Ultra-thin-type surface-mount rectifier

Abstract

The invention discloses an ultra-thin-type surface-mount rectifier. A diode chip of the surface-mount rectifier comprises a heavily-doped P-type monocrystalline silicon wafer whose surface is equipped with a heavily-doped N-type region; the heavily-doped N-type region is contacted with the heavily-doped P-type monocrystalline silicon wafer; grooves are formed at the periphery of the heavily-doped N-type region; the grooves are located at the peripheries of the heavily-doped P-type monocrystalline silicon wafer and the heavily-doped N-type region and extend to a middle part of the heavily-doped P-type monocrystalline silicon wafer; a bottom part of an epoxy package body is equipped with a strip-shaped raised insulation part; the strip-shaped raised insulation part is located between a pin region of a first lead strip and a pin region of a second lead strip; and two side surfaces of the strip-shaped raised insulation part are respectively equipped with a first arc-shaped concave region and a second arc-shaped concave region. Through the abovementioned mode, a contact area is increased, a contact region of a connecting piece and a lead is increased by more than 65%, and the welding strength of a diode device and a PCB (Printed Circuit Board) is improved.

Description

Technical field [0001] The invention relates to the field of rectifier devices, in particular to an ultra-thin surface mount rectifier. Background technique [0002] The ultra-thin surface mount rectifier is an electronic device with unidirectional current conduction. The existing ultra-thin surface mount rectifier mainly has the following technical problems: On the one hand, the internal material connection method of the device is mainly through the soldering tab at high temperature The bottom melting connects the chip and the lead firmly, but it is difficult to achieve 100% fusion between the copper lead and the solder. Usually the effective welding area of ​​the chip and the connecting piece is 85%, and the lead is only about 60%, resulting in When a large current passes, the current distribution is uneven, which reduces the ability of the product to withstand surges. "Welding" is a key process in the production of rectifier devices, especially diode rectifier devices. Whethe...

AI Technical Summary

Problems solved by technology

[0002] The ultra-thin surface-mount rectifier is an electronic device with unidirectional current conduction. The existing ultra-thin surface-mount rectifier mainly has the following technical problems: On the one hand, the internal material connection method of the device is mainly through the solder tab at high temperature. The lower melting connects the chip and the lead firmly together, but it is difficult to achieve 100% fusion of the copper lead and the solder. Usually, the effective welding area of ​​the chip and the connecting piece is 85%, while the end of the lead is only about 60%. When a large current passes, the current distribution is uneven, which reduces the ability of the product to withstand surges

Due to the irregular shape of the solder pad after high temperature, the distance between the four sides of the chip and the chip after melting is less than 0.2mm. Once the position of the chip and the solder pad is slightly inclined or the welding temperature and welding speed have a slight deviation, the solder will flow down to the chip. At the edge of the chip, so as to touch the other side of the chip, the flowing solder will become a wire, and the rectifier device will directly become a wire, forming a short circuit and making it unusable; another situation is that even if the solder does not touch the edge of the chip, the customer In the process of use, high temperature is generated to melt the solder piece, and the above situation will also occur, resulting in increased customer losses.

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