WO2018040638A1 - Intelligent power module and manufacturing method therefor - Google Patents

Abstract

Disclosed is an intelligent power module (100) and a manufacturing method therefor. The intelligent power module (100) comprises: circuit wiring (1), a plurality of circuit elements (2) and seal resin (3), wherein at least one end part of the circuit wiring (1) is provided with a solder pad (11) used for being electrically connected to an external circuit; the plurality of circuit elements (2) are arranged on an upper surface of the circuit wiring (1), a part of the plurality of circuit elements (2) are power elements (21), and the other part are driving elements (22) corresponding to the power elements (21), at least one driving element (22) is arranged on the power element (21) corresponding thereto, and the power element (21) and the driving element (22) are electrically connected to the circuit wiring (1) respectively; and the seal resin (3) is arranged on the circuit wiring (1).

Description

Intelligent power module and manufacturing method thereof Technical field

The present invention relates to the field of electronic device technologies, and in particular, to an intelligent power module and a method of fabricating the same.

Background technique

In the related art, the smart power module is provided with a pin for electrically connecting with an external circuit. However, the intelligent power module is generally used in a harsh working condition, such as an outdoor unit of an inverter air conditioner, and the intelligent power module is usually at a high temperature and high humidity. Working under the condition, the exposed pins are prone to condensation in a humid environment, causing short circuits between the pins. In severe cases, the intelligent power module may explode, causing damage to its application environment and causing significant economic losses. In addition, the smart power module is large in size, large in space and high in cost.

Summary of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, it is an object of the present invention to provide an intelligent power module that is highly reliable, small in size, and low in cost.

Another object of the present invention is to provide a method of manufacturing an intelligent power module.

An intelligent power module according to the present invention, comprising: circuit wiring, at least one end of the circuit wiring is provided with a pad for electrically connecting to an external circuit; a plurality of circuit elements, a plurality of the circuit elements being disposed in the circuit On the upper surface of the wiring, a part of the plurality of circuit elements is a power element, and another part is a driving element corresponding to the power element, and at least one of the driving elements is disposed on the power element corresponding thereto. The power element and the driving element are respectively electrically connected to the circuit wiring; a sealing resin, and the sealing resin is provided on the circuit wiring.

According to the smart power module of the present invention, by arranging the driving component on the power component, the occupied area of the power component and the driving component is effectively saved, the area of the smart power module is reduced, and the volume of the smart power module is reduced. Reduce the cost of intelligent power modules. In addition, by providing a pad at at least one end of the circuit wiring and electrically connecting the external circuit through the pad, the outwardly extending pin on the smart power module in the related art is omitted, and the condensation on the pin is avoided. The short circuit caused by the exposure improves the reliability of the intelligent power module, prolongs the service life of the intelligent power module, and reduces the use cost.

In addition, the intelligent power module according to the invention can also have the following additional technical features:

According to some embodiments of the invention, each of the circuit elements is a planar circuit element, each of the circuit elements The device has electrodes, each of which is electrically connected directly to the circuit wiring by an electrode.

Specifically, the driving component is soldered on the circuit wiring by a first ball, and the power component is soldered to the circuit wiring by the second ball, the height of the first ball is A, The height of the second ball is B, and the A and B satisfy: 400 μm ≤ BA ≤ 500 μm.

Optionally, the driving element has a temperature sensing device for detecting a temperature of the corresponding power element.

According to some embodiments of the invention, the smart power module further includes: a heat sink connected to the upper surface of the power component.

According to some embodiments of the present invention, the sealing resin covers an upper portion of a side surface of the circuit wiring and an upper surface of the circuit wiring, and a lower portion of the side surface of the circuit wiring and a lower surface of the circuit wiring are exposed at The sealing resin is outside.

Specifically, the sealing resin completely covers the circuit component on the upper surface of the circuit wiring, and a side surface of the heat sink away from the power component is exposed outside the sealing resin.

Optionally, the side of the circuit wiring is exposed to a height h outside the sealing resin, and the h satisfies: 0.3 oz≤h≤0.8 oz.

Optionally, the heat sink is a copper sheet, the heat sink has a thickness of t1, and the t1 satisfies: 1.0 mm≤t1≤1.5 mm.

Further, the outer surface of the heat sink has an electroplated silver layer.

Optionally, the thickness of the electroplated silver layer is t2, and the t2 satisfies: 22 μm≤t2≤30 μm.

According to some embodiments of the invention, the circuit wiring is machined from a copper plate having a thickness t3, the t3 satisfying: t3 ≥ 5 ounces.

A method of manufacturing an intelligent power module according to the present invention includes the following steps:

S1: making circuit wiring;

S2: fabricating a base, and digging a groove on the base according to the shape of the circuit wiring, and placing a lower portion of the circuit wiring in the groove;

S3: connecting the driving component to the power component, and electrically connecting the driving component and the power component to the circuit wiring respectively;

S4: packaging the circuit wiring with a sealing resin;

S5: The circuit wiring is taken out from the base to obtain an intelligent power module.

According to the manufacturing method of the intelligent power module of the present invention, by placing the circuit wiring in a recess on the reusable base, positioning the circuit wiring through the base greatly reduces the manufacturing difficulty of the intelligent power module. The manufacturing yield is improved, the cost of the intelligent power module is reduced, and the popularity and application of the intelligent power module are facilitated. In addition, the driving component is disposed on the corresponding power component, which effectively reduces the area and volume of the smart power module, thereby reducing the cost of the smart power module and facilitating miniaturization of the terminal product using the smart power module.

According to some embodiments of the present invention, before the electrodes of the circuit component are connected to the circuit wiring, the method further includes the step of attaching a heat sink to the power component.

Specifically, the step S1 specifically includes the following steps:

S11: stamping or etching the copper plate to form the circuit wiring;

S12: performing an oxidation treatment on the upper surface of the circuit wiring.

Specifically, the step S3 specifically includes the following steps:

S31: coating a non-conductive gel on a lower surface of the power element, the driving element being connected to the power element through the non-conductive gel;

S32: after the circuit wiring is placed in the recess, solder paste is applied to the position of the circuit wiring where the driving component is to be mounted, and a first ball is implanted, and the circuit wiring is to be mounted. The position of the power component is coated with solder paste and implanted with a second ball;

S33: placing the driven electrode on the first ball, and placing an electrode of the power component on the second ball;

S34: fixing the driving component and the power component to the circuit wiring by reflow soldering respectively;

S35: Cleaning the circuit wiring to remove foreign matter remaining on the circuit wiring.

Further, after the circuit wiring is taken out from the base, the method further includes the following steps:

The overflow formed during the sealing of the circuit is removed.

Optionally, the depth of the groove is H, and the H satisfies: 0.3 oz < H < 0.8 oz.

Optionally, the base is a stainless steel piece.

The additional aspects and advantages of the invention will be set forth in part in the description which follows.

DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from

1 is a top plan view of an intelligent power module in accordance with an embodiment of the present invention;

Figure 2 is a cross-sectional view taken along line A-A of Figure 1;

3 is a top plan view of an intelligent power module in which an intelligent power module is removed, in accordance with an embodiment of the present invention Surface sealing resin;

4 is a bottom view of an intelligent power module in accordance with an embodiment of the present invention;

5 is a top plan view of circuit wiring of an intelligent power module in accordance with an embodiment of the present invention;

Figure 6 is a cross-sectional view taken along line B-B of Figure 5;

7 is a schematic structural diagram of a heat sink, a power element, and a driving element of an intelligent power module according to an embodiment of the present invention;

8 is a top plan view of a base in a method of manufacturing an intelligent power module according to an embodiment of the present invention;

9 is a top plan view of a mating of a base and a carrier in accordance with an embodiment of the present invention;

Figure 10 is a cross-sectional view taken along line C-C of Figure 9;

11 is a schematic view of a package sealing resin of an intelligent power module according to an embodiment of the present invention;

FIG. 12 is a bottom view of the smart power module after encapsulating the sealing resin according to an embodiment of the present invention; FIG.

13 is a top plan view of a smart power module packaged with a sealing resin in accordance with an embodiment of the present invention;

14 is a flow chart of a method of fabricating an intelligent power module in accordance with an embodiment of the present invention.

Reference mark:

Intelligent power module 100,

Circuit wiring 1, pad 11,

Circuit component 2, power component 21, drive component 22, sealing resin 3, heat sink 4,

Base 5, groove 51,

Carrier 6, fixed strip 61, overflow glue 7,

Upper mold 81, lower mold 82, gate 83, exhaust port 84,

The first ball 91, the second ball 92.

detailed description

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals are used to refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are intended to be illustrative of the invention and are not to be construed as limiting.

In the description of the present invention, it is to be understood that the terms "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", " The orientation or positional relationship of the indications of "upright", "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the present invention and The simplification of the description is not intended to limit or imply that the device or component that is referred to has a particular orientation, is constructed and operated in a particular orientation, and thus is not to be construed as limiting. In addition, the term "first", "Second" is used for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" and "second" may include one or more of the features either explicitly or implicitly. In the description of the present invention, "a plurality" means two or more unless otherwise stated.

In the description of the present invention, it should be noted that the terms "installation", "connected", and "connected" are to be understood broadly, and may be fixed or detachable, for example, unless otherwise explicitly defined and defined. Connected, or integrally connected; can be mechanical or electrical; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of the two components. The specific meaning of the above terms in the present invention can be understood in a specific case by those skilled in the art.

In the present invention, the first feature "on" or "under" the second feature may include direct contact of the first and second features, and may also include first and second features, unless otherwise specifically defined and defined. It is not in direct contact but through additional features between them. Moreover, the first feature "above", "above" and "above" the second feature includes the first feature directly above and above the second feature, or merely indicating that the first feature level is higher than the second feature. The first feature "below", "below" and "below" the second feature includes the first feature directly above and above the second feature, or merely the first feature level being less than the second feature.

An intelligent power module 100 in accordance with an embodiment of the present invention is described below with reference to FIGS.

The intelligent power module 100 according to an embodiment of the present invention includes: a circuit wiring 1, a plurality of circuit elements 2, and a sealing resin 3. Wherein at least one end of the circuit wiring 1 is provided with a pad 11 for electrical connection with an external circuit; a plurality of circuit elements 2 are provided on the upper surface of the circuit wiring 1, and a part of the plurality of circuit elements 2 is a power element 21 The other part is a driving element 22 corresponding to the power element 21, at least one driving element 22 is disposed on the corresponding power element 21, and the power element 21 and the driving element 22 are electrically connected to the circuit wiring 1, respectively, and the sealing resin 3 is disposed in the circuit. On wiring 1.

According to the smart power module 100 of the embodiment of the present invention, by arranging the driving component 22 on the power component 21, the occupied area of the power component 21 and the driving component 22 is effectively saved, and the area of the smart power module 100 is reduced, thereby reducing The size of the smart power module 100 is reduced, reducing the cost of the smart power module 100. Further, by providing the pad 11 at at least one end of the circuit wiring 1 and electrically connecting to the external circuit through the pad 11, the outwardly extending pins of the smart power module 100 in the related art are omitted, thereby avoiding the introduction. The short circuit caused by the condensation on the foot improves the reliability of the intelligent power module 100, prolongs the service life of the intelligent power module 100, and reduces the use cost.

As shown in FIG. 1 to FIG. 3, the smart power module 100 according to an embodiment of the present invention includes: a circuit wiring 1, a plurality of circuit elements 2, and a sealing resin 3.

Specifically, referring to FIGS. 3-6, at least one end portion of the circuit wiring 1 (for example, the front end in FIG. 3) is provided with a pad 11 for electrical connection with an external circuit. Here, it should be noted that "at least one" as used in the present application refers to one or more. Therefore, the pads 11 are electrically connected to the external circuit, thereby eliminating the outwardly extending pins on the smart power module 100 in the related art, thereby avoiding short circuits caused by condensation on the pins, and improving the smart power module 100. The reliability of the smart power module 100 extends the service life and reduces the cost of use.

Here, referring to FIG. 5 and in conjunction with FIG. 6, the pad 11 may be formed in a square structure, and the longitudinal sectional area of the pad 11 is preferably larger than the longitudinal sectional area of the end portion of the circuit wiring 1. Thereby, the contact area of the pad 11 with the external circuit can be increased, and the reliability of the connection of the smart power module 100 to the external circuit is improved.

A plurality of circuit elements 2 are provided on the upper surface of the circuit wiring 1, and a part of the plurality of circuit elements 2 is the power element 21, and the other part is the driving element 22 corresponding to the power element 21. The power component 21 may be a component having a large amount of heat such as an IGBT transistor or a MOS transistor, and the driving component 22 may be a driving circuit of the power component 21 (for example, an IGBT transistor, a MOS transistor, or the like) corresponding thereto, and the driving component 22 is generally a high voltage. integrated circuit.

Alternatively, each circuit element 2 is a planar type circuit element 2, for example, when the circuit element 2 is an IGBT, an L-type IGBT may be selected. Each circuit element 2 has electrodes, and each circuit element 2 is electrically connected directly to the circuit wiring 1 through an electrode.

Here, the planar type circuit element 2 refers to the circuit element 2 in which all the electrodes are located on the same side surface (for example, the lower surface in FIG. 2) of the circuit element 2. Thereby, the side surface on which the electrode of the circuit component 2 is located is connected to the upper surface of the circuit wiring 1, so that the electrode of the circuit component 2 can be directly connected to the circuit wiring 1, and the electrical connection between the circuit component 2 and the circuit wiring 1 can be realized. The process of realizing the metal wire and the bonding metal wire for electrically connecting the circuit component 2 and the circuit wiring 1 in the related art is omitted, the processing technology of the intelligent power module 100 is simplified, the production efficiency and the production yield are improved, and the saving is achieved. The material cost, equipment cost, and processing cost of the smart power module 100 reduce the overall cost of the smart power module 100.

It is to be understood that the surface on which the electrodes of the planar type circuit component 2 are located may be referred to as "front side" (for example, the lower surface in FIG. 2), and accordingly, the side surface of the planar type circuit component 2 opposite to the electrode It is called "reverse surface" (for example, the upper surface in Figure 2). In the assembly process, the front surface of the circuit component 2 can be connected to the upper surface of the circuit wiring 1, that is, the circuit component 2 can be inverted on the upper surface of the circuit wiring 1.

Specifically, at least one driving element 22 is provided on the corresponding power element 21, and the power element 21 and the driving element 22 are electrically connected to the circuit wiring 1, respectively. Referring to FIGS. 2 and 7, the driving element 22 may be disposed on the lower surface of the power element 21, and the driving element 22 may be directly electrically connected to the circuit wiring 1 through the electrode, and the power element 21 may also be electrically connected directly to the circuit wiring 1 through the electrode. Specifically, the non-conductive gel may be applied on the lower surface of the power element 21 by dispensing or dispensing, and the coated area of the non-conductive gel is slightly larger than the area of the driving element 22. The driving element 22 is then placed on the surface of the non-conductive gel by a DA machine, and the upper surface of the driving element 22 is prevented from coming into contact with the electrodes of the power element 21, and then the non-conductive gel is baked, and the baking temperature can be based on non-conductive The specific material of the gel is adjusted. Generally, the baking temperature should be set at about 125 ° C, and the baking time is 1 to 2 hours to completely solidify the non-conductive gel. The die bond flatness of the drive element 22 can be less than 0.1 mm.

Thus, by locating the driving element 22 on the power element 21 corresponding thereto, the occupied area of the driving element 22 and the power element 21 is effectively reduced, thereby effectively reducing the area and volume of the smart power module 100, and reducing The cost of the smart power module 100. In addition, the area and volume of the terminal product using the power module can be reduced, which is advantageous for miniaturization of the terminal product.

According to some embodiments of the present invention, the driving element 22 may be soldered to the circuit wiring 1 by the first ball 91, and the power element 21 may be soldered to the circuit wiring 1 by the second ball 92, wherein the height of the first ball 91 For A, the height of the second ball 92 is B, and A and B satisfy: 400 μm ≤ BA ≤ 500 μm. Thereby, the power element 21 and the driving element 22 can be easily electrically connected to the circuit wiring 1. The specific heights of the first ball 91 and the second ball 92 can be adjusted according to the specific specifications of the power component 21 and the driving component 22, as long as the power component 21 and the driving component 22 can be electrically connected to the circuit wiring 1. However, the present invention does not specifically limit this. For example, the height A of the first ball 91 and the height B of the second ball 92 may further satisfy: B-A=400 μm, B-A=500 μm, B-A=450 μm, and the like.

Alternatively, the first ball 91 and the second ball 92 may each be a solder ball, but are not limited thereto.

Optionally, the drive element 22 has a temperature sensing device for detecting the temperature of the power element 21 corresponding to the drive element 22. Specifically, the temperature sensing device can be integrated on the driving component 22, and has a simple structure and convenient processing. Therefore, the temperature of the surface of the power component 21 can be monitored in real time by the temperature sensing device, so that when the abnormal power generation phenomenon occurs in the smart power module 100, measures can be taken to respond in time, thereby effectively preventing the intelligent power module 100 from being burnt due to overheating, thereby reducing the The probability of damage of the smart power module 100 improves the reliability of the smart power module 100.

According to some embodiments of the invention, the smart power module 100 further includes a heat sink 4 that is coupled to the upper surface of the power component 21. The heat generation of the power component 21 is large, and the heat sink 4 is connected to the upper surface of the power component 21 to effectively improve the heat dissipation performance of the smart power module 100, thereby improving the reliability of the smart power module 100.

Optionally, the heat sink 4 is a copper piece, which has good heat dissipation effect and low material cost. The thickness of the fin 4 is t1, and t1 satisfies: 1.0 mm ≤ t1 ≤ 1.5 mm. The specific value can be adjusted according to the specific specification and type of the power component 21 to ensure the heat dissipation effect of the heat sink 4. For example, the thickness t1 of the heat sink 4 may further satisfy: t1 = 1.0 mm, t1 = 1.2 mm, or t1 = 1.5 mm, and the like.

According to some embodiments of the invention, the outer surface of the heat sink 4 has an electroplated silver layer. Specifically, it can be used for heat dissipation The outer surface of the sheet 4 is subjected to an electroplating silver treatment to form an electroplated silver layer on the outer surface of the fin 4. Thereby, the wettability of the heat sink 4 can be improved, and the heat radiation effect of the heat sink 4 can be further improved.

Alternatively, the thickness of the electroplated silver layer is t2, and t2 satisfies: 22 μm ≤ t2 ≤ 30 μm. The specific value can be adjusted according to the specific specification and model of the intelligent power module 100. For example, the thickness t2 of the electroplated silver layer may further satisfy: t2 = 22 μm, t2 = 26 μm, or t2 = 30 μm, and the like. Thereby, the wettability of the heat sink 4 can be improved.

The sealing resin 3 is provided on the circuit wiring 1, and the sealing resin 3 is used to encapsulate the circuit wiring 1 to protect the circuit wiring 1 and the circuit component 2 on the circuit wiring 1, thereby improving the reliability of the smart power module 100. Specifically, the sealing resin 3 may be molded by a transfer mold using a thermosetting resin, or may be molded using a thermoplastic resin using an injection mold.

According to some embodiments of the present invention, the sealing resin 3 covers the upper portion of the side surface of the circuit wiring 1 and the upper surface of the circuit wiring 1, and the lower portion of the side surface of the circuit wiring 1 and the lower surface of the circuit wiring 1 are exposed outside the sealing resin 3. 1 and 4, the sealing resin 3 completely covers the circuit component 2 on the upper surface of the circuit wiring 1, and the surface of the heat sink 4 away from the power component 21 is exposed outside the sealing resin 3. Further, the sealing resin 3 covers most of the height of the side surface of the circuit wiring 1, and the small portion of the lower portion of the side surface of the circuit wiring 1 and the lower surface of the circuit wiring 1 are exposed outside the sealing resin 3. That is, all the portions of the upper surface of the circuit wiring 1 excluding the upper surface of the heat sink 4 are covered with the sealing resin 3, and the upper portion of the side surface of the circuit wiring 1 is covered with the sealing resin 3, the lower portion of the side surface of the circuit wiring 1, and the circuit wiring The lower surface of 1 is exposed outside the sealing resin 3.

Thereby, the heat dissipation performance of the smart power module 100 can be effectively improved, the heat accumulation inside the smart power module 100 can be avoided, and the gap between the circuit wires 1 can be completely exposed, thereby making it difficult for moisture to adhere to the circuit wiring 1 In addition, the ions inside the intelligent power module 100 in a high-temperature and high-humidity environment are effectively avoided, for example, chloride ions, bromide ions, etc., which are caused by the migration of water vapor to cause corrosion to the circuit, and the circuit and circuit components of the circuit wiring 1 are avoided. The short circuit of the circuit further improves the reliability of the smart power module 100, prolongs the service life of the smart power module 100, and reduces the use cost of the smart power module 100.

Alternatively, the side of the circuit wiring 1 exposed to the outside of the sealing resin 3 has a height h, h satisfies: 0.3 oz ≤ h ≤ 0.8 oz. For example, the height h of the side of the circuit wiring 1 exposed outside the sealing resin 3 may further satisfy: h = 0.3 ounces, h = 0.4 ounces, h = 0.5 ounces, h = 0.6 ounces, or h = 0.8 ounces, and the like. Thereby, the smart power module 100 facilitates soldering of the solder paste during the subsequent soldering fixing process, so that the circuit wiring 1 exposed outside the sealing resin 3 can be completely wrapped by solder such as solder paste, thereby facilitating assembly of the smart power module 100, The assembly efficiency and assembly reliability of the smart power module 100 are improved.

According to some embodiments of the present invention, the circuit wiring 1 is formed by using a copper plate having a thickness t3 and t3 satisfying: t3 ≥ 5 ounces. For example, the thickness of the copper plate t3 can further satisfy: t3 = 5 ounces, t3 = 6 ounces, t3 = 7 Ounces, etc. Thereby, the contact area of the circuit wiring 1 and the sealing resin 3 can be increased, and the smart power module 100 can be easily fixed.

Specifically, a copper plate having a cross-sectional area of less than 64 mm×30 mm and a thickness of not less than 5 ounces may be selected, and the shape of the circuit wiring 1 is punched out on the copper plate by a stamping die to form the circuit wiring 1; or the high-speed steel may be used as a material by the file. The rotation speed of the control motor is 5000 rpm, so that the boring tool and the plane are formed at right angles to form the shape of the circuit wiring 1. The shape of the circuit wiring 1 can also be etched on the copper plate by a chemical reaction by an etching tool.

Further, an oxidation resistant layer is provided on the outer surface of the circuit wiring 1. Alternatively, the oxidation resistant layer may be a gold layer. For example, a gold layer may be formed on the outer surface of the circuit wiring 1 by means of electroplating gold or chemical immersion gold to improve the oxidation resistance of the circuit wiring 1, so that the smart power module 100 can be applied to a place where the oxidation resistance is high. Thereby, the performance of the smart power module 100 is increased to expand the use range of the smart power module 100.

The smart power module 100 according to the embodiment of the invention has good heat dissipation performance, small area, simple process, high reliability and low cost.

A method of manufacturing the smart power module 100 according to an embodiment of the invention includes the following steps:

S1: making circuit wiring 1;

S2: making the base 5, and digging the groove 51 on the base 5 according to the shape of the circuit wiring 1, placing the lower portion of the circuit wiring 1 in the groove 51;

S3: connecting the driving component 22 to the power component 21, and electrically connecting the driving component 22 and the power component 21 to the circuit wiring 1 respectively;

S4: encapsulating the circuit wiring 1 with a sealing resin 3;

S5: The circuit wiring 1 is taken out from the base 5 to obtain the smart power module 100.

The lower portion of the side surface of the circuit wiring 1 extends into the recess 51, and the upper portion of the side surface of the circuit wiring 1 is exposed outside the recess 51. The width of the groove 51 on the base 5 may be slightly larger than the width of the circuit wiring 1 corresponding thereto in order to place the lower portion of the circuit wiring 1 in the groove 51.

Thereby, the circuit wiring 1 can be positioned by the base 5 to facilitate encapsulation of the sealing resin 3 on the circuit wiring 1, so that the lower and lower surfaces of the side surface of the circuit wiring 1 that protrude into the recess 51 are exposed outside the sealing resin 3. The difficulty in positioning the sealing resin 3 on the circuit wiring 1 is reduced. After the sealing resin 3 is packaged on the circuit wiring 1, the base 5 needs to be taken out, and the base 5 can be reused, thereby eliminating the metal substrate in the smart power module 100 in the related art, thereby further reducing the intelligent power module. The cost of 100.

At the same time, the smart power module 100 completely sealed with respect to the conventional sealed resin 3 reduces the difficulty in controlling the parameters of the thickness of the sealing resin 3 on the upper surface and the lower surface of the circuit wiring 1 during the injection molding, thereby greatly reducing the intelligence. The manufacturing difficulty of the power module 100 increases the manufacturing yield, thereby further reducing the smart power The cost of module 100. In addition, the driving component 22 is disposed on the corresponding power component 21, which effectively reduces the area and volume of the smart power module 100, thereby reducing the cost of the smart power module 100 and facilitating the use of the terminal product of the smart power module 100. Miniaturization.

According to the manufacturing method of the smart power module 100 according to the embodiment of the present invention, by placing the circuit wiring 1 in the recess 51 on the reusable base 5, the circuit wiring 1 is positioned through the base 5, which greatly reduces the smart power. The manufacturing difficulty of the module 100 improves the manufacturing yield, reduces the cost of the smart power module 100, and facilitates the popularization and application of the smart power module 100. In addition, the driving component 22 is disposed on the corresponding power component 21, which effectively reduces the area and volume of the smart power module 100, thereby reducing the cost of the smart power module 100 and facilitating the use of the terminal product of the smart power module 100. Miniaturization.

According to some embodiments of the present invention, before the electrodes of the circuit component 2 are connected to the circuit wiring 1, the method further includes the step of attaching the heat sink 4 to the power component 21. Specifically, the surface of the power element 21 opposite to the surface on which the electrode is located may be attached to the heat sink 4. As shown in FIG. 7, the electrode of the power element 21 is located on the lower surface of the power element 21, and the upper surface of the power element 21 can be mounted on the heat sink 4. Thereby, the heat dissipation performance of the smart power module 100 is effectively improved, and the reliability of the smart power module 100 is improved.

Alternatively, the heat sink 4 may be formed by stamping or etching a copper sheet having a thickness of about 1.5 mm. The outer surface of the heat sink 4 may be plated by silver to form an electroplated silver layer, and then passed through a eutectic. In the process, the power element 21 is mounted on the heat sink 4 with a high temperature solder paste having a melting point of 300 ° C or higher. Among them, the eutectic flatness of the power device can be controlled within 0.1 mm.

Specifically, step S1 specifically includes the following steps:

S11: stamping or etching the copper plate to form the circuit wiring 1;

S12: The upper surface of the circuit wiring 1 is subjected to an oxidation treatment.

Specifically, a copper plate having a cross-sectional area of less than 64 mm×30 mm and a thickness of not less than 5 ounces may be selected, and the shape of the circuit wiring 1 is punched out on the copper plate by a stamping die to form the circuit wiring 1; or by etching a chemical reaction The shape of the circuit wiring 1 is etched on the copper plate. Of course, it can be understood that the high speed steel can be used as a material by the boring tool, and the rotation speed of the motor is controlled to be 5000 rpm, so that the boring tool and the aluminum plane are formed at right angles to form the shape of the circuit wiring 1. Then, the outer surface of the circuit wiring 1 is subjected to an oxidation treatment.

For example, a gold layer may be formed on the outer surface of the circuit wiring 1 by means of electroplating gold or chemical immersion gold to improve the oxidation resistance of the circuit wiring 1, so that the smart power module 100 can be applied to a place where the oxidation resistance is high. Thereby, the use range of the smart power module 100 is expanded.

Of course, it can be understood that when the smart power module 100 is used in a situation where the anti-oxidation requirement is not high, the above step S12 can be omitted to simplify the processing process of the smart power module 100 and reduce the processing cost.

Specifically, step S3 specifically includes the following steps:

S31: coating a non-conductive gel on the lower surface of the power component 21, and the driving component 22 is connected to the power component 21 through a non-conductive gel;

S32: After the circuit wiring 1 is placed in the recess 51, solder paste is applied to the position of the circuit wiring 1 where the driving component 22 is to be mounted, and the first ball 91 is implanted on the power component 21 of the circuit wiring 1 to be mounted. Position the solder paste and implant the second ball 92;

S33: placing the driven electrode on the first ball 91, and placing the electrode of the power component 21 on the second ball 92;

S34: fixing the driving component 22 and the power component 21 to the circuit wiring 1 by reflow soldering respectively;

S35: The circuit wiring 1 is cleaned to remove foreign matter remaining on the circuit wiring 1.

Specifically, after the upper surface of the power component 21 is mounted on the lower surface of the heat sink 4, a non-conductive gel may be applied on the lower surface of the power component 21 by dispensing or dispensing, a non-conductive gel. The coated area is slightly larger than the area of the driving element 22, and then the driving element 22 is placed on the surface of the non-conductive gel by a DA machine, and the upper surface of the driving element 22 is prevented from coming into contact with the electrode of the power element 21, and then the non-conductive condensation is performed. The glue is baked, and the baking temperature can be adjusted according to the specific material of the non-conductive gel. Generally, the baking temperature should be set at about 125 ° C, and the baking time is 1 to 2 hours, so that the non-conductive gel is completely solidified. . The die bond flatness of the drive element 22 can be less than 0.1 mm.

Then, the fabricated circuit wiring 1 is placed in the corresponding groove 51 of the base 5 (as shown in FIG. 8), and the position of the circuit component 1 to be mounted with the driving member 22 is spliced by a solder paste using a steel mesh. Solder paste is applied to the position of the power component 21 to be mounted, respectively. For convenience of description, in the following description of the present application, the position of the circuit wiring 1 on which the driving element 22 is to be mounted is referred to as a "first position", and accordingly, the position of the circuit wiring 1 on which the power element 21 is to be mounted is referred to as " Second position".

Among them, the thickness of the steel mesh may be 0.13 mm to 0.20 mm. After the solder paste is applied in the first position and the second position, the first ball 91 is implanted in the first position and the second ball 92 is implanted in the second position. That is, the driving element 22 and the power element 21 are connected to the circuit wiring 1 by attaching a solder paste to the ball. Optionally, the first ball 91 and the second ball 92 are both solder balls. For example, a stepped steel mesh may be used, and the same thickness of solder paste may be applied to the first position and the second position, and tin balls of different sizes may be implanted, or solder pastes of different thicknesses may be applied in the first position and the second position. For solder balls of the same size, solder pastes of different thicknesses and solder balls of different sizes may be coated on the first position and the second position to connect the driving component 22 and the power component 21 to the first of the circuit wiring 1, respectively. Position and second position.

For example, in accordance with some embodiments of the present invention, referring to Figures 2, 10, and 11, solder paste of the same thickness may be applied at the first location and the second location, and then the first height of the implant A at the first location Ball placement 91, in the second position A second ball 92 having a height of B. Wherein, the height A of the first ball 91 and the height B of the second ball 92 satisfy: 400 μm ≤ B-A ≤ 500 μm.

Then, the electrode of the driving element 22 is placed on the first ball 91 by means of an SMT machine or a DA machine, the electrode of the power element 21 is placed on the second ball 92, and the bottom of the base 5 is placed on the carrier. 6 above, at least one edge of the base 5 is fixed in contact with the carrier 6 (as shown in FIGS. 9 and 10), and the first ball 91 and the second ball 92 are cured by reflow to drive the driving member 22 The power element 21 is fixed to the circuit wiring 1. Thereby, the base 5 can be positioned by the carrier 6 to prevent the base 5 from moving, thereby facilitating the fixing of the circuit component 2 (i.e., the power component 21 and the driving component 22) to the circuit wiring 1 by reflow soldering.

Referring to FIG. 9 in conjunction with FIG. 10, the carrier 6 may be formed in a rectangular shape, and at least one edge of the carrier 6 is provided with a fixing strip 61 which can be pushed from the side edge of the carrier 6 without the fixing strip 61 to the carrier. 6 on. At least one edge of the base 5 is in contact with the carrier 6. Alternatively, the carrier 6 can be made of a material such as synthetic stone, which has high structural strength and low cost.

For example, in the example of FIG. 9, the three edges of the carrier 6 are provided with fixing strips 61 that can be pushed from the edges of the carrier 6 without the fixing strips 61 to the carrier 6.

Here, it should be noted that "SMT" in the present application is an abbreviation of Surface Mount Technology, Chinese can be translated into "surface assembly technology" or "surface mount technology", and SMT machine refers to a slicer. "DA" is the abbreviation of Die Attach, Chinese can be translated as "chip bonding", and DA machine refers to chip bonding machine.

Among them, the reflow time during the reflow process generally does not exceed 10 minutes to prevent the non-conductive gel from melting due to excessive reflow time. In addition, due to the presence of the base 5, even if the non-conductive gel softens, the relative position of the driving element 22 and the power element 21 does not change, and after the reflow process is finished, the non-conductive gel re-hardens to fix the driving element 22 at On the power element 21, the drive element 22 and the power element 21 are not separated.

Specifically, when the circuit wiring 1 is cleaned, the circuit wiring 1 fixed to the chassis 5 can be placed in a cleaning machine for cleaning, and the flux such as rosin remaining during reflow and the aluminum wire remaining during the pressing can be washed. . Specifically, cleaning may be performed according to the arrangement density of the circuit component 2 at the arrangement density of the circuit wiring 1, by spraying or ultrasonic or by a combination of spraying and ultrasonic. During cleaning, the base 5 can be held by the robot arm, and the base 5 can be placed in the cleaning tank for cleaning.

When the amount of flux splashed onto the circuit wiring 1 during the reflow process is small, the flux has little influence on the reliability of the smart power module 100, and the process of cleaning the circuit wiring 1 can be omitted, thereby saving cost.

Further, after the circuit wiring 1 is taken out from the base 5, the method further includes the step of removing the overflow glue 7 formed during the process of sealing the circuit wiring 1.

First, a specific process of encapsulating the sealing resin 3 for the circuit wiring 1 will be described with reference to FIG. Specifically, the sealed tree The grease 3 may be molded by a transfer mold using a thermosetting resin, or may be molded using a thermoplastic resin using an injection mold.

When encapsulating the sealing resin 3, the circuit wiring 1 can be first baked in an oxygen-free environment, the baking time should not be less than 2 hours, and the baking temperature can be selected to be about 125 °C.

Referring to Fig. 11, the package mold includes an upper mold 81 and a lower mold 82, and a cavity is defined between the upper mold 81 and the lower mold 82. The mold cavity has a gate 83 and an exhaust port 84. First, the base 5 on which the circuit wiring 1 is placed is placed in the cavity, and the upper surface of the heat sink 4 is brought into contact with the upper mold 81, and the lower surface of the base 5 is brought into contact with the lower mold 82 to position the circuit wiring 1. At the time of mold clamping, the sealing resin 3 is injected into the cavity from the gate 83, and the gas inside the cavity can be discharged to the outside through the exhaust port 84 during the injection.

In the process of encapsulating the circuit wiring 1 using the sealing resin 3, the portion of the side of the circuit wiring 1 where the groove 51 is exposed, the upper surface of the circuit wiring 1, the circuit component 2 on the upper surface of the circuit wiring 1, and the metal wire are covered with the sealing resin 3. . Due to the action of the pressure, part of the resin enters the recess 51 of the base 5, and an overflow glue 7 is formed on the circuit wiring 1, as shown in FIG. Part of the sealing resin 3 also enters between the fins 4 and the upper mold 81 due to pressure, and adheres to the upper surface of the fins 4 to form an overflow gel 7, as shown in FIG. The thickness of the overflow glue 7 is very thin, generally does not exceed 0.1 mm, and can be removed by using a wind knife or the like, or can be removed by chemical means. Thereby, it is possible to prevent the overflow rubber 7 from affecting the heat dissipation performance of the heat sink 4, and it is possible to prevent the overflow glue 7 from affecting the input and output connection of the circuit wiring 1, and improving the performance of the smart power module 100.

After the overflow gel 7 is removed, the smart power module 100 can be placed in the test equipment for routine electrical parameter testing. Specifically, the contact test can be performed by the thimble and the test point. If the contact test does not pass, the thimble needs to be trimmed until the contact test passes, and then the electrical characteristics test, including the insulation withstand voltage, static power consumption, delay time and other test items, the test is qualified.

Alternatively, the depth of the groove 51 is H, H satisfies: 0.3 oz < H < 0.8 oz. For example, the depth H of the groove 51 may further satisfy: H = 0.3 ounces, H = 0.4 ounces, H = 0.5 ounces, H = 0.6 ounces, or H = 0.8 ounces, and the like. Thereby, the lower portion of the circuit wiring 1 can be inserted into the recess 51 without being covered by the sealing resin 3, and the smart power module 100 can facilitate the soldering of the solder paste in the subsequent soldering and fixing process, so that the solder is exposed outside the sealing resin 3. The circuit wiring 1 can be completely wrapped by solder such as solder paste, thereby facilitating the assembly of the smart power module 100, improving the assembly efficiency and assembly reliability of the smart power module 100.

Optionally, the base 5 is a stainless steel piece. For example, the base 5 can be machined from a high temperature resistant steel having a smooth surface. Thereby, the structural strength and high temperature resistance of the base 5 can be improved, the service life of the base 5 can be prolonged, and the cost of the stainless steel is low, and the material cost can be reduced.

According to the manufacturing method of the smart power module 100 according to the embodiment of the invention, the circuit wiring 1 is positioned by using the reusable base 5, which reduces the difficulty of positioning when encapsulating the sealing resin 3, and greatly reduces the intelligent power module. The manufacturing difficulty of 100 improves the manufacturing yield, reduces the cost of the smart power module 100, and facilitates the popularization and application of the smart power module 100. In addition, after the driving component 22 is connected to the power component 21, the electrode of the driving component 22 and the electrode of the power component 21 are directly connected to the circuit wiring 1, which reduces the area of the smart power module 100, and the related art is omitted. The process of bonding metal wires further saves costs and improves production efficiency.

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example", or "some examples", etc. Particular features, structures, materials or features described in the examples or examples are included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms does not necessarily mean the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

While the embodiments of the present invention have been shown and described, the embodiments of the invention may The scope of the invention is defined by the claims and their equivalents.

Claims (19)

1. An intelligent power module, comprising:

   Circuit wiring, at least one end of the circuit wiring is provided with a pad for electrically connecting to an external circuit;

   a plurality of circuit elements, a plurality of the circuit elements being disposed on an upper surface of the circuit wiring, a portion of the plurality of circuit elements being a power element, and another portion being a driving element corresponding to the power element, at least one The driving component is disposed on the power component corresponding thereto, and the power component and the driving component are respectively electrically connected to the circuit wiring;

   A sealing resin is provided on the circuit wiring.
2. The intelligent power module according to claim 1, wherein each of said circuit elements is a planar type circuit element, each of said circuit elements having electrodes, each of said circuit elements being directly wired to said circuit through electrodes Electrical connection.
3. The intelligent power module according to claim 2, wherein said driving element is soldered to said circuit wiring by a first ball, said power element being soldered to said circuit wiring by said second ball bonding The height of the first ball is A, the height of the second ball is B, and the A, B satisfy: 400 μm ≤ BA ≤ 500 μm.
4. The intelligent power module according to any one of claims 1 to 3, wherein the driving element has a temperature sensing device for detecting a temperature of the corresponding power element.
5. The intelligent power module according to any one of claims 2 to 4, further comprising:

   a heat sink connected to the upper surface of the power component.
6. The intelligent power module according to claim 5, wherein said sealing resin covers an upper portion of a side surface of said circuit wiring and an upper surface of said circuit wiring, a lower portion of said side surface of said circuit wiring, and said The lower surface of the circuit wiring is exposed outside the sealing resin.
7. The intelligent power module according to claim 6, wherein said sealing resin completely covers said circuit component on said upper surface of said circuit wiring, and a side surface of said heat sink away from said power component is exposed The sealing resin is outside.
8. The intelligent power module according to claim 6 or 7, wherein the side of the circuit wiring exposed to the outside of the sealing resin has a height h, and the h satisfies: 0.3 oz≤h≤0.8 oz.
9. The intelligent power module according to any one of claims 5-8, wherein the heat sink is a copper sheet, the heat sink has a thickness t1, and the t1 satisfies: 1.0 mm ≤ t1 ≤ 1.5 mm. .
10. The intelligent power module according to any one of claims 5-9, wherein the outer surface of the heat sink has an electroplated silver layer.
11. The intelligent power module according to claim 10, wherein the thickness of the electroplated silver layer is t2, and the t2 satisfies: 22 μm ≤ t2 ≤ 30 μm.
12. The intelligent power module according to any one of claims 1 to 11, wherein the circuit wiring is processed by a copper plate having a thickness of t3, and the t3 satisfies: t3 ≥ 5 ounces.
13. A method of manufacturing an intelligent power module according to any one of claims 1 to 12, comprising the steps of:

    S1: making circuit wiring;

    S2: fabricating a base, and digging a groove on the base according to the shape of the circuit wiring, and placing a lower portion of the circuit wiring in the groove;

    S3: connecting the driving component to the power component, and electrically connecting the driving component and the power component to the circuit wiring respectively;

    S4: packaging the circuit wiring with a sealing resin;

    S5: The circuit wiring is taken out from the base to obtain an intelligent power module.
14. The method of manufacturing an intelligent power module according to claim 13, wherein before the electrodes of the circuit component are connected to the circuit wiring, the method further comprises the following steps:

    A heat sink is attached to the power component.
15. The method of manufacturing the intelligent power module according to claim 13 or 14, wherein the step S1 comprises the following steps:

    S11: stamping or etching the copper plate to form the circuit wiring;

    S12: performing an oxidation treatment on the upper surface of the circuit wiring.
16. The method of manufacturing the intelligent power module according to any one of claims 13 to 15, wherein the step S3 comprises the following steps:

    S31: coating a non-conductive gel on a lower surface of the power element, the driving element being connected to the power element through the non-conductive gel;

    S32: after the circuit wiring is placed in the recess, solder paste is applied to the position of the circuit wiring where the driving component is to be mounted, and a first ball is implanted, and the circuit wiring is to be mounted. The position of the power component is coated with solder paste and implanted with a second ball;

    S33: placing the driven electrode on the first ball, and placing an electrode of the power component on the second ball;

    S34: fixing the driving component and the power component to the circuit wiring by reflow soldering respectively;

    S35: Cleaning the circuit wiring to remove foreign matter remaining on the circuit wiring.
17. The method of manufacturing the smart power module according to any one of claims 13 to 16, wherein after the circuit wiring is taken out from the base, the method further comprises the following steps:

    The overflow formed during the sealing of the circuit is removed.
18. The method of manufacturing the smart power module according to any one of claims 13-17, wherein the depth of the groove is H, and the H satisfies: 0.3 oz ≤ H ≤ 0.8 oz.
19. The method of manufacturing the smart power module according to any one of claims 13 to 18, wherein the base is a stainless steel member.

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