CN113594103A

CN113594103A - Semiconductor circuit having a plurality of transistors

Info

Publication number: CN113594103A
Application number: CN202110906371.6A
Authority: CN
Inventors: 王敏; 左安超; 谢荣才
Original assignee: Guangdong Huixin Semiconductor Co Ltd
Current assignee: Guangdong Huixin Semiconductor Co Ltd
Priority date: 2021-08-06
Filing date: 2021-08-06
Publication date: 2021-11-02

Abstract

The invention discloses a semiconductor circuit, comprising a box body; the circuit substrate is arranged in the box body; an insulating layer formed on the circuit substrate; a circuit wiring layer formed on the insulating layer; the electronic component is arranged on the circuit wiring layer and is electrically connected with the circuit wiring layer; a packaging layer for sealing the circuit substrate, the insulating layer, the circuit wiring layer and the electronic component; the cover plate is arranged at the opening of the box body; the pin is inserted on the cover plate and is electrically connected with the circuit wiring layer; and the filling seal is arranged on the box body and/or the cover plate and is used for filling thermosetting materials into the box body to form a packaging layer. The semiconductor circuit provided by the invention does not need to use a mould to package the semiconductor circuit, so the manufacturing cost of the semiconductor circuit can be reduced, and the wire punching risk can not be generated when the encapsulating layer is formed by adopting an encapsulating mode. Meanwhile, the pins do not need to be electrically connected through welding, no welding cavity risk exists, the production process is simplified, and the production efficiency is improved.

Description

Semiconductor circuit having a plurality of transistors

Technical Field

The present invention relates to the field of power semiconductors, and more particularly, to a semiconductor circuit.

Background

The semiconductor circuit is a power driving product combining power electronics and integrated circuit technology, integrates an intelligent control IC, high-power devices for power output such as an IGBT, a MOSFET and an FRD and some resistance-capacitance elements, and the devices are welded on an aluminum substrate through tin-based solder.

In the semiconductor circuit packaging process, an insulating layer, a circuit wiring layer, an electronic component, and the like are provided on an aluminum substrate, and then the aluminum substrate is placed in a mold and injection-molded to obtain a resin case for sealing, which encapsulates the aluminum substrate. After the resin casing is thermoset-molded, it needs to be softened again by heating in order to reduce stress.

In the prior art, a die is required to be used for packaging a semiconductor circuit, and the production cost is high. Meanwhile, when the semiconductor circuit is subjected to injection molding and packaging by using a mold, the generated impact force is large, and the risk of line punching exists, namely: the wires of the semiconductor circuit are broken by the impact force or the wires are brought together to cause a short circuit. In addition, the semiconductor circuit requires a step of heating and softening after obtaining the resin case, which also increases the production cost.

Disclosure of Invention

The present invention is directed to a semiconductor circuit, which solves the above problems.

In order to achieve the above object, a main object of the present invention is to provide a semiconductor circuit, including:

the box body is hollow inside;

the circuit substrate is arranged in the box body;

an insulating layer formed on the circuit substrate;

a circuit wiring layer formed on the insulating layer;

the electronic component is arranged on the circuit wiring layer and is electrically connected with the circuit wiring layer;

a packaging layer for sealing the circuit substrate, the insulating layer, the circuit wiring layer, and the electronic component;

the cover plate is arranged at the opening of the box body;

the pin is inserted on the cover plate and is electrically connected with the circuit wiring layer;

and the filling opening is arranged on the box body and/or the cover plate and used for filling thermosetting materials into the box body to form the packaging layer.

Preferably, the pins are arranged in the middle area of the cover plate.

Preferably, the electronic component and the pin are electrically connected to the circuit wiring layer through metal wires, respectively.

Preferably, the pin has a cylindrical shape.

Preferably, the pins are arranged in a step shape.

Preferably, the semiconductor circuit further includes a conductive station layer provided on the circuit wiring layer, and the pin is electrically connected to the circuit wiring layer through the conductive station layer.

Preferably, the encapsulation layer is a soft silica gel layer.

Preferably, the circuit board and the cover plate are fixed to the case by adhesives, respectively.

Preferably, the semiconductor circuit further includes a green oil layer provided on the circuit wiring layer.

Preferably, a through hole matched with the circuit substrate is formed in the box body.

Compared with the prior art, the embodiment of the invention has the beneficial technical effects that:

the semiconductor circuit provided by the invention does not need to use a mould to carry out packaging processing of the semiconductor circuit, so that the manufacturing cost of the semiconductor circuit can be reduced, and the risk of line punching is avoided when the packaging layer is formed by adopting a potting mode. Meanwhile, the pins provided by the invention do not need to be electrically connected through welding, so that the risk of welding cavities is avoided, the production process is simplified, and the production efficiency is improved. And secondly, the pins do not need to be welded with a circuit wiring layer, so that stress does not exist in the middle, and the risk of layering of the insulating layer is reduced. In addition, the semiconductor circuit provided by the invention does not need to coat welding paint at the welding position in advance, and does not need to adopt a step steel mesh, thereby simplifying the process and reducing the cost.

Drawings

FIG. 1 is a schematic diagram of a semiconductor circuit according to an embodiment of the present invention;

FIG. 2 is a top view of the semiconductor circuit shown in FIG. 1;

FIG. 3 is a side view of the semiconductor circuit shown in FIG. 1;

FIG. 4 is a cross-sectional view of the semiconductor circuit shown in FIG. 1;

FIG. 5 is a schematic diagram of a cover plate and leads of the semiconductor circuit shown in FIG. 1;

FIG. 6 is a schematic diagram of the structure of the circuit substrate, the insulating layer, the circuit wiring layer and the electronic components of the semiconductor circuit shown in FIG. 1;

FIG. 7 is a schematic structural diagram of a case of the semiconductor circuit shown in FIG. 1;

FIG. 8 is a schematic structural diagram of a case and a circuit board of the semiconductor circuit shown in FIG. 1;

FIG. 9 is a schematic diagram of a conventional pin structure of a semiconductor circuit;

fig. 10 is a schematic structural diagram of a conventional semiconductor circuit.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be illustrative of the present invention and should not be construed as limiting the present invention, and all other embodiments that can be obtained by one skilled in the art based on the embodiments of the present invention without inventive efforts shall fall within the scope of protection of the present invention.

The semiconductor circuit provided by the invention is a circuit module which integrates a power switch device, a high-voltage driving circuit and the like together and is sealed and packaged on the outer surface, and is widely applied to the field of power electronics, such as the fields of frequency converters of driving motors, various inversion voltages, variable frequency speed regulation, metallurgical machinery, electric traction, variable frequency household appliances and the like. The semiconductor circuit herein may be referred to by various other names, such as Modular Intelligent Power System (MIPS), Intelligent Power Module (IPM), or hybrid integrated circuit, Power semiconductor Module, Power Module, etc. In the following embodiments of the present invention, collectively referred to as a Modular Intelligent Power System (MIPS).

Example one

Referring to fig. 1-8, an embodiment of the invention provides a modular smart power system, including:

the box body 1 is hollow inside;

a circuit board 2 provided in the case 1;

an insulating layer 3 formed on the circuit board 2;

a circuit wiring layer 4 formed on the insulating layer 3;

an electronic component 5 formed on the circuit wiring layer 4 and electrically connected to the circuit wiring layer 4;

a sealing layer 6 for sealing the circuit substrate 2, the insulating layer 3, the circuit wiring layer 4, and the electronic component 5;

the cover plate 7 is arranged at the opening of the box body 1;

the pin 8 is inserted on the cover plate 7 and is electrically connected with the circuit wiring layer 4;

and the filling opening 9 is arranged on the box body 1 and/or the cover plate 7 and is used for filling thermosetting materials into the box body 1 to form the packaging layer 6.

In the present embodiment, the circuit substrate 2 serves as a carrier of an internal circuit of the modular smart power system, and is used for disposing the insulating layer 3, the circuit wiring layer 4, the electronic component 5, and the like, and preferably, the circuit substrate 2 proposed in the present embodiment is a metal plate, such as a copper plate or a ceramic plate. Furthermore, the circuit substrate 2 has good heat dissipation performance so as to dissipate heat generated by the modular intelligent power system to the outside in time. In order to prevent the internal circuit from short circuit and leakage, the present embodiment provides the insulating layer 3 on the circuit substrate 2, and the insulating layer 3 isolates the circuit substrate 2 from the circuit wiring layer 4 to prevent the circuit wiring layer 4 from being electrically connected to the circuit substrate 2.

The circuit wiring layer 4 mainly functions to provide and electrically connect the electronic component 5, and the circuit wiring layer 4 is provided on the insulating layer 3, and is formed on the insulating layer 3 by etching. Specifically, a copper foil layer is laid on the insulating layer 3, and the copper foil layer is etched to form a desired circuit, thereby preparing the circuit wiring layer 4.

And mounting positions of the electronic components 5 are reserved on the copper foil layer, so that each electronic component 5 can be correspondingly mounted. Specifically, for example, a semiconductor chip is first coated with solder paste or silver paste, and then the chip of the modular intelligent power system is mounted on the mounting position by automatic die bonding equipment (DA machine). And for the resistance-capacitance piece, the resistance-capacitance piece is mounted on the mounting position through an automatic chip mounting machine (SMT).

The main function of the encapsulation layer 6 is to seal the circuit substrate 2, the insulating layer 3, the circuit wiring layer 4, the electronic component 5 and the like, so as to isolate the circuit substrate from the external environment, and avoid the external environment from affecting the modular intelligent power system. For example, the package layer 6 can prevent dust, water and other impurities in the external environment from contacting the modular intelligent power system, and prolong the service life of the modular intelligent power system.

In this embodiment, the encapsulating layer 6 is obtained by potting the potting cap 9, after the opening of the case 1 is sealed by the lid plate 7, the sealing material is injected through the potting cap 9, the sealing material flows inside the case 1, and then the sealing material is cured to obtain the encapsulating layer 6, and the encapsulating layer 6 covers all of the circuit board 2, the insulating layer 3, the circuit wiring layer 4, the electronic component 5, and the like.

The packaging process of the modular intelligent power system provided by the embodiment comprises the following steps: the method comprises the steps of preparing a circuit substrate 2 through a metal substrate, forming an insulating layer 3 on the circuit substrate 2, forming a circuit wiring layer 4 on the insulating layer 3, and finally arranging an electronic component 5 on the circuit wiring layer 4. After obtaining the circuit substrate 2, the circuit substrate is installed in the box body 1, then the cover plate 7 inserted with the pins 8 is covered at the opening of the box body 1, finally, the sealing material is injected into the box body 1 through the filling seal 9, the sealing material flows and solidifies in the box body 1, and then the packaging layer 6 is obtained.

The box body 1 and the cover plate 7 in the modular intelligent power system provided by the embodiment have the functions of a mold, so that the mold does not need to be reused during packaging and processing, and the aim of reducing the production cost can be fulfilled. In addition, when the encapsulation layer 6 is formed, the modular smart power system proposed in this embodiment performs encapsulation by using an encapsulation machine without using an injection molding machine, and since the price of the injection molding machine is much higher than that of the encapsulation machine, the manufacturing cost of the modular smart power system proposed in this embodiment can be further reduced.

Furthermore, the pin 8 provided by the embodiment is inserted into the cover plate 7, and is not required to be welded with the circuit wiring layer 4, so that the risk of welding holes is avoided, the production process is simplified, and the production efficiency is improved. Referring to fig. 9, when the conventional modular intelligent power system is packaged in a mold, in order to prevent the electronic component 5 from being damaged by static electricity in the subsequent processing procedure, the specific positions of the pins 8 need to be connected through reinforcing ribs, and therefore, the reinforcing ribs need to be cut off through rib cutting equipment after the packaging is completed. The pin 8 provided by the embodiment does not need to be provided with a reinforcing rib structure, so that the redundant dummy pin 8 and reinforcing ribs do not need to be cut by rib cutting equipment, and the manufacturing cost of the modular intelligent power system is reduced. In addition, the phenomenon of copper leakage caused by cutting off of the pins 8 can be avoided, and the reliability of the product is not influenced.

Since the pins 8 do not need to be soldered to the circuit wiring layer 4, there is no stress in the middle, reducing the risk of delamination of the insulating layer 3. In addition, the modularized intelligent power system provided by the invention does not need to coat welding paint at the welding position in advance, and does not need to adopt a ladder steel mesh, so that the process is simplified, and the cost is reduced.

Furthermore, the lead 8 proposed in the embodiment adopts C194(-1/2H) (chemical composition: Cu is more than or equal to 97.0 Fe: 2.4P: 0.03 Zn: 0.12) or KFC (-1/2H) (chemical composition: Cu is more than or equal to 99.6 Fe: 0.1 (0.05-0.15) P: 0.03 (0.025-0.04)), and the C194 or KFC cylindrical copper material with the diameter of 0.5mm is machined, and then the surface is plated with nickel with the thickness of 0.1-0.5um, and then the surface is plated with tin with the thickness of 2-5 um.

Furthermore, the number of the pins 8 provided in this embodiment is multiple, the pins 8 are respectively inserted into the cover plate 7, and the pins 8 are distributed at a preset distance. Two ends of the pin 8 respectively penetrate through two sides of the cover plate 7, one end of the pin 8 is exposed in the box body 1 and is in contact (electrical connection) with the circuit wiring layer 4, and the other end of the pin 8 is exposed outside the box body 1 and is used for being electrically connected with the electric control board.

Example two

Referring to fig. 1, 2 and 5, the lead 8 according to the embodiment of the present invention is disposed in the middle region of the cover plate 7. In this embodiment, the pins 8 are disposed at the middle position of the cover plate 7, and are used as input/output metal pins 8 connected with the circuit wiring and extending outwards. Referring to fig. 10, the pins 8 of the conventional modular smart power system are generally disposed at the left and right edges thereof, which results in long internal circuit routing distance, inflexible circuit layout, and poor interference resistance, but in the embodiment, the pins 8 are disposed in the middle region of the cover plate 7, and the pins 8 pass through the cover plate 7 and then contact with the middle region of the circuit wiring layer 4, so as to achieve electrical connection between the pins 8 and the circuit wiring layer 4. Because the pin 8 that this embodiment proposed sets up in the middle part region of apron 7, consequently, the inside line distance of walking of modularization intelligent power system will obviously shorten, because pin 8 just need not to extend to the left and right sides at the intermediate position, directly walk the line along vertical direction can.

EXAMPLE III

Referring to fig. 4, the electronic component 5 and the leads 8 according to the embodiment of the invention are electrically connected to the circuit wiring layer 4 through metal wires 10, respectively. In this embodiment, the electronic component 5 is electrically connected to the electronic component 5 through a metal wire 10, for example, the semiconductor chip is electrically connected to the rc element through the metal wire 10, one end of the metal wire 10 is bonded to the semiconductor chip, and the other end of the metal wire 10 is bonded to the rc element. The electronic component 5 and the circuit wiring layer 4 are also electrically connected by a metal wire 10, one end of the metal wire 10 is electrically connected to the electronic component 5, and the other end of the metal wire 10 is electrically connected to the circuit wiring layer 4.

Example four

Referring to fig. 1-3 and 5, the pin 8 according to the embodiment of the present invention is cylindrical. In this embodiment, pin 8 is set up to cylindrical structure, and current modularization intelligent power system's pin 8 is square structure usually, and the cylindrical structure that this embodiment provided does not need the installation hole site shape on the automatically controlled board when carrying out automatically controlled assembly, and it is more convenient to install, and rectangular pin 8 just will divide minor face and long limit, so the mounting hole that corresponds also has some differentiation.

EXAMPLE five

Referring to fig. 1-3 and 5, the pins 8 according to the embodiment of the present invention are arranged in a step shape. In this embodiment, the cylindrical pin 8 includes a first connection section and a second connection section, and a stepped structure is formed between the first connection section and the second connection section, which is similar to a stepped shaft structure. Namely: the diameter of the first connecting section is different from that of the second connecting section, so that the leakage length of the back pin 8 is limited when the modular intelligent power system is assembled on the electric control board. Furthermore, the thickness of the electric control board is generally 1-2mm, and the length of the pin 8 extending out of the electric control board after the pin 8 is installed on the electric control board is 0.5-1mm, so that the length of the second connecting section is 1.5-3 mm. The second connection section is a portion of the pin 8 completely exposed outside the case 1, the first connection section is partially exposed outside the case 1, and the other portion is exposed inside the case 1 and electrically connected to the circuit wiring layer 4.

EXAMPLE six

Referring to fig. 4, the modular smart power system of the present embodiment further includes a conducting stage 20 disposed on the circuit wiring layer 4, and the pins 8 are electrically connected to the circuit wiring layer 4 through the conducting stage 20. In this embodiment, the conductive step layer 20 is used to realize electrical connection between the metal line 10 and the pin 8, and because the pin 8 is a cylindrical structure, the metal line 10 cannot be directly bound to the cylindrical pin 8, and only the metal line 10 is bound to a flat surface of an intermediate medium through the intermediate medium, and then the pin 8 contacts with the flat surface, so as to realize electrical connection between the metal line 10 and the pin 8. Preferably, the conductive step layer 20 proposed in the present embodiment is a copper foil step.

EXAMPLE seven

Referring to fig. 4, the encapsulation layer 6 according to the embodiment of the invention is a soft silicone layer. In this embodiment, the encapsulation layer 6 is a soft silica gel layer, that is, the encapsulation layer 6 is formed by encapsulation of soft silica gel. Soft silicone, i.e. heat conducting silicone, is a high end heat conducting compound and does not solidify, the property of not conducting electricity can avoid risks such as short circuit of the circuit. The soft silica gel is a single-component, heat-conducting and room-temperature-curing organosilicon adhesive sealant, is vulcanized into a high-performance elastomer by crosslinking and curing through condensation reaction of water in the air to release low molecules, and has excellent cold and heat alternation resistance, aging resistance and electrical insulation performance, as well as excellent moisture resistance, shock resistance, corona resistance, electric leakage resistance and chemical medium resistance. The adhesive has no swelling and good adhesion to most of metal and non-metal materials, and can play a role in high adhesion and super heat conduction on electronic components and devices. The encapsulation layer 6 provided by the embodiment of the invention is formed by soft silica gel encapsulation, so that the encapsulation layer is soft in texture, and even if the encapsulation layer is cured in the encapsulation process, the encapsulation layer does not cause large impact on a circuit, thereby avoiding the risk of line punching.

Example eight

Referring to fig. 1 and 5-8, the circuit board 2 and the cover plate 7 according to the embodiment of the present invention are respectively fixed to the case 1 by an adhesive. In this embodiment, before the circuit substrate 2 is placed inside the box body 1, a layer of adhesive is applied to the mounting position of the circuit substrate 2, and then the circuit substrate 2 is placed on the mounting position, and then the adhesive is cured at a high temperature, so that the circuit substrate 2 is fixed inside the box body 1. Meanwhile, a layer of adhesive is coated on the edge surface of the upper opening of the box body 1, then the cover plate 7 inserted with the pins 8 is placed at the opening of the box body 1, and then the adhesive is cured at high temperature, so that the cover plate 7 is fixed at the opening of the box body 1.

Example nine

Referring to fig. 9, the modular smart power system according to the embodiment of the present invention further includes a green oil layer disposed on the circuit wiring layer 4. In the present embodiment, the copper foil layer is etched to form a desired circuit, and in order to isolate the circuit etched on the copper foil layer from the outside, a green oil layer is provided on the circuit wiring layer 4 to protect the circuit by the green oil layer.

Example ten

Referring to fig. 7, a through hole 11 adapted to the circuit substrate 2 is disposed inside the case 1 according to the embodiment of the present invention. In this embodiment, when the circuit board 2 is installed inside the box body 1, in order to ensure that the circuit board 2 can be accurately installed in place, the through hole 11 is formed in the middle position inside the box body 1, and the size of the through hole 11 is matched with the size of the circuit board 2. When the circuit board 2 is mounted in the case 1, the circuit board 2 is inserted into the through hole 11 from the bottom of the case 1, and the circuit board 2 and/or the side wall of the through hole 11 are/is fixed by applying an adhesive to the side wall and curing the adhesive at a high temperature.

The manufacturing method of the modular intelligent power system provided by the invention comprises the following steps:

firstly, putting a prepared metal substrate into a special carrier (the carrier can be made of materials with high temperature resistance of more than 200 ℃ such as aluminum, synthetic stone, ceramics, PPS and the like), pasting a chip of a modular intelligent power system on a mounting position of an electronic component 5 reserved on a copper foil layer through automatic crystal pasting equipment (DA machine) in a mode of brushing tin paste or dispensing silver paste, pasting a capacitance-resisting piece on the mounting position through automatic Surface Mount Technology (SMT), and then, enabling the whole semi-finished product including the carrier to pass through a reflow oven together so as to weld all the electronic components 5 on corresponding mounting positions.

After the soldering is completed, the soldering quality of the electronic component 5 is detected by visual inspection equipment (AOI), foreign matters such as flux and aluminum chips remaining on the circuit board 2 are removed by cleaning methods such as spraying and ultrasonic, and the electronic component 5 is electrically connected to the circuit wiring layer 4 and the copper foil step by the metal wire 10. Brushing a layer of adhesive on the mounting positions of the circuit substrate 2 in the box body 1, then placing the circuit substrate 2 bound with the metal wires 10 on the corresponding mounting positions, and enabling the technical edge of the circuit substrate 2 to be in contact with the adhesive brushed on the box body 1.

Simultaneously, scribble the one deck bonding medium on the last border surface of box body 1, then will have apron 7 of pin 8 to place the surface of box body 1, make apron 7 and box body 1 contact, then make circuit substrate 2 and apron 7 fix to box body 1 through high temperature curing, then seal 9 through irritating and pour into box body 1 inside with soft silica gel, make soft silica gel cover whole modularization intelligent power system's electronic components 5 and metal wire 10, then carry out the selective examination to the embedment condition inside through X-ray, the certified products is through beating the mark, electrical parameter test forms the final product.

The above is only a part or preferred embodiment of the present invention, and neither the text nor the drawings should limit the scope of the present invention, and all equivalent structural changes made by the present specification and the contents of the drawings or the related technical fields directly/indirectly using the present specification and the drawings are included in the scope of the present invention.

Claims

1. A semiconductor circuit, comprising:

the box body is hollow inside;

the circuit substrate is arranged in the box body;

an insulating layer formed on the circuit substrate;

a circuit wiring layer formed on the insulating layer;

the cover plate is arranged at the opening of the box body;

2. The semiconductor circuit of claim 1, wherein the pin is disposed in a central region of the cover plate.

3. The semiconductor circuit according to claim 1, wherein the electronic component and the pin are electrically connected to the circuit wiring layer through metal wires, respectively.

4. The semiconductor circuit of claim 3, wherein the pin has a cylindrical shape.

5. The semiconductor circuit of claim 4, wherein the pins are arranged in a step shape.

6. The semiconductor circuit of claim 4, further comprising a conductive station layer disposed on the circuit wiring layer, the pin being electrically connected to the circuit wiring layer through the conductive station layer.

7. The semiconductor circuit of claim 1, wherein the encapsulation layer is a soft silicone layer.

8. The semiconductor circuit according to claim 1, wherein the circuit board and the cover plate are fixed to the case by adhesives, respectively.

9. The semiconductor circuit according to claim 1, further comprising a layer of green oil provided on the circuit wiring layer.

10. A semiconductor circuit according to any of claims 1 to 9, wherein the box body is provided with a through hole therein which is adapted to the circuit substrate.