CN102723289A - Normal chip single-faced three-dimensional circuit manufacture method by encapsulation prior to etching and normal chip single-faced three-dimensional circuit encapsulation structure - Google Patents

Abstract

The invention relates to a normal chip single-faced three-dimensional circuit manufacture method by encapsulation prior to etching. The method includes: taking a metal substrate; preplating copper to the metal substrate surface; coating with green paint; partially removing the green paint on the front of the metal substrate; electroplating inert a metal circuit layer; electroplating a metal circuit layer; coating with green paint; partially removing the green paint on the front of the metal substrate; electroplating a metal circuit layer; coating with green paint; partially removing the green paint on the front of the metal substrate; coating a circuit screen plate; performing metallization pretreatment; removing the circuit screen plate; electroplating metal circuit layer; coating bonding material; mounting a chip; performing metal circuit bonding; encapsulating; partially removing the green paint on the back of the metal substrate; performing chemical etching; electroplating a metal circuit layer; coating with green paint; reserving holes on the green paint; cleaning; attaching balls; and cutting finished products. The normal chip single-faced three-dimensional circuit manufacture method by encapsulation prior to etching has the advantages that manufacture cost is lowered, safety and reliability of encapsulation are enhanced, environmental pollution is reduced, and design and manufacture of high density circuit are really achieved.

Description

Chip front-mount single-sided three-dimensional circuit manufacturing method and packaging structure after sealing first and etching later

technical field

The invention relates to a method for manufacturing a single-sided three-dimensional circuit of a front-mounted chip by sealing first and then etching and the packaging structure thereof, belonging to the technical field of semiconductor packaging.

Background technique

The manufacturing process flow of the traditional high-density substrate package structure is as follows:

Step 1, referring to Figure 85, take a substrate made of glass fiber material,

Step 2, see Figure 86, make holes on the required position on the glass fiber substrate,

Step 3, see Figure 87, coat a layer of copper foil on the back of the glass fiber substrate,

Step 4, see Figure 88, fill in the conductive material at the position where the glass fiber substrate is punched,

Step 5, see Figure 89, coat a layer of copper foil on the front of the glass fiber substrate,

Step 6, see Figure 90, coat the photoresist film on the surface of the glass fiber substrate,

Step 7, see Figure 91, expose and develop the photoresist film at the required position to open the window,

Step 8, see Figure 92, etch the part where the window has been opened,

Step 9, see Figure 93, peel off the photoresist film on the surface of the substrate,

Step 10, see Figure 94, apply solder resist paint (commonly known as green paint) on the surface of the copper foil circuit layer,

Step 11. Referring to Figure 95, open the window in the area where the solder resist paint needs to be installed in the post-process and wire bonded.

Step 12, see Figure 96, perform electroplating on the area where the window is opened in step 11, and relatively form base islands and pins,

Step thirteen, complete subsequent related processes such as film loading, wire bonding, encapsulation, and cutting.

The above-mentioned traditional high-density substrate packaging structure has the following deficiencies and defects:

1. There is an extra layer of glass fiber material, and also the cost of an extra layer of glass fiber;

2. Because glass fiber must be used, there is an extra layer of glass fiber thickness of about 100~150μm;

3. Glass fiber itself is a kind of foaming material, so it is easy to absorb moisture and moisture due to the storage time and environment, which directly affects the safety capability or reliability level of reliability;

4. The surface of the glass fiber is covered with a copper foil metal layer thickness of about 50-100 μm, and the etching distance between the metal layer line and the line can only achieve an etching gap of 50-100 μm due to the characteristics of the etching factor (see Figure 97, The best production capacity is that the etching gap is approximately equal to the thickness of the etched object), so it is impossible to truly design and manufacture high-density circuits;

5. Because the copper foil metal layer must be used, and the copper foil metal layer is pasted by high pressure, so the thickness of the copper foil is difficult to be less than 50μm, otherwise it will be difficult to operate such as unevenness or copper foil damage Or the extension and displacement of copper foil, etc.;

6. Also because the entire substrate material is made of glass fiber material, the thickness of the glass fiber layer is obviously increased by 100~150 μm, and it is impossible to achieve ultra-thin packaging;

7. Due to the large difference in material properties (expansion coefficient), the traditional glass fiber plus copper foil technology is easy to cause stress deformation in the harsh environment process, which directly affects the accuracy of component loading and the adhesion and reliability of components and substrates. sex.

Contents of the invention

The object of the present invention is to overcome the above-mentioned shortcomings, and provide a method for manufacturing single-sided three-dimensional circuits of a chip, which is sealed first and then etched, and its packaging structure. Safety and reliability reduce the environmental pollution caused by glass fiber materials, and the metal substrate circuit layer adopts the electroplating method, which can truly achieve the design and manufacture of high-density circuits.

The object of the present invention is achieved like this: a kind of chip positively mounted single-sided three-dimensional circuit first seals back etching manufacturing method, and it comprises the following process steps:

Step 1. Take the metal substrate

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

Electroplate a layer of copper film on the surface of the metal substrate,

Step 3, green paint coating

In step 2, the front and back of the metal substrate of the pre-plated copper film are covered with green paint,

Step 4. Remove part of the green paint from the front of the metal substrate

Use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step 3, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 5. Electroplating inert metal circuit layer

Electroplate the inert metal circuit layer on the pattern area where the window has been opened on the front side of the metal substrate in step 4,

Step 6. Plating metal circuit layer

Metal circuit layer is plated on the surface of inert metal circuit layer in step five,

Step 7. Green paint coating

In step 6, the front side of the metal substrate on which the electroplating metal circuit layer is completed is covered with green paint again,

Step 8. Remove part of the green paint from the front of the metal substrate

Use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step 7, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate.

Step 9. Plating metal circuit layer

Electroplate the metal circuit layer on the pattern area where the window has been opened on the front of the metal substrate in step 8,

Step 10. Green paint coating

In step 9, the front of the metal substrate on which the electroplating metal circuit layer is completed is covered with green paint again,

Step 11. Remove part of the green paint from the front of the metal substrate

Use the exposure and development equipment to perform pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step ten, so as to expose the pattern area on the front of the metal substrate that needs to be electroplated later,

Step 12. Cover the circuit board

Cover the circuit board on the front of the metal substrate,

Step 13, pre-metallization treatment

Carry out pre-metallization treatment of the electroplated metal circuit layer on the graphic area where the window has been opened on the front side of the metal substrate in step 11,

Step 14. Remove the circuit board

Remove the circuit board covered on the front side of the metal substrate in step 12,

Step 15. Electroplating the metal circuit layer

The metal circuit layer is electroplated on the area where the metal circuit layer pretreatment is completed on the front side of the metal substrate in step 13. After the metal circuit layer is electroplated, pins or base islands and pins or base islands and lead islands are relatively formed on the front side of the metal substrate. feet and the upper part of the ESD collar,

Step 16. Apply the bonding substance

When only the upper part of the pin is relatively formed in step 15, a conductive or non-conductive adhesive substance is applied to the upper part of the pin; when the base island and the upper part of the pin are formed in step 15, or the base island, pin and electrostatic discharge When the upper part of the circle is applied, a conductive or non-conductive adhesive substance is coated on the upper surface of the base island,

Step seventeen, loading film

Chip implantation is carried out on the conductive or non-conductive adhesive substance coated on the front surface of the sixteen pins or the base island,

Step 18. Wire Bonding

Wire bonding between the front side of the chip and the front side of the pins,

Step nineteen, encapsulation

Encapsulate the front side of the metal substrate after step 18 has completed chip loading and wiring,

Step 20. Remove part of the green paint on the back of the metal substrate

Use exposure and development equipment to perform graphic exposure, development and window opening on the green paint coated on the back of the metal substrate to expose the pattern area on the back of the metal substrate that needs to be chemically etched later.

Step 21. Chemical etching

Perform chemical etching on the graphic area where the windows are opened on the back of the metal substrate in step 20,

Step 22: Electroplating the metal circuit layer

The surface of the inert metal circuit layer exposed after the chemical etching is completed in step 21 is electroplated on the metal circuit layer. After the electroplating of the metal circuit layer is completed, pins or base islands and pins or base islands and pins are relatively formed on the back of the metal substrate. and the lower part of the ESD collar,

Step 23, green paint coating

In step 22, the backside of the metal substrate of the electroplated metal circuit layer is covered with green paint;

Step 24. Open holes on the surface of the green paint

On the surface of the green paint coated on the back of the metal substrate in step 23, carry out the subsequent drilling work in the area where the metal balls will be planted,

Step twenty-five, cleaning

Clean the green paint opening on the back of the metal substrate in step 24

Step twenty-six, planting the ball

Insert a metal ball into the cleaned hole in step 25,

Step 27. Cut the finished product

Cut the semi-finished products that have been ball-planted in step 26, so that the plastic package modules that were originally integrated in the form of an array assembly and contain chips are cut and separated one by one to obtain a single-sided three-dimensional circuit-first package for chip packaging The finished package structure is etched back.

A packaging structure of a single-sided three-dimensional circuit on a chip is sealed first and then etched. It includes pins, and the front of the pins is provided with a chip through a conductive or non-conductive adhesive substance. Connected with metal wires, the peripheral area of the pins, the area between the pins and the lower part of the pins are covered with green paint, and the upper part of the pins and the outer chip and metal wires are covered with green paint. Molding compound, the green paint surface of the lower part of the pin is provided with a small hole, the small hole communicates with the back of the pin, and a metal ball is arranged in the small hole, and the metal ball is in contact with the back of the pin.

In the twenty-fifth step, the green paint opening on the back of the metal substrate is cleaned and the metal protective layer is coated at the same time.

The packaging structure includes a base island, and at this time, the chip is arranged on the front surface of the base island through a conductive or non-conductive adhesive substance.

There are single or multiple base islands.

An electrostatic discharge ring is arranged between the base island and the pins, and the front of the electrostatic discharge ring is connected to the front of the chip by a metal wire. the

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

1. The present invention does not need to use the glass fiber layer, so the cost brought by the glass fiber layer can be reduced;

2. The present invention does not use the foaming material of the glass fiber layer, so the reliability level can be further improved, and the relative safety of the package will be improved;

3. The present invention does not need to use glass fiber material, so the environmental pollution caused by glass fiber material can be reduced;

4. The circuit layer of the three-dimensional metal substrate of the present invention adopts the electroplating method, and the total thickness of the electroplating layer is about 10-15 μm, and the gap between the lines can easily reach a gap below 25 μm, so it can be truly The technical ability to achieve high-density internal pin line tiling;

5. The three-dimensional metal substrate of the present invention adopts the metal layer electroplating method, so it is simpler than the process of glass fiber high-voltage copper foil metal layer, and there will be no metal layer unevenness, metal layer damage and metal layer due to high pressure. Poor or confused layer extension and displacement;

6. The three-dimensional metal substrate circuit layer of the present invention is metal electroplated on the surface of the metal substrate, so the material properties are basically the same, so the internal stress of the plating circuit and the metal substrate is basically the same, and the post-engineering in harsh environments can be easily carried out ( Such as high-temperature eutectic chip mounting, high-temperature tin solder chip mounting, and surface mount work of high-temperature passive components) are not prone to stress deformation.

Description of drawings

Figures 1 to 27 are schematic diagrams of each process in Embodiment 1 of the method for manufacturing a single-sided three-dimensional circuit on a front-mounted chip of the present invention, which is sealed first and then etched.

Fig. 28 is a structural schematic diagram of Embodiment 1 of the chip front-mount single-sided three-dimensional circuit sealing first and then etching packaging structure of the present invention.

29 to 55 are schematic diagrams of each process in Embodiment 2 of the manufacturing method of first sealing and then etching the single-sided three-dimensional circuit of the chip of the present invention.

Fig. 56 is a structural schematic diagram of Embodiment 2 of the chip front-mounted single-sided three-dimensional circuit sealing structure first and then etched.

57 to 83 are schematic diagrams of each process in Embodiment 3 of the method for manufacturing a single-sided three-dimensional circuit on a front-mounted chip of the present invention, which is sealed first and then etched.

Fig. 84 is a structural schematic diagram of Embodiment 3 of the front-mounted single-sided three-dimensional circuit packaging structure of the present invention, which is sealed first and then etched.

85 to 96 are schematic diagrams of each process of the manufacturing process flow of the traditional high-density substrate packaging structure.

Fig. 97 is a schematic diagram of the etching status of the copper foil metal layer on the surface of the glass fiber.

in:

Metal Substrate 1

Copper film 2

Green paint 3

Inert metal wiring layer 4

metal line layer 5

Circuit board 6

Metallization pretreatment layer 7

Conductive or non-conductive bonding substances8

Chip 9

metal wire 10

Plastic compound 11

Small hole 12

Metal protection layer 13

metal ball 14

pin 15

Key Island 16

Electrostatic discharge ring 17.

Detailed ways

The manufacturing method of the chip front-mounted single-sided three-dimensional circuit of the present invention is sealed first and then etched, including the following process steps:

Embodiment 1, no base island

Step 1. Take the metal substrate

Referring to Figure 1, take a metal substrate with a suitable thickness. The material of the metal substrate can be changed according to the functions and characteristics of the chip, for example: copper, iron, nickel-iron or zinc-iron;

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

Referring to Figure 2, a layer of copper film is electroplated on the surface of the metal substrate, the purpose is to serve as the basis for subsequent electroplating, and the electroplating method can be electroless plating or electrolytic plating;

Step 3, green paint coating

Referring to Figure 3, in step 2, the front and back of the metal substrate of the pre-plated copper film are covered with green paint to protect the subsequent electroplating metal layer process operations;

Step 4. Remove part of the green paint from the front of the metal substrate

Referring to Figure 4, use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step 3, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 5. Electroplating inert metal circuit layer

Referring to Fig. 5, an inert metal circuit layer is electroplated on the graphic area where the window has been opened on the front side of the metal substrate in step four, as a barrier layer for subsequent etching operations. The material of the inert metal circuit layer is nickel, titanium or copper, etc., and the electroplating The method adopts chemical plating or electrolytic plating;

Step 6. Plating metal circuit layer

Referring to Fig. 6, a metal circuit layer is plated on the surface of the inert metal circuit layer in step five, and the metal circuit layer can be single-layer or multilayer, and the material of the metal circuit layer is silver, aluminum, copper, nickel gold or nickel Palladium, gold, etc., the electroplating method can be chemical plating or electrolytic plating;

Step 7. Green paint coating

Referring to Fig. 7, in step 6, the front of the metal substrate of the electroplated metal circuit layer is covered with green paint again to protect the subsequent electroplating metal layer process operations;

Step 8. Remove part of the green paint from the front of the metal substrate

Referring to Figure 8, use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step 7, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 9. Plating metal circuit layer

Referring to Fig. 9, the metal circuit layer is electroplated on the graphic area where the window has been opened on the front side of the metal substrate in step eight. The metal circuit layer can be a single layer or multiple layers, and the metal circuit layer material is silver, aluminum, copper, nickel Gold or nickel-palladium-gold, etc., the electroplating method can be chemical electroplating or electrolytic electroplating;

Step 10. Green paint coating

Referring to FIG. 10 , in step 9, the front side of the metal substrate on which the electroplating metal circuit layer is completed is coated with green paint again to protect the subsequent electroplating metal layer process operations;

Step 11. Remove part of the green paint from the front of the metal substrate

Referring to Fig. 11, use the exposure and development equipment to perform pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step ten, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 12. Cover the circuit board

Referring to Figure 12, the front of the metal substrate is covered with a circuit board, and the circuit board covers the area that does not need to be metallized in the future;

Step 13, pre-metallization treatment

Referring to Figure 13, perform metallization pre-treatment on the metallization circuit layer of the electroplated metal circuit layer on the graphics area on the front of the metal substrate in step 11. The pre-metallization method can be coating, spraying, printing, shower coating or immersion Way;

Step 14. Remove the circuit board

Referring to Figure 14, remove the circuit board covered on the front side of the metal substrate in step 12;

Step 15. Electroplating the metal circuit layer

Referring to Fig. 15, the metal circuit layer is electroplated on the area where the metal circuit layer pretreatment is completed on the front side of the metal substrate in step 13. After the metal circuit layer is electroplated, the upper part of the pin is relatively formed on the front side of the metal substrate. The metal circuit layer The layer can be single-layer or multi-layer, and the material of the metal circuit layer is silver, aluminum, copper, nickel-gold or nickel-palladium-gold, etc. The electroplating method can be chemical electroplating or electrolytic electroplating;

Step 16. Apply the bonding substance

Referring to Fig. 16, the upper surface of the upper part of the pins formed oppositely in step fifteen is coated with a conductive or non-conductive adhesive substance, the purpose of which is to bond with the pins after the subsequent chip implantation;

Step seventeen, loading film

Referring to Fig. 17, chip implantation is carried out on the conductive or non-conductive bonding substance coated on the upper surface of the sixteen pins;

There can be one or more chips implanted. If there are multiple chips implanted, the metal wire bonding operation between the front of the chip and the front of the chip will be carried out later;

Step 18. Wire Bonding

Referring to Figure 18, the metal wire bonding operation is carried out between the front side of the chip and the front side of the pin. The material of the metal wire is gold, silver, copper, aluminum or alloy materials, and the shape of the metal wire can be filament or ribbon. shape;

Step nineteen, encapsulation

Referring to Figure 19, encapsulate the front of the metal substrate after step 18 has been loaded and wired. The encapsulation method of the plastic compound can be mold filling, spraying or brushing. The plastic compound can be Epoxy resins with or without fillers;

Step 20. Remove part of the green paint on the back of the metal substrate

Referring to Fig. 20, the green paint coated on the back of the metal substrate is exposed, developed, and opened with an exposure and developing device to expose the graphic area that needs to be chemically etched on the back of the metal substrate;

Step 21. Chemical etching

Referring to Fig. 21, chemically etch the graphic area where the window is opened on the back of the metal substrate in step 20, until the position of the inert metal circuit layer is chemically etched, and the etching solution can be copper chloride or ferric chloride;

Step 22: Electroplating the metal circuit layer

Referring to FIG. 22, the surface of the inert metal circuit layer exposed after the chemical etching in step 21 is electroplated on the metal circuit layer. After the metal circuit layer is electroplated, the lower part of the pin is relatively formed on the back of the metal substrate. The metal circuit layer It can be single-layer or multi-layer, and the material of the metal circuit layer is copper-nickel-gold, copper-nickel-silver, palladium-gold, gold or copper, etc., and the electroplating method can be chemical plating or electrolytic plating;

Step 23, green paint coating

Referring to FIG. 23 , in step 22, the backside of the metal substrate of the electroplated metal circuit layer is covered with green paint;

Step 24. Open holes on the surface of the green paint

Referring to FIG. 24 , in step 23, the green paint surface coated on the back of the metal substrate is followed by opening operations in the area where metal balls are to be planted. The opening method can be dry laser sintering or wet chemical etching;

Step twenty-five, cleaning

Referring to Figure 25, clean the openings of the green paint on the back of the metal substrate in step 24 to remove oxidized substances or organic substances, etc., and at the same time coat the metal protective layer, which uses an antioxidant;

Step twenty-six, planting the ball

Referring to Figure 26, metal balls are implanted in the cleaned holes in step 25, and the metal balls are in contact with the back of the pins. The ball planting method can be a conventional ball planting machine or a metal paste printing process. Spheroids can be formed after high-temperature dissolution, and the material of the metal balls can be pure tin or tin alloy;

Step 27. Cut the finished product

Referring to Figure 27, the semi-finished product that has completed the ball planting in step 26 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 single-sided chip is obtained. The three-dimensional circuit is first sealed and then etched into the finished package structure.

The packaging structure of Embodiment 1 is as follows:

Referring to Fig. 28, the present invention has a single-sided three-dimensional circuit packaging structure that is first sealed and then etched. It includes pins 15, and the front side of the pins 15 is provided with a chip 9 through a conductive or non-conductive adhesive material 8. The front side of the chip 9 Connect with the front of the pin 15 with a metal wire 10, the area around the pin 15, the area between the pin 15 and the pin 15, and the area below the pin 15 are encapsulated with green paint 3, the The upper area of the pin 15 and the chip 9 and the metal wire 10 are encapsulated with a plastic encapsulant 11, and the green paint 3 at the lower part of the pin 15 is provided with a small hole 12 on the surface, and the small hole 12 communicates with the back of the pin 15 , a metal ball 14 is arranged in the small hole 12, the metal ball 14 is in contact with the back of the pin 15, and a metal protective layer 13 is arranged between the metal ball 14 and the back of the pin 15, and the metal protective layer 13 is an antioxidant.

Embodiment 2, there is base island

Step 1. Take the metal substrate

Referring to Figure 29, take a metal substrate with a suitable thickness. The material of the metal substrate can be changed according to the functions and characteristics of the chip, for example: copper, iron, nickel-iron or zinc-iron;

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

Referring to Figure 30, a layer of copper film is electroplated on the surface of the metal substrate, the purpose is to serve as the basis for subsequent electroplating, and the electroplating method can be electroless plating or electrolytic plating;

Step 3, green paint coating

Referring to Figure 31, in step 2, the front and back of the metal substrate of the pre-plated copper film are covered with green paint to protect the subsequent electroplating metal layer process;

Step 4. Remove part of the green paint from the front of the metal substrate

Referring to Figure 32, use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step 3, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 5. Electroplating inert metal circuit layer

Referring to Fig. 33, electroplating an inert metal circuit layer on the graphic area of the front of the metal substrate in step 4 where the window has been opened is used as a barrier layer for subsequent etching operations. The material of the inert metal circuit layer is nickel, titanium or copper, etc., and the electroplating The method adopts chemical plating or electrolytic plating;

Step 6. Plating metal circuit layer

Referring to Fig. 34, a metal circuit layer is plated on the surface of the inert metal circuit layer in step five, and the metal circuit layer can be a single layer or multiple layers, and the material of the metal circuit layer is silver, aluminum, copper, nickel gold or nickel Palladium, gold, etc., the electroplating method can be chemical plating or electrolytic plating;

Step 7. Green paint coating

Referring to FIG. 35 , in step six, the front of the metal substrate on which the electroplating metal circuit layer is completed is coated with green paint again to protect the subsequent electroplating metal layer process operations;

Step 8. Remove part of the green paint from the front of the metal substrate

Referring to Figure 36, use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate covered with green paint in step 7, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 9. Plating metal circuit layer

Referring to Fig. 37, electroplate the metal circuit layer on the graphic area where the window has been opened on the front side of the metal substrate in step eight. The metal circuit layer can be single-layer or multi-layer. The material of the metal circuit layer is silver, aluminum, copper, nickel Gold or nickel-palladium-gold, etc., the electroplating method can be chemical electroplating or electrolytic electroplating;

Step 10. Green paint coating

Referring to FIG. 38 , in step nine, the front of the metal substrate on which the electroplating metal circuit layer is completed is coated with green paint again to protect the subsequent electroplating metal layer process operations;

Step 11. Remove part of the green paint from the front of the metal substrate

Referring to Fig. 39, use the exposure and development equipment to perform graphic exposure, development and window opening on the front of the metal substrate coated with green paint in step ten, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 12. Cover the circuit board

Referring to Fig. 40, the circuit board is covered on the front of the metal substrate, and the circuit board covers the area that does not need to be metallized in the future;

Step 13, pre-metallization treatment

Referring to Figure 41, perform metallization pre-treatment on the metallized circuit layer on the pattern area where the window has been opened on the front side of the metal substrate in step 11. The metallization pre-treatment method can be coating, spraying, printing or flow coating;

Step 14. Remove the circuit board

Referring to Figure 42, remove the circuit board covered on the front side of the metal substrate in step 12;

Step 15. Electroplating the metal circuit layer

Referring to Fig. 43, the metal circuit layer is electroplated on the area where the pre-treatment of the metal circuit layer is electroplated on the front of the metal substrate in step 13. After the metal circuit layer is electroplated, the base island and the upper part of the pin are relatively formed on the front of the metal substrate. The metal circuit layer can be single-layer or multi-layer, and the material of the metal circuit layer is silver, aluminum, copper, nickel-gold or nickel-palladium-gold, etc. The electroplating method can be chemical electroplating or electrolytic electroplating;

Step 16. Apply the bonding substance

Referring to Fig. 44, a conductive or non-conductive adhesive substance is coated on the upper surface of the base island formed oppositely in step fifteen, for the purpose of bonding with the pins after subsequent chip implantation;

Step seventeen, loading film

Referring to FIG. 45, chip implantation is carried out on the conductive or non-conductive adhesive substance coated on the upper surface of the sixteen base island in the step;

There can be one or more chips implanted. If there are multiple chips implanted, the metal wire bonding operation between the front of the chip and the front of the chip will be carried out later;

Step 18. Wire Bonding

Referring to Figure 46, the metal wire is bonded between the front side of the chip and the front side of the pin. The material of the metal wire is gold, silver, copper, aluminum or an alloy material, and the shape of the metal wire can be filament or ribbon. shape;

Step nineteen, encapsulation

Referring to Fig. 47, encapsulate the front side of the metal substrate after step 18 is finished with chip loading and wire bonding. The encapsulation method of the plastic compound can be mold filling, spraying or brushing. The plastic compound can be Epoxy resins with or without fillers;

Step 20. Remove part of the green paint on the back of the metal substrate

Referring to Fig. 48, the green paint coated on the back of the metal substrate is exposed, developed, and opened with an exposure and developing device to expose the pattern area that needs to be chemically etched on the back of the metal substrate;

Step 21. Chemical etching

Referring to Fig. 49, chemically etch the graphic area where the window is opened on the back of the metal substrate in step 20 until the position of the inert metal circuit layer is chemically etched. The etching solution can be copper chloride or ferric chloride;

Step 22: Electroplating the metal circuit layer

Referring to FIG. 50 , the surface of the inert metal circuit layer exposed after the chemical etching is completed in step 21 is electroplated on the metal circuit layer. After the metal circuit layer is electroplated, the base island and the lower part of the pin are relatively formed on the back of the metal substrate. The metal circuit layer can be single-layer or multi-layer, and the material of the metal circuit layer is copper-nickel-gold, copper-nickel-silver, palladium-gold, gold or copper, etc. The electroplating method can be chemical electroplating or electrolytic electroplating;

Step 23, green paint coating

Referring to FIG. 51 , in step 22, the backside of the metal substrate on which the metal circuit layer is electroplated is covered with green paint;

Step 24. Open holes on the surface of the green paint

Referring to Fig. 52, on the surface of the green paint coated on the back of the metal substrate in step 23, the hole opening operation of the area to be planted with metal balls is carried out. The hole opening method can be dry laser sintering or wet chemical etching;

Step twenty-five, cleaning

Referring to Figure 53, clean the openings of the green paint on the back of the metal substrate in step 24 to remove oxidized substances or organic substances, and at the same time coat the metal protective layer, which uses an antioxidant;

Step twenty-six, planting the ball

Referring to Figure 54, metal balls are implanted in the cleaned holes in step 25, and the metal balls are in contact with the back of the pins. The ball planting method can be a conventional ball planting machine or a metal paste printing process. Spheroids can be formed after high-temperature dissolution, and the material of the metal balls can be pure tin or tin alloy;

Step 27. Cut the finished product

Referring to Figure 55, the semi-finished products that have completed the ball planting in step 26 are cut, so that the plastic package modules that are originally integrated in an array form and contain chips are cut and separated one by one, and the single-sided chips are obtained. The three-dimensional circuit is first sealed and then etched into the finished package structure.

The packaging structure of the second embodiment is as follows:

Referring to Fig. 56 , the package structure of the present invention for front-mounted single-sided three-dimensional circuit sealing before etching includes a base island 16 and pins 15, and the front side of the base island 16 is provided with a chip 9 through a conductive or non-conductive adhesive material 8, so that The front of the chip 9 is connected with the front of the pin 15 with a metal wire 10, the area around the base island 16, the area between the base island 16 and the pin 15, and the area between the pin 15 and the pin 15 And the area of the base island 16 and the lower part of the pin 16 is encapsulated with green paint 3, the area of the base island 16 and the upper part of the pin 15, as well as the chip 9 and the metal wire 10 are encapsulated with a plastic encapsulant 11, and the lower part of the pin 15 A small hole 12 is provided on the surface of the green paint 3, and the small hole 12 communicates with the back of the pin 15. A metal ball 14 is arranged in the small hole 12, and the metal ball 14 is in contact with the back of the pin 15. A metal protection layer 13 is provided between the metal ball 14 and the back of the pin 15, and the metal protection layer 13 is an antioxidant.

Embodiment 3, there is an electrostatic discharge ring with a base island

Step 1. Take the metal substrate

Referring to Figure 57, take a metal substrate with a suitable thickness. The material of the metal substrate can be changed according to the functions and characteristics of the chip, for example: copper, iron, nickel-iron or zinc-iron;

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

Referring to Figure 58, a layer of copper film is electroplated on the surface of the metal substrate, the purpose is to serve as the basis for subsequent electroplating, and the electroplating method can be electroless plating or electrolytic plating;

Step 3, green paint coating

Referring to Figure 59, in step 2, the front and back of the metal substrate of the pre-plated copper film are covered with green paint to protect the subsequent electroplating metal layer process;

Step 4. Remove part of the green paint from the front of the metal substrate

Referring to Figure 60, use the exposure and developing equipment to complete the pattern exposure, development and window opening on the front of the metal substrate covered with green paint in step 3, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 5. Electroplating inert metal circuit layer

Referring to Fig. 61, electroplating an inert metal circuit layer on the graphic area of the front side of the metal substrate that has been windowed in Step 4, as a barrier layer for subsequent etching operations, the material of the inert metal circuit layer is nickel, titanium or copper, etc., and the electroplating The method adopts chemical plating or electrolytic plating;

Step 6. Plating metal circuit layer

Referring to Fig. 62, a metal circuit layer is plated on the surface of the inert metal circuit layer in step five, and the metal circuit layer can be a single layer or multiple layers, and the material of the metal circuit layer is silver, aluminum, copper, nickel gold or nickel Palladium, gold, etc., the electroplating method can be chemical plating or electrolytic plating;

Step 7. Green paint coating

Referring to FIG. 63 , in step six, the front side of the metal substrate on which the electroplating metal circuit layer is completed is coated with green paint again to protect the subsequent electroplating metal layer process operations;

Step 8. Remove part of the green paint from the front of the metal substrate

Referring to Figure 64, use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step 7, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 9. Plating metal circuit layer

Referring to Fig. 65, electroplate the metal circuit layer on the graphic area where the window has been opened on the front side of the metal substrate in step eight. The metal circuit layer can be single layer or multi-layer, and the material of the metal circuit layer is silver, aluminum, copper, nickel Gold or nickel-palladium-gold, etc., the electroplating method can be chemical electroplating or electrolytic electroplating;

Step 10. Green paint coating

Referring to FIG. 66 , in step nine, the front of the metal substrate on which the electroplating metal circuit layer is completed is coated with green paint again to protect the subsequent electroplating metal layer process operations;

Step 11. Remove part of the green paint from the front of the metal substrate

Referring to Figure 67, use the exposure and development equipment to perform pattern exposure, development and window opening on the front of the metal substrate covered with green paint in step ten, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate;

Step 12. Cover the circuit board

Referring to Fig. 68, the circuit board is covered on the front of the metal substrate, and the circuit board covers the area that does not need to be metallized in the future;

Step 13, pre-metallization treatment

Referring to Figure 69, perform metallization pre-treatment on the metallized circuit layer on the graphic area where the window has been opened on the front of the metal substrate in step eleven. Way;

Step 14. Remove the circuit board

Referring to Figure 70, remove the circuit board covered on the front side of the metal substrate in step 12;

Step 15. Electroplating the metal circuit layer

Referring to Figure 71, the metal circuit layer is electroplated on the area where the pretreatment of the electroplating metal circuit layer is completed on the front of the metal substrate in step 13. After the electroplating of the metal circuit layer is completed, the base island, pins and electrostatic discharge rings are relatively formed on the front of the metal substrate The upper part of the metal circuit layer can be single-layer or multi-layer, and the material of the metal circuit layer is silver, aluminum, copper, nickel-gold or nickel-palladium-gold, etc., and the electroplating method can be chemical plating or electrolytic plating The way;

Step 16. Apply the bonding substance

Referring to Fig. 72, a conductive or non-conductive adhesive substance is coated on the upper surface of the base island formed oppositely in step fifteen, for the purpose of bonding with the pins after subsequent chip implantation;

Step seventeen, loading film

Referring to FIG. 73 , chip implantation is performed on the conductive or non-conductive adhesive substance coated on the upper surface of the sixteen base island in the step;

There can be one or more chips implanted. If there are multiple chips implanted, the metal wire bonding operation between the front of the chip and the front of the chip will be carried out later;

Step 18. Wire Bonding

Referring to Figure 74, the metal wire bonding operation is performed between the front of the chip and the front of the pins and between the front of the chip and the electrostatic discharge ring. The material of the metal wire is gold, silver, copper, aluminum or an alloy material, and the metal wire The shape can be filament or ribbon;

Step nineteen, encapsulation

Referring to Figure 75, encapsulate the front of the metal substrate after step 18 has been loaded and wired. The encapsulation method of the plastic compound can be mold filling, spraying or brushing. The plastic compound can be Epoxy resins with or without fillers;

Step 20. Remove part of the green paint on the back of the metal substrate

Referring to Fig. 76, the green paint coated on the back of the metal substrate is subjected to graphic exposure, development and window opening by using the exposure and development equipment, so as to expose the pattern area on the back of the metal substrate that needs to be subsequently chemically etched;

Step 21. Chemical etching

Referring to Fig. 77, chemically etch the graphic area where the window is opened on the back of the metal substrate in step 20, until the position of the inert metal circuit layer is chemically etched, and the etching solution can be copper chloride or ferric chloride;

Step 22: Electroplating the metal circuit layer

Referring to FIG. 78, the surface of the inert metal circuit layer exposed after the chemical etching in step 21 is electroplated on the metal circuit layer. After the metal circuit layer is electroplated, base islands, pins and electrostatic discharge rings are relatively formed on the back of the metal substrate. In the lower part, the metal circuit layer can be single-layer or multi-layer, and the material of the metal circuit layer is copper-nickel-gold, copper-nickel-silver, palladium-gold, gold or copper, etc., and the electroplating method can be electroless plating or electrolytic plating ;

Step 23, green paint coating

Referring to FIG. 79 , in step 22, the backside of the metal substrate on which the metal circuit layer is electroplated is covered with green paint;

Step 24. Open holes on the surface of the green paint

Referring to FIG. 80 , on the surface of the green paint coated on the back of the metal substrate in step 23, the hole opening operation of the area to be planted with metal balls is carried out. The hole opening method can be dry laser sintering or wet chemical etching;

Step twenty-five, cleaning

Referring to Figure 81, clean the green paint opening on the back of the metal substrate in step 24 to remove oxidized substances or organic substances, and at the same time coat the metal protective layer, which uses an antioxidant;

Step twenty-six, planting the ball

Referring to Figure 82, metal balls are implanted in the cleaned holes in step 25, and the metal balls are in contact with the back of the pins. The ball planting method can be a conventional ball planting machine or metal paste printing and then printed. Spheroids can be formed after high-temperature dissolution, and the material of the metal balls can be pure tin or tin alloy;

Step 27. Cut the finished product

Referring to Figure 93, the semi-finished product that has completed the ball planting in step 26 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 single-sided chip is obtained. The three-dimensional circuit is first sealed and then etched into the finished package structure.

The packaging structure of the third embodiment is as follows:

Referring to Fig. 84 , the package structure of the present invention, which is a single-sided three-dimensional circuit, is sealed first and then etched. It includes a base island 16 and pins 15, and an electrostatic discharge ring 17 is arranged between the base island 16 and the pins 15. The front of the island 16 is provided with a chip 9 through a conductive or non-conductive adhesive substance 8, and the front of the chip 9 and the front of the pin 15 and between the front of the chip 9 and the electrostatic discharge ring 17 are connected with a metal wire 10. The area around the island 16, the area between the base island 16 and the pin 15, the area between the pin 15 and the pin 15, and the area under the base island 16 and the pin 15 are encapsulated with green paint 3, the base The area above the island 16 and the pin 15, as well as the chip 9 and the metal wire 10 are encapsulated with a plastic encapsulant 11, and the green paint 3 at the bottom of the pin 15 is provided with a small hole 12 on the surface, and the small hole 12 is connected to the pin 15. The back is connected, and a metal ball 14 is arranged in the small hole 12, and the metal ball 14 is in contact with the back of the pin 15, and a metal protective layer 13 is arranged between the metal ball 14 and the back of the pin 15. The metal protective layer 13 is an antioxidant.

Claims (6)

1. A method for manufacturing a single-sided three-dimensional circuit of a chip by sealing first and then etching, is characterized in that the method comprises the following process steps: Step 1. Take the metal substrate Step 2. Pre-plating copper on the surface of the metal substrate Electroplate a layer of copper film on the surface of the metal substrate, Step 3, green paint coating In step 2, the front and back of the metal substrate of the pre-plated copper film are covered with green paint, Step 4. Remove part of the green paint from the front of the metal substrate Use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step 3, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate; Step 5. Electroplating inert metal circuit layer Electroplate the inert metal circuit layer on the pattern area where the window has been opened on the front side of the metal substrate in step 4, Step 6. Plating metal circuit layer Metal circuit layer is plated on the surface of inert metal circuit layer in step five, Step 7. Green paint coating In step 6, the front side of the metal substrate on which the electroplating metal circuit layer is completed is covered with green paint again, Step 8. Remove part of the green paint from the front of the metal substrate Use the exposure and development equipment to complete the pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step 7, so as to expose the pattern area that needs to be electroplated on the front of the metal substrate. Step 9. Plating metal circuit layer Electroplate the metal circuit layer on the pattern area where the window has been opened on the front of the metal substrate in step 8, Step 10. Green paint coating In step 9, the front of the metal substrate on which the electroplating metal circuit layer is completed is covered with green paint again, Step 11. Remove part of the green paint from the front of the metal substrate Use the exposure and development equipment to perform pattern exposure, development and window opening on the front of the metal substrate coated with green paint in step ten, so as to expose the pattern area on the front of the metal substrate that needs to be electroplated later, Step 12. Cover the circuit board Cover the circuit board on the front of the metal substrate, Step 13, pre-metallization treatment Carry out pre-metallization treatment of the electroplated metal circuit layer on the graphic area where the window has been opened on the front side of the metal substrate in step 11, Step 14. Remove the circuit board Remove the circuit board covered on the front side of the metal substrate in step 12, Step 15. Electroplating the metal circuit layer The metal circuit layer is electroplated on the area where the metal circuit layer pretreatment is completed on the front side of the metal substrate in step 13. After the metal circuit layer is electroplated, pins or base islands and pins or base islands and lead islands are relatively formed on the front side of the metal substrate. feet and the upper part of the ESD collar, Step 16. Apply the bonding substance When only the upper part of the pin is relatively formed in step 15, a conductive or non-conductive adhesive substance is applied to the upper part of the pin; when the base island and the upper part of the pin are formed in step 15, or the base island, pin and electrostatic discharge When the upper part of the circle is applied, a conductive or non-conductive adhesive substance is coated on the upper surface of the base island, Step seventeen, loading film Chip implantation is carried out on the conductive or non-conductive bonding substance coated on the front surface of the sixteen pins or the base island, Step 18. Wire Bonding Wire bonding between the front side of the chip and the front side of the pins, Step nineteen, encapsulation Encapsulate the front side of the metal substrate after step 18 has completed chip loading and wiring, Step 20. Remove part of the green paint on the back of the metal substrate Use exposure and development equipment to perform graphic exposure, development and window opening on the green paint coated on the back of the metal substrate to expose the pattern area on the back of the metal substrate that needs to be chemically etched later. Step 21. Chemical etching Perform chemical etching on the graphic area where the windows are opened on the back of the metal substrate in step 20, Step 22: Electroplating the metal circuit layer The surface of the inert metal circuit layer exposed after the chemical etching is completed in step 21 is electroplated on the metal circuit layer. After the electroplating of the metal circuit layer is completed, pins or base islands and pins or base islands and pins are relatively formed on the back of the metal substrate. and the lower part of the ESD collar, Step 23, green paint coating In step 22, the backside of the metal substrate of the electroplated metal circuit layer is covered with green paint; Step 24. Open holes on the surface of the green paint On the surface of the green paint coated on the back of the metal substrate in step 23, carry out the subsequent drilling work in the area where the metal balls will be planted, Step twenty-five, cleaning Clean the green paint opening on the back of the metal substrate in step 24 Step twenty-six, planting the ball Insert a metal ball into the cleaned hole in step 25, Step 27. Cut the finished product Cut the semi-finished products that have been ball-planted in step 26, so that the plastic package modules that were originally integrated in the form of an array assembly and contain chips are cut and separated one by one to obtain a single-sided three-dimensional circuit-first package for chip packaging The finished package structure is etched back. 2. A package structure according to claim 1, which is a method of manufacturing a single-sided three-dimensional circuit with a chip and is sealed first, and then etched. The conductive adhesive substance (8) is provided with a chip (9), the front of the chip (9) is connected with the front of the pin (15) by a metal wire (10), and the peripheral area of the pin (15), The area between the pins (15) and the area below the pins (15) is encapsulated with green paint (3), and the area above the pins (15) and the chip (9) and metal The wire (10) is covered with plastic compound (11), and the green paint (3) on the lower part of the pin (15) has a small hole (12) on the surface, and the small hole (12) is connected with the pin (15) The back side is connected, and a metal ball (14) is arranged in the small hole (12), and the metal ball (14) is in contact with the back side of the pin (15). 3. A method for manufacturing a single-sided three-dimensional circuit of a chip according to claim 1, wherein said step 25 cleans the opening of the green paint on the back of the metal substrate and at the same time carries out the metal protection layer Covered. 4. The packaging structure of a chip front-mounted single-sided three-dimensional circuit manufacturing method of sealing first and then etching according to claim 2, characterized in that: the packaging structure includes a base island (16), and at this time, the chip (9) is conductive Or the non-conductive bonding substance (8) is arranged on the front of the base island (16). 5 . The packaging structure according to claim 4 , characterized in that: the base island ( 16 ) has single or multiple base islands ( 16 ). 6. The packaging structure according to claim 4, wherein a single-sided three-dimensional circuit of a chip is sealed first and then etched. A ring (17), the front of the static discharge ring (17) is connected to the front of the chip (9) through a metal wire (10).

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