Submerged basic island, embedded basic island lead frame structure and first-etching last-plating method thereof

Abstract

The invention relates to a submerged basic island, an embedded basic island lead frame structure and a first-etching last-plating method thereof. The structure comprises basic islands (1) and pins (2), wherein two groups of basic islands (1) are arranged, and one group is a first basic island (1.1) while the other group is a second basic island (1.2); the center region of the front side of the first basic island (1.1) is submerged; first metal layers (4) are arranged on front sides of the second basic island (1.2) and the pins (2); back sides of the first basic island (1.1) and the pins (2) are provided with second metal layers (5); molding compounds (3) without filler are embedded in the region on the periphery of the pins (2), the region between the pins (2) and the first basic island (1.1), the region between the first basic island (1.1) and the second basic island (1.2), the back side of the second basic island (1.2), the region between the second basic island (1.2) and the pins (2) and the region between the pins (2); and back sizes of the first basic island and the pins are smaller than front sizes of the first basic island and the pins to form a big-end-up first basic island and pin structures. The invention has the advantages of high restricting capacity of the molding compounds with the metal pins.

Description

(1) Technical field [0001] The invention relates to a lead frame structure of a sunken base island and an embedded type base island and a method for engraving first and then plating. It belongs to the technical field of semiconductor packaging. (2) Background technology [0002] The traditional lead frame structure is described in detail as follows: [0003] After chemical etching and surface electroplating are carried out on the front side of the metal substrate, the production of the lead frame is completed (such as Figure 14 shown). The backside of the lead frame is then etched during the packaging process. [0004] However, the above-mentioned lead frame has the following disadvantages in the packaging process: [0005] This kind of lead frame structure is half-etched on the front of the metal substrate, because half-etching is only performed on the front of the metal substrate, and the plastic encapsulant only covers the height of half a foot during the plastic enca...

AI Technical Summary

Problems solved by technology

[0005] This kind of lead frame structure is half-etched on the front of the metal substrate, because half-etching is only performed on the front of the metal substrate, and the plastic encapsulant only covers the height of half a foot during the plastic encapsulation process, so the plastic encapsulation and the metal The binding ability of the feet becomes smaller. If the plastic package is not attached to the PCB board very well, it is easy to cause the problem of foot drop (such as Figure 15 shown)

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