A high-power rectifier component with low thermal resistance and a manufacturing method thereof

Abstract

The present invention discloses a low thermal resistance high-power rectifier component and a manufacturing method thereof. The low thermal resistance high-power rectifier component comprises a plastic package and a negative metal sheet and a positive metal sheet injected into the plastic package. The bottoms of the negative metal sheet and the positive metal sheet are exposed outside the plastic package. A first rectifier chip and a second rectifier chip are arranged on the negative metal sheet. The positive electrodes of the first rectifier chip and the second rectifier chip are connected to the negative metal sheet. A third rectifier chip and a fourth rectifier chip are arranged on the positive metal sheet. The negative electrodes of the third rectifier chip and the fourth rectifier chip are connected to the positive metal sheet. The low thermal resistance high-power rectifier component and a manufacturing method thereof disclosed by the present invention have a compact and reasonable internal structure arrangement of the component, a small space occupation area, and a reduced external size of the device. At the same time, the exposed size of the heat sink is large, which greatly reduces the thermal resistance of the component, reduces the energy consumption of the product, and improves the heat dissipation efficiency.

Description

Technical Field

[0001] The invention relates to the field of semiconductor devices, and in particular to a low thermal resistance high power rectifying component and a manufacturing method thereof. Background Art

[0002] Electrical appliances used in daily life, such as mobile phones, air conditioners, and microwave ovens, all use DC power. However, in the process of power plants transmitting electricity to users, in order to improve transportation efficiency and avoid power loss during transportation, AC power transmission is adopted in China. Before users use it, AC power needs to be converted into DC power. Usually, bridge rectifier components are widely used in life to achieve this function.

[0003] In the existing technology, for currents of 4A and below, the electronic components of the rectifier bridge have all been surface mounted, and many invention patents have emerged, and their appearance size is becoming thinner and smaller. However, the rectifier components above 4A have always been plug-in type, and the commonly used ones are KBJ, GBU and GBJ (such as Figure 1 As shown in the figure, etc. Because the heat generated by the power components with current above 4A is very large, considering the requirements of safety regulations, the device adopts a full encapsulation method, that is, the plastic package wraps the entire frame. In this way, the thermal resistance of the device is very large and the heat dissipation performance is poor. The heat dissipation capacity of the device itself cannot meet the use requirements. Therefore, in use, it is necessary to install a heat sink on the surface of the device with additional screws, so its surface automatic mounting technology cannot be realized.

[0004] The invention patent with patent number: CN105185757B discloses a low thermal resistance and high power surface mounted rectifier bridge component, the chip arrangement (such as Figure 2 As shown in the figure, A2, A3, A4, and A5 are diode chips) are staggered in the horizontal direction. The safety distance between each electrode is difficult to meet the industry safety rules and standards. The structure is not compact, the product occupies a large space area, the internal structure stress is large, and there is a quality risk of chip breakage at high temperature. Summary of the invention

[0005] The purpose of the present invention is to provide a low thermal resistance and high power rectifier component and a manufacturing method thereof in view of the above-mentioned defects in the prior art. The internal arrangement of the component is reasonable, the space occupied is small, the exposed size of the heat sink is large, the thermal resistance of the component is small, the energy consumption is low, and the heat dissipation efficiency is high.

[0006] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0007] A low thermal resistance and high power rectifier component comprises a plastic package body and a negative electrode metal sheet and a positive electrode metal sheet injection molded in the plastic package body, the bottoms of the negative electrode metal sheet and the positive electrode metal sheet are exposed outside the plastic package body, a first rectifier chip and a second rectifier chip are arranged on the negative electrode metal sheet, the positive electrodes of the first rectifier chip and the second rectifier chip are connected to the negative electrode metal sheet, and a third rectifier chip and a fourth rectifier chip are arranged on the positive electrode metal sheet, the negative electrodes of the third rectifier chip and the fourth rectifier chip are connected to the positive electrode metal sheet.

[0008] In addition, this technical solution also includes the following subsidiary technical solutions:

[0009] A first AC pole metal sheet is also injection molded in the plastic package, a first jumper is mounted on the first rectifier chip and the third rectifier chip, and the first rectifier chip and the third rectifier chip are connected to the first AC pole metal sheet via the first jumper.

[0010] A first copper sheet is arranged between the first rectifier chip and the negative electrode metal sheet, and a second copper sheet is arranged between the third rectifier chip and the first jumper sheet.

[0011] The negative electrode of the first rectifier chip is connected to the first jumper, and the second copper sheet is connected to the first jumper.

[0012] A second AC pole metal sheet is also injection molded in the plastic package, a second jumper is mounted on the second rectifier chip and the fourth rectifier chip, and the second rectifier chip and the fourth rectifier chip are connected to the second AC pole metal sheet via the second jumper.

[0013] A third copper sheet is arranged between the second rectifier chip and the negative electrode metal sheet, and a fourth copper sheet is arranged between the fourth rectifier chip and the second jumper sheet.

[0014] The negative electrode of the second rectifier chip is connected to the second jumper, and the fourth copper sheet is connected to the second jumper.

[0015] In order to achieve the above-mentioned invention object, the present invention also adopts the following technical scheme:

[0016] A method for manufacturing a low thermal resistance and high power rectifier component, providing a first jumper, a second jumper, a first copper sheet, a second copper sheet, a third copper sheet, a fourth copper sheet, a first AC pole metal sheet and a second AC pole metal sheet, the manufacturing method comprising the following steps:

[0017] Step 1: Welding the first rectifier chip and the first copper sheet, the second rectifier chip and the third copper sheet, the third rectifier chip and the second copper sheet, and the fourth rectifier chip and the fourth copper sheet together respectively;

[0018] Step 2: Apply solder paste to the positive metal sheet and the negative metal sheet;

[0019] Step 3: Place the welded first copper sheet and the third copper sheet to the position where the negative electrode metal sheet is coated with solder paste, and place the welded third rectifier chip and the negative electrode of the fourth rectifier chip to the position where the positive electrode metal sheet is coated with solder paste.

[0020] Step 4: Apply solder paste to the negative electrodes of the first rectifier chip and the second rectifier chip, the second copper sheet, and the fourth copper sheet.

[0021] Step 5: Place the first jumper and the second jumper, connect the first rectifier chip and the third rectifier chip to the first AC pole metal sheet through the first jumper; connect the second rectifier chip and the fourth rectifier chip to the second AC pole metal sheet through the second jumper.

[0022] Step 6: Plastic encapsulate the assembled device.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] (1) The internal structure of the components is reasonably laid out, and the smaller dimensions can meet the international safety regulations for high-power devices;

[0025] (2) The large-sized heat sink is exposed, the device has lower thermal resistance, better heat dissipation performance, lower energy consumption and more energy-saving. The heat generated by the chip is directly transferred to the PCB board through the heat sink, which can fully utilize the good heat dissipation performance of the PCB board and heat dissipation tools such as external fans. There is no need to install additional heat sinks in the application, which reduces the customer's use cost;

[0026] (3) The flat layout has a simple structure without bends, which not only reduces the manufacturing cost, but also reduces the internal stress of the material. It will not cause product quality problems such as chip breakage at high temperatures due to structural stress problems.

[0027] (4) The array arrangement is 2 to 4 times more than that of traditional products, the production efficiency is at least doubled, and the production cost can be reduced by more than 35%;

[0028] (5) The product can be applied to automatic placement technology, which no longer requires manual operation and greatly saves labor. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the three most commonly used products with currents above 4A in the current market.

[0030] Figure 2 This is the product structure diagram of the invention patent with patent number CN105185757B.

[0031] Figure 3 It is a front structural schematic diagram of a low thermal resistance and high power rectifier component of the present invention.

[0032] Figure 4 The present invention is a schematic diagram of an exposed heat sink of a low thermal resistance and high power rectifying component.

[0033] Figure 5 The present invention is attached Figure 3 Schematic diagram of the AA cross-section structure.

[0034] Figure 6 The present invention is attached Figure 3 Schematic diagram of the BB cross-section structure.

[0035] Figure 7 This is a traditional product layout diagram.

[0036] Figure 8 The present invention is a layout diagram of a low thermal resistance and high power rectifier component. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described in detail below in conjunction with preferred embodiments and the accompanying drawings.

[0038] like Figures 3 to 6 As shown, a low thermal resistance and high power rectifier component corresponding to the present invention includes a plastic package 5 and a negative electrode metal sheet 1, a positive electrode metal sheet 2, a first AC electrode metal sheet 35 and a second AC electrode metal sheet 42 injected into the plastic package 5, wherein the negative electrode metal sheet 1 serves as a DC negative terminal, the positive electrode metal sheet 2 serves as a DC positive terminal, and the first AC electrode metal sheet 35 and the second AC electrode metal sheet 42 serve as AC power input terminals. The bottoms of the negative electrode metal sheet 1, the positive electrode metal sheet 2, the first AC electrode metal sheet 35 and the second AC electrode metal sheet 42 are coplanarly arranged and are all exposed outside the plastic package 5, wherein the bottoms of the negative electrode metal sheet 1 and the positive electrode metal sheet 2 are exposed outside the plastic package 5 in a large area, and simultaneously play the role of electrical connection and heat dissipation. The edges of the negative electrode metal sheet 1, the positive electrode metal sheet 2, the first AC electrode metal sheet 35 and the second AC electrode metal sheet 42 are all stepped so as to be more firmly combined with the plastic package 5 during plastic packaging.

[0039] A first rectifier chip 31 and a second rectifier chip 32 are arranged on the negative metal sheet 1, and the positive electrodes of the first rectifier chip 31 and the second rectifier chip 32 are connected to the negative metal sheet 1; a third rectifier chip 33 and a fourth rectifier chip 34 are arranged on the positive metal sheet 2, and the negative electrodes of the third rectifier chip 33 and the fourth rectifier chip 34 are connected to the positive metal sheet 2. The rectifier chip is a glass passivated ordinary rectifier chip or a glass passivated fast recovery rectifier chip or a Schottky rectifier chip.

[0040] The first rectifier chip 31 and the third rectifier chip 33 are provided with a first jumper 36, and the first rectifier chip 31 and the third rectifier chip 33 are connected to the first AC pole metal sheet 35 through the first jumper 36 to form a half-wave rectifier bridge. A first copper sheet 38 is provided between the first rectifier chip 31 and the negative pole metal sheet 1, and a second copper sheet 39 is provided between the third rectifier chip 33 and the first jumper 36. Specifically, the negative pole of the first rectifier chip 31 is connected to the first jumper 36, and the second copper sheet 39 is connected to the first jumper 36.

[0041] The second rectifier chip 32 and the fourth rectifier chip 34 are provided with a second jumper 37, and the second rectifier chip 32 and the fourth rectifier chip 34 are connected to the second AC pole metal sheet 42 through the second jumper 37 to form another half-wave rectifier bridge, and the two half-wave rectifier bridges form a full-wave rectifier component. A third copper sheet 40 is provided between the second rectifier chip 32 and the negative pole metal sheet 1, and a fourth copper sheet 41 is provided between the fourth rectifier chip 34 and the second jumper 37. Specifically, the negative pole of the second rectifier chip 32 is connected to the second jumper 37, and the fourth copper sheet 41 is connected to the second jumper 37. By providing the copper sheet, it is not necessary to process the bumps on the frame and the jumper, which greatly reduces the processing difficulty of the frame and the jumper.

[0042] A method for manufacturing a low thermal resistance and high power rectifier component, the manufacturing method comprising the following steps:

[0043] Step 1: Weld the first rectifier chip 31 and the first copper sheet 38, the second rectifier chip 32 and the third copper sheet 40, the third rectifier chip 33 and the second copper sheet 39, and the fourth rectifier chip 34 and the fourth copper sheet 41 together respectively;

[0044] Step 2: Apply solder paste on the positive metal sheet 2 and the negative metal sheet 1;

[0045] Step 3: Place the welded first copper sheet 38 and the third copper sheet 40 to the position where the negative electrode metal sheet 1 is coated with solder paste, and place the welded negative electrodes of the third rectifier chip 33 and the fourth rectifier chip 34 to the position where the positive electrode metal sheet 2 is coated with solder paste.

[0046] Step 4: Apply solder paste to the negative electrodes of the first rectifier chip 31 and the second rectifier chip 32 , the second copper sheet 39 , and the fourth copper sheet 41 .

[0047] Step 5: Place the first jumper 36 and the second jumper 37, connect the first rectifier chip 31 and the third rectifier chip 33 to the first AC pole metal sheet 35 through the first jumper 36; connect the second rectifier chip 32 and the fourth rectifier chip 34 to the second AC pole metal sheet 42 through the second jumper 37.

[0048] Step 6: Plastic encapsulate the assembled device.

[0049] The present invention discloses a high-power rectifier component with low thermal resistance and high power and a manufacturing method thereof. The internal structure layout of the component is reasonable, and the distance between the positive and negative electrodes can meet the requirements of international safety regulations with a very small external size. The large-sized heat sink is exposed, which has better heat dissipation performance, lower energy consumption and more energy saving. The heat generated by the chip is directly transferred to the PCB board through the heat sink, which can fully utilize the good heat dissipation performance of the PCB board and heat dissipation tools such as external fans. In the application, it is no longer necessary to install additional heat sinks, which reduces the customer's use cost. The flat layout is adopted, the structure is simple and there is no bending, which not only reduces the manufacturing cost, but also reduces the internal stress of the material, and will not cause product quality problems such as chip fragmentation at high temperatures due to structural stress problems. The array arrangement (such as Figure 8 ), compared to traditional product arrangements (such as Figure 7 The number of chips (as shown) can be increased by 2 to 4 times, the production efficiency can be at least doubled, and the production cost can be reduced by more than 35%; the product can be applied to automatic patch technology, no longer requiring manual operation, greatly saving labor.

[0050] It should be pointed out that the above preferred embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a low thermal resistance and high power rectifier component, characterized in that: The low thermal resistance and high power rectifier component comprises a plastic package (5) and a negative electrode metal sheet (1) and a positive electrode metal sheet (2) injection-molded in the plastic package (5); the bottoms of the negative electrode metal sheet (1) and the positive electrode metal sheet (2) are exposed outside the plastic package (5); a first rectifier chip (31) and a second rectifier chip (32) are arranged on the negative electrode metal sheet (1); the positive electrodes of the first rectifier chip (31) and the second rectifier chip (32) are connected to the negative electrode metal sheet (1); a third rectifier chip (33) and a fourth rectifier chip (34) are arranged on the positive electrode metal sheet (2); the negative electrodes of the third rectifier chip (33) and the fourth rectifier chip (34) are connected to the positive electrode metal sheet (2); A first AC pole metal sheet (35) is also injection molded in the plastic package (5); a first jumper sheet (36) is mounted on the first rectifier chip (31) and the third rectifier chip (33); the first rectifier chip (31) and the third rectifier chip (33) are connected to the first AC pole metal sheet (35) via the first jumper sheet (36); A second AC pole metal sheet (42) is also injection molded in the plastic package (5); a second jumper (37) is mounted on the second rectifier chip (32) and the fourth rectifier chip (34); the second rectifier chip (32) and the fourth rectifier chip (34) are connected to the second AC pole metal sheet (42) via the second jumper (37); The first AC pole metal sheet (35), the first rectifier chip (31) and the third rectifier chip (33) are aligned and arranged on one side of the plastic package (5), and the first jumper chip (36) is in the shape of a long strip; The second AC pole metal sheet (42), the second rectifier chip (32) and the fourth rectifier chip (34) are aligned and arranged on one side of the plastic package (5), and the second jumper (37) is in the shape of a long strip; A first copper sheet (38) is provided between the first rectifier chip (31) and the negative electrode metal sheet (1), and a second copper sheet (39) is provided between the third rectifier chip (33) and the first jumper sheet (36); A third copper sheet (40) is provided between the second rectifier chip (32) and the negative electrode metal sheet (1), and a fourth copper sheet (41) is provided between the fourth rectifier chip (34) and the second jumper sheet (37); The negative electrode of the first rectifier chip (31) is connected to the first jumper (36), and the second copper sheet (39) is connected to the first jumper (36); The negative electrode of the second rectifier chip (32) is connected to the second jumper (37), and the fourth copper sheet (41) is connected to the second jumper (37); The method for manufacturing a low thermal resistance and high power rectifier component provides a first jumper (36), a second jumper (37), a first copper sheet (38), a second copper sheet (39), a third copper sheet (40), a fourth copper sheet (41), a first AC pole metal sheet (35) and a second AC pole metal sheet (42), and the method comprises the following steps: Step 1: respectively welding together the first rectifier chip (31) and the first copper sheet (38), the second rectifier chip (32) and the third copper sheet (40), the third rectifier chip (33) and the second copper sheet (39), and the fourth rectifier chip (34) and the fourth copper sheet (41); Step 2: Apply solder paste to the positive metal sheet (2) and the negative metal sheet (1); Step 3: placing the welded first copper sheet (38) and the third copper sheet (40) at the position where the negative electrode metal sheet (1) is coated with solder paste, and placing the welded negative electrodes of the third rectifier chip (33) and the fourth rectifier chip (34) at the position where the positive electrode metal sheet (2) is coated with solder paste; Step 4: applying solder paste to the negative electrodes of the first rectifier chip (31) and the second rectifier chip (32), the second copper sheet (39), and the fourth copper sheet (41); Step 5: placing a first jumper (36) and a second jumper (37), connecting the first rectifier chip (31) and the third rectifier chip (33) to the first AC pole metal sheet (35) via the first jumper (36); connecting the second rectifier chip (32) and the fourth rectifier chip (34) to the second AC pole metal sheet (42) via the second jumper (37); Step 6: Plastic encapsulate the assembled device.

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