CN102723288A - Flip chip single-faced three-dimensional circuit manufacture method by encapsulation prior to etching and flip chip single-faced three-dimensional circuit encapsulation structure - Google Patents

Abstract

The invention relates to a manufacturing method of chip flip-chip single-sided three-dimensional circuit, which includes the following process steps: taking a metal substrate; pre-plating copper on the surface of the metal substrate; coating with green paint; removing part of the green paint from the front of the metal substrate; Electroplating inert metal circuit layer; electroplating metal circuit layer; green paint coating; removing part of the green paint on the front of the metal substrate; electroplating metal circuit layer; green paint coating; removing part of the green paint on the front of the metal substrate; Pre-treatment; removal of circuit board; electroplating metal circuit layer; chip loading and chip underfill; encapsulation; removal of part of the green paint on the back of the metal substrate; chemical etching; electroplating metal circuit layer; ; Cleaning; Planting balls; Cutting finished products. The beneficial effects of the invention are: the manufacturing cost is reduced, the safety and reliability of the packaging body are improved, the environmental pollution is reduced, and the design and manufacture of high-density circuits can be truly achieved.

Description

Flip-chip single-sided three-dimensional circuit manufacturing method and packaging structure after sealing first and etching later

technical field

The invention relates to a chip flip-chip single-sided three-dimensional circuit manufacturing method which is first sealed and then etched and its packaging structure, which belongs 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 53, take a substrate made of glass fiber material,

Step 2, see Figure 54, make holes on the required position on the glass fiber substrate,

Step 3, see Figure 55, coat a layer of copper foil on the back of the glass fiber substrate,

Step 4, see Figure 56, fill in the conductive material at the position where the glass fiber substrate is punched,

Step 5, see Figure 57, coat a layer of copper foil on the front of the glass fiber substrate,

Step 6, see Figure 58, coat the photoresist film on the surface of the glass fiber substrate,

Step 7, see Figure 59, expose and develop the photoresist film at the required position to open the window,

Step 8, see Figure 60, etch the part where the window is opened,

Step 9, see Figure 61, peel off the photoresist film on the surface of the substrate,

Step 10, see Figure 62, apply solder resist paint (commonly known as green paint) on the surface of the copper foil circuit layer,

Step 11. Referring to Figure 63, 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 64, 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 65, 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 purpose of the present invention is to overcome the above disadvantages, to provide a flip-chip single-sided three-dimensional circuit first sealed and then etched manufacturing method and its packaging structure, the process is simple, no need to use glass fiber layer, reducing the manufacturing cost, improving the packaging body The safety and reliability of the circuit reduce the environmental pollution caused by the glass fiber material, 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 flip-chip single-sided three-dimensional circuit first encapsulates and then etch manufacturing method, 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

Electroplate the metal circuit layer on the area where the metal circuit layer pre-treatment is completed on the front side of the metal substrate in step 13. After the metal circuit layer is electroplated, the pins or the base island and the upper part of the pins are relatively formed on the front side of the metal substrate.

Step 16, chip loading and chip bottom filling

Flip chip on the upper side of the pins formed in step 15 and fill the bottom of the chip with epoxy resin,

Step seventeen, encapsulation

Encapsulate the front side of the metal substrate after chip flip-chip and chip underfill in step 16,

Step 18. 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 19. Chemical Etching

Perform chemical etching on the graphic area where the windows are opened on the back of the metal substrate in step 18,

Step 20, electroplating metal circuit layer

Electroplating the metal circuit layer on the surface of the inert metal circuit layer exposed after the chemical etching is completed in step nineteen, after the completion of the electroplating of the metal circuit layer, the pin or base island and the lower part of the pin are relatively formed on the back of the metal substrate,

Step 21, green paint coating

In step 20, the backside of the metal substrate on which the electroplating metal circuit layer is completed is covered with green paint,

Step 22. 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 21, carry out the subsequent drilling work in the area where the metal balls will be planted,

Step twenty-three, cleaning

Clean the opening of the green paint on the back of the metal substrate in step 22

Step twenty-four, planting the ball

Insert a metal ball into the cleaned hole in step 23,

Step 25. Cut the finished product

Cut the semi-finished products that have been ball-planted in step 24, so that the plastic-encapsulated modules that were originally integrated in the form of an array assembly and contain chips are cut and separated one by one, and the flip-chip single-sided three-dimensional circuit is obtained. After sealing, etch the finished package structure.

A packaging structure of a chip flip-chip single-sided three-dimensional circuit first sealing and then etching manufacturing method, which includes a base island, pins and chips, the chip is flip-chip on the base island and the front of the pins, the bottom of the chip is connected to the base island and the An underfill glue is provided between the front faces of the pins, and the area around the base island, the area between the base island and the pins, the area between the pins, and the area under the base island and the pins are encapsulated with Green paint, the area of the base island and the upper part of the pins and the outside of the chip are encapsulated with a plastic compound, the surface of the green paint at the lower part of the pins is provided with small holes, and the small holes communicate with the back of the pins. A metal ball is arranged in the hole, and the metal ball is in contact with the back of the pin.

The step 23 cleans the openings of the green paint on the back of the metal substrate and covers the metal protective layer at the same time.

The packaging structure includes a base island. At this time, the chip is flipped on the base island and the front side of the pins, and an underfill glue is arranged between the bottom of the chip, the front side of the base island, and the front side of the pins.

There are single or multiple base islands. 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

1 to 25 are schematic diagrams of each process in Embodiment 1 of the manufacturing method for flip-chip single-sided three-dimensional circuit of the present invention, which is sealed first and then etched.

Fig. 26 is a structural schematic diagram of Embodiment 1 of the flip-chip single-sided three-dimensional circuit packaging structure of the present invention, which is sealed first and then etched.

27 to 51 are schematic diagrams of each process in Embodiment 2 of the manufacturing method for flip-chip single-sided three-dimensional circuit of the present invention, which is sealed first and then etched.

Fig. 52 is a structural schematic diagram of Embodiment 2 of the flip-chip single-sided three-dimensional circuit packaging structure of the present invention, which is sealed first and then etched.

53 to 64 are schematic diagrams of each process of the manufacturing process flow of the traditional high-density substrate packaging structure.

Fig. 65 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

chip 8

Underfill 9

Plastic compound 10

Small hole 11

Metal protection layer 12

metal ball 13

pin 14

Key Island 15.

Detailed ways

The manufacturing method of the chip flip-chip 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, chip loading and chip bottom filling

Referring to Fig. 16, the chip is flip-chip mounted on the upper side of the oppositely formed pins in step fifteen and the bottom of the chip is filled with epoxy resin;

Step seventeen, encapsulation

Referring to Figure 17, encapsulate the front of the metal substrate after chip flipping and chip bottom filling in step 16. The encapsulation method of the plastic compound can be mold filling, spraying or brushing. The molding compound can be epoxy resin with filler or no filler;

Step 18. Remove part of the green paint on the back of the metal substrate

Referring to Fig. 18, 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 subsequently chemically etched on the back of the metal substrate;

Step 19. Chemical Etching

Referring to Figure 19, perform chemical etching on the graphic area where the window is opened on the back of the metal substrate in step 18, until the position of the inert metal circuit layer is chemically etched, and the etching solution can be copper chloride or ferric chloride;

Step 20, electroplating metal circuit layer

Referring to FIG. 20 , the surface of the inert metal circuit layer exposed after the chemical etching in step nineteen 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 can be It is 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, and the electroplating method can be chemical electroplating or electrolytic electroplating;

Step 21, green paint coating

Referring to FIG. 21 , in step 20, the backside of the metal substrate of the electroplated metal circuit layer is covered with green paint;

Step 22. Open holes on the surface of the green paint

Referring to FIG. 22 , in step 21, 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-three, cleaning

Referring to Figure 23, clean the opening of the green paint on the back of the metal substrate in step 22 to remove oxidized substances or organic substances, and at the same time coat the metal protective layer, which uses an antioxidant;

Step twenty-four, planting the ball

Referring to Figure 24, metal balls are implanted in the cleaned small holes in step 23, 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 25. Cut the finished product

Referring to Figure 25, the semi-finished product that has completed the ball planting in step 24 is cut, so that the plastic package modules that are originally integrated in an array assembly and contain chips are cut and separated one by one, and the chip flip chip is obtained. The surface 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. 26, the chip flip-chip single-sided three-dimensional circuit packaging structure of the present invention is first sealed and then etched. It includes pins 14 and chips 8. The chip 8 is flip-chip on the front of the pins 14, and the bottom of the chip 8 is connected to the pins 14. Underfill glue 9 is provided between the fronts, the area around the pins 14, the area between the pins 14 and the pins 14, and the area below the pins 14 are encapsulated with green paint 3, the upper part of the pins 14 The area and the chip 8 are encapsulated with a plastic encapsulant 10, and a small hole 11 is opened on the surface of the green paint 3 at the bottom of the pin 14, and the small hole 11 communicates with the back of the pin 14, and the small hole 11 is set There is a metal ball 13, the metal ball 13 is in contact with the back of the pin 14, and a metal protective layer 12 is arranged between the metal ball 13 and the back of the pin 14, and the metal protective layer 12 is an antioxidant.

Embodiment 2, there is base island

Step 1. Take the metal substrate

Referring to Figure 27, 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 28, 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 29, 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 Fig. 30, 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. 31 , electroplating an inert metal circuit layer on the graphic area of the front of the metal substrate in step 4 where windows have 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. 32, 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. 33 , 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 34, 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 Figure 35, 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. 36 , 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. 37, 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 Figure 38, the front of the metal substrate is covered with a circuit screen, and the circuit screen covers the area that does not need to be metallized in the future;

Step 13, pre-metallization treatment

Referring to Figure 39, perform metallization pre-treatment on the pattern area of the metal substrate on which 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, shower coating or immersion, etc. Way;

Step 14. Remove the circuit board

Referring to Figure 40, 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. 41 , the metal circuit layer is electroplated on the area where the metal circuit layer pretreatment is completed on the front of the metal substrate in step 13. After the metal circuit layer is electroplated, the base island or the upper part of the pin is 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, chip loading and chip bottom filling

Referring to FIG. 42 , in step 15, the base island and the upper part of the pins are oppositely formed to flip-chip the chip and fill the bottom of the chip with epoxy resin;

Step seventeen, encapsulation

Referring to Figure 43, encapsulate the front of the metal substrate after chip flip-chip and chip bottom filling in Step 16. The encapsulation method of the plastic compound can be mold filling, spraying or brushing. The molding compound can be epoxy resin with filler or no filler;

Step 18. Remove part of the green paint on the back of the metal substrate

Referring to Fig. 44, 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 subsequently chemically etched on the back of the metal substrate;

Step 19. Chemical Etching

Referring to Figure 45, chemically etch the graphic area where the window is opened on the back of the metal substrate in step 18 until the position of the inert metal circuit layer is chemically etched. The etching solution can be copper chloride or ferric chloride;

Step 20, electroplating metal circuit layer

Referring to FIG. 46, the surface of the inert metal circuit layer exposed after the chemical etching in step nineteen is subjected to electroplating of the metal circuit layer. After the electroplating of the metal circuit layer is completed, the base island or the lower part of the pin is relatively formed on the back of the metal substrate. The 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 21, green paint coating

Referring to FIG. 47 , in step 20, the backside of the metal substrate on which the electroplated metal circuit layer is completed is coated with green paint;

Step 22. Open holes on the surface of the green paint

Referring to Fig. 48, on the surface of the green paint coated on the back of the metal substrate in step 21, the subsequent opening operation of the area to be planted with metal balls is performed. The opening method can be dry laser sintering or wet chemical etching;

Step twenty-three, cleaning

Referring to Figure 49, clean the openings of the green paint on the back of the metal substrate in step 22 to remove oxidized substances or organic substances, etc., and at the same time coat the metal protective layer, which uses an antioxidant;

Step twenty-four, planting the ball

Referring to Figure 50, metal balls are implanted in the cleaned holes in step 23, 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 25. Cut the finished product

Referring to Figure 51, the semi-finished products that have been ball-planted in step 24 are 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 chip flip chip is obtained. The surface 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. 52, the chip flip-chip single-sided three-dimensional circuit packaging structure of the present invention is first sealed and then etched, which includes a base island 15, pins 14 and chips 8, and the chip 8 is flip-chip on the front of the base island 15 and pins 14, so Underfill glue 9 is provided between the bottom of the chip 8 and the front of the base island 15 and the pin 14, the area around the base island 15, the area between the base island 15 and the pin 14, the pin 14 and the pin 14 The area between the base island 15 and the lower part of the pin 14 is encapsulated with green paint 3, the area on the base island 15 and the upper part of the pin 14 and the chip 8 are encapsulated with a plastic encapsulant 10, and the lower part of the pin 14 A small hole 11 is provided on the surface of the green paint 3, and the small hole 11 communicates with the back of the pin 14, and a metal ball 13 is arranged in the small hole 11, and the metal ball 13 is in contact with the back of the pin 14, A metal protection layer 12 is provided between the metal ball 13 and the back of the pin 14, and the metal protection layer 12 is an antioxidant.

Claims (5)

1. the three-dimensional circuit of the flip-chip single face erosion manufacturing approach of being honored as a queen earlier is characterized in that said method comprises following processing step:

Step 1, get metal substrate

Step 2, metallic substrate surfaces preplating copper material

Electroplate one deck copper material film in metallic substrate surfaces,

Step 3, green lacquer coating

Accomplish the metal substrate front and the back side of preplating copper material film in step 2 and carry out the lining of green lacquer,

Step 4, the positive green lacquer of part of removing of metal substrate

Utilize exposure imaging equipment to carry out graph exposure, develop and window, to expose the graphics field that the positive follow-up needs of metal substrate are electroplated in the metal substrate front that step 3 is accomplished green lacquer coating;

Step 5, plating inert metal line layer

The graphics field of windowing has been accomplished in step 4 metal substrate front has electroplated upward inert metal line layer,

Step 6, plated metal line layer

Inert metal line layer surface metal plated line layer in step 5,

Step 7, green lacquer coating

Accomplish the metal substrate front of plated metal line layer in step 6 and carry out the lining of green lacquer once more,

Step 8, the positive green lacquer of part of removing of metal substrate

Utilize exposure imaging equipment to carry out graph exposure, develop and window in the metal substrate front that step 7 is accomplished green lacquer coating, exposing the graphics field that the positive follow-up needs of metal substrate are electroplated,

Step 9, plated metal line layer

The graphics field of windowing has been accomplished in step 8 metal substrate front has electroplated upward metallic circuit layer,

Step 10, green lacquer coating

Accomplish the metal substrate front of plated metal line layer in step 9 and carry out the lining of green lacquer once more,

Step 11, the positive green lacquer of part of removing of metal substrate

Utilize exposure imaging equipment to carry out graph exposure, develop and window in the metal substrate front that step 10 is accomplished green lacquer coating, exposing the graphics field that the positive follow-up needs of metal substrate are electroplated,

Step 12, be covered with the circuit web plate

Be covered with the circuit web plate in the metal substrate front,

Step 13, metallization pre-treatment

The metallization pre-treatment that the plated metal line layer is carried out in the graphics field of windowing has been accomplished in step 11 metal substrate front,

Step 14, remove the circuit web plate

The circuit web plate that metal substrate front in the step 12 is covered with removes,

Step 15, plated metal line layer

The positive zone of accomplishing the pre-treatment of plated metal line layer of step 13 metal substrate electroplated goes up the metallic circuit layer, after said metallic circuit layer is electroplated and is accomplished promptly on the positive top that forms pin or Ji Dao and pin relatively of metal substrate,

Step 10 six, load and chip bottom are filled

Chip and chip bottom filling epoxy resin in the top front face upside-down mounting of relative Ji Dao that forms of step 15 or pin,

Step 10 seven, seal

The plastic packaging material operation is sealed in metal substrate front after step 10 six completion flip-chip and the chip bottom filling,

The green lacquer of part is removed at step 10 eight, the metal substrate back side

Utilize exposure imaging equipment that the green lacquer of metal substrate back side coating is carried out graph exposure, develops and windows, exposing the graphics field that the follow-up needs in the metal substrate back side carry out chemical etching,

Step 10 nine, chemical etching

The graphics field of windowing is accomplished at the metal substrate back side in the step 10 eight carries out chemical etching,

Step 2 ten, plated metal line layer

Accomplish the inert metal line layer surface of exposing after the chemical etching in step 10 nine and carry out the plating of metallic circuit layer, promptly form the bottom of pin or Ji Dao and pin after the metallic circuit layer is electroplated and accomplished relatively at the metal substrate back side,

Step 2 11, green lacquer coating

The lining of green lacquer is carried out at the metal substrate back side in that step 2 ten is accomplished the plated metal line layer,

Step 2 12, the surperficial perforate of green lacquer

The follow-up perforate operation that will plant the metal ball zone is carried out on green lacquer surface in step 2 11 metal substrate back side coatings,

Step 2 13, cleaning

The green lacquer tapping in the step 2 12 metal substrate back sides is cleaned

Step 2 14, plant ball

The aperture of crossing cleaning at the step 2 Thirteen Classics is implanted into metal ball,

Step 2 15, cutting finished product

Step 2 14 is accomplished the semi-finished product of planting ball carry out cutting operation; Make originally to integrate and to contain more than cuttings of plastic-sealed body module of chip independent, make the three-dimensional circuit of flip-chip single face and be honored as a queen earlier and lose the encapsulating structure finished product with array aggregate mode.

2. be honored as a queen earlier encapsulating structure of erosion manufacturing approach of the three-dimensional circuit of flip-chip single face according to claim 1; It is characterized in that: it comprises Ji Dao (15), pin (14) and chip (8); Said chip (8) upside-down mounting is in Ji Dao (15) and pin (14) front; Be provided with underfill (9) between said chip (8) bottom and Ji Dao (15) and pin (14) front; The zone between zone, pin (14) and the pin (14) between zone, Ji Dao (15) and the pin (14) of said Ji Dao (15) periphery and the zone of Ji Dao (15) and pin (14) bottom are encapsulated with green lacquer (3); The outer plastic packaging material (10) that is encapsulated with of the zone on said Ji Dao (15) and pin (14) top and chip (8); Offer aperture (11) on green lacquer (3) surface of said pin (14) bottom; Said aperture (11) is connected with pin (14) back side, is provided with metal ball (13) in the said aperture (11), and said metal ball (13) contacts with pin (14) back side.

3. the three-dimensional circuit of a kind of flip-chip single face according to claim 1 erosion manufacturing approach of being honored as a queen earlier, it is characterized in that: the green lacquer tapping in 13 pairs of metal substrate back sides of said step 2 cleans and carries out the coat of metal lining simultaneously.

4. the three-dimensional circuit of a kind of flip-chip single face according to claim 2 is honored as a queen earlier and is lost the encapsulating structure of manufacturing approach; It is characterized in that: said encapsulating structure comprises Ji Dao (15); This moment, chip (8) upside-down mounting Ji Dao (15) and pin (14) front were provided with underfill (9) between said chip (8) bottom and Ji Dao (15) front and pin (14) front.

5. the three-dimensional circuit of a kind of flip-chip single face according to claim 4 is honored as a queen earlier and is lost the encapsulating structure of manufacturing approach, and it is characterized in that: said Ji Dao (15) has single or a plurality of.

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