CN103441078B - First it is honored as a queen and loses three-dimensional systematic chip formal dress stack package structure and process - Google Patents

Abstract

The invention relates to a three-dimensional system-level chip stacked package structure and process method that is sealed first and etched later. It includes a base island (1) and pins (2), and conductive pillars (3) are arranged on the front of the pins (2) , the front side of the base island (1) is equipped with a chip (4) through a conductive or non-conductive adhesive substance (6), and the front side of the chip (4) is connected to the front side of the pin (2) through a metal wire (5) connection, the area on the front of the base island (1) and the pin (2) and the area around the conductive pillar (3), the chip (4) and the metal wire (5) are encapsulated with plastic encapsulant or epoxy resin (7 ), the surface of the base island (1), pins (2) and conductive pillars (3) exposed to the molding compound or epoxy resin (7) is provided with an anti-oxidation layer (8), and the top of the conductive pillars (3) Packages (10) are stacked through the conductive substance (9). The beneficial effect of the invention is that it can solve the problem that the quality of interconnection solder balls between packages is difficult to control due to the fact that the solder pads of the bottom substrate are lower than the plastic surface of the bottom layer in traditional substrate package stacking.

Description

Seal-before-etch three-dimensional system-on-chip front-mount package structure and process method

technical field

The invention relates to a three-dimensional system-level chip front-mount stack packaging structure and a process method after sealing first and etching later, and belongs to the technical field of semiconductor packaging.

Background technique

The traditional common PoP package stacking structure is that the bottom logic device substrate package is stacked with the top layer storage device substrate package, and the bottom layer device and the top layer device are stacked and electrically interconnected by solder ball mounting and reflow soldering ( as shown in Figure 80).

The above PoP (Package on Package) packaging structure has the following disadvantages:

1. The pads connecting the bottom package and the top package are located on the substrate of the bottom package, which is lower than the plastic cover of the bottom package, so the molding height of the bottom package is limited by the size of the metal solder ball on the bottom surface of the top package and height, thereby limiting the number of layers of chip stacking inside the bottom package. Correspondingly, a single small-sized solder ball cannot be implanted in the outer pin of the top package, otherwise the solder ball height of the top package is too small to be interconnected with the pad of the bottom package (as shown in Figure 81).

2. The bottom package and the top package are interconnected through the metal solder balls on the outer legs of the top package. After reflow soldering, the metal solder balls will be thermally deformed, and the distance between the top package solder balls will be smaller than before reflow soldering, as shown in Figure 82. To avoid short circuits between solder balls, it is not possible to use a package stack with a top package of Fine Pitch (fine pitch).

3. If the substrate package is stacked to reduce the ball pitch by stacking multiple small metal tin balls for interconnection, it will be difficult to align during the mounting and stacking process, which will easily cause accuracy deviation (as shown in Figure 83) or the upper ball will slip, affecting Mounting yield

4. Substrate packages are stacked with multiple small metal solder balls for interconnection. After reflow soldering, the small metal solder balls undergo different thermal deformations, which may easily cause displacement deviation of the solder balls or even cause a short circuit.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned shortcomings, and provide a three-dimensional system-in-package structure and process method for sealing first and then etching chips, which can solve the gap between packages caused by the traditional substrate package stacking due to the bottom substrate pad being lower than the bottom plastic cover. The problem that the quality of interconnection solder balls is difficult to control.

The object of the present invention is achieved in the following way: a process method for encapsulating first and then etching a three-dimensional system-on-chip stacked package structure, said method comprising the following steps:

Step 1. Take the metal substrate

Step 2. Pre-plating copper on the surface of the metal substrate

Pre-plating a layer of copper on the surface of the metal substrate,

Step 3: Paste the photoresist film

In step 2, a photoresist film that can be exposed and developed is pasted on the front and back of the metal substrate of the pre-plated copper material;

Step 4. Remove part of the photoresist film from the front of the metal substrate

Use exposure and developing equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 3, so as to expose the area that needs to be electroplated on the metal circuit layer on the front of the metal substrate;

Step 5. Plating metal circuit layer

Electroplate a metal circuit layer in the area where part of the photoresist film is removed from the front of the metal substrate in step 4. After the electroplating of the metal circuit layer is completed, corresponding base islands and pins are formed on the front of the metal substrate;

Step 6. Paste photoresist film

In step 5, a photoresist film that can be exposed and developed is pasted on the front side of the metal substrate on which the electroplated metal circuit layer is completed;

Step 7. Remove part of the photoresist film from the front of the metal substrate

Use exposure and developing equipment to expose, develop and remove part of the patterned photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 6, so as to expose the area on the front of the metal substrate that needs to be electroplated with conductive pillars;

Step 8. Plating conductive pillars

Electroplate conductive pillars in the area where part of the photoresist film is removed from the front of the metal substrate in step 7;

Step 9. Remove the photoresist film

Remove the photoresist film on the surface of the metal substrate;

Step ten, loading film

Coating conductive or non-conductive bonding substances on the front side of the base island formed in step 5 to implant the first chip;

Step 11. Wire Bonding

Carry out bonding wire operation between the front surface of the first chip and the pins formed in step five;

Step 12. Epoxy resin plastic sealing

Epoxy resin plastic sealing protection is carried out on the front of the metal substrate after chip loading and wiring;

Step 13. Epoxy resin surface grinding

Surface grinding is carried out after completing the epoxy resin molding in step 12;

Step 14. Paste photoresist film

In step 13, a photoresist film that can be exposed and developed is pasted on the front and back of the metal substrate after the epoxy resin surface is ground;

Step 15. Remove part of the photoresist film on the back of the metal substrate

Use the exposure and development equipment to expose, develop and remove part of the graphic photoresist film on the back of the metal substrate that has been pasted with the photoresist film in step 14, so as to expose the area that needs to be etched later on the back of the metal substrate;

Step 16. Etching

Perform chemical etching in the region where part of the photoresist film is removed on the back of the metal substrate in step fifteen;

Step seventeen, remove the photoresist film

Remove the photoresist film on the surface of the metal substrate;

Step 18. Cover the back of the metal substrate with green paint or photosensitive non-conductive adhesive

Apply green paint or photosensitive non-conductive adhesive to the back of the metal substrate after removing the photoresist film in step seventeen;

Step 19: Exposure, window development

Use exposure and development equipment to expose and develop the green paint or photosensitive non-conductive adhesive on the back of the metal substrate to expose the area on the back of the metal substrate that needs to be electroplated with a high-conductivity metal layer;

Step 20: Plating a highly conductive metal layer

Electroplate a highly conductive metal layer in the window area of the green paint on the back of the metal substrate or photosensitive non-conductive adhesive in step 19;

Step 21: Plating anti-oxidation metal layer or coating anti-oxidant (OSP)

Anti-oxidation metal layer electroplating or anti-oxidant coating (OSP) on the exposed metal surface of the metal substrate;

Step 22. Stack Packages

In step 21, the electroplating anti-oxidation metal layer or the top of the conductive pillar covered with anti-oxidant is carried out to stack the packages;

Step 23. Cut the finished product

The semi-finished product stacked in step 20 is cut and cut, so that the plastic package modules that are originally integrated in the form of an array assembly and contain chips are cut and separated one by one, and the three-dimensional system level of sealing first and etching later is obtained. The chip is mounted on a stacked package structure.

A process method for encapsulating first and then etching a three-dimensional system-on-a-chip stacked packaging structure, the method comprising the following steps:

Step 1. Take the metal substrate

Step 2. Pre-plating copper on the surface of the metal substrate

Pre-plating a layer of copper on the surface of the metal substrate;

Step 3: Paste the photoresist film

In step 2, a photoresist film that can be exposed and developed is pasted on the front and back of the metal substrate of the pre-plated copper material;

Step 4. Remove part of the photoresist film from the front of the metal substrate

Using exposure and development equipment, the front of the metal substrate that has completed the photoresist film pasting operation in step 3 is subjected to pattern exposure, development and removal of part of the pattern photoresist film, so as to expose the area on the front of the metal substrate that needs to be electroplated for the first metal circuit layer;

Step 5. Electroplating the first metal circuit layer

Electroplating the first metal circuit layer in the area where part of the photoresist film is removed from the front of the metal substrate in step 4;

Step 6. Paste photoresist film

In step 5, a photoresist film that can be exposed and developed is pasted on the front side of the metal substrate that has electroplated the first metal circuit layer;

Step 7. Remove part of the photoresist film from the front of the metal substrate

Use exposure and development equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 6, so as to expose the area that needs to be electroplated on the second metal circuit layer on the front of the metal substrate;

Step 8. Electroplating the second metal circuit layer

Electroplating the second metal circuit layer in the area where part of the photoresist film is removed on the front side of the metal substrate in step 7 as a conductive pillar for connecting the first metal circuit layer and the third metal circuit layer;

Step 9. Remove the photoresist film

Remove the photoresist film on the surface of the metal substrate;

Step 10. Paste and press the non-conductive film

Paste a layer of non-conductive adhesive film on the front of the metal substrate;

Step 11. Grinding the surface of the non-conductive film

Surface grinding is carried out after the non-conductive adhesive film is pasted and pressed in step ten;

Step 12. Metallization pretreatment on the surface of the non-conductive film

Carry out metallization pretreatment on the surface of the non-conductive adhesive film, so that the surface is attached with a layer of metallized polymer material or surface roughening treatment;

Step 13. Paste photoresist film

Paste a photoresist film that can be exposed and developed on the front and back of the metallized metal substrate in step 12;

Step 14. Remove part of the photoresist film from the front of the metal substrate

Exposing, developing and removing part of the graphic photoresist film on the front of the metal substrate on which the photoresist film pasting operation has been completed in step 13 by using exposure and development equipment, so as to expose the pattern of the area on the front of the metal substrate that needs to be etched later;

Step 15. Etching

Etching the area after opening the photoresist film on the front of the metal substrate in step 14;

Step sixteen, remove the photoresist film

Remove the photoresist film on the front of the metal substrate;

Step seventeen, electroplating the third metal circuit layer

In step 15, the metallized pretreatment area retained after etching on the front side of the metal substrate is electroplated with a third metal circuit layer, and after the electroplating of the third metal circuit layer is completed, corresponding base islands and pins are formed on the front side of the metal substrate;

Step 18. Paste photoresist film

In step 17, a photoresist film that can be exposed and developed is pasted on the front side of the metal substrate on which the electroplating of the third metal circuit layer is completed;

Step 19. Remove part of the photoresist film from the front of the metal substrate

Using the exposure and development equipment, perform graphic exposure, development and removal of part of the graphic photoresist film on the front of the metal substrate after step 18 has completed the operation of pasting the photoresist film, so as to expose the area on the front of the metal substrate that needs to be electroplated with conductive pillars;

Step 20: Plating conductive pillars

Electroplate conductive pillars in the area where part of the photoresist film is removed from the front of the metal substrate in step 19;

Step 21. Remove the photoresist film

Remove the photoresist film on the surface of the metal substrate;

Step 22, loading film

Coating conductive or non-conductive adhesive substance on the front side of the base island formed in step 17 to implant the first chip;

Step 23. Metal wire bonding

Carry out bonding wire operation between the front surface of the first chip and the pins formed in step five;

Step 24: Epoxy resin molding

Epoxy resin plastic sealing protection is carried out on the front of the metal substrate after chip loading and wiring;

Step 25. Epoxy resin surface grinding

Surface grinding is carried out after epoxy resin molding is completed in step 24;

Step 26. Paste the photoresist film

Paste a photoresist film that can be exposed and developed on the front and back of the metal substrate after the epoxy resin surface is ground in step 25;

Step 27. Remove part of the photoresist film on the back of the metal substrate

Use the exposure and development equipment to expose, develop and remove part of the graphic photoresist film on the back of the metal substrate after the photoresist film pasting operation in step 26, so as to expose the area that needs to be etched on the back of the metal substrate;

Step 28. Etching

Perform chemical etching in the area where part of the photoresist film is removed on the back of the metal substrate in step 27;

Step 29. Remove the photoresist film

Remove the photoresist film on the surface of the metal substrate;

Step 30. Cover the back of the metal substrate with green paint or photosensitive non-conductive adhesive

After removing the photoresist film in step 29, coat the back of the metal substrate with green paint or photosensitive non-conductive adhesive;

Step 31: Exposure, window development

Use exposure and development equipment to expose and develop the green paint or photosensitive non-conductive adhesive on the back of the metal substrate to expose the area on the back of the metal substrate that needs to be electroplated with a high-conductivity metal layer;

Step thirty-two, electroplating a highly conductive metal layer

Electroplate a highly conductive metal layer in the window area of the green paint on the back of the metal substrate or photosensitive non-conductive adhesive in step 31;

Step 33: Plating anti-oxidation metal layer or coating anti-oxidant (OSP)

Plating an anti-oxidation metal layer or coating an anti-oxidant (OSP) on the exposed metal surface of the metal substrate;

Step 34. Stack Packages

In step 33, the anti-oxidation metal layer is electroplated or the anti-oxidant is coated on the back of the pin to stack the package body;

Step 35. Cut the finished product

The semi-finished product stacked in step 33 is cut and cut, so that the plastic package modules that are originally integrated in the form of an array assembly and contain chips are cut and separated one by one, and the three-dimensional system level that is sealed first and etched later is obtained. The chip is mounted on a stacked package structure.

The steps six to seventeen are repeated multiple times between steps five and eighteen.

A three-dimensional system-level chip stacked packaging structure that is sealed first and etched later. It includes a base island and pins. The front side of the pins is provided with conductive pillars, and the front side of the base island is positively loaded with chips through conductive or non-conductive adhesive materials. The front of the chip and the front of the pins are connected by metal wires, and the base island and the front of the pins, as well as the conductive pillars, the peripheral areas of the chip and the metal wires are all encapsulated with a plastic encapsulant or epoxy resin, and the plastic encapsulant Or the epoxy resin is flush with the top of the conductive pillar, the base island and the back of the pin are provided with a highly conductive metal layer, and the space between the highly conductive metal layer and the high conductive metal layer is filled with green paint or photosensitive non-conductive adhesive An anti-oxidation layer is provided on the surface of the conductive pillar exposed from the molding compound or epoxy resin and the surface of the highly conductive metal layer exposed from the green paint or photosensitive non-conductive adhesive material, and the package is stacked on the top of the conductive pillar through the conductive substance.

The outer pins of the package body are L-shaped pins, J-shaped pins, flat pins or metal balls.

The package is stacked on top of the conductive pillars, and the package is formed by stacking a single or multiple lead frame structures and package structures.

A metal ball is arranged on the top of the conductive pillar.

The package can be stacked on top of the conductive pillars, or on the highly conductive metal layer on the back of the pins.

Compared with the prior art, the present invention has the following beneficial effects:

Compared with the prior art, the present invention has the following beneficial effects:

1. The present invention stacks the package body by embedding the three-dimensional metal circuit composite substrate of the object, and the interlayer of the three-dimensional metal circuit composite substrate itself can be embedded in the object, so the three-dimensional system-level metal circuit substrate can directly stack the package body to realize PoP ( package-on-package) system-level functional integration package;

2. The three-dimensional system-level metal circuit composite substrate and the package are interconnected through conductive pillars on the substrate or RDL (redistribution) circuit nodes. The conductive pillars or RDL (redistribution) circuit nodes are all exposed on the surface of the plastic package of the substrate, so there is no need to plant metal balls between the three-dimensional system-level metal circuit substrate and the top-level package, and devices in any package form can be directly and flexibly stacked, including passive components such as Resistors, capacitors, inductors, etc.;

3. The conductive pillars or RDL (rewiring) circuit nodes of the three-dimensional system-level metal circuit substrate are exposed on the surface of the substrate plastic package, so the thickness of the substrate will not be limited by the height of the interconnection nodes, and the interior of the substrate can be stacked and embedded with multi-layer chips as needed or passive components;

4. The conductive pillars or (rewiring) circuit nodes of the three-dimensional system-level metal circuit substrate are exposed on the plastic surface of the substrate, so the outer pins of the top package can be interconnected with the conductive pillars by using small metal balls, as shown in Figure 84.

5. The three-dimensional system-level metal circuit substrate and the package are interconnected through the conductive pillars on the substrate, so the conductive pillars will not undergo thermal deformation before and after reflow soldering, so there is no need to add conductive pillars to avoid short circuit between the conductive pillars after reflow soldering The spacing between them is convenient for stacking fine-pitch packages.

Description of drawings

1 to 23 are schematic diagrams of each process in Embodiment 1 of a process method for a three-dimensional system-on-a-chip front-loaded stack package structure according to the present invention.

FIG. 24 is a schematic diagram of Embodiment 1 of a three-dimensional system-on-a-chip front-load stack package structure according to the present invention.

25 to 71 are schematic diagrams of each process in Embodiment 2 of a process method of a three-dimensional system-on-a-chip front-load stack package structure according to the present invention.

FIG. 72 is a schematic diagram of Embodiment 2 of a package-first-etch-later three-dimensional system-on-a-chip front-pack package structure according to the present invention.

FIG. 73 is a schematic diagram of Embodiment 3 of a three-dimensional system-on-a-chip front-pack package structure according to the present invention.

FIG. 74 is a schematic diagram of Embodiment 4 of a package-first-etch-later three-dimensional system-on-a-chip front-pack package structure according to the present invention.

FIG. 75 is a schematic diagram of Embodiment 5 of a package-first-etch-then-three-dimensional system-on-a-chip front-pack package structure according to the present invention.

FIG. 76 is a schematic diagram of Embodiment 6 of a package-first-etch-then-three-dimensional system-on-a-chip front-pack package structure according to the present invention.

FIG. 77 is a schematic diagram of Embodiment 7 of a package-first-etch-later three-dimensional system-on-a-chip front-pack package structure according to the present invention.

FIG. 78 is a schematic diagram of Embodiment 8 of a package-first-etch-later three-dimensional system-on-a-chip front-pack package structure according to the present invention.

Fig. 79 is a schematic diagram of Embodiment 9 of a front-pack package structure of a three-dimensional system-on-a-chip stacked before etching according to the present invention.

FIG. 80 is a schematic diagram of a conventional PoP substrate package stack structure.

FIG. 81 is a schematic diagram of a traditional PoP substrate package stacking structure in which the solder ball height of the top package is too small to be interconnected with the pads of the bottom package.

FIG. 82 is a schematic diagram of a traditional PoP substrate package stacking structure in which solder balls are thermally deformed after reflow soldering and cannot achieve fine-pitch package stacking.

FIG. 83 is a schematic diagram of stacking and offsetting multiple small metal solder balls.

FIG. 84 is a schematic diagram showing that the outer pins of the top package of the present invention can be interconnected with a three-dimensional system-level metal circuit substrate by using small metal balls.

in:

base island 1

pin 2

Conductive pillar 3

chip 4

Metal wire 5

Conductive or non-conductive bonding substances6

Molding Compound or Epoxy 7

Antioxidant layer 8

Conductive substance 9

Package 10

Lead frame structure 10.1

Package Structure 10.2

Highly Conductive Metal Layer 11

Green paint or photosensitive non-conductive adhesive 12

metal ball13.

detailed description

The structure and process method of a three-dimensional system-level chip stacked packaging structure and process are as follows:

Example 1: Single-layer circuit

Referring to Fig. 24, the present invention presents a three-dimensional system-on-a-chip stacked packaging structure, which includes a base island 1 and pins 2. Conductive pillars 3 are arranged on the front side of the pins 2, and the front side of the base island 1 passes through Conductive or non-conductive bonding substance 6 is equipped with chip 4, the front of said chip 4 is connected with the front of pin 2 through metal wire 5, the front area of said base island 1 and pin 2 and conductive pillar 3, chip 4 and the peripheral area of the metal wire 5 are encapsulated with a molding compound or epoxy resin 7, the molding compound or epoxy resin 7 is flush with the top of the conductive pillar 3, and the back of the base island 1 and the pin 2 is provided with a highly conductive metal Layer 11, green paint or photosensitive non-conductive adhesive material 12 is filled between the highly conductive metal layer 11 and the highly conductive metal layer 11, and the conductive pillar 3 exposes the surface of the molding compound or epoxy resin 7 and the highly conductive metal An anti-oxidation layer 8 is provided on the surface of the layer 11 that exposes the green paint or photosensitive non-conductive adhesive material 12. The top of the conductive pillar 3 is stacked with a package 10 through a conductive material 9. The outer legs of the package 10 are L-shaped legs. .

Its process method is as follows:

Step 1. Take the metal substrate

See Figure 1, take a piece of metal substrate with appropriate thickness, the material of metal substrate can be copper, iron, galvanized material, stainless steel or aluminum or metal material that can achieve conductive function, etc. The choice of thickness can be based on product characteristics make a choice;

Step 2. Pre-plating copper on the surface of the metal substrate

Referring to Figure 2, a layer of copper is pre-plated on the surface of the metal substrate. The thickness of the copper layer is 2 to 10 microns. It can also be thinned or thickened according to the functional requirements. The electroplating method can be electrolytic plating or chemical deposition;

Step 3: Paste the photoresist film

Referring to Figure 3, in step 2, the front and back of the metal substrate of the pre-plated copper material are respectively pasted with a photoresist film that can be exposed and developed. The purpose is to make subsequent metal circuit patterns. The photoresist film can be a dry photoresist film It can also be a wet photoresist film;

Step 4. Remove part of the photoresist film from the front of the metal substrate

Referring to Figure 4, use the exposure and developing equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 3, so as to expose the area on the front of the metal substrate that needs to be electroplated with the metal circuit layer;

Step 5. Plating metal circuit layer

Referring to Figure 5, a metal circuit layer is electroplated in the area where part of the photoresist film is removed from the front of the metal substrate in step 4. After the metal circuit layer is electroplated, corresponding base islands and pins are formed on the front of the metal substrate. The material of the metal circuit layer It can be copper, aluminum, nickel, silver, gold, copper silver, nickel gold or nickel palladium gold or metal substances that can achieve conductive function, etc. The thickness of the metal circuit layer is 5~20 microns, and different plating materials can be selected according to different applications According to different characteristics, the thickness of electroplating can be changed, and the electroplating method can be electrolytic plating or chemical deposition;

Step 6. Paste photoresist film

Referring to Figure 6, the photoresist film that can be exposed and developed is pasted on the front of the metal substrate where the electroplated metal circuit layer is completed in step 5. The purpose is to make the subsequent conductive pillars. The photoresist film can be a dry photoresist film or a wet photoresist film. Photoresist film;

Step 7. Remove part of the photoresist film from the front of the metal substrate

Referring to Figure 7, use the exposure and developing equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 6, so as to expose the area on the front of the metal substrate that needs to be electroplated with conductive pillars;

Step 8. Plating conductive pillars

Referring to Figure 8, electroplate conductive pillars in the area where part of the photoresist film is removed from the front of the metal substrate in step 7. The material of the conductive pillars can be copper, aluminum, nickel, silver, gold, copper silver, nickel gold, nickel palladium gold or For materials such as metal substances that can achieve conductive functions, the electroplating method can be electrolytic plating or chemical deposition;

Step 9. Remove the photoresist film

Referring to Figure 9, remove the photoresist film on the surface of the metal substrate. The method of removing the photoresist film is softened by chemical potion and rinsed with high-pressure water;

Step ten, loading film

Referring to FIG. 10 , the front side of the base island formed in step five is coated with a conductive or non-conductive adhesive substance to implant the first chip;

Step 11. Wire Bonding

Referring to FIG. 11 , the metal wire bonding operation is performed between the front surface of the first chip and the pins formed in step 5;

Step 12. Epoxy resin plastic sealing

Referring to Figure 12, epoxy resin is used to protect the front of the metal substrate after chip loading and wiring. The epoxy resin material can be filled or not filled according to product characteristics;

Step 13. Epoxy resin surface grinding

Referring to Figure 13, surface grinding is performed after epoxy resin molding is completed in step 12;

Step 14. Paste photoresist film

Referring to FIG. 14 , in step 13, the front and back of the metal substrate after the surface grinding of the epoxy resin is pasted with a photoresist film that can be exposed and developed;

Step 15. Remove part of the photoresist film on the back of the metal substrate

Referring to FIG. 15 , use the exposure and developing equipment to expose, develop and remove part of the graphic photoresist film on the back of the metal substrate that has completed the photoresist film pasting operation in step 14, so as to expose the area that needs to be etched later on the back of the metal substrate;

Step 16. Etching

Referring to Fig. 16, chemical etching is carried out in the area where part of the photoresist film is removed on the back of the metal substrate in step 15, and the etching method can be copper chloride or ferric chloride;

Step seventeen, remove the photoresist film

Referring to Figure 17, remove the photoresist film on the surface of the metal substrate. The method of removing the photoresist film is softened by chemical potion and rinsed with high-pressure water;

Step 18. Cover the back of the metal substrate with green paint or photosensitive non-conductive adhesive

Referring to Fig. 18, the back of the metal substrate after removing the photoresist film in step 17 is coated with green paint or photosensitive non-conductive adhesive;

Step 19: Exposure, window development

Referring to Figure 19, use the exposure and development equipment to expose and develop the green paint or photosensitive non-conductive adhesive material coated on the back of the metal substrate to expose the area on the back of the metal substrate that needs to be electroplated with a high-conductivity metal layer;

Step 20: Plating a highly conductive metal layer

Referring to Figure 20, in step 19, electroplate a highly conductive metal layer in the window area of the green paint on the back of the metal substrate or photosensitive non-conductive adhesive material, the electroplating method can be electrolytic plating or chemical deposition;

Step 21: Plating anti-oxidation metal layer or coating anti-oxidant (OSP)

Referring to Figure 21, electroplating an anti-oxidation metal layer on the exposed metal surface of the metal substrate, such as gold, nickel gold, nickel palladium gold, tin or coated antioxidant (OSP);

Step 22. Stack Packages

Referring to FIG. 22 , in step 21, the electroplating anti-oxidation metal layer or the top of the conductive pillar coated with anti-oxidant is stacked with a conductive substance;

Step 23. Cut the finished product

Referring to Figure 23, the semi-finished product stacked in step 20 is cut, so that the plastic package modules that are originally integrated in the form of an array assembly and contain chips are cut and separated one by one, and the first-sealed and later-packed The three-dimensional system-on-a-chip stacked package structure is finished.

Embodiment 2: multi-layer circuit

Referring to Fig. 72, the present invention presents a three-dimensional system-on-a-chip stacked package structure, which includes a base island 1 and pins 2, and conductive pillars 3 are arranged on the front side of the pins 2, and the front side of the base island 1 passes through Conductive or non-conductive bonding material 6 is equipped with chip 4, the front of said chip 4 is connected with the front of pin 2 through metal wire 5, the area of said base island 1 and the front of pin 2 and conductive pillar 3, chip 4 and the peripheral area of the metal wire 5 are encapsulated with molding compound or epoxy resin 7, the molding compound or epoxy resin 7 is flush with the top of the conductive pillar 3, and the base island 1 and the back of the pin 2 are provided with high The conductive metal layer 11 is filled with green paint or photosensitive non-conductive adhesive material 12 between the high conductive metal layer 11 and the high conductive metal layer 11, and the conductive pillar 3 exposes the surface of the molding compound or epoxy resin 7 and the high The conductive metal layer 11 exposes the green paint or the surface of the photosensitive non-conductive adhesive material 12 is provided with an anti-oxidation layer 8, and the top of the conductive pillar 3 is stacked with a package body 10 through a conductive material 9, and the outer leg of the package body 10 is L shaped feet.

The difference between embodiment 2 and embodiment 1 is that: both the base island 1 and the pin 2 are composed of multiple layers of metal circuit layers, and the metal circuit layers are connected by conductive pillars.

Its process method is as follows:

Step 1. Take the metal substrate

Referring to Figure 25, take a piece of metal substrate with a suitable thickness. The material of the metal substrate can be copper, iron, galvanized, stainless steel, aluminum or metal or non-metal that can achieve conductive function. The thickness can be selected Choose according to product characteristics;

Step 2. Pre-plating copper on the surface of the metal substrate

Referring to Figure 26, a layer of copper is pre-plated on the surface of the metal substrate. The thickness of the copper layer is 2 to 10 microns. It can also be thinned or thickened according to functional requirements. The electroplating method can be electrolytic plating or chemical deposition;

Step 3: Paste the photoresist film

Referring to Figure 27, in step 2, the front and back of the metal substrate of the pre-plated copper material are respectively pasted with a photoresist film that can be exposed and developed. The purpose is to make subsequent metal circuit patterns. The photoresist film can be a dry photoresist film It can also be a wet photoresist film;

Step 4. Remove part of the photoresist film from the front of the metal substrate

Referring to Figure 28, use the exposure and development equipment to expose, develop and remove part of the patterned photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 3, so as to expose the area that needs to be electroplated on the first metal circuit layer on the front of the metal substrate ;

Step 5. Electroplating the first metal circuit layer

Referring to Figure 29, the first metal circuit layer is electroplated in the area where part of the photoresist film is removed from the front of the metal substrate in step 4. The material of the first metal circuit layer can be copper, aluminum, nickel, silver, gold, copper silver, nickel Gold or nickel-palladium-gold, etc., the electroplating method can be electrolytic plating or chemical deposition;

Step 6. Paste photoresist film

Referring to Figure 30, in Step 5, the metal substrate that has electroplated the first metal circuit layer is pasted with a photoresist film that can be exposed and developed for the purpose of making subsequent metal circuit patterns. The photoresist film can be dry photoresist film or Can be a wet photoresist film;

Step 7. Remove part of the photoresist film from the front of the metal substrate

Referring to Figure 31, use the exposure and developing equipment to expose, develop and remove part of the patterned photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 6, so as to expose the area on the front of the metal substrate that needs to be electroplated for the second metal circuit layer ;

Step 8. Electroplating the second metal circuit layer

Referring to Fig. 32, in the area where part of the photoresist film is removed from the front of the metal substrate in step 7, the second metal wiring layer is electroplated as a conductive pillar for connecting the first metal wiring layer and the third metal wiring layer, and the second metal wiring layer The material can be copper, aluminum, nickel, silver, gold, copper silver, nickel gold, nickel palladium gold or metal substances that can achieve conductive functions, and the electroplating method can be electrolytic plating or chemical deposition;

Step 9. Remove the photoresist film

Referring to Figure 33, remove the photoresist film on the surface of the metal substrate. The method of removing the photoresist film is softened by chemical potion and rinsed with high-pressure water;

Step 10. Paste and press the non-conductive film

Referring to Figure 34, a layer of non-conductive adhesive film is pasted on the front of the metal substrate (the area with the circuit layer), the purpose of which is to insulate the first metal circuit layer from the third metal circuit layer; the way of pasting the non-conductive film Conventional rolling equipment can be used, or it can be pasted in a vacuum environment to prevent air residue during the pasting process; the non-conductive adhesive film is mainly pasted and pressed thermosetting epoxy resin, and epoxy resin can According to the characteristics of the product, non-conductive film with no filler or filler is used;

Step 11. Grinding the surface of the non-conductive film

Referring to Figure 35, surface grinding is carried out after the non-conductive adhesive film is pasted and pressed in step 10. The purpose is to expose the second metal circuit layer, maintain the flatness of the non-conductive adhesive film and the second metal circuit layer, and control the thickness of the non-conductive adhesive film ;

Step 12. Metallization pretreatment on the surface of the non-conductive film

Referring to Figure 36, metallization pretreatment is carried out on the surface of the non-conductive adhesive film, so that the surface is attached with a layer of metallized polymer material or the surface is roughened. Polymer materials can be dried by spraying, plasma shock, surface roughening, etc.;

Step 13. Paste photoresist film

Referring to Figure 37, in step 12, a photoresist film that can be exposed and developed is attached to the front and back of the metal substrate that has been metallized. The purpose is to make subsequent metal circuit patterns. The photoresist film can be a dry photoresist film It is a wet photoresist film;

Step 14. Remove part of the photoresist film from the front of the metal substrate

Referring to FIG. 38 , use the exposure and developing equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 13, so as to expose the area pattern that needs to be etched later on the front of the metal substrate;

Step 15. Etching

Referring to Fig. 39, the etching operation is carried out on the area after the window opening of the photoresist film on the front side of the metal substrate in step 14. The purpose is to use etching technology to etch and remove the subsequent metallization pretreatment area that does not need to be electroplated with the third metal circuit layer. The etching method can be copper chloride or ferric chloride process;

Step sixteen, remove the photoresist film

Referring to Figure 40, remove the photoresist film on the front of the metal substrate. The method of removing the photoresist film is softened by chemical potion and rinsed with high-pressure water;

Step seventeen, electroplating the third metal circuit layer

Referring to Fig. 41, in step 15, the metallized pretreatment area remaining after the front of the metal substrate is etched is electroplated with a third metal circuit layer, and the material of the third metal circuit layer can be copper, aluminum, nickel, silver, gold, copper Silver, nickel gold or nickel palladium gold, etc., the electroplating method can be electrolytic plating or chemical deposition;

Step 18. Paste photoresist film

Referring to Figure 42, in step 18, a photoresist film that can be exposed and developed is pasted on the front side of the metal substrate that is electroplated with the third metal circuit layer. The purpose is to make subsequent metal circuit patterns. The photoresist film can be a dry photoresist film It can also be a wet photoresist film;

Step 19. Remove part of the photoresist film from the front of the metal substrate

Referring to Figure 43, use the exposure and developing equipment to expose, develop and remove part of the patterned photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 18, so as to expose the surface of the metal substrate that needs to be subsequently electroplated on the fourth metal circuit layer area;

Step 20, electroplating the fourth metal circuit layer

Referring to Fig. 44, in the area where part of the photoresist film is removed from the front of the metal substrate in step nineteen, the fourth metal circuit layer is electroplated as a conductive pillar for connecting the third metal circuit layer and the fifth metal circuit layer, and the fourth metal circuit layer The material of the layer can be copper, aluminum, nickel, silver, gold, copper silver, nickel gold, nickel palladium gold or metal substances that can achieve conductive functions, and the electroplating method can be electrolytic plating or chemical deposition;

Step 21. Remove the photoresist film

Referring to Figure 45, remove the photoresist film on the front of the metal substrate. The method of removing the photoresist film is softened by chemical potion and washed with high-pressure water;

Step 22. Paste and press the non-conductive film

Referring to Figure 46, a layer of non-conductive adhesive film is pasted on the front of the metal substrate (the area with the circuit layer), the purpose of which is to insulate the third metal circuit layer and the fifth metal circuit layer; the way of pasting and pressing the non-conductive film Conventional rolling equipment can be used, or it can be pasted in a vacuum environment to prevent air residue during the pasting process; the non-conductive adhesive film is mainly pasted and pressed thermosetting epoxy resin, and epoxy resin can According to the characteristics of the product, non-conductive film with no filler or filler is used;

Step 23. Grinding the surface of the non-conductive film

Referring to Figure 47, surface grinding is carried out after the non-conductive adhesive film is pasted and pressed in step 22. The purpose is to expose the fourth metal circuit layer, maintain the flatness of the non-conductive adhesive film and the fourth metal circuit layer, and control the non-conductive adhesive film. thickness of;

Step 24. Metallization pretreatment on the surface of the non-conductive film

Referring to Figure 48, the metallization pretreatment is carried out on the surface of the non-conductive adhesive film, so that the surface is attached with a layer of metallized polymer material or surface roughening treatment. Polymer materials can be dried by spraying, plasma shock, surface roughening, etc.;

Step 25. Paste the photoresist film

Referring to Figure 49, the front and back sides of the metallized metal substrate completed in step 24 are pasted with a photoresist film that can be exposed and developed for the purpose of making subsequent metal circuit patterns. The photoresist film can be dry photoresist film or Can be a wet photoresist film;

Step 26. Remove part of the photoresist film from the front of the metal substrate

Referring to FIG. 50 , use the exposure and developing equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 25, so as to expose the area pattern that needs to be etched later on the front of the metal substrate;

Step 27. Etching

Referring to Figure 51, the etching operation is carried out on the area after the window opening of the photoresist film on the front of the metal substrate in step 26, the purpose of which is to use etching technology to etch and remove the subsequent metallization pretreatment area that does not need to be electroplated with the fifth metal circuit layer , the etching method can be copper chloride or ferric chloride process;

Step 28, remove the photoresist film

Referring to Figure 52, remove the photoresist film on the surface of the metal substrate. The method of removing the photoresist film is softened by chemical potion and rinsed with high-pressure water;

Step 29, electroplating the fifth metal circuit layer

Referring to Fig. 53, in step 27, the metallized pretreatment area remaining after etching the front side of the metal substrate is electroplated with the fifth metal circuit layer. After the electroplating of the fifth metal circuit layer is completed, the corresponding base island and The pin, the material of the fifth metal circuit layer can be copper, aluminum, nickel, silver, gold, copper silver, nickel gold or nickel palladium gold, etc., and the electroplating method can be electrolytic plating or chemical deposition;

Step 30: Paste the photoresist film

Referring to Fig. 54, in step 29, the metal substrate on which the fifth metal circuit layer is electroplated is pasted with a photoresist film that can be exposed and developed for the purpose of making subsequent conductive pillars. The photoresist film can be a dry photoresist film It can also be a wet photoresist film;

Step 31. Remove part of the photoresist film from the front of the metal substrate

Referring to FIG. 55 , use the exposure and development equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 30, so as to expose the area on the front of the metal substrate that needs to be electroplated with conductive pillars;

Step 32. Plating conductive pillars

Referring to Figure 56, electroplate conductive pillars in the area where part of the photoresist film is removed from the front of the metal substrate in step 31. The material of the conductive pillars can be copper, aluminum, nickel, silver, gold, copper silver, nickel gold, nickel palladium For materials such as gold or metal substances that can achieve conductive functions, the electroplating method can be electrolytic plating or chemical deposition;

Step 33. Remove the photoresist film

Referring to Figure 57, remove the photoresist film on the surface of the metal substrate. The method of removing the photoresist film is softened by chemical potion and rinsed with high-pressure water;

Step thirty-four, loading film

Referring to FIG. 58, the front surface of the base island formed in step 29 is coated with a conductive or non-conductive adhesive substance to implant the first chip;

Step 35. Metal wire bonding

Referring to FIG. 59, perform bonding metal wire operation between the front surface of the first chip and the pins formed in step five;

Step 36: Epoxy resin molding

Referring to Figure 60, the front of the metal substrate after chip mounting and wire bonding is protected by epoxy resin molding. The epoxy resin material can be selected with or without filler according to product characteristics;

Step thirty-seven, epoxy resin surface grinding

Referring to FIG. 61 , perform surface grinding after epoxy resin molding is completed in step 36;

Step 38. Paste photoresist film

Referring to FIG. 62 , in step 37, the front and back of the metal substrate after the surface grinding of the epoxy resin is pasted with a photoresist film that can be exposed and developed;

Step 39. Remove part of the photoresist film on the back of the metal substrate

Referring to FIG. 63 , use the exposure and development equipment to expose, develop and remove part of the graphic photoresist film on the back of the metal substrate that has completed the photoresist film pasting operation in step 38, so as to expose the area that needs to be etched later on the back of the metal substrate;

Step 40: Etching

Referring to FIG. 64 , chemical etching is performed on the area where part of the photoresist film is removed on the back of the metal substrate in step 39, and the etching method can be copper chloride or ferric chloride;

Step 41. Remove the photoresist film

Referring to Figure 65, remove the photoresist film on the surface of the metal substrate. The method of removing the photoresist film is softened by chemical potion and rinsed with high-pressure water;

Step 42. Cover the back of the metal substrate with green paint or photosensitive non-conductive adhesive

Referring to FIG. 66 , the back of the metal substrate after removing the photoresist film in step 41 is coated with green paint or photosensitive non-conductive adhesive;

Step 43: Exposure, window development

Referring to Figure 67, use exposure and development equipment to expose and develop the green paint or photosensitive non-conductive adhesive material coated on the back of the metal substrate to expose the area on the back of the metal substrate that needs to be electroplated with a high-conductivity metal layer;

Step 44: Plating a highly conductive metal layer

Referring to Figure 68, in step 43, electroplate a highly conductive metal layer in the window area of the green paint on the back of the metal substrate or photosensitive non-conductive adhesive material, the electroplating method can be electrolytic plating or chemical deposition;

Step forty-five, electroplating anti-oxidation metal layer or coating anti-oxidant (OSP)

Referring to Figure 69, an anti-oxidation metal layer is electroplated on the exposed metal surface of the metal substrate, such as gold, nickel gold, nickel palladium gold, tin or coated antioxidant (OSP);

Step 46. Stack Packages

Referring to FIG. 70 , in step 45, the electroplating anti-oxidation metal layer or the top of the conductive pillar covered with anti-oxidant is stacked with a conductive substance;

Step forty-seven, cut the finished product

Referring to Figure 71, the semi-finished product stacked in step 43 is cut, so that the plastic package modules that are originally integrated in the form of an array assembly and contain chips are cut and separated one by one, and the first-sealed and later-packed The three-dimensional system-on-a-chip stacked package structure is finished.

Example 3: Single-layer circuit + backside stacked L-shaped package with pins

Referring to FIG. 73 , the difference between Embodiment 3 and Embodiment 1 is that the package body 10 is stacked on the anti-oxidation layer on the back of the pin.

Embodiment 4: Single-layer circuit + J-shaped pin package

Referring to FIG. 74 , the difference between Embodiment 4 and Embodiment 1 is that the outer legs of the package body 10 are J-shaped legs.

Embodiment 5: Single-layer circuit + flat-pin package

Referring to FIG. 75 , the difference between Embodiment 5 and Embodiment 1 is that the outer legs of the package body 10 are flat legs.

Example 6: Single-layer circuit + ball grid package

Referring to FIG. 76 , the difference between Embodiment 6 and Embodiment 1 is that the outer legs of the package body 10 are metal balls.

Example 7: Single-layer circuit bump packaging (1)

Referring to FIG. 77 , the difference between Embodiment 7 and Embodiment 3 is that: a metal ball 13 is arranged on the top of the conductive pillar 3 .

Example 8: Single-layer circuit bump packaging (2)

Referring to FIG. 78 , the difference between Embodiment 8 and Embodiment 1 is that metal balls 13 are provided on the back of the base island 1 and pins 2 .

Embodiment 9: Multi-layer lead frame stacked package

Referring to FIG. 79 , the difference between Embodiment 9 and Embodiment 1 is that the package 10 is mounted on the top of the conductive pillar 3, and the package 10 is formed by stacking a single or multiple lead frame structures 10.1 and package structures 10.2.

Claims (3)

1. A method for encapsulating and then etching a three-dimensional system-on-a-chip stacked packaging structure, characterized in that the method comprises the following steps: Step 1. Take the metal substrate Step 2. Pre-plating copper on the surface of the metal substrate Pre-plating a layer of copper on the surface of the metal substrate, Step 3: Paste the photoresist film In step 2, a photoresist film that can be exposed and developed is pasted on the front and back of the metal substrate of the pre-plated copper material; Step 4. Remove part of the photoresist film from the front of the metal substrate Use exposure and developing equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 3, so as to expose the area that needs to be electroplated on the metal circuit layer on the front of the metal substrate; Step 5. Plating metal circuit layer Electroplate a metal circuit layer in the area where part of the photoresist film is removed from the front of the metal substrate in step 4. After the electroplating of the metal circuit layer is completed, corresponding base islands and pins are formed on the front of the metal substrate; Step 6. Paste photoresist film In step 5, a photoresist film that can be exposed and developed is pasted on the front side of the metal substrate on which the electroplated metal circuit layer is completed; Step 7. Remove part of the photoresist film from the front of the metal substrate Use exposure and developing equipment to expose, develop and remove part of the patterned photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 6, so as to expose the area on the front of the metal substrate that needs to be electroplated with conductive pillars; Step 8. Plating conductive pillars Electroplate conductive pillars in the area where part of the photoresist film is removed from the front of the metal substrate in step 7; Step 9. Remove the photoresist film Remove the photoresist film on the surface of the metal substrate; Step ten, loading film Coating conductive or non-conductive bonding substances on the front side of the base island formed in step 5 for chip implantation; Step 11. Wire Bonding Carry out bonding wire operation between the front surface of the first chip and the pins formed in step five; Step 12. Epoxy resin plastic sealing Epoxy resin plastic sealing protection is carried out on the front of the metal substrate after chip loading and wiring; Step 13. Epoxy resin surface grinding Surface grinding is carried out after completing the epoxy resin molding in step 12; Step 14. Paste photoresist film In step 13, a photoresist film that can be exposed and developed is pasted on the front and back of the metal substrate after the epoxy resin surface is ground; Step 15. Remove part of the photoresist film on the back of the metal substrate Use the exposure and development equipment to expose, develop and remove part of the graphic photoresist film on the back of the metal substrate that has been pasted with the photoresist film in step 14, so as to expose the area that needs to be etched later on the back of the metal substrate; Step 16. Etching Perform chemical etching in the region where part of the photoresist film is removed on the back of the metal substrate in step fifteen; Step seventeen, remove the photoresist film Remove the photoresist film on the surface of the metal substrate; Step 18. Cover the back of the metal substrate with green paint or photosensitive non-conductive adhesive Apply green paint or photosensitive non-conductive adhesive to the back of the metal substrate after removing the photoresist film in step seventeen; Step 19: Exposure, window development Use exposure and development equipment to expose and develop the green paint or photosensitive non-conductive adhesive on the back of the metal substrate to expose the area on the back of the metal substrate that needs to be electroplated with a high-conductivity metal layer; Step 20: Plating a highly conductive metal layer Electroplate a highly conductive metal layer in the window area of the green paint on the back of the metal substrate or photosensitive non-conductive adhesive in step 19; Step 21: Coating Antioxidant Antioxidant coating on the exposed metal surface of the metal substrate; Step 22. Stack Packages In step 21, the top of the conductive pillar covered with antioxidant is completed and the package is stacked through a conductive substance; Step 23. Cut the finished product Cutting the semi-finished products that have been stacked in step 22, so that the plastic package modules that were originally integrated in the form of an array assembly and containing chips are cut and separated one by one to obtain a three-dimensional system level that is sealed first and etched later. The chip is mounted on a stacked package structure. 2. A method for encapsulating first and then etching a three-dimensional system-on-a-chip stacked package structure, characterized in that the method comprises the following steps: Step 1. Take the metal substrate Step 2. Pre-plating copper on the surface of the metal substrate Pre-plating a layer of copper on the surface of the metal substrate; Step 3: Paste the photoresist film In step 2, a photoresist film that can be exposed and developed is pasted on the front and back of the metal substrate of the pre-plated copper material; Step 4. Remove part of the photoresist film from the front of the metal substrate Using exposure and development equipment, the front of the metal substrate that has completed the photoresist film pasting operation in step 3 is subjected to pattern exposure, development and removal of part of the pattern photoresist film, so as to expose the area on the front of the metal substrate that needs to be electroplated for the first metal circuit layer; Step 5. Electroplating the first metal circuit layer Electroplating the first metal circuit layer in the area where part of the photoresist film is removed from the front of the metal substrate in step 4; Step 6. Paste photoresist film In step 5, a photoresist film that can be exposed and developed is pasted on the front side of the metal substrate that has electroplated the first metal circuit layer; Step 7. Remove part of the photoresist film from the front of the metal substrate Use exposure and development equipment to expose, develop and remove part of the graphic photoresist film on the front of the metal substrate that has completed the photoresist film pasting operation in step 6, so as to expose the area that needs to be electroplated on the second metal circuit layer on the front of the metal substrate; Step 8. Electroplating the second metal circuit layer Electroplating the second metal circuit layer in the area where part of the photoresist film is removed on the front side of the metal substrate in step 7 as a conductive pillar for connecting the first metal circuit layer and the third metal circuit layer; Step 9. Remove the photoresist film Remove the photoresist film on the surface of the metal substrate; Step 10. Paste and press the non-conductive film Paste a layer of non-conductive adhesive film on the front of the metal substrate; Step 11. Grinding the surface of the non-conductive film Surface grinding is carried out after the non-conductive adhesive film is pasted and pressed in step ten; Step 12. Metallization pretreatment on the surface of the non-conductive film Carry out metallization pretreatment on the surface of the non-conductive adhesive film, so that the surface is attached with a layer of metallized polymer material or the surface is roughened; Step 13. Paste photoresist film Paste a photoresist film that can be exposed and developed on the front and back of the metal substrate that has completed the metallization pretreatment in step 12; Step 14. Remove part of the photoresist film from the front of the metal substrate Exposing, developing and removing part of the graphic photoresist film on the front of the metal substrate on which the photoresist film pasting operation has been completed in step 13 by using exposure and developing equipment, so as to expose the pattern of the area on the front of the metal substrate that needs to be etched later; Step 15. Etching Etching the area after opening the photoresist film on the front of the metal substrate in step 14; Step sixteen, remove the photoresist film Remove the photoresist film on the surface of the metal substrate; Step seventeen, electroplating the third metal circuit layer In step 15, the metallized pretreatment area retained after etching on the front side of the metal substrate is electroplated with a third metal circuit layer, and after the electroplating of the third metal circuit layer is completed, corresponding base islands and pins are formed on the front side of the metal substrate; Step 18. Paste photoresist film In step 17, a photoresist film that can be exposed and developed is pasted on the front side of the metal substrate on which the electroplating of the third metal circuit layer is completed; Step 19. Remove part of the photoresist film from the front of the metal substrate Using the exposure and developing equipment, perform graphic exposure, development and removal of part of the graphic photoresist film on the front of the metal substrate after step 18 has completed the operation of pasting the photoresist film, so as to expose the area on the front of the metal substrate that needs to be electroplated with conductive pillars; Step 20: Plating conductive pillars Electroplate conductive pillars in the area where part of the photoresist film is removed from the front of the metal substrate in step 19; Step 21. Remove the photoresist film Remove the photoresist film on the surface of the metal substrate; Step 22, loading film Coating conductive or non-conductive adhesive substance on the front side of the base island formed in step 17 to implant the first chip; Step 23. Metal wire bonding Carry out bonding wire operation between the front surface of the first chip and the pins formed in step five; Step 24: Epoxy resin molding Epoxy resin plastic sealing protection is carried out on the front of the metal substrate after chip loading and wiring; Step 25. Epoxy resin surface grinding Surface grinding is carried out after epoxy resin molding is completed in step 24; Step 26. Paste the photoresist film Paste a photoresist film that can be exposed and developed on the front and back of the metal substrate after the epoxy resin surface is ground in step 25; Step 27. Remove part of the photoresist film on the back of the metal substrate Use the exposure and development equipment to expose, develop and remove part of the graphic photoresist film on the back of the metal substrate after the photoresist film pasting operation in step 26, so as to expose the area that needs to be etched later on the back of the metal substrate; Step 28. Etching Perform chemical etching on the area where part of the photoresist film is removed on the back of the metal substrate in step 27; Step 29. Remove the photoresist film Remove the photoresist film on the surface of the metal substrate; Step 30. Cover the back of the metal substrate with green paint or photosensitive non-conductive adhesive After removing the photoresist film in step 29, coat the back of the metal substrate with green paint or photosensitive non-conductive adhesive; Step 31: Exposure, window development Use exposure and development equipment to expose and develop the green paint or photosensitive non-conductive adhesive on the back of the metal substrate to expose the area on the back of the metal substrate that needs to be electroplated with a high-conductivity metal layer; Step thirty-two, electroplating a highly conductive metal layer Electroplate a highly conductive metal layer in the window area of the green paint on the back of the metal substrate or photosensitive non-conductive adhesive in step 31; Step 33: Antioxidant Coating Antioxidant coating on the exposed metal surface of the metal substrate; Step 34. Stack Packages In step 33, complete the stacking of packages through conductive substances on top of the conductive pillars coated with antioxidants; Step 35. Cut the finished product The semi-finished product stacked in step 34 is cut, so that the plastic package modules that are originally integrated in the form of an array assembly and contain chips are cut and separated one by one, and the three-dimensional system level that is sealed first and etched later is obtained. The chip is mounted on a stacked package structure. 3. The process method of sealing first and then etching a three-dimensional system-on-a-chip stacked package structure according to claim 2, characterized in that: the steps 6 to 17 are repeated between steps 5 and 18 repeatedly.