High-integration-level carrier plate and power supply module

Abstract

The invention discloses a carrier board with high integration level, which comprises at least two prefabricated printed circuit board laminations and at least one hollow area, the printed circuit board laminations are fixedly connected through an insulated bonding dielectric layer, and the hollow area is provided with at least one power supply circuit assembly. On the other hand, the invention discloses a high-integration-level transformer unit and a high-integration-level two-stage framework power supply device. The high-integration-level two-stage framework power supply device comprises an annular magnetic core and a winding, wherein the annular magnetic core is embedded in a carrier plate, and the winding is arranged in the carrier plate. On the other hand, the invention discloses a high-integration-level composite electronic component group which comprises at least two flat component groups which are fixedly connected through a bonding medium layer. The bonding medium layer does not need to play a supporting role, so that the thickness of the bonding medium layer can be far smaller than the thickness of a first lamination layer in a lamination mode, namely far smaller than 0.2 mm, space can be saved, and on the other hand, the lamination layer above the hollow area can be manufactured according to a conventional process, so that the process can be simplified.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-frequency power supply, and in particular relates to a highly integrated carrier board and a power supply module. Background Art

[0002] With the increasing demand for various artificial intelligence and data processing, global computing power consumption has exploded. Moreover, since the size of these computing units is extremely limited, higher and higher requirements are placed on the floor space, height, efficiency, and heat dissipation of energy processing units.

[0003] A typical two-stage power supply architecture, the front stage is 48V to 12V (5V), and the back stage is 12V (5V) to the processor's operating voltage, which is around ~1V. The front stage module usually contains a magnetic component, a transformer, because its voltage conversion is relatively high; the back stage usually uses a buck circuit, which contains a magnetic component, an inductor.

[0004] The following method is generally used in the prior art. First, a first stack including a part of the winding is formed. A hole slot and other structures are opened on the first stack. A magnetic core is arranged in the hole slot structure in a manner similar to the copper embedding process. Then, a carrier with an embedded magnetic core structure is stacked one by one on top of the first stack. On the one hand, the winding on the side of the magnetic core can be realized through a through hole that penetrates the entire carrier. In this case, each turn of the winding needs to be electrically connected to the surface of the carrier, and then further wired through the carrier. On the other hand, it is first formed in the first stack through a through hole and a blind hole, and then connected layer by layer through the blind hole in the process of stacking one by one. Figure 1A The above method has the following technical problems:

[0005] 1. Through holes are used on the sides to connect the windings, and the interference between the layers destroys the integrity of the windings and increases the impedance

[0006] 2. The side uses vias for vertical interconnection, which occupies a large area

[0007] 3. Blind holes are used on the top of the core to connect layer by layer, which increases the cost

[0008] 4. The magnetic core is directly embedded in the substrate, and there is a problem of matching the core material and the substrate. For certain materials, it may cause increased core loss and increased structural reliability risks.

[0009] like Figure 1B As shown, in the process of embedding the magnetic core, a redundant area is left in the hollowed-out part. The advantage of this is that the matching problem between the magnetic core and the carrier board can be solved.

[0010] However, the above methods cannot solve the other three technical problems mentioned above, but also bring new technical problems:

[0011] 5. In order to ensure that subsequent lamination can be realized, the thickness of the first base material medium layer above the first lamination is relatively large, for example, more than 0.2 mm, resulting in a high waste of space.

[0012] On the other hand, when the thickness of the first stack is large, if blind vias are used, the size of the blind via opening will increase in order to meet the requirements of the electroplating width-to-depth ratio. In addition, the problem of sidewall leakage during blind via electroplating needs to be considered, and sufficient safety distance needs to be reserved, which will further waste space. Furthermore, when traditional cavities are stacked layer by layer, when the support is insufficient, it is easy to have problems such as poor interlayer filling and low density, which will cause many reliability risks.

[0013] Therefore, how to achieve the integration of magnetic components and the integration of magnetic components with power devices in a way of high space utilization and high reliability is an issue that needs to be solved urgently. Summary of the invention

[0014] In view of this, the object of the present invention is to provide a highly integrated carrier board and a power module, in which the magnetic structure can be embedded in the carrier board, the thickness of the bonding medium layer can be much smaller than the thickness of the laminated layer, and a vertical section of the winding can be formed by side wall metal parts and outer metal parts, thereby greatly reducing the height of the power module and facilitating heat dissipation, while improving the flexibility of wiring.

[0015] To achieve the above-mentioned objectives, the present invention provides, on one hand, a highly integrated carrier, comprising at least two prefabricated printed circuit board stacks, at least one of the printed circuit board stacks having a first surface, the first surface being provided with at least one hollow area, the hollow area being buried in the carrier, the printed circuit board stacks being fixedly connected by an insulating adhesive medium layer, the carrier being provided with an electrical connector penetrating the adhesive medium layer, and the hollow area being provided with at least one power circuit component.

[0016] Preferably, the power circuit assembly comprises at least one magnetic core, the printed circuit board stack comprises at least a portion of a winding, and the winding and the magnetic core are used to form a magnetic element in the power circuit by cooperating with each other.

[0017] Preferably, at least one of the hollowed-out areas is provided with a sidewall metal piece, and at least one of the sidewall metal pieces is used to form at least a portion of a winding, and the winding and the magnetic core are used to form a magnetic element in a power circuit by cooperating with each other.

[0018] Preferably, an outer side wall of the printed circuit board stack where the side wall metal piece is located is provided with an outer metal piece, and the outer metal piece is used to form at least a part of the winding.

[0019] Preferably, the electrical connector penetrating the bonding medium layer comprises a bonding material piece, and the bonding material piece is made of a non-remelting conductive bonding material, and the non-remelting conductive bonding material will not remelt within 220 degrees Celsius.

[0020] Preferably, the power circuit assembly and the printed circuit board stack are electrically connected via one or more conductive connectors, and the conductive connectors are made of a non-remelting conductive bonding material that will not remelt within 220 degrees Celsius.

[0021] Preferably, the non-remelting conductive bonding material includes at least one of solder, tin-silver alloy, tin-copper alloy, tin-silver-copper alloy, tin-antimony alloy, gold-tin alloy, high-lead solder, silver sintering paste, copper sintering paste, transient liquid phase sintering material or conductive paste.

[0022] Preferably, the electrical connector penetrating the bonding medium layer comprises a via-plating component.

[0023] Preferably, the material of the bonding medium layer includes at least one of a prepreg (Pre-Preg) or an ABF (Ajinomoto Build-up Film).

[0024] Preferably, an insulating filling body is provided in the hollow area, and the insulating filling body covers the power circuit component.

[0025] Preferably, the hollow structure includes at least one step area, and power circuit components of different heights are respectively arranged inside and outside the step area.

[0026] Preferably, at least one of the printed circuit board stacks has a second surface, the second surface does not have a hollow area, a power circuit component is arranged on the second surface, and the power circuit component on the second surface is located in the hollow area opened in another printed circuit board stack.

[0027] Preferably, at least two adjacent printed circuit board stacks are provided with hollow areas, and the corresponding hollow areas are connected.

[0028] Preferably, at least three printed circuit board stacks are provided; at least one of the printed circuit board stacks is penetrated by a hollow area.

[0029] Preferably, at least three printed circuit board stacks are provided; at least two hollow areas are provided; and the hollow areas are respectively opened in different printed circuit board stacks and / or opened on different surfaces of the printed circuit board stack.

[0030] Preferably, the magnetic core is arranged across at least one printed circuit board stack, and a plurality of hollow areas are provided, and the plurality of hollow areas are respectively used to accommodate a portion of the magnetic core.

[0031] Preferably, at least one power circuit component is electrically connected to two different printed circuit board stacks via pins.

[0032] Preferably, an electrical connection semi-counterfeit hole is provided on the printed circuit board stack corresponding to at least one of the pins.

[0033] Preferably, at least one of the pins is a flexible pin.

[0034] Preferably, at least one of the hollowed-out areas is provided with a sidewall metal piece, and at least one of the sidewall metal pieces is used to form a signal shielding layer.

[0035] Preferably, a plurality of the side wall metal pieces are arranged on a side wall of the same hollow area, and the side wall metal pieces extend along the thickness direction of the carrier plate and are arranged in an array along the horizontal direction.

[0036] Preferably, the side wall metal piece is provided with solder at the top or bottom of the hollow area, or the side wall metal piece and the printed circuit board laminate are electrically connected via flying leads.

[0037] On the other hand, the present invention also provides a highly integrated transformer unit, including an annular magnetic core, a primary winding, a secondary winding and a carrier, wherein the carrier includes at least two prefabricated printed circuit board stacks; at least one of the printed circuit board stacks is provided with an annular hollow area for accommodating the annular magnetic core, the printed circuit board stack is wrapped around the annular magnetic core by snapping, and the printed circuit board stacks are fixedly connected by an adhesive medium layer; at least a portion of the primary winding and the secondary winding is arranged in the printed circuit board stack.

[0038] Preferably, one of the primary winding or the secondary winding is arranged on the surface of the annular magnetic core and is electrically connected to the printed circuit board laminate via at least two conductive connectors.

[0039] Preferably, an insulating transition layer is provided between one of the primary winding or the secondary winding and the surface of the annular magnetic core.

[0040] Preferably, an insulating protection layer is further provided on the outer side of one of the primary winding or the secondary winding.

[0041] Preferably, the other of the primary winding or the secondary winding is arranged on a printed circuit board laminate and comprises a first winding and a second winding which are nested inside and outside.

[0042] Preferably, a plurality of side wall metal pieces are arranged in the annular hollow area, the side wall metal pieces extend along the thickness direction of the carrier plate and are arranged in an array along the horizontal direction; the side wall metal pieces are used to form the vertical portion of the first winding.

[0043] Preferably, the outer edge sidewalls of the printed circuit board stack are provided with a plurality of outer metal parts, and the outer metal parts are used to form the vertical parts of the second winding.

[0044] Preferably, the at least two conductive connectors are electrically connected to different printed circuit board stacks respectively.

[0045] Preferably, the primary winding and / or the secondary winding comprises at least three windings nested inside and outside.

[0046] Preferably, vertical via holes are provided in the carrier board, and bonding material pieces are provided in the bonding medium layer at positions corresponding to the vertical via holes. The vertical via holes and bonding material pieces are used to form vertical segments of the primary winding and / or vertical segments of the secondary winding.

[0047] Preferably, a vertical via hole is provided in the carrier board, the vertical via hole penetrates the bonding medium layer, and the vertical via hole is used to form a vertical segment of the primary winding and / or a vertical segment of the secondary winding.

[0048] Preferably, the vertical through hole arranged in the middle of the annular magnetic core is a vertical segment shared by multiple primary windings or a vertical segment shared by multiple secondary windings.

[0049] Preferably, it also includes circuit elements, which include switching elements and / or driving elements and / or capacitor elements and / or controllers; the switching elements include primary switching elements and / or secondary switching elements, the primary switching elements are connected in series with the primary winding, and the secondary switching elements are connected in series with the secondary winding.

[0050] Preferably, the carrier board has a heat dissipation surface; the circuit element is arranged on the heat dissipation surface, and / or the circuit element is arranged in the hollow area and on a surface close to the heat dissipation surface.

[0051] Preferably, the switch elements are arranged in pairs in parallel on two opposite sides of the printed circuit board stack and in corresponding positions, one of the switch elements arranged in pairs in parallel is located in the hollow area, and the other is located on the outer surface of the carrier board.

[0052] Preferably, it further comprises a plastic package, the circuit element is arranged on the outer surface of the carrier, and the plastic package covers the circuit element and the outer surface.

[0053] Preferably, a conductive adapter is provided in the plastic package body, one end of the conductive adapter is electrically connected to the carrier board, and the other end is exposed on the surface of the plastic package body; the conductive adapter is arranged at a position adjacent to the central axis of the transformer unit.

[0054] Another aspect of the present invention provides a highly integrated two-stage power supply device, comprising a two-stage carrier, a front-stage magnetic core, a front-stage winding, a front-stage circuit element and a rear-stage circuit element, wherein the two-stage carrier comprises at least two printed circuit board stacks, and the two-stage carrier is divided into a front-stage element area and a rear-stage element area according to circuit functions, and the front-stage element area is an annular area surrounding the rear-stage remote element area;

[0055] At least one of the printed circuit board stacks has an annular hollow area in the front-stage component area, the front-stage magnetic core is annular, and the front-stage magnetic core is arranged in the annular hollow area;

[0056] The front-stage winding is arranged in the front-stage element area, and at least a part of the front-stage winding is arranged in the printed circuit board stack;

[0057] At least one of the printed circuit board stacks has a middle hollow area in the rear-stage component area, and at least a portion of the rear-stage circuit components are arranged in the middle hollow area;

[0058] The printed circuit board stack is fixedly connected via a bonding medium layer, and the two-stage structure carrier is provided with an electrical connector penetrating the bonding medium layer.

[0059] Preferably, the area of ​​the front-stage component region is smaller than that of the rear-stage component region, that is, the front-stage region is a narrower ring surrounding the rear-stage region with a larger area.

[0060] Preferably, at least a portion of the front-stage circuit elements are disposed on an outer surface of the two-stage structure carrier, and / or at least a portion of the rear-stage circuit elements are disposed on an outer surface of the two-stage structure carrier.

[0061] Preferably, the two-stage structure carrier has a first surface; in the front-stage component area or the back-stage component area of ​​the first surface, the outermost printed circuit board stack is hollowed out to expose the second outer printed circuit board stack; at least a part of the front-stage circuit elements and at least a part of the back-stage circuit elements are arranged in staggered layers on the first surface;

[0062] Specifically, in the rear-stage component area of ​​the first surface, the outermost printed circuit board laminate is hollowed out to expose the second outermost printed circuit board laminate; at least a portion of the front-stage circuit components are arranged on the outermost printed circuit board laminate, and at least a portion of the rear-stage circuit components are arranged on the second outermost printed circuit board laminate;

[0063] Alternatively, in the front-stage component area of ​​the first surface, the outermost printed circuit board stack is hollowed out to expose the second-outer printed circuit board stack; at least a portion of the rear-stage circuit components are arranged on the outermost printed circuit board stack, and at least a portion of the front-stage circuit components are arranged on the second-outer printed circuit board stack.

[0064] Preferably, the subsequent circuit element comprises a subsequent magnetic core, and the subsequent magnetic core is arranged in the middle hollow area.

[0065] Another aspect of the present invention provides a highly integrated composite electronic component group, comprising at least two flat component groups, wherein the at least two flat component groups are fixedly connected by a bonding medium layer, wherein a bonding material piece is disposed in the bonding medium layer, and the flat component groups are electrically connected by the bonding material piece;

[0066] The flat component group includes at least one passive multi-electrode device, and the flat component group can also be at least one of a PCB substrate and a semiconductor chip.

[0067] Preferably, the passive multi-electrode device comprises capacitor elements and a plastic package body arranged in a horizontal array, the plastic package body covers the capacitor elements, and the electrodes of the capacitor elements are exposed on the surface of the plastic package body.

[0068] Preferably, the passive multi-electrode device includes a capacitor element, a magnetic element and a plastic package arranged in a horizontal array, the capacitor element is arranged on the upper surface and / or lower surface of the magnetic element, the plastic package covers the capacitor element, and the electrodes of the capacitor element and the magnetic element are respectively exposed on the surface of the passive multi-electrode device.

[0069] Preferably, the passive multi-electrode device is a flat passive multi-electrode device, and the flat passive multi-electrode device is a layered capacitor, a flat magnetic element, or a stacked combination of a layered capacitor and a flat magnetic element.

[0070] Another aspect of the present invention provides a power module, including a transformer unit, a substrate and a circuit unit, wherein the transformer unit and the circuit unit are respectively arranged on two opposite sides of the substrate; the circuit unit is electrically connected to the winding of the transformer through the substrate.

[0071] The beneficial effects of the present invention are:

[0072] (1) The bonding medium layer of the present invention does not need to play a supporting role, so its thickness can be much smaller than the thickness of the first laminate in the laminate lamination method, that is, much smaller than 0.2 mm, thereby saving space. On the other hand, the laminate above the hollow area can be made according to conventional processes, thereby simplifying the process;

[0073] (2) The present invention forms a vertical section of the winding by using the side wall metal parts and the outer metal parts, which can save space and reduce impedance, and is conducive to the passage of large current;

[0074] (3) By using the carrier board of the present invention, the power module can embed the magnetic structure, which greatly reduces the size of the power module and reduces the height of the power module, which is beneficial to heat dissipation and improves the flexibility of wiring;

[0075] (4) Since the bonding method of the present invention does not have insufficient support, it can avoid the problems of poor filling and low density caused by traditional stacking, thereby improving the reliability of the carrier. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0077] Figure 1A to Figure 1B It is a schematic diagram of the prior art;

[0078] Figure 2 , FIG. 3A to FIG. 3H , FIG. 4A to FIG. 4E , Figure 5 is a schematic diagram of embodiment 1;

[0079] Figures 6 to 7E It is a schematic diagram of Embodiment 2;

[0080] Figures 8 to 9 It is a schematic diagram of embodiment 3;

[0081] FIG. 10A to FIG. 10X It is a schematic diagram of Embodiment 4;

[0082] FIG. 11A to FIG. 11J It is a schematic diagram of Embodiment 5;

[0083] FIG. 12A to FIG. 12B It is a schematic diagram of Embodiment 6;

[0084] FIG. 13A to FIG. 13B It is a schematic diagram of Embodiment 7;

[0085] Fig.14 is a schematic diagram of Embodiment 8;

[0086] FIG. 15A to FIG. 15D is a schematic diagram of Embodiment 9;

[0087] FIG. 16A to FIG. 16D is a schematic diagram of Embodiment 10;

[0088] 17A to 17D is a schematic diagram of Embodiment 11;

[0089] Figures 18 to 20 is a schematic diagram of Embodiment 12;

[0090] FIG. 21A to FIG. 22D is a schematic diagram of Embodiment 13;

[0091] FIG. 23A to FIG. 24C is a schematic diagram of Embodiment 14;

[0092] in:

[0093] 1 magnetic core; 2 carrier board; 3 hollow area; 4 printed circuit board stack; 41 first stack; 42 second stack; 43 third stack; 5 power circuit components; 6 bonding dielectric layer; 7 bonding material parts; 8 through-hole metal parts; 9 blind hole metal parts; 10 step area; 11 pins; 12 side wall metal parts; 13 anti-etching layer; 14 strippable layer; 15 interference source; 16 sampling circuit; 17 metal barrier layer; 18 anti-chemical plating layer; 19 outer metal parts; 20 insulating layer; 21 plastic package; 22 circuit components; 23 solid line area; 24 solder; 25 conductive adapter. DETAILED DESCRIPTION

[0094] The core of the present invention is to provide a highly integrated carrier board and power module. The carrier board can bury the magnetic structure, and the thickness of the bonding medium layer can be much smaller than the thickness of the stacking layer. The vertical section of the winding can be formed by the side wall metal parts and the outer metal parts. While greatly reducing the height of the power module and facilitating heat dissipation, the flexibility of wiring is improved.

[0095] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0096] Embodiment 1

[0097] like Figure 2As shown, the highly integrated carrier 2 disclosed in this embodiment includes two printed circuit board stacks 4, namely a first stack 41 and a second stack 42, the second stack 42 is provided with a hollow area 3, and the hollow area 3 is provided with a power circuit component 5; the first stack 41 and the second stack 42 are fixedly connected by an insulating adhesive medium layer 6, and the first stack 41 and the second stack 42 are electrically connected by a bonding material piece 7. The material of the bonding medium layer 6 includes insulating medium materials such as prepreg or ABF (Ajinomoto Build-up Film), and the material of the bonding material 7 includes solder, tin-silver alloy, tin-copper alloy, tin-silver-copper alloy, tin-antimony alloy, gold-tin alloy, high-lead solder, silver sintering paste, copper sintering paste, instantaneous liquid phase sintering material or conductive paste. The bonding material will not remelt within 220 degrees Celsius, so that the bonding material 7 will not remelt during application; the specific material can be selected by the technicians in this field according to the actual melting point requirements, for example, the melting point of tin-silver alloy, tin-copper alloy, tin-silver-copper alloy is about 220 degrees Celsius, the melting point of tin-antimony alloy is about 240 degrees Celsius, and the melting point of high-lead solder and gold-tin alloy is about 290 degrees Celsius. On the other hand, due to the effective restraint and protection of the insulating medium on the bonding material 7, the reliability of the bonding material can be effectively improved. The power circuit assembly 5 of this embodiment is the magnetic core 1 of the front-stage transformer. The windings of the front-stage transformer are respectively arranged on the surface of the magnetic core 1 and in the first laminate 41 and the second laminate 42. The windings on the surface of the magnetic core 1 are electrically connected to the bottom of the hollow area 3 through the bonding material 7. Preferably, the magnetic core 1 can also be fixedly connected to the bottom of the hollow area 3 by means of patch adhesive or the like. Since the bonding medium layer 6 in this embodiment does not need to play a supporting role, its thickness can be much smaller than the thickness of the first laminate in the laminate lamination method, that is, much smaller than 0.2 mm, so space can be saved. On the other hand, the laminate above the hollow area 3 can be made according to conventional processes, so the process can be simplified.

[0098] The size of the hollow area 3 can be set according to the size of the power circuit component 5 therein. In some embodiments, the hollow area 3 can also be expanded to at least one side edge of the second stack 42 according to actual needs.

[0099] In some other embodiments, the power circuit component 5 may also include various types of active / passive components such as an inductor component, a capacitor component, a controller, and a switch component of a Buck step-down circuit.

[0100] In a preferred embodiment, an insulating filling body is disposed in the hollow area 3 , and the insulating filling body covers the power circuit component 5 .

[0101] In a preferred embodiment, when one end of the bonding material 7 is connected to the through hole, the through hole needs to be plugged with resin and then copper plated on the surface to increase the bonding area, reduce the connection impedance and improve the connection reliability. Furthermore, metal slurry can be used to plug the hole to further improve heat dissipation and enhance conductivity.

[0102] FIG. 3A to FIG. 3E Shows Figure 2 A method for manufacturing the carrier board 2 shown (first process):

[0103] S1: Prepare the first stack 41, such as Figure 3A As shown;

[0104] S2: The bonding medium layer 6 is provided on the surface of the first laminate 41 and semi-cured. Figure 3B As shown;

[0105] S3: Opening a window on the bonding medium layer 6, such as Figure 3C As shown;

[0106] S4: Setting the bonding material piece 7 at the window opening position and baking to remove the solvent, such as Figure 3D As shown; the bonding material piece 7 can be a silver sintered material, a copper sintered material, a transient liquid phase sintered material or a conductive paste, etc.;

[0107] S5: The prefabricated second laminate 42 (such as Figure 3E As shown) is pressed together with the semi-finished product obtained in S4.

[0108] FIG. 3F to FIG. 3H Shows Figure 2 Another method for manufacturing the carrier board 2 shown (second process):

[0109] S1: preparing the first stack 41;

[0110] S2: Setting a bonding material 7, such as solder, on the surface of the first laminate 41. Figure 3F As shown, its shape can also be a hemispherical shape after reflow;

[0111] S3: The bonding medium layer 6 is provided on the surface of the first laminate 41 and semi-cured. Figure 3G As shown;

[0112] S4: Opening a window on the bonding medium layer 6, such as Figure 3H As shown, in some other embodiments, the window width may be slightly wider than the bonding material piece 7 to ensure that the surface of the bonding material piece 7 is fully exposed;

[0113] S5: The prefabricated second laminate 42 (such as Figure 3E As shown) is pressed together with the semi-finished product obtained in S4.

[0114] In some other embodiments, the bonding medium layer 6 and the bonding material piece 7 can also be generated on the second laminate 42, and the bonding medium layer 6 may not be provided in the hollow area. In some other embodiments, the bonding material piece 7 can be formed by further bonding two bonding material sub-pieces respectively provided on the first laminate 41 and the second laminate 42. In a preferred embodiment, the two bonding material sub-pieces can be the same material. In another preferred embodiment, the two bonding material sub-pieces are different materials, such as silver sintered material, copper sintered material, transient liquid phase sintered material or conductive paste on one side, and solder on the other side; or component A of transient liquid phase sintered material on one side, and component B of transient liquid phase sintered material on the other side.

[0115] like Figure 4A As shown, in a preferred embodiment, the carrier 2 includes a through-hole metal member 8 penetrating the first laminate 41 and the second laminate 42. The through-hole metal member 8 can be used to form an electrical connection between two prefabricated printed circuit board laminates.

[0116] like Figure 4B As shown, in a preferred embodiment, the second laminate 42 includes a second metal member penetrating therethrough, and the corresponding position of the first laminate includes a first metal member disposed in a blind hole (i.e., the dotted box in the figure); the second metal member, the first metal member, and the bonding material member 7 therebetween together form a longitudinal interconnection section. An outer layer may be further laminated on top of the first laminate 41 to form other electrical interconnection structures.

[0117] like Figure 4C As shown, in a preferred embodiment, the hollow area 3 in the carrier board 2 is provided with a step area 10 to increase wiring flexibility and make full use of the space to carry components 5 of different heights, such as the inductor of the Buck circuit is usually larger in height, and the input and output capacitors are usually smaller in height.

[0118] like Figure 4D As shown, in a preferred embodiment, a third stack 43 is further included. After the third stack 43 is interconnected with the first stack 41 through the bonding medium layer 6 and the bonding material 7, the first stack 41 is interconnected with the second stack 42. In this way, the flexibility of wiring can be further improved.

[0119] like Figure 4E As shown, in a preferred embodiment, no winding is arranged on the surface of the magnetic core 1, and the windings are arranged in a combination formed by the first laminate 41 and the second laminate 42. At this time, the magnetic core 1 does not need to be electrically interconnected with the surface of the hollow area 3.

[0120] like Figure 5As shown, in a preferred embodiment, two power circuit components 5 are arranged in the hollow area 3, which are respectively arranged on the surface of the first stack 41 and the bottom surface of the hollow area 3 of the second stack 42. The positions of the two power circuit components 5 in the vertical direction overlap. Preferably, the upper power circuit component 5 can be fixedly connected and electrically connected to the first stack 41 by patch glue and conductive connecting material 7, respectively. Adhesive glue can also be set in the gap between the two power circuit components 5 in the vertical direction to achieve thermal coupling. In some other embodiments, when the two power circuit components 5 are vertical devices, conductive materials can be set in the gap between them in the vertical direction to achieve electrical interconnection.

[0121] Embodiment 2

[0122] like Figure 6 As shown, the carrier board 2 of this embodiment includes a first laminate 41, a second laminate 42 and a third laminate 43. The first laminate 41 and the second laminate 42 are interconnected through a bonding medium layer 6 and a bonding material 7, and the second laminate 42 and the third laminate 43 are interconnected through a bonding medium layer 6 and a bonding material 7. The interlayer interconnection method is the same as that of the first embodiment. In this embodiment, the hollow area 3 runs through the second laminate 42, so that the power circuit component 5 can be set on the surface of the first laminate 41 and the third laminate 43, and the installation operation is easy to achieve on a plane.

[0123] In some other embodiments, the carrier board 2 may include N printed circuit board stack layers 4 and N-1 adhesive medium layers 6 .

[0124] like Fig. 7A As shown, in a preferred embodiment, two surfaces of the second laminate 42 are respectively provided with two hollow areas 3 which are not connected to each other, and the two hollow areas 3 can be respectively provided with corresponding power circuit components 5. The through-hole metal member 8 that runs through the entire carrier 2 and / or the through-hole metal member 8 that only runs through a single laminate can be provided according to actual needs.

[0125] In a preferred embodiment, if Figure 7B As shown, this embodiment and Fig. 7A The difference is that the hollowed-out areas 3 are respectively arranged in the first stack 41 and the third stack 43, the second stack 42 is not hollowed out, and only the power circuit components 5 are arranged at the corresponding positions of the hollowed-out areas.

[0126] In a preferred embodiment, if Figure 7C As shown, the surface of the second stack 42 is not provided with a power circuit component 5, but only serves as an intermediate interconnection.

[0127] In a preferred embodiment, if Fig.7DAs shown, two hollow areas 3 are respectively provided on the first stack 41 and the second stack 42 , and the two hollow areas 3 are connected to form a completed area, which can be used to accommodate a higher power circuit component 5 .

[0128] In a preferred embodiment, if Fig. 7E As shown, the power circuit component 5 is a magnetic core 1 (the magnetic core 1 can be composed of two magnetic core components arranged in parallel, and the magnetic core components can be in a U-shape or an E-shape, or the magnetic core 1 itself can also be set in a U-shape or an E-shape, etc.) that penetrates the second laminate 42 and is arranged in two hollow areas 3 on both sides of the second laminate 42. The second laminate 42 is mainly used to set the thick copper wiring winding. This part of the second laminate 42 can be reduced in thickness or trimmed in size in the horizontal direction by milling or other methods to improve space utilization. Preferably, an auxiliary winding parallel to the thick copper wiring winding (as the main winding) can also be arranged in the second laminate 42. The auxiliary winding is used to form a leakage inductance, and its width is set to be smaller than the main winding. The auxiliary winding can also be set as a thin copper layer in the second laminate 42 or on the surface of the second laminate 42.

[0129] Embodiment 3

[0130] like Figure 8 As shown, the difference between this embodiment and the first embodiment is that a power circuit component 5 in this embodiment is electrically interconnected with the surface of the first laminate 41 and the bottom of the hollow area 3 through pins 11. Preferably, the pins 11 can be leveled with the laminate surface by a brushing process. In some embodiments, the power circuit component 5 is an inductor, and the two ends of the winding are fanned out on the upper and lower surfaces respectively.

[0131] In a preferred embodiment, metallized semi-sunk holes are provided at positions corresponding to the pins 11 in the first stack 41 and the second stack 42 to increase the connection area and absorb the tolerance in the height direction.

[0132] like Fig. 9 As shown, in a preferred embodiment, at least a portion of the pins 11 are elastic pins, and the elastic pins are used to absorb height tolerance. Preferably, the power circuit components 5 in the hollow area 3 can be stacked, and the power circuit components 5 with lower height (such as chip capacitors, etc.) are arranged in the space below the power circuit components 5 corresponding to the pins 11 to further reduce the horizontal size of the unit.

[0133] Embodiment 4

[0134] like Fig. 10AAs shown, the difference between this embodiment and the first embodiment is that the hollow area 3 of this embodiment is provided with a side wall metal part 12 (for the convenience of illustration, the power circuit component 5 is not shown in the figure), and the side wall metal part 12 can be used for electrical connection, thermal connection or forming a signal shielding layer. In this embodiment, the side wall metal part 12 is electrically connected to the surface wiring metal of the hollow area 3 through a metallization process.

[0135] The principle of signal shielding layer is as follows Figures 10B to 10C As shown, Fig. 10B This is a common signal interference transmission path. There is a parasitic capacitor between the interference source 15 (such as a switching waveform) and the sampling circuit 16. The jump signal couples the interference current to the sampling circuit through the capacitor, thereby interfering with the sampling signal. Fig. 10A The hollow area 3 is usually used to place an inductor or a part of an inductor. The inductor, as an interference source 15, will interfere with external signals. Metallizing the sidewall of the hollow area 3 and connecting the metal to a relatively stable potential, such as power or ground wires such as VIN, GND, VOUT, and VDD, can cut off the interference coupling path. Fig. 10C As shown, the interference of the internal interference source 15 of the cavity to the external signal is eliminated. The side wall metal can also shield the high-frequency loop, reduce the loop inductance, and reduce the interference of the carrier board 2 system to the outside.

[0136] In some other embodiments, the sidewall metal piece 12 on the same sidewall of the hollow area 3 is divided into a plurality of sidewall metal pieces 12 with different electrical properties for connecting to different electrodes. Preferably, each sidewall metal piece 12 extends along the thickness direction of the carrier 2. The division method is not limited to etching, milling, drilling, etc.

[0137] FIG. 10D to FIG. 10I A method for manufacturing the second laminate 42 of the carrier board 2 of this embodiment is shown:

[0138] S1: Prepare a preform of the second laminate 42 to be hollowed out, such as Fig. 10D As shown;

[0139] S2: hollowing out the preform to form a hollow area 3, such as Fig.10E As shown, hollowing can be done by mechanical cutting and the like;

[0140] S3: metallizing the surface of the hollow area 3 to preliminarily form a side wall metal piece 12 connected to the bottom of the hollow area 3 and the outside of the hollow area 3, such as Fig.10F As shown;

[0141] S4: forming an anti-etching layer 13, such as Figure 10G As shown;

[0142] S5: Perform pattern definition, remove a portion of the anti-etching layer 13 according to a preset pattern, and expose the copper pattern to be etched, such as Fig. 10H As shown;

[0143] S6: Etching is performed and the anti-etching layer 13 is removed to obtain a second stack 42, such as Fig.10I shown.

[0144] In step S3, the surface metallization may be performed on the entire preform, or only on the bottom surface and side edges of the hollow area 3 under pattern protection;

[0145] In step S4 , the anti-etching layer 13 may be a metal anti-etching layer such as Sn, Ni, Au, etc., deposited by a metallization process.

[0146] In this embodiment, the specific method of graph definition in step S5 is:

[0147] S5.1: First, only Fig.10J The anti-etching layer 13 in the solid line area 23 is directly written by laser (i.e., the side wall and bottom surface of the hollow area 3, and the area adjacent to the side wall on the upper surface, the adjacent width is less than 1 mm);

[0148] S5.2: Use photosensitive resin to define the pattern on the front and back sides to define the anti-etching layer pattern.

[0149] The order of step S5.1 and step S5.2 can be interchanged, such as first defining the pattern of the anti-etching layer 13 on the upper and lower surfaces by protecting the photosensitive resin, then defining the pattern of the anti-etching layer 13 in the red dotted frame by laser direct writing, and then following the remaining steps. The depth of the hollow area 3 is greater than 1 / 2 of the focal length of the laser, preferably greater than one focal length, to avoid mutual interference between the surface and the exposed surface in the hollow area 3 during processing.

[0150] In step S5.1, the anti-etching layer 13 of the side wall can also be segmented by mechanical cutting. In this case, a micro-convex structure can be preset on the side wall of the anti-etching layer 13 and then removed by drilling / milling, such as Figure 10K As shown; or it can be directly removed by milling inside, such as Fig.10L shown. Figure 10K and Fig.10L It is a top view of the second stack 42 , showing only the anti-etching layer 13 at the height of the stack surface outside the hollow area 3 .

[0151] Figures 10M to 10O Another embodiment of steps S1 to S3 is shown, combining the through-hole metallization process and the surface metallization process:

[0152] S1-1: Preparation Figure 10MThe preform of the second laminate 42 to be hollowed out and provided with through holes is shown;

[0153] S2-1: Mechanical cutting to form hollow structures and through holes, such as Fig.10N As shown;

[0154] S3-1: Surface metallization to form through-hole metal parts 8 and sidewall metal parts 12, such as Fig.10O As shown;

[0155] The subsequent process is similar to the aforementioned manufacturing method and will not be described in detail here.

[0156] In a preferred embodiment, some through holes in the hollow area 3 may not be plugged to form natural exhaust channels.

[0157] Figure 10P to Figure 10R Another implementation of steps S1-1 to S2-1 is shown:

[0158] S1-2: Prepare as Figure 10P The preform shown in the figure has a metal barrier layer 17 disposed on the preform (for the portion that does not need to be hollowed out, the metal barrier layer 17 is disposed on the surface of the preform; for the area to be hollowed out, the metal barrier layer 17 is disposed inside the preform, and forms the bottom of the hollowed-out area 3 in a subsequent step);

[0159] S2-2: Grooving, such as by laser, plasma, etc., through the surface window, remove the residual dielectric layer, until the metal barrier layer 17 is exposed, such as Figure 10Q As shown; mechanical cutting forms a through hole, such as Figure 10R As shown; in some embodiments, the material at most depths may be removed mechanically first and then the metal barrier layer 17 may be exposed by laser ablation, plasma grinding, or the like.

[0160] The subsequent process is similar to the aforementioned manufacturing method and will not be described in detail here.

[0161] Figure 10S to Figure 10V Another implementation of steps S1-1 to S3-1 is shown:

[0162] S1-3: Prepare as Fig. 10S The preform shown in the figure has a metal barrier layer 17 disposed on the preform (for the portion that does not need to be hollowed out, the metal barrier layer 17 is disposed on the surface of the preform; for the area to be hollowed out, the metal barrier layer 17 is disposed inside the preform, and the bottom of the hollowed-out area 3 and the bottom of the blind hole of the hollowed-out area 3 are formed in subsequent steps);

[0163] S2-3: Grooving, and using the preset pattern at the bottom as a self-aligned pattern for laser and plasma removal of the medium, such as Figure 10TAt the same time, a blind hole is formed at the reserved blind hole position on the metal barrier layer 17 at the bottom of the hollow area 3; a through-hole is formed by mechanical cutting, such as Figure 10U As shown;

[0164] S3-3: Surface metallization to form through-hole metal parts 8, blind-hole metal parts 9 and sidewall metal parts 12, such as Figure 10V As shown;

[0165] The subsequent process is similar to the aforementioned manufacturing method and will not be described in detail here.

[0166] Figure 10W to Figure 10X Another implementation of step S1-1 to step S2-1 is shown:

[0167] S1-4: Prepare as Figure 10W The preform shown has a peelable layer 14 disposed inside the preform;

[0168] S2-4: Milling to the peelable layer 14, such as Figure 10X As shown; peel off the peelable layer 14, make a through hole, form Fig.10N Similar structures are used in subsequent production steps.

[0169] Embodiment 5

[0170] The difference between this embodiment and the fourth embodiment is that Fig.11A As shown, the side wall metal part 12 and the wiring layer at the bottom of the hollow area 3 are further electrically connected through a conductive material 24, such as solder, conductive paste, sintered material, etc., which can reduce the electrical connection impedance. Fig. 11B As shown, the upper end of the sidewall metal member 12 may not extend on the upper surface of the second stack 42, or may further extend laterally on the upper surface, and the sidewall metal member 12 may also be electrically connected to other electrical interconnection structures inside the second stack.

[0171] FIG. 11C to FIG. 11F The manufacturing method of this embodiment is shown:

[0172] S1: Prepare as Fig. 11C The three-part preform sub-component shown in the figure, part A is a laminated sub-component with a through-type hollowing and a hollow area 3 with a side wall metal coating, and part B is a laminated sub-component without a hollow area, and a hollow PP layer is laminated in the middle to obtain Fig.11D The complete preform shown;

[0173] S2: Drilling, surface metallization and pattern definition, the implementation of which is similar to the above-mentioned embodiment, and will not be repeated here, and finally forms the following Fig.11E The bottom of the side wall of the hollow area 3 shown is not yet electrically connected to the stacked layer;

[0174] S3: The side wall metal piece 12 is electrically connected to the bottom of the hollow area 3 through the conductive material 24, such as Fig.11F shown.

[0175] FIG. 11G to FIG. 11J Another method of making this embodiment is shown:

[0176] S1-1: Prepare Fig.11G The three-part preform sub-component shown in the figure, part A is a through-type hollow laminated sub-component (the side wall of the hollow area 3 is not metallized), and part B is a laminated sub-component with a chemical-resistant coating 18 provided at the corresponding position of the hollow area 3, and a hollow PP layer is laminated in the middle to obtain Fig.11H The complete preform shown;

[0177] S2-1: Drilling, surface metallization and pattern definition. During the surface metallization process, the side wall of the hollow area 3 is metallized at the same time. The implementation method is similar to the above-mentioned embodiment and will not be repeated here. Further, the resist coating 18 is opened, such as Fig.11I As shown;

[0178] S3-1: The side wall metal part 12 is electrically connected to the bottom of the hollow area 3 through solder, such as Fig.11J shown.

[0179] Embodiment 6

[0180] The difference between this embodiment and the fourth embodiment is that Fig. 12A As shown, the side wall of the hollow area 3 has a step area 10, the surface of the step area 10 is covered with a metal layer, and is electrically connected to the wiring layer at the bottom of the hollow area 3 through a metal jumper or the like.

[0181] In a preferred embodiment, if Fig. 12B As shown, a power circuit component 5 with a relatively low height is also arranged on the step region 10 , and a metallization layer for electrical connection may be provided at the side wall at the edge of the step region 10 , or there may be no metallization layer.

[0182] Embodiment 7

[0183] The difference between this embodiment and the fourth embodiment is that, in addition to the side wall metal piece provided in the hollow area 3, an outer metal piece 19 is also provided on the outer side wall of the carrier plate 2. Fig.13A As shown, the horizontal size can be further reduced and the flow capacity and heat dissipation capacity can be improved.

[0184] In a preferred embodiment, if Fig. 13BAs shown, a through-hole metal component 8 penetrating the entire carrier 2, the first stack 41 or the second stack 42 can be provided at a corresponding position of the outer metal component 19 of the second stack 42. The through-hole metal component 8 can be used to electrically connect with the outer metal component 19 to further reduce impedance.

[0185] Embodiment 8

[0186] This embodiment is embodiment 2 ( Fig. 7E ) and the combination of embodiment 4, such as Fig.14 As shown, a cross-laminated magnetic core 1 (the magnetic core 1 is formed by buckling magnetic core sub-components) is arranged in two adjacent hollow areas 3, and the middle second laminate 42 is used to set thick copper wiring to form a winding, and the winding surrounding the upper / lower half of the magnetic core 1 fans out to the upper and lower surfaces respectively in the upper / lower hollow areas 3 through the side wall metal parts 12 and the through-hole metal parts 8.

[0187] Embodiment 9

[0188] The difference between this embodiment and the first embodiment is that the magnetic core 1 is a ring-shaped magnetic core, and at the same time, the hollow area 3 accommodating the magnetic core 1 is a ring-shaped area. Fig.15A and Fig. 15B As shown ( Fig. 15B It is a top view of the cross section at the height of the hollow area 3. The area marked by the dotted line is the primary winding part that bypasses the upper and lower surfaces of the magnetic core 1). The winding surrounding the magnetic core 1 includes the primary winding (P1) and the first secondary winding (S1). The primary / secondary windings are at least one circle around the magnetic core 1. When used, the primary / secondary windings can be connected in series with their corresponding switching elements (the switching elements can be arranged on the surface of the carrier 2). The primary winding of this embodiment is arranged on the surface of the magnetic core 1, and the two ends of the primary winding are electrically connected to the first stack 41 or the second stack 42, and are led to the surface of the carrier 2 through the electrical interconnection structure inside the first stack 41 and / or the second stack 42. In a preferred embodiment, an insulating stress buffer layer can be arranged between the primary winding arranged on the outside of the magnetic core and the magnetic core, which can play the functions of stress buffering (preventing the increase of core loss), insulation enhancement and adhesion fixation.

[0189] In this embodiment, the secondary winding is formed by the electrical interconnection structure within the first stack 41 and the second stack 42 , wherein the horizontal section is the intra-layer electrical interconnection structure, and the vertical section is the through-hole metal part 8 and the bonding material part 7 .

[0190] In a preferred embodiment, the primary winding disposed on the surface of the magnetic core can realize series and parallel connection of some windings through the transition connection of the first laminate 41 or the second laminate 42. The secondary winding can also be connected in parallel through multi-layer wiring in the laminate to reduce impedance.

[0191] It should be noted that, for a transformer, the so-called primary / secondary winding is a relative concept and has no specially designated special attributes, so the names of the primary / secondary windings in this embodiment can be interchangeable.

[0192] In some other embodiments, the secondary winding may be arranged around 2 to 4 sides of the magnetic core (generally, the magnetic core is in the shape of a “U” with 4 sides). In some other embodiments, the magnetic core is in the shape of a ring.

[0193] In some other embodiments, when the primary winding has a large current, it is set on the surface of the magnetic core through metallization process, flat wire winding, etc. When the number of turns of the primary winding is greater than 10 turns or even 30 turns, it can also be directly wound with round wire.

[0194] In some other embodiments, the outer periphery of the magnetic core is surrounded by an opening on the side wall of the carrier for exhaust to ensure the reliability of the carrier temperature cycle.

[0195] In some other embodiments, the periphery of the magnetic core is surrounded by a carrier board. In this case, exhaust holes can be provided on the surface of the carrier board to ensure reliability of temperature cycling of the carrier board.

[0196] In addition, when the lead-out end of the primary winding is fanned out through the interlayer interconnection, there will be a partial interference area with the secondary winding, and those skilled in the art can avoid this through a reasonable layout on the plane area.

[0197] In a preferred embodiment, if Fig. 15C and Fig.15D As shown ( Fig.15D 3 is a top view of the cross section at the height of the hollow area 3), the portion of the first secondary winding located in the middle of the annular area does not share a vertical segment.

[0198] Embodiment 10

[0199] The difference between this embodiment and the ninth embodiment is that Fig.16A As shown, this embodiment further includes a second secondary winding, which is arranged outside the first secondary winding. Since the first secondary winding surrounds the inner side of the second secondary winding, the first secondary winding does not share a vertical segment in the middle of the annular area, and the second secondary winding may share a vertical segment in the middle of the annular area, or may not share a vertical segment.

[0200] Similarly, more primary / secondary windings may be arranged outside the second secondary winding, or more primary / secondary windings may be arranged between the first secondary winding and the second secondary winding, and those skilled in the art may arrange them according to actual needs. The winding arranged on the outermost layer may directly use the surface of the carrier 2 to form a transverse section of the winding, while other windings (including the primary / secondary windings) may lead the terminals to the surface of the carrier 2 through the electrical interconnection structure.

[0201] In a preferred embodiment, if Fig. 16B As shown, at least one pair of terminals of the primary / secondary winding integrated with the magnetic core 1 , one of which is led out to the upper surface of the carrier 2 through the first laminate 41 , and the other is led out to the lower surface of the carrier 2 through the second laminate 42 .

[0202] In a preferred embodiment, if Fig. 16C As shown, an insulating layer 20 is disposed on the surface of the magnetic core 1 , and the insulating layer 20 also covers the winding disposed on the surface of the magnetic core 1 .

[0203] In a preferred embodiment, when the primary / secondary windings have high voltage insulation requirements, the entire hollow area 3 can be used as the high voltage side, such as Fig.16D As shown, the hollow area 3 can also be filled with glue, and the glue is mainly used to cover the magnetic core 1 (and other high-voltage side components arranged in the hollow area 3) and the corresponding electrical connection points.

[0204] Embodiment 11

[0205] The difference between this embodiment and the tenth embodiment is that the primary winding and the first secondary winding of this embodiment are respectively formed by the side wall metal part 12 and the outer metal part 19 to form at least a part of the vertical section. Fig.17A As shown, only the vertical section of the second secondary winding in the middle of the annular area is a common through-hole metal part 8, and the remaining vertical sections of the secondary winding are side wall metal parts 12 or outer metal parts 19. The advantage of this arrangement is that it can further improve the space utilization of the carrier 2 and reduce impedance.

[0206] In a preferred embodiment, if Fig. 17B As shown, the through-hole metal piece 8 shared by the middle vertical section is a via, which can further improve the space utilization of the carrier board 2 and reduce the impedance. In another preferred embodiment, one or more wiring layers can be stacked on the surface to integrate the control and drive wiring, and the power connection points of the primary and secondary windings are matched with the packaging of the connected switch elements. By staggered arrangement, the wiring restrictions caused by the packaging of the switch device can be effectively avoided, and the connection impedance of the power loop can be reduced.

[0207] In some other embodiments, such as Fig. 17C As shown, only the side wall metal part 12 may be provided, and the vertical sections of the second secondary winding are all formed by the through-hole metal part 8 .

[0208] In a preferred embodiment, if Fig.17DAs shown, a blind hole metal part 9 is provided at a corresponding position adjacent to the side wall metal part 12 / outer metal part 19 in the first stack 41 / second stack 42, and the blind hole metal part 9 is connected in parallel with the corresponding side wall metal part 12 / outer metal part 19 to further improve space utilization and reduce parasitic impedance. Those skilled in the art can flexibly set the position of the parallel structure according to actual conditions.

[0209] Embodiment 12

[0210] The difference between this embodiment and the tenth embodiment is that Fig.18 As shown, the power circuit assembly 5 disposed in the hollow area 3 may include, in addition to the magnetic core 1, resistors and capacitors, drive components, controllers, etc., and may also include switch components connected in series with the windings. Other components of the power circuit assembly 5 may be stacked with the magnetic core 1.

[0211] In a preferred embodiment, components with relatively large heat generation, such as switch components connected in series with windings, can be thermally connected to the outside through thermal vias and can also have electrical and thermal connection functions. Preferably, in addition to thermal vias, metallized strip copper or even local heat sinks (embedded copper blocks) can be used to achieve electrical and thermal connections to the outside.

[0212] In a preferred embodiment, if Fig.19 As shown, in order to further reduce the impedance, the switch elements connected in series with the windings are usually connected in parallel. In this case, one switch element (represented by the power circuit component 5 in the figure) can be set in the hollow area 3, and the other switch can be set at the corresponding position on the surface of the carrier 2 to form a pair. Preferably, the thickness of the stacked layer with switch elements set in pairs should be reduced as much as possible to minimize the conduction thermal resistance to the heat dissipation surface (for example, a double-sided PCB that does not include an internal horizontal wiring layer). Preferably, the switch element set on the surface of the carrier 2 can use a double-sided heat dissipation device (metal exposed on the back).

[0213] In a preferred embodiment, if Fig. 20 As shown, the surface of the magnetic core 1 is not electrically interconnected with the laminate, and the primary / secondary windings are both realized through the electrical interconnection structure within and between the laminates. Preferably, the magnetic core 1 can be fixed in the hollow area 3 by an adhesive material.

[0214] Embodiment 13

[0215] In this embodiment, the surface of the carrier board 2 of the above-mentioned embodiment is further equipped with other circuit elements 22 to form a power module. The circuit elements 22 include various active / passive elements, such as capacitor elements, drive elements, controllers, switch elements, etc. The circuit elements can be directly arranged on the surface of the carrier board 2, such as Fig.21A and Fig. 21BPreferably, the surface of the carrier board 2 can be plastic-sealed to form a plastic-sealed body 21 (in some other embodiments, the plastic-sealed body 21 can also be a plastic-sealed protective body formed by plastic-filling), which is used to protect circuit components and improve the withstand voltage performance, such as Fig. 21C shown.

[0216] In a preferred embodiment, the surface of the carrier 2 can be mounted with another substrate, and the circuit element 22 can be mounted on the surface of the substrate, such as Fig.22A As shown, the circuit element 22 is connected in series with the winding of the transformer through the substrate to form a loop. In a preferred embodiment, the surface of the substrate and the circuit element 22 can also be plastic-sealed to form a plastic-sealed body 21 for protecting the circuit element, such as Fig. 22B shown.

[0217] In a preferred embodiment, if Fig. 22C and Fig.22D As shown ( Fig.22D (a top view), the carrier 2 is used for power conversion between the high-voltage side and the low-voltage side, the plastic package 21 is arranged on the surface of the carrier 2 corresponding to the high-voltage side, and a conductive adapter 25 can be arranged in the plastic package 21, such as a copper column, a stud, a nut, a metalized via or a solder ball, which passes through the plastic package 21 and fans out to the surface of the plastic package 21. And the external electrical connection is achieved through an insulated conductor, preferably, the connection point exposed on the surface of the insulating medium can be near the axis of the module, so that the creepage distance can be increased.

[0218] Embodiment 14

[0219] The power module of this embodiment is a two-stage step-down module. Fig.23A As shown, the carrier board 2 used in the two-stage step-down module can be divided into a front-stage component area and a rear-stage component area. In the horizontal layout, the front-stage component area is arranged at the periphery of the carrier board 2, and the rear-stage component area is arranged in the middle of the carrier board 2, which can effectively simplify the interconnection. The front / rear stage component areas respectively include their own hollow areas and corresponding front / rear stage power circuit components. In this embodiment, Fig.23A The left hollow area 3 and the right hollow area 3 are a hollow area 3 connected in an annular manner, wherein the magnetic core 1 is an annular magnetic core, and its structure can refer to the aforementioned embodiment, and will not be described here in detail. In a preferred embodiment, the area of ​​the front-stage component area is smaller than the rear-stage component area, that is, the front-stage area is a narrower ring, surrounding the rear-stage area with a larger area, so as to provide a larger space for the rear-stage component area with a larger current; at this time, the annular magnetic core in the front-stage area is also a thin ring with narrow bars and a larger opening in the middle.

[0220] In a preferred embodiment, if Fig. 23BAs shown, the front / rear component area can have different stacking structures, for example, the first stacking layer 41 on the upper surface of the surface carrier is only arranged in the front component area, or only arranged in the rear component area, so that the front / rear circuit components are arranged in staggered layers to meet the height requirements of different components or increase the creepage distance, etc. Those skilled in the art can flexibly set the bonding material 7 and the bonding medium layer 6, the height and range of the hollow area 3, and the number and arrangement of independent front / rear component areas can also be flexibly set to meet the requirements of different wiring complexities and adapt to the restrictions of inconsistent heights at different positions of the system. Preferably, two or more carriers of the above-mentioned embodiments can also be stacked to improve wiring flexibility.

[0221] In a preferred embodiment, the power module includes at least two electronic units, which are single electronic components or integrated bodies of multiple electronic components or substrates containing multiple layers of electrical circuit layers. At least one of the electronic units contains at least one semiconductor device, capacitor device or magnetic device, which is referred to as the first electronic unit, which is equivalent to the electronic component 5 in the above-mentioned structures; the corresponding other is the second electronic unit. Each of the at least two electronic units has at least one surface with multiple exposed electrodes that are flat against each other, and the electrodes of the two electronic units correspond to each other. A bonding medium layer with corresponding electrode windows is placed on the surface containing the electrode of one of the electronic units, and then a sintering slurry is set at the window, and then it is pressed together with the other electronic unit, and the structure is fixed while realizing internal high-quality high-temperature resistant electrical interconnection, forming the high-temperature resistant electronic module or the pre-finished product of the electronic module production process.

[0222] In some embodiments, the first electronic unit is an integrated body in which multiple electronic components are integrated together through a plastic packaging process. Fig.24A The plastic-encapsulated integrated body is a passive multi-electrode device formed by vertically stacking a plurality of small-sized electronic components in a horizontal array and at least one large component (such as a magnetic component) and then plastic-encapsulating the components; Fig. 24B The plastic packaged integrated body is a passive multi-electrode device formed by plastic packaging of multiple electronic components in a horizontal array. To ensure flatness, Fig.24A and Fig. 24B The multiple electronic components in the horizontal array are first leveled by a carrier and then plastic-sealed. After plastic sealing, the electrodes are exposed and cleaned. If necessary, the surface of the plastic-sealed body is electroplated again so that the surface electrodes of the first electronic unit of the plastic sealing have more effective sintering and interconnection conditions. Fig.24C The first electronic unit is a flat passive multi-electrode device, such as a layered capacitor, a flat magnetic element, or a stacked combination of the two.

[0223] The power supply module is a common circuit such as Buck step-down circuit and boost step-up circuit, which needs to stack and integrate power semiconductor components, power semiconductor circuit suppression capacitors (Buck input capacitor, Boost output capacitor), magnetic components and even filter capacitors (Buck output capacitor, Boost input capacitor) matched with the magnetic components and module pins to achieve a structural solution with the smallest footprint. During the manufacturing process of this structure, multiple capacitors are fixed by plastic sealing with magnetic components as structural carriers. After the electrodes are led out, they are interconnected with the PCB substrate using sintering slurry and window bonding dielectric layer.

[0224] In some more complex high-density and high-reliability power supplies, multiple components are usually integrated together using a full plastic encapsulation process. However, in traditional processes, the electrical connection of each component is carried out through tin soldering. When the user solders and uses it, the solder inside the module will remelt, resulting in structural instability or even solder short circuit failure. First, these electronic components are plastic encapsulated and the electrodes are led to the surface, and then sintered slurry and window bonding dielectric layers are used to interconnect with the PCB substrate.

[0225] therefore, Fig.24A The second electronic unit in / B is a PCB substrate, and power semiconductors can be placed inside or on the other side of the substrate to achieve high density, low internal resistance, low internal thermal resistance and complex electrical functions.

[0226] like Fig.24C The embodiment shown is used for ultra-thin scenarios such as those with a height of less than 1 mm. The first electronic unit is a flat passive multi-electrode device, and the second electronic unit is a semiconductor chip. The upper surface of the semiconductor chip has multiple electrodes, which are electrically and structurally interconnected with the multi-electrode passive device through a windowed adhesive dielectric layer, and the electrodes of the first electronic unit are led to the lower surface of the second electronic unit.

[0227] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0228] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A highly integrated carrier board, characterized in that: The invention comprises at least two prefabricated printed circuit board stacks, at least one of which has a first surface, the first surface is provided with at least one hollow area, the hollow area is buried in the carrier, the printed circuit board stacks are fixedly connected by an insulating bonding medium layer, the carrier is provided with an electrical connector penetrating the bonding medium layer, and the hollow area is provided with at least one power circuit component.

2. The carrier board according to claim 1, characterized in that: The power circuit assembly includes at least one magnetic core, and the printed circuit board stack includes at least a portion of a winding, wherein the winding and the magnetic core are used to form a magnetic element in the power circuit by cooperating with each other.

3. The carrier board according to claim 2, characterized in that: At least one of the hollow areas is provided with a side wall metal piece, and at least one of the side wall metal pieces is used to form at least a part of the winding, and the winding and the magnetic core are used to form a magnetic element in the power circuit by cooperating with each other.

4. The carrier board according to claim 2, characterized in that: The outer edge side wall of the printed circuit board stack where the side wall metal piece is located is provided with an outer metal piece, and the outer metal piece is used to form at least a part of the winding.

5. The carrier board according to claim 1, characterized in that: The electrical connector penetrating the bonding medium layer comprises a bonding material piece, and the bonding material piece is made of a non-remelting conductive bonding material; the non-remelting conductive bonding material will not remelt within 220 degrees Celsius.

6. The carrier board according to claim 1, characterized in that: The power circuit assembly and the printed circuit board stack are electrically connected via one or more conductive connectors, and the conductive connectors are made of a non-remelting conductive bonding material; the non-remelting conductive bonding material will not remelt within 220 degrees Celsius.

7. The carrier board according to claim 5 or 6, characterized in that: The non-remelting conductive bonding material includes at least one of solder, tin-silver alloy, tin-copper alloy, tin-silver-copper alloy, tin-antimony alloy, gold-tin alloy, high-lead solder, silver sintering paste, copper sintering paste, transient liquid phase sintering material or conductive paste.

8. The carrier board according to claim 1, characterized in that: The electrical connector penetrating the bonding medium layer includes a via-plating component.

9. The carrier board according to claim 1, characterized in that: The material of the bonding medium layer includes at least one of prepreg or ABF.

10. The carrier board according to claim 1, characterized in that: An insulating filling body is arranged in the hollow area, and the insulating filling body covers the power circuit component.

11. The carrier board according to claim 1, characterized in that: The hollow structure includes at least one step area, and power circuit components of different heights are respectively arranged inside and outside the step area.

12. The carrier board according to claim 1, characterized in that: At least one of the printed circuit board stacks has a second surface, the second surface has no hollow area, a power circuit component is arranged on the second surface, and the power circuit component on the second surface is located in the hollow area opened in another printed circuit board stack.

13. The carrier board according to claim 1, characterized in that: At least two adjacent printed circuit board stacks are provided with hollow areas, and the corresponding hollow areas are connected.

14. The carrier board according to claim 1, characterized in that: At least three printed circuit board stacks are provided; at least one of the printed circuit board stacks is penetrated by a hollow area.

15. The carrier board according to claim 1, characterized in that: At least three printed circuit board stacks are provided; at least two hollow areas are provided; the hollow areas are respectively opened in different printed circuit board stacks and / or opened on different surfaces of the printed circuit board stacks.

16. The carrier board according to claim 1, characterized in that: The magnetic core is arranged across at least one printed circuit board stack, and a plurality of hollow areas are provided, and the plurality of hollow areas are respectively used to accommodate a part of the magnetic core.

17. The carrier board according to claim 1, characterized in that: At least one power circuit component is electrically connected to two different printed circuit board stacks via pins.

18. The carrier board according to claim 17, characterized in that: An electrical connection semi-sunk hole is arranged on the printed circuit board stack corresponding to at least one of the pins.

19. The carrier board according to claim 17, characterized in that: At least one of the pins is a flexible pin.

20. The carrier board according to claim 1, characterized in that: At least one of the hollowed-out areas is provided with a sidewall metal piece, and at least one of the sidewall metal pieces is used to form a signal shielding layer.

21. The carrier board according to claim 3 or 20, characterized in that: A plurality of the side wall metal pieces are arranged on a side wall of the same hollow area. The side wall metal pieces extend along the thickness direction of the carrier plate and are arranged in an array along the horizontal direction.

22. The carrier board according to claim 3 or 20, characterized in that: The side wall metal piece is provided with solder at the top or bottom of the hollow area, or the side wall metal piece and the printed circuit board laminate are electrically connected via flying leads.

23. A highly integrated transformer unit, characterized in that: It comprises an annular magnetic core, a primary winding, a secondary winding and a carrier, wherein the carrier comprises at least two prefabricated printed circuit board stacks; at least one of the printed circuit board stacks is provided with an annular hollow area for accommodating the annular magnetic core, the printed circuit board stacks are fastened to cover the annular magnetic core, and the printed circuit board stacks are fixedly connected by an adhesive medium layer; at least a part of the primary winding and the secondary winding is arranged in the printed circuit board stack.

24. The transformer unit according to claim 23, characterized in that One of the primary winding or the secondary winding is arranged on the surface of the annular magnetic core and is electrically connected to the printed circuit board stack through at least two conductive connectors.

25. The transformer unit according to claim 24, characterized in that An insulating transition layer is also arranged between one of the primary winding or the secondary winding and the surface of the annular magnetic core.

26. The transformer unit according to claim 24, characterized in that An insulating protection layer is also provided on the outer side of one of the primary winding or the secondary winding.

27. The transformer unit according to claim 24, characterized in that The other of the primary winding or the secondary winding is arranged on a printed circuit board stack and includes a first winding and a second winding which are nested inside and outside.

28. The transformer unit according to claim 27, characterized in that A plurality of side wall metal pieces are arranged in the annular hollow area. The side wall metal pieces extend along the thickness direction of the carrier plate and are arranged in an array along the horizontal direction. The side wall metal pieces are used to form the vertical portion of the first winding.

29. The transformer unit according to claim 27, characterized in that The outer edge sidewalls of the printed circuit board stack are provided with a plurality of outer metal parts, and the outer metal parts are used to form the vertical part of the second winding.

30. The transformer unit according to claim 24, characterized in that The at least two conductive connecting members are electrically connected to different printed circuit board stacks respectively.

31. The transformer unit according to claim 23, characterized in that The primary winding and / or the secondary winding includes at least three windings nested inside and outside.

32. The transformer unit according to claim 23, characterized in that The carrier board is provided with vertical via holes, the bonding medium layer is provided with bonding material pieces at positions corresponding to the vertical via holes, and the vertical via holes and the bonding material pieces are used to form vertical sections of the primary winding and / or vertical sections of the secondary winding.

33. The transformer unit according to claim 23, characterized in that The carrier board is provided with a vertical via hole, the vertical via hole penetrates the bonding medium layer, and the vertical via hole is used to form a vertical section of the primary winding and / or a vertical section of the secondary winding.

34. The transformer unit according to claim 33 or 33, characterized in that: At least one vertical through hole arranged in the middle of the annular magnetic core is a vertical segment shared by multiple primary windings or a vertical segment shared by multiple secondary windings.

35. The transformer unit according to claim 23, characterized in that It also includes circuit elements, which include switching elements and / or driving elements and / or capacitor elements and / or controllers; the switching elements include primary switching elements and / or secondary switching elements, the primary switching elements are connected in series with the primary winding, and the secondary switching elements are connected in series with the secondary winding.

36. The transformer unit according to claim 35, characterized in that The carrier board has a heat dissipation surface; the circuit element is arranged on the heat dissipation surface, and / or the circuit element is arranged in the hollow area and on a surface close to the heat dissipation surface.

37. The transformer unit according to claim 35, characterized in that The switch elements are arranged in pairs in parallel on two opposite sides of the printed circuit board stack and in corresponding positions. One of the switch elements arranged in pairs in parallel is located in the hollow area, and the other is located on the outer surface of the carrier board.

38. The transformer unit according to claim 35, characterized in that It also includes a plastic package, the circuit element is arranged on the outer surface of the carrier, and the plastic package covers the circuit element and the outer surface.

39. The transformer unit according to claim 38, characterized in that A conductive adapter is arranged in the plastic package body, one end of which is electrically connected to the carrier board and the other end is exposed on the surface of the plastic package body; the conductive adapter is arranged at a position adjacent to the central axis of the transformer unit.

40. A highly integrated two-stage power supply device, characterized in that: The invention comprises a two-stage structure carrier, a front-stage magnetic core, a front-stage winding, a front-stage circuit element and a rear-stage circuit element, wherein the two-stage structure carrier comprises at least two printed circuit board stacks, and the two-stage structure carrier is divided into a front-stage element area and a rear-stage element area according to circuit functions, and the front-stage element area is an annular area surrounding the rear-stage element area; At least one of the printed circuit board stacks has an annular hollow area in the front-stage component area, the front-stage magnetic core is annular, and the front-stage magnetic core is arranged in the annular hollow area; The front-stage winding is arranged in the front-stage element area, and at least a part of the front-stage winding is arranged in the printed circuit board stack; At least one of the printed circuit board stacks has a middle hollow area in the rear-stage component area, and at least a portion of the rear-stage circuit components are arranged in the middle hollow area; The printed circuit board stack is fixedly connected via a bonding medium layer, and the two-stage structure carrier is provided with an electrical connector penetrating the bonding medium layer.

41. The power supply device according to claim 40, characterized in that: The area of ​​the front-stage component region is smaller than that of the rear-stage component region.

42. The power supply device according to claim 40, characterized in that: At least a portion of the front-stage circuit elements are disposed on an outer surface of the two-stage structure carrier, and / or at least a portion of the rear-stage circuit elements are disposed on an outer surface of the two-stage structure carrier.

43. The power supply device according to claim 40, characterized in that: The two-stage structure carrier has a first surface; in the front-stage component area or the back-stage component area of ​​the first surface, the outermost printed circuit board stack is hollowed out to expose the second outer printed circuit board stack; at least a portion of the front-stage circuit elements and at least a portion of the back-stage circuit elements are staggered on the first surface.

44. The power supply device according to claim 40, characterized in that: The latter circuit element comprises a latter magnetic core, and the latter magnetic core is arranged in the middle hollow area.

45. A highly integrated composite electronic component group, characterized in that: It comprises at least two flat element groups, wherein the at least two flat element groups are fixedly connected by a bonding medium layer, a bonding material piece is arranged in the bonding medium layer, and the flat element groups are electrically connected by the bonding material piece; The flat component group includes at least one passive multi-electrode device, and the flat component group can also be at least one of a PCB substrate and a semiconductor chip.

46. ​​The composite electronic component assembly according to claim 45, characterized in that: The passive multi-electrode device comprises capacitor elements and a plastic package body arranged in a horizontal array. The plastic package body covers the capacitor elements, and electrodes of the capacitor elements are exposed on the surface of the plastic package body.

47. The composite electronic component assembly according to claim 45, characterized in that: The passive multi-electrode device includes a capacitor element, a magnetic element and a plastic package arranged in a horizontal array, the capacitor element is arranged on the upper surface and / or lower surface of the magnetic element, the plastic package covers the capacitor element, and the electrodes of the capacitor element and the magnetic element are respectively exposed on the surface of the passive multi-electrode device.

48. The composite electronic component assembly according to claim 45, characterized in that: The passive multi-electrode device shown is a flat passive multi-electrode device, and the flat passive multi-electrode device is a layered capacitor, a flat magnetic element, or a stacked combination of a layered capacitor and a flat magnetic element.

49. A power module, characterized in that: It includes the transformer unit as described in claim 23, and also includes a substrate and a circuit unit, wherein the transformer unit and the circuit unit are respectively arranged on two opposite sides of the substrate; the circuit unit is electrically connected to the winding of the transformer through the substrate.

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