SiC device connected by copper connecting sheet

Abstract

The utility model relates to the technical field of power semiconductor devices, in particular to a SiC device connected by copper connecting sheets. Comprising a SiCmos chip, a plastic package shell, a first frame part and a second frame part, a drain electrode part of the SiCmos chip is electrically connected with a drain pin part of the first frame part, a source electrode part of the SiCmos chip is electrically connected with a source pin part of the second frame part, and a gate electrode part of the SiCmos chip is electrically connected with a gate pin part of the second frame part. And the copper connecting sheet is formed by bending a copper sheet and comprises a first connecting section, a bending section and a second connecting section. Compared with the prior art, the utility model has the advantages that the overcurrent capability of the copper connecting sheet is stronger than that of an aluminum bonding wire, and the parasitic resistance of the copper connecting sheet is smaller than that of the aluminum bonding wire, so that the bonding wire can be prevented from falling off and fusing, and the reliability of the SiC device is enhanced. The copper connecting sheet can reduce transient thermal resistance of the device, and the device can output higher power instantaneously.

Description

Technical Field

[0001] The utility model relates to the technical field of power semiconductor devices, in particular to a SiC device connected by a copper connecting sheet. Background Art

[0002] Power semiconductors are the most critical devices in the power electronics industry and can be used in a variety of circuits to achieve power conversion, inversion, rectification, etc. They are widely used in industrial control, rail transportation, consumer electronics, new energy vehicles and other fields.

[0003] Power semiconductor devices are currently developing in the direction of high power density, and the electrical connection method of traditional discrete devices is still aluminum bonding wires. For example, the applicant's prior patent application 202122101537.5 has an electronic device with a packaging structure for top surface heat dissipation. There are certain technical defects in the technical solution proposed in this patent. The technical solution uses aluminum bonding wires, which have high resistivity and poor overcurrent capability. When the current is too large, heat concentration will occur. During reliability testing, failure modes caused by broken aluminum bonding wires are prone to occur. Therefore, aluminum bonding wires are difficult to meet the needs of high power density. Utility Model Content

[0004] The utility model aims to overcome the deficiencies of the prior art and provide a SiC device connected by a copper connecting sheet to improve the power density and reliability of the device.

[0005] In order to achieve the above purpose, a SiC device connected by copper connecting sheets is designed.

[0006] It includes a SiCmos chip, a plastic package shell, a first frame part and a second frame part, the drain electrode part of the SiCmos chip is electrically connected to the drain pin part of the first frame part, the source electrode part of the SiCmos chip is electrically connected to the source pin part of the second frame part, and the gate electrode part of the SiCmos chip is electrically connected to the gate pin part of the second frame part.

[0007] It also includes a copper connecting piece, which is made by bending a piece of copper sheet. The copper connecting piece includes a first connecting section, a bent section, and a second connecting section. The first connecting section of the copper connecting piece is welded to the source electrode portion of the SiCmos chip, the bent section of the copper connecting piece is bent close to the plastic package shell, and the second connecting section of the copper connecting piece is welded to the source pin portion on the second frame portion. The width of the second connecting section of the copper connecting piece is greater than the width of the first connecting section.

[0008] The drain electrode connection structure of the SiCmos chip has the following characteristics: the lower surface of the SiCmos chip is soldered to the drain pin of the first frame by using solder paste material.

[0009] The gate electrode portion of the SiCmos chip is connected to the gate lead portion of the second frame portion through a bonding wire.

[0010] Compared with the prior art, the utility model has the following advantages:

[0011] The copper connecting piece has a much stronger overcurrent capability than the aluminum bonding wire, and its parasitic resistance is also smaller than that of the aluminum bonding wire. When the same current is passed, the heat generated by the copper connecting piece is smaller than that of the aluminum bonding wire, which can avoid failure modes such as the aluminum bonding wire falling off and melting, and enhance the reliability of the SiC device. At the same time, the copper connecting piece is made of copper material and has a certain thermal capacity. During the application process, the transient thermal resistance of the SiC device can be reduced, helping the SiC device to output more power instantaneously to meet higher power application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 , is a front structural schematic diagram of the utility model;

[0013] Figure 2 , is a side structural schematic diagram of the utility model.

[0014] In the figure: 10 SiC MOS chip; 11 drain electrode; 12 source electrode; 13 gate electrode; 20 plastic package; 30 frame; 31 first frame; 310 drain pin; 32 second frame; 320 source pin; 321 gate pin; 40 copper connection sheet; 41 bonding wire; 50 solder paste material. DETAILED DESCRIPTION

[0015] In order to make the purpose, principle and structure of the utility model clearer, it is further described below in conjunction with the drawings and specific embodiments.

[0016] The utility model provides a SiC device connected by a copper connecting piece.

[0017] It includes a SiCmos chip, a plastic package shell, a first frame part and a second frame part, the drain electrode part of the SiCmos chip is electrically connected to the drain pin part of the first frame part, the source electrode part of the SiCmos chip is electrically connected to the source pin part of the second frame part, and the gate electrode part of the SiCmos chip is electrically connected to the gate pin part of the second frame part.

[0018] It also includes a copper connecting piece, which is made by bending a piece of copper sheet. The copper connecting piece includes a first connecting section, a bent section, and a second connecting section. The first connecting section of the copper connecting piece is welded to the source electrode portion of the SiCmos chip, the bent section of the copper connecting piece is bent close to the plastic package shell, and the second connecting section of the copper connecting piece is welded to the source pin portion on the second frame portion. The width of the second connecting section of the copper connecting piece is greater than the width of the first connecting section.

[0019] The drain electrode connection structure of the SiCmos chip has the following characteristics: the lower surface of the SiCmos chip is soldered to the drain pin of the first frame by using solder paste material.

[0020] The gate electrode portion of the SiCmos chip is connected to the gate lead portion of the second frame portion through a bonding wire.

[0021] Specifically:

[0022] like Figure 1 , Figure 2 As shown, the utility model is a SiC device connected by copper connecting wires. Figure 1 , Figure 2 They are front and side structural schematic diagrams of the utility model, respectively, including a SiCmos chip 10, a plastic package shell 20, a frame 30, a copper connecting sheet 40, a bonding wire 41, and a solder paste material 50.

[0023] The lower surface of the SiCmos chip 10 has a drain electrode portion 11, and the upper surface has a source electrode portion 12 and a gate electrode portion 13. The plastic package shell 20 covers the SiCmos chip 10. The frame 30 includes a first frame portion 31 and a second frame portion 32, the first frame portion 31 and the second frame portion 32 are isolated from each other, and the SiCmos chip 10 is soldered to the first frame portion 31 through the solder paste material 50 to achieve electrical connection between the drain electrode portion 11 of the SiCmos chip 10 and the drain pin portion 310 on the first frame portion 31. The two sides of the copper connecting sheet 40 are respectively soldered to the source electrode portion 12 of the SiCmos chip 10 and the source pin portion 320 on the second frame portion 32 through the solder paste material 50 to achieve electrical connection between the source electrode portion 12 of the SiCmos chip 10 and the source pin portion 320 on the second frame portion 32. The two sides of the bonding wire 41 are respectively ultrasonically welded to the gate electrode portion 13 of the SiCmos chip 10 and the gate pin portion 321 on the second frame portion 32, thereby realizing the electrical connection between the gate electrode portion 13 of the SiCmos chip 10 and the gate pin portion 321 on the second frame portion 32. The drain pin portion 310 is connected to the positive electrode of the external power supply, the source pin portion 320 is connected to the negative electrode of the external power supply, and the gate pin portion 321 is connected to the external gate signal.

[0024] The copper connecting piece 40 has a much stronger overcurrent capability than the aluminum bonding wire, and its parasitic resistance is also smaller than that of the aluminum bonding wire. When the same current is passed, the heat generated by the copper connecting piece 40 is smaller than that of the aluminum bonding wire, which can avoid failure modes such as the aluminum bonding wire falling off and melting, and enhance the reliability of the SiC device. At the same time, the copper connecting piece 40 is made of copper material and has a certain thermal capacity. During the application process, the transient thermal resistance of the SiC device can be reduced, helping the SiC device to output more power instantaneously to meet higher power application scenarios.

[0025] The above is only a specific implementation method of this utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field within the technical scope disclosed by the utility model, according to the technical solution and new concept of the utility model, shall be covered by the protection scope of the utility model.

Claims

1. A SiC device connected by a copper connecting sheet, comprising a SiCmos chip, a plastic package, a first frame portion and a second frame portion, wherein the drain electrode portion of the SiCmos chip is electrically connected to the drain pin portion of the first frame portion, the source electrode portion of the SiCmos chip is electrically connected to the source pin portion of the second frame portion, and the gate electrode portion of the SiCmos chip is electrically connected to the gate pin portion of the second frame portion, characterized in that Also includes A copper connecting piece, wherein the copper connecting piece is formed by bending a piece of copper sheet, the copper connecting piece comprises a first connecting section, a bending section and a second connecting section, the first connecting section of the copper connecting piece is welded to the source electrode portion of the SiCmos chip, the bending section of the copper connecting piece is bent close to the plastic package shell, the second connecting section of the copper connecting piece is welded to the source pin portion on the second frame portion, and the width of the second connecting section of the copper connecting piece is greater than the width of the first connecting section.

2. A SiC device connected by a copper connecting piece according to claim 1, characterized in that The drain electrode connection structure of the SiCmos chip has the following characteristics: the lower surface of the SiCmos chip is soldered to the drain pin of the first frame by using solder paste material.

3. A SiC device connected by a copper connecting piece according to claim 1, characterized in that The gate electrode portion of the SiCmos chip is connected to the gate lead portion of the second frame portion through a bonding wire.

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