First-coating last-etching single package method for positively packaging double-sided graphic chip

Abstract

The invention relates to a first-coating last-etching single package method for positively packaging a double-sided graphic chip. The method comprises the following technical steps: taking a metal substrate; plating a metal layer to coat the metal substrate; carrying out backside etching on the metal substrate; enveloping plastic pacing material (epoxy resin) without filler on the backside of the metal substrate; carrying out positive etching on the metal substrate; etching the positive sides of a basic island and a pin, wherein the backside sizes of the basic island and the pin are smaller than the positive sizes of the basic island and the pin to form a basic inland and pin structure with big top and small bottom; loading pieces; routing metal wires; enveloping local units by using plastic pacing material (epoxy resin) with filler on the positive side of the semi-finished product to ensure local unit areas on the positive side of the pin to expose the plastic pacing material (epoxy resin) with filler; plating metal layers on the backsides of the island and the pin and the positive side of the pin for coating; and cutting. The package structure of the chip prepared by the method of the invention does not have the problem of falling feet, and the length of the metal wires is shortened.

Description

(1) Technical field [0001] The invention relates to a single packaging method for a double-sided graphics chip, which is first plated and then engraved. It belongs to the technical field of semiconductor packaging. (2) Background technology [0002] The traditional manufacturing method of the chip packaging structure is: 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 43 shown). The backside of the leadframe is etched during the packaging process. This law has the following shortcomings: [0003] Because only half-etching work is done on the front of the metal substrate before plastic sealing, and the plastic sealing material is only half a foot high to cover the pins during the plastic sealing process, so the binding ability between the plastic package and the pins becomes smaller. If the plastic package is considerate When the chip is not very good ...

AI Technical Summary

Problems solved by technology

[0004] In addition, due to the long distance between the chip and the pin, the length of the metal wire is long, such as Figures 45-46 As shown, the cost of metal wires is high (especially expensive pure gold metal wires); also due to the long length of metal wires, the signal output speed of the chip is slow (especially for storage products and those that require a large amount of data) calculation, more prominent); also because the length of the metal wire is longer, the interference of the parasitic resistance / capacitance and the parasitic pole existing in the metal wire to the signal is also higher; and because the chip and the pin between The longer the distance, the larger the volume and area of ​​the package, the higher the material cost, and the more waste

Images