve the flowability of the ferrite.

[0009] In an alternative implementation, the auxiliary material includes at least one of the following elements: silicon, aluminum or beryllium. The silicon, aluminum or beryllium can exist in the filler in the form of an oxide.

[0010] In a second aspect, the present application provides a filler of a packaging material, which includes ferrite particles, and the number of particles with a particle size of 2-11 μm in the ferrite particles is 50-70%. The ferrite particles include the following raw material components in terms of molar percentage: 15%-27.5% of nickel oxide, 22.5%-27.5% of zinc oxide, and the rest includes diiron trioxide.

[0011] In the filler of the present application, the ferrite particles are the main component of the ferrite particles formed by NiO, ZnO and Fe2O3. By controlling the Ni / Zn ratio, the anisotropy of the ferrite particles can be adjusted. The ferrite particles of the present application are matched by specific components of NiO, ZnO and Fe2O3, and the number of particles with a particle size of 2-11 μm in the ferrite particles is limited to 50-70%. The filler containing the ferrite particles has good magnetic loss performance between 0.5-6 GHz under the premise of meeting the basic mechanical properties, electrical properties, thermal properties and processability of the plastic packaging material, widens the absorption frequency band of the filler, and makes the packaging device using the filler have a wider anti-electromagnetic interference frequency band. In addition, experiments have proved that the filler of the present application can provide anti-interference ability in a wider temperature range, so that the packaging device using the filler has a wider applicable temperature, avoiding a large amplitude attenuation of the anti-magnetic performance of the packaging device due to temperature change.

[0012] In an alternative implementation, the raw material components of the ferrite particles further include copper oxide. By increasing the Cu content, the grain size of the ferrite can be increased, and the sintering density can be improved, thereby further adjusting the magnetic properties of the ferrite.

[0013] In an alternative implementation, the sum of the molar content of the copper oxide and the molar content of the nickel oxide is 15%-27.5%. In an alternative implementation, the molar content of the copper oxide is 7.5%-10%. In an alternative implementation, the molar content of the nickel oxide is 15%-17.5%. The minimum molar content of the NiO can be 15%, and the ferrite particles of this component can have good resistance performance, and the resistivity can be greater than or equal to 1×10 13 Ω·cm, and has a low thermal expansion coefficient and good magnetic loss performance in a wide frequency band of 0.5-6 GHz.

[0014] In an alternative implementation, the mass percentage of the ferrite particles in the filler is greater than or equal to 70%. In an alternative implementation, the filler further includes an auxiliary material, and the particle size of the auxiliary material is 0.6-2 μm. The auxiliary material includes at least one of, but is not limited to, silicon dioxide, aluminum oxide, and beryllium oxide.

[0015] In a third aspect, the present application provides a preparation method of the filler of the present application, which comprises:

[0016] The mixed raw materials containing a nickel source, a zinc source, an iron source and an optional copper source are sequentially sintered and crushed to obtain the ferrite particles; in the ferrite particles, the number of particles with a particle size of 2-11 μm accounts for 50-70%;

[0017] After mixing the ferrite and the auxiliary material, a filler of the encapsulating material is obtained.

[0018] The ferrite obtained by the preparation method has similar properties to the ferrite of the first aspect of the application, and specific properties can be referred to the description of the ferrite of the first aspect of the application, which is not repeated here.

[0019] In an alternative implementation, the mixed raw materials further include the steps of primary ball milling, pre-sintering and secondary ball milling before sintering.

[0020] In an alternative implementation, the time of the primary ball milling is 3-4h. Through the primary ball milling, the raw materials can form small particles with certain assembly, the specific surface area of the particles of the raw materials can be increased, the reactivity of the raw materials in the pre-sintering process can be improved, and the solid phase reaction can be promoted.

[0021] In an alternative implementation, the temperature of the pre-sintering is 800-920℃, and the time of the pre-sintering is 4-6h. Through the pre-sintering, the preliminary solid phase reaction of the oxides of the raw materials can occur, the shrinkage rate of the material in the sintering can be reduced, the compressibility of the material can be improved, and the performance of the ferrite can be improved.

[0022] In an alternative implementation, the time of the secondary ball milling is 10-12h. Through the secondary ball milling, the pre-sintered material with uneven grain size distribution and incomplete solid phase reaction can be finely ground, and the powder particle size required for molding can be obtained. At the same time, the secondary ball milling can further separate the pre-sintered material, increase the surface area of the particles, achieve the required contact surface in the sintering, improve the sintering activity, and promote the densification and grain growth of the product.

[0023] In an alternative implementation, the temperature of the sintering is 920-950℃, and the time of the sintering is 4-6h. Through the sintering process, the solid phase reaction of the secondary ball-milled material can occur, the internal particles can be bonded to each other, the gas can be discharged, and the density and properties of the material can be improved.

[0024] In an alternative implementation, the preparation method further includes the step of crushing the sintered material, and the particle size D50 of the obtained ferrite after crushing is 3.5-7μm. The ferrite with this particle size is more conducive to improving the dispersibility of the ferrite.

[0025] In a fourth aspect, the application provides a magnetic plastic encapsulating material, which includes a plastic encapsulating resin and the filler of the third aspect of the application, and the mass fraction of the filler in the magnetic plastic encapsulating material is 75%-92%.

[0026] The magnetic plastic packaging material of the present application can be used for packaging of chips, radio frequency modules or electronic components to improve the anti-electromagnetic interference capability of the chips, radio frequency modules or electronic components.

[0027] In a fifth aspect, the present application provides a packaged device, which is packaged by the magnetic plastic packaging material of the fourth aspect of the present application. The packaged device includes but is not limited to a chip, a radio frequency module or an electronic component.

[0028] The technical effects achieved by the third aspect and the fifth aspect can be referred to the corresponding effect description of the first aspect, which will not be repeated here.

[0029] In the above possible implementation manners of the present application, the data such as the molar percentage of each component, the particle size of the ferrite, the temperature, the time and other data should be understood as being within the range defined by the present application within the range of engineering measurement error. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 Structure schematic diagram of a packaged device of an embodiment;

[0031] Figure 2 Preparation process flow chart of the magnetic plastic packaging material of an embodiment;

[0032] Figure 3 Structure schematic diagram of the magnetic plastic packaging material of an embodiment;

[0033] Figure 4 Real part test diagram of the magnetic permeability of the magnetic plastic packaging material of embodiment 1;

[0034] Figure 5 Imaginary part test diagram of the magnetic permeability of the magnetic plastic packaging material of embodiment 1.

[0035] Corresponding reference signs:

[0036] 10 - packaged device; 11 - packaging shell;

[0037] 20 - magnetic plastic packaging material; 21 - ferrite particle; 22 - auxiliary material particle; 23 - plastic packaging resin. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings.

[0039] The terminology used in the following description merely for the purpose of describing particular embodiments and is not intended to limit the application. As used in this description and the accompanying claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0040] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. Thus, the appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," and the like in various places throughout this specification are not necessarily referring to the same embodiment, unless otherwise expressly specified. The terms "including," "comprising," "having," and variations thereof are meant to encompass the items listed thereafter, but do not exclude other items from being present.

[0041] Magnetic wave-absorbing material: refers to a magnetic material that absorbs or significantly weakens electromagnetic waves received on its surface to reduce electromagnetic wave interference.

[0042] Permeability: the relative permeability actually tested in engineering applications, which is the ratio of the absolute permeability of a substance to the magnetic constant (also known as the vacuum permeability), while the absolute permeability refers to the ratio of the magnetic induction intensity of a magnetic material to the magnetic field intensity.

[0043] Wave-absorbing frequency band: the electromagnetic wave frequency range of a wave-absorbing material that can absorb or weaken electromagnetic wave energy.

[0044] Moles: a unit of the amount of substance, which is the ratio of the mass of a substance to the molar mass of the substance.

[0045] Existing magnetic wave-absorbing materials, such as ferrite, have a relatively large relative density, which is not conducive to reducing the overall weight of the packaged device. In addition, the absorption frequency band is narrow, and the anti-interference ability of electromagnetic waves of different frequency bands is poor, thereby making the application range of the packaged device single and reducing the frequency band application range. Furthermore, the high and low temperature performance of ferrite is poor, and the anti-interference performance will be significantly reduced when applied at high and low temperatures.

[0046] To solve the above technical problems, the application provides a filler for packaging material. The filler of the embodiment of the application comprises ferrite particles, and the ferrite particles comprise a molecular formula of Ni a Zn b Cu c Fe dThe material of O4, wherein O is oxygen, the number of atoms of O in the molecular formula of the ferrite particle is 4; Ni is nickel, the value range of a is 0.3-0.55; Zn is zinc, the value range of b is 0.45-0.55; Cu is copper, the value range of c is 0-0.2; Fe is iron, the value range of d is 1.8-2; wherein, the "molecular formula" is understood as the element composition of the ferrite. In an embodiment, in the particle of the ferrite, the number of particles with a particle size of 2-11 μm accounts for 50-70%.

[0047] The filler with the above-mentioned molecular formula can have a magnetic permeability real part of 2-5 and a magnetic permeability imaginary part of 1.5-2. Meanwhile, the ferrite can have a wave absorption frequency band of 0.5-6 GHz.

[0048] In the particle of the ferrite of the embodiment, the number of particles with a particle size of 2-11 μm accounts for 50-70%. Exemplarily, the number of particles with a particle size of 2-11 μm can account for 50%-55%, 55%-60%, 60%-65% or 65%-70%.

[0049] In order to improve the forming performance of the filler, in an alternative embodiment, the filler further comprises an auxiliary material. In an embodiment, the auxiliary material can be a non-magnetic material. In an embodiment, the auxiliary material can be in a particle form. The proportion of the ferrite particles in the filler is greater than or equal to 70% and the proportion of the auxiliary material is less than or equal to 30% based on the mass of the filler. In an embodiment, the auxiliary material can comprise at least one of the following elements: silicon Si, and / or aluminum Al, and / or beryllium Bi. Silicon, aluminum or beryllium can exist in the filler in the form of an oxide. The particle size of the auxiliary material can be 0.6-2 μm. By adding the auxiliary material with a specific particle size, the flowability of the ferrite can be improved, and in turn the dispersibility of the ferrite particles can be improved, that is, the uniformity of the ferrite particles in the filler is improved, and the ferrite particles are more uniformly distributed in the filler.

[0050] Based on the same technical concept, the embodiment of the present application further provides a filler, wherein the filler comprises ferrite particles, and the number of particles with a particle size of 2-11 μm in the ferrite particles accounts for 50-70%; wherein the ferrite particles can comprise the following raw material components: nickel oxide NiO 15 mol%-27.5 mol%, zinc oxide ZnO 22.5 mol%-27.5 mol%, and the rest comprises diiron trioxide Fe2O3. In an embodiment, the filler of the present application can further comprise an auxiliary material in addition to the ferrite particles, for example, can comprise at least one of the following: silicon dioxide SiO2, and / or aluminum trioxide Al2O3, and / or beryllium oxide BiO.

[0051] In some embodiments, the molar percentage of NiO in the ferrite particles is typically but not limited to 15 mol%, 15.5 mol%, 16 mol%, 16.5 mol%, 17 mol%, 17.5 mol%, 18 mol%, 18.5 mol%, 19 mol%, 20 mol%, 21 mol%, 22 mol%, 23 mol%, 24 mol%, 25 mol%, 26 mol%, 27 mol%, or 27.5 mol%, based on the moles of the ferrite particles. In some embodiments, the lower limit of the molar percentage of NiO in the ferrite particles can be any of the above values and an intermediate value between any two of the above values, for example, 15 mol%, 15.5 mol%, 16 mol%, 16.5 mol%, or any two of the above values. In some embodiments, the upper limit of the molar percentage of NiO in the ferrite particles can be any of the above values and an intermediate value between any two of the above values, for example, 17 mol%, 17.5 mol%, 20 mol%, 22 mol%, 24 mol%, 26 mol%, 27.5 mol%, or any two of the above values.

[0052] In some embodiments, the molar percentage of ZnO in the ferrite particles is typically but not limited to 22.5 mol%, 23 mol%, 23.5 mol%, 24 mol%, 24.5 mol%, 25 mol%, 25.5 mol%, 26 mol%, 26.5 mol%, 27 mol%, or 27.5 mol%, based on the moles of the ferrite particles. In some embodiments, the lower limit of the molar percentage of ZnO in the ferrite particles can be any of the above values and an intermediate value between any two of the above values, for example, 22.5 mol%, 23 mol%, 23.5 mol%, 24 mol%, or any two of the above values. In some embodiments, the upper limit of the molar percentage of ZnO in the ferrite particles can be any of the above values and an intermediate value between any two of the above values, for example, 25.5 mol%, 26 mol%, 26.5 mol%, 27 mol%, 27.5 mol%, or any two of the above values.

[0053] In some embodiments, the raw material composition of the ferrite particles can further include CuO. In some embodiments, CuO replaces NiO in the ferrite in an equimolar ratio. When the ferrite particles contain CuO, the minimum molar content of NiO is 15%. That is, when the ferrite contains CuO, the total molar content of CuO and NiO is in the range of 15%-27.5%, and the minimum molar content of NiO is 15%.

[0054] In an alternative embodiment, the molar content of CuO is 7.5-10 mol%. In an alternative embodiment, the ferrite particles comprise the following raw material components in terms of molar percentage: NiO 15-17.5%, ZnO 22.5-27.5%, CuO 7.5-10%, and the rest is Fe2O3. The molar percentage of CuO in the ferrite, based on the number of moles of ferrite particles, is typically but not limited to 7.5 mol%, 8 mol%, 8.5 mol%, 9 mol%, 9.5 mol%, or 10 mol%. Among them, the lower limit of the molar percentage of CuO in the ferrite particles can be any of the above values and the intermediate value of any two values, for example, it can be 7.5 mol%, 7.6 mol%, 7.7 mol%, 7.8 mol%, 7.9 mol%, 8 mol%, or any of the above two values; the upper limit of the molar percentage of CuO can be any of the above values and the intermediate value of any two values, for example, it can be 9 mol%, 9.1 mol%, 9.2 mol%, 9.3 mol%, 9.4 mol%, 9.5 mol%, 9.6 mol%, 9.7 mol%, 9.8 mol%, 9.9 mol%, 10 mol%, or any of the above two values.

[0055] The composition of the filler of the embodiment of the application is explained above, and the preparation method of the filler of the embodiment of the application will be explained below.

[0056] The preparation method of the filler of the embodiment of the application can include the following steps S11-S12:

[0057] S11, the mixed raw materials containing nickel source, zinc source and iron source and optional copper source are sequentially sintered and crushed to obtain the ferrite particles; in the ferrite particles, the number of particles with a particle size of 2-11 μm accounts for 50-70%. Among them, the nickel source is a substance containing nickel element, for example, it can be elemental nickel, nickel oxide, etc. The zinc source can be elemental zinc, zinc oxide, etc. The iron source can be elemental iron, iron oxide, etc.

[0058] S12, the ferrite and the optional auxiliary material are mixed to obtain the filler of the packaging material.

[0059] Among them, the mixed raw materials further include the steps of primary ball milling, pre-sintering and secondary ball milling before sintering.

[0060] Among them, the time of primary ball milling can be 3-4 hours (unit: h). For example, the time of primary ball milling can be 3-3.5 h or 3.5-4 h.

[0061] The pre-sintering temperature is 800-920℃, and the pre-sintering time is 4-6h. Exemplarily, the pre-sintering temperature can be 800℃, 810℃, 820℃, 830℃, 840℃, 850℃, 860℃, 870℃, 880℃, 890℃ or 900℃ or a temperature within any adjacent two numerical ranges of the above; the pre-sintering time can be 4h, 4.5h, 5h, 5.5h or 6h or a time within any adjacent two numerical ranges of the above.

[0062] The secondary ball milling time can be 10-12h. Exemplarily, the secondary ball milling time can be 10h, 11h or 12h or a time within any adjacent two numerical ranges of the above.

[0063] The sintering temperature can be 920-950℃, and the sintering time can be 4-6h. Exemplarily, the sintering temperature can be 920℃, 925℃, 930℃, 935℃, 940℃, 945℃ or 950℃ or a temperature within any adjacent two numerical ranges of the above; the sintering time can be 4h, 4.5h, 5h, 5.5h or 6h or a time within any adjacent two numerical ranges of the above.

[0064] In an embodiment of the present application, the particle size D50 of the ferrite obtained after crushing in the method for preparing ferrite particles is 3.5-7μm.

[0065] Based on the same inventive purpose, the present application further provides a magnetic plastic packaging material, which comprises the filler of the present application, wherein the mass percentage of the filler in the magnetic plastic packaging material is 75%-92%. The magnetic plastic packaging material further comprises a plastic packaging resin, such as an epoxy resin, which serves to bond the filler. The mass percentage of the resin material in the magnetic plastic packaging material can be, for example, 8%-25%. In addition, the magnetic plastic packaging material can further comprise a coupling agent, a reinforcing agent, a pigment and the like.

[0066] Based on the same inventive purpose, the present application further provides a packaging device, Figure 1 As shown in the structural schematic diagram of a packaging device, Figure 1 The packaging device 10 can comprise a packaging shell 11 and a functional device arranged in the packaging shell 11, wherein the packaging shell 11 can be packaged by using the magnetic plastic packaging material of the present application. The packaging device of the present application can have the advantages of light packaging quality, wide applicable frequency band and wide applicable temperature range.

[0067] The ferrite of the present application will be further described in detail below in combination with specific examples and comparative examples.

[0068] Example 1

[0069] The embodiment is a magnetic plastic packaging material, Figure 2 The embodiment is a magnetic plastic packaging material, Figure 3 The embodiment is a magnetic plastic packaging material, Figure 2 And Figure 3 The preparation process of the magnetic plastic packaging material includes the following steps:

[0070] Step S1, providing raw materials: taking NiO, ZnO, CuO and Fe2O3 as raw materials, and the contents are as follows: NiO: 16 mol%, ZnO: 25 mol%, CuO: 9 mol%, and the rest is Fe2O3;

[0071] Step S2, mixing raw materials: the raw materials obtained in step S1 are ball milled for 3-4h, and the slurry obtained after ball milling is placed in an oven for drying. After drying, the powder is broken to obtain a uniformly mixed powder;

[0072] Step S3, the uniformly mixed powder obtained in step S2 is pre-fired at a temperature of 800-920℃ for 4-6h. After natural cooling, the pre-fired material is broken to obtain a pre-fired material;

[0073] Step S4, the pre-fired material obtained in step S3 is subjected to secondary ball milling for 10-12h. The slurry obtained after ball milling is placed in an oven for drying. After drying, the powder is broken and then sintered at a temperature of 920-950℃ for 4-6h. After natural cooling, the ferrite block material is obtained;

[0074] Step S5, the ferrite block material obtained in step S4 is subjected to primary coarse crushing. The coarse crushed powder is made into fine powder by a mechanical crusher, and the particle size distribution D50 is 2-11. Ferrite particles are obtained; wherein the number of particles with a particle size of 2-11μm accounts for 50%.

[0075] Step S6, the ferrite particles 21 obtained in step S5 are mixed with non-ferrite (e.g. fumed silica) particles 22 to obtain a filler, as shown in Figure 3 In the filler, the mass percentage of ferrite particles 21 is 83%, and the mass percentage of fumed silica particles is 17%;

[0076] Step S7, the obtained filler is used as the filler of the magnetic plastic packaging material to prepare the magnetic plastic packaging material: referring to Figure 3 The filler (ferrite particles 21 and non-ferrite particles 22) is mixed with plastic packaging resin 23 and optional additives, etc. by a plastic packaging material preparation process, such as a mold forming process, to obtain a magnetic plastic packaging material 20. In the magnetic plastic packaging material 20, the mass percentage of the filler is 90%, and the total mass percentage of the plastic packaging resin 23 and the additives is 10%.

[0077] Figure 4 The real part of the magnetic permeability test chart of the magnetic plastic sealing material in the embodiment of the application is shown in FIG. 1. Figure 5 The imaginary part of the magnetic permeability test chart of the magnetic plastic sealing material in the embodiment 1 is shown in FIG. 2. The abscissa represents the frequency, and the ordinate represents the magnetic performance. It can be seen from FIG. 2 that the magnetic plastic sealing material has a wide frequency range of 5 GHz, and has a high magnetic performance in the range of 3 GHz, the real part of the magnetic permeability is greater than 2, the imaginary part of the magnetic permeability is greater than 1.5, and the frequency at the peak of the imaginary part of the magnetic permeability is the optimal working frequency. Figure 4 Figure 5 It can be seen that the magnetic plastic sealing material has a wide frequency range of 5 GHz, and has a high magnetic performance in the range of 3 GHz, the real part of the magnetic permeability is greater than 2, the imaginary part of the magnetic permeability is greater than 1.5, and the frequency at the peak of the imaginary part of the magnetic permeability is the optimal working frequency.

[0078] Embodiment 2

[0079] The embodiment is a kind of magnetic plastic sealing material, and the difference from embodiment 1 is that the raw material composition is different, and the raw material composition of ferrite in the magnetic plastic sealing material of this embodiment is as follows: NiO, ZnO, CuO, Fe2O3 are used as raw materials, and the content is as follows, NiO:15mol%, ZnO:27.5mol%, CuO:10mol%, the rest is Fe2O3.The rest of the preparation process refers to embodiment 1.

[0080] Embodiment 3

[0081] The embodiment is a kind of magnetic plastic sealing material, and the difference from embodiment 1 is that the raw material composition is different, and the raw material composition of ferrite in the magnetic plastic sealing material of this embodiment is as follows: NiO, ZnO, CuO, Fe2O3 are used as raw materials, and the content is as follows, NiO:16.5mol%, ZnO:25mol%, CuO:8mol%, the rest is Fe2O3.The rest of the preparation process refers to embodiment 1.

[0082] Embodiment 4

[0083] The embodiment is a kind of magnetic plastic sealing material, and the difference from embodiment 1 is that the particle size of ferrite is different, and in this embodiment, the number of particles with a particle size of 2-11 μm accounts for 70%.

[0084] Comparative Example 1

[0085] The embodiment is a kind of magnetic plastic sealing material, and the difference from embodiment 1 is that the particle size of ferrite is different, and in this embodiment, the number of particles with a particle size of 2-11 μm accounts for 40%.

[0086] Comparative Example 2

[0087] The embodiment is a kind of magnetic plastic sealing material, and the difference from embodiment 1 is that the particle size of ferrite is different, and in this embodiment, the number of particles with a particle size of 2-11 μm accounts for 85%.

[0088] Comparative Example 3​

[0089] The comparative example is a magnetic plastic sealing material, and the raw material composition is as follows: taking NiO, ZnO, CuO and Fe2O3 as raw materials, the contents are as follows, NiO: 10 mol%, ZnO: 15 mol%, CuO: 5 mol%, and the balance is Fe2O3. The rest of the preparation process refers to Example 1.

[0090] Comparative Example 4

[0091] The comparative example is a magnetic plastic sealing material, and the difference from Example 1 is that the raw material composition is different. The raw material composition of the magnetic plastic sealing material of this example is as follows: taking NiO, ZnO, CuO and Fe2O3 as raw materials, the contents are as follows, NiO: 20 mol%, ZnO: 30 mol%, CuO: 15 mol%, and the balance is Fe2O3. The rest of the preparation process refers to Example 1.

[0092] Comparative Example 5

[0093] The example is a magnetic plastic sealing material, and the difference from Example 1 is that the raw material composition is different. The raw material composition of the magnetic plastic sealing material of this example is as follows: taking NiO, ZnO, CuO and Fe2O3 as raw materials, the contents are as follows, NiO: 30 mol%, ZnO: 15 mol%, CuO: 5 mol%, and the balance is Fe2O3. The rest of the preparation process refers to Example 1.

[0094] Comparative Example 6

[0095] The example is a magnetic plastic sealing material, and the difference from Example 1 is that the raw material composition is different. The raw material composition of the magnetic plastic sealing material of this example is as follows: taking NiO, ZnO, CuO and Fe2O3 as raw materials, the contents are as follows, NiO: 10 mol%, ZnO: 25 mol%, CuO: 17 mol%, and the balance is Fe2O3. The rest of the preparation process refers to Example 1.

[0096] The performance parameters of the magnetic plastic sealing materials of each example and comparative example were tested respectively, and the test results are shown in Table 1.

[0097] Table 1

[0098]

[0099]

[0100] As can be seen from the test data in Table 1, the maximum values of the real part and the imaginary part of the magnetic permeability of each magnetic plastic packaging material of the embodiments of the present application are higher than those of Comparative Examples 1-6. It is illustrated that when the ratio of each raw material component in the ferrite is not within the range defined by the present application, the magnetic properties of the corresponding magnetic plastic packaging material cannot achieve the effect of the present application.

[0101] In addition, as can be seen from the comparative data of Example 1, Example 4, Comparative Example 1 and Comparative Example 2, when the number of particles with a particle size of 2-11 μm accounts for 50-70% outside the range, the magnetic loss performance of the obtained magnetic plastic packaging material is slightly lower than that of Example 1 and Example 4, which illustrates that the size of the particle size in the ferrite can affect the magnetic properties of the magnetic plastic packaging material.

[0102] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A filler for encapsulating material, characterized by, Comprise ferrite particles, the ferrite particles comprise nickel copper zinc ferrite material, the chemical formula of the nickel copper zinc ferrite material is Ni a Zn b Cu c Fe d O4, wherein a is 0.3-0.55, b is 0.45-0.55, c is 0-0.2, and d is 1.8-2; In the ferrite particles, the number of particles with a particle size of 2-11 μm accounts for 50-70%.

2. The filler of claim 1, wherein The real part of the magnetic permeability of the filler is 2-5, and the imaginary part of the magnetic permeability of the filler is 1.5-2.

3. The filler of claim 1, wherein The wave absorption frequency band of the filler is 0.5-6 GHz.

4. The filling agent according to any one of claims 1 to 3, characterized in that, The mass proportion of the ferrite particles in the filler is greater than or equal to 70%.

5. The filler of any one of claims 1-3, wherein, The filler further comprises an auxiliary material, and the particle size of the auxiliary material is 0.6-2 μm.

6. The filler of claim 5, wherein, The auxiliary material comprises at least one of the following elements: silicon, aluminum, or beryllium.

7. A filler for encapsulating material, characterized by The ferrite particles comprise, in terms of number proportion, 50-70% of particles with a particle size of 2-11 μm; wherein, The ferrite particles comprise, in terms of molar percentage, the following raw material components: 15%-27.5% of nickel oxide, 22.5%-27.5% of zinc oxide, and the rest comprising diiron trioxide.

8. The filler of claim 7, wherein, The raw material components of the ferrite particles further comprise copper oxide.

9. The filler of claim 8, wherein, The sum of the molar content of the copper oxide and the molar content of the nickel oxide is 15%-27.5%.

10. The filler of claim 8, wherein, The molar content of the copper oxide is 7.5%-10%.

11. The filler of claim 10, wherein, The molar content of the nickel oxide is 15%-17.5%.

12. The filling agent according to any one of claims 7 to 11, characterized in that, The mass proportion of the ferrite particles in the filler is greater than or equal to 70%.

13. The filler of any one of claims 7-11, wherein, The filler further comprises an auxiliary material, and the particle size of the auxiliary material is 0.6-2 μm.

14. The filler of claim 13, wherein, The auxiliary material comprises at least one of the following: silicon dioxide, diiron trioxide, and beryllium oxide.

15. A process for the preparation of a filler as claimed in any one of claims 1 to 14, characterised in that, Comprise: A mixed raw material containing a nickel source, a zinc source, and an iron source, and optionally a copper source, is sequentially sintered and crushed to obtain the ferrite particles; In the ferrite particles, the number proportion of particles with a particle size of 2-11 μm is 50-70%; The ferrite and the optional auxiliary material are mixed to obtain the filler of the packaging material.

16. The method of claim 15, wherein, The mixed raw material further comprises the steps of primary ball milling, pre-sintering, and secondary ball milling before sintering.

17. The method of claim 16, wherein, The primary ball milling time is 3-4 h.

18. The method of claim 16, wherein, The pre-sintering temperature is 800-920 ℃, and the pre-sintering time is 4-6 h.

19. The method of claim 16, wherein, The secondary ball milling time is 10-12 h.

20. The method of any one of claims 15-19, wherein, The sintering temperature is 920-950 ℃, and the sintering time is 4-6 h.

21. The method of any one of claims 15-19, wherein, The particle size D50 of the ferrite particles obtained after crushing is 3.5-7 μm.

22. A magnetic plastic encapsulating material, characterized by, The magnetic plastic packaging material comprises a plastic packaging resin and the filler according to any one of claims 1-12, and the mass proportion of the filler in the magnetic plastic packaging material is 75%-92%.

23. A packaged device, comprising: The packaged device is packaged using the magnetic plastic packaging material according to claim 22.

Images