A direct co-crystal type chip packaging structure

Abstract

The application discloses a kind of direct eutectic chip packaging structures, including semiconductor chip and ceramic tube shell, the semiconductor chip includes chip body, chip back metallization layer and chip front metallization layer, the chip body lower surface is provided with chip back metallization layer, the ceramic tube shell eutectic welding in chip back metallization layer bottom, the ceramic tube shell includes tube shell surface layer gold plating layer, tube shell surface layer secondary gold plating layer, tube shell tungsten slurry layer and tube shell ceramic body.This direct eutectic chip packaging structure, chip back metallization layer and tube shell surface layer gold plating layer are heated after high temperature, after friction direct eutectic welding, realize chip and tube shell direct effective connection, direct eutectic welding is conducive to enhancing connection firmness, reduce resistance impedance, improve current flow and heat dissipation capacity, and do not need to use alloy solder, it is favorable to reduce operation difficulty, to improve production efficiency and improve qualified product rate, strong practicality is convenient for popularization and use.

Description

Technical Field

[0001] This invention relates to the field of semiconductor devices and integrated circuit technology, specifically to a direct eutectic chip packaging structure. Background Technology

[0002] Packaging plays a vital role in semiconductor chips and other integrated circuits. The casing used to mount semiconductor integrated circuit chips serves to house, fix, seal, protect the chips, and enhance their electrothermal performance.

[0003] Traditional chip packaging typically uses indirect eutectic chip packaging structures, where the chip is bonded to the ceramic casing using gold-silicon solder, gold-tin solder, or gold-gallium solder for indirect eutectic bonding. This method has the following main drawbacks:

[0004] 1. Alloy solder is used to weld the chip to the ceramic housing, which increases the welding distance between the chip and the ceramic housing, resulting in high electrical resistance, greater current limitation, and increased thermal resistance.

[0005] 2. When using alloy solder for welding, the operator needs to place the chip and alloy solder pad simultaneously on the metallized layer of the ceramic casing and apply high temperature and friction. The disadvantages are: high precision is required, the operation is difficult, the production efficiency is low, and the defect rate is high. Summary of the Invention

[0006] The purpose of this invention is to provide a direct eutectic chip packaging structure to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a direct eutectic chip packaging structure, comprising a semiconductor chip and a ceramic casing, wherein the semiconductor chip comprises a chip body, a back metallization layer and a front metallization layer, the back metallization layer is disposed on the lower surface of the chip body, and the front metallization layer is disposed on the upper surface of the chip body, the ceramic casing is eutecticly bonded to the bottom of the back metallization layer of the chip, the ceramic casing comprises a surface gold plating layer, a surface gold plating layer, a tungsten paste layer and a ceramic body, the bottom of the inner wall of the ceramic body is disposed of a tungsten paste layer, the upper surface of the tungsten paste layer is disposed of a surface gold plating layer, and the surface of the surface gold plating layer is disposed of a surface gold plating layer.

[0008] Furthermore, the gold plating layer on the surface of the casing is eutectic welded to the metallization layer on the back of the chip, and the thickness of the metallization layer on the back of the chip is 2µm.

[0009] Furthermore, the thickness of the gold plating layer on the surface of the tube shell is 2µm, and the thickness of the gold plating layer on the surface of the tube shell is 6µm.

[0010] Furthermore, a fixing groove is provided at one corner of the surface of the ceramic body of the tube shell, and a retaining groove is provided at the other triangular parts of the surface of the ceramic body of the tube shell.

[0011] Furthermore, a connecting column is fixed inside the fixing groove, and a ceramic sealing plate is rotatably connected to the top of the connecting column.

[0012] Furthermore, the ceramic sealing plate, except for the connecting post, has ball-concealing grooves inside the other triangular sections, and iron balls are placed inside the ball-concealing grooves.

[0013] Furthermore, the outer diameter of the iron ball is larger than the bottom inner diameter of the ball storage groove, and the bottom of the iron ball protrudes from the bottom of the ceramic sealing plate.

[0014] Furthermore, a magnet is provided at the bottom of the inner wall of the slot, and the vertical central axis of the slot coincides with the vertical central axis of the ball storage groove.

[0015] This invention provides a direct eutectic chip packaging structure, which has the following advantages:

[0016] 1. In this invention, the metallized layer on the back of the chip at the bottom of the chip body and the gold-plated layer on the surface of the ceramic body of the casing are directly eutectic welded by friction after being heated at high temperature, so as to achieve a direct and effective connection between the chip and the casing. Direct eutectic welding is beneficial to enhance the connection strength, reduce the impedance rate, increase the current and heat dissipation capacity, and does not require the use of alloy solder, which helps to reduce the difficulty of operation, thereby improving production efficiency and the yield rate. It is highly practical and easy to promote and use.

[0017] 2. In this invention, the ceramic sealing plate is manually pushed to rotate through the connecting column while rotating against the surface of the ceramic body of the tube shell until the ceramic sealing plate and the ceramic body of the tube shell are aligned. At this time, the bottom of the iron ball protrudes from the bottom of the ceramic sealing plate and is locked into the slot. The locking effect between the iron ball and the slot is strengthened by a magnet, thereby improving the firmness of the ceramic sealing plate after it is aligned with the ceramic body of the tube shell and preventing the ceramic sealing plate from rotating randomly.

[0018] 3. In the later stages of this invention, the iron ball can be disengaged from the magnetic attraction by forcefully pushing the ceramic sealing plate, so that the ceramic sealing plate can rotate and expose the inside of the ceramic body of the tube shell, so that the chip body can be inspected and repaired later. Attached Figure Description

[0019] Figure 1 This is a schematic cross-sectional view of the chip body structure of a direct eutectic chip packaging structure according to the present invention;

[0020] Figure 2 This is a schematic cross-sectional view of the ceramic body of the direct eutectic chip packaging structure according to the present invention.

[0021] Figure 3This is a top view schematic diagram of a ceramic sealing plate for a direct eutectic chip packaging structure according to the present invention;

[0022] Figure 4 This invention provides a direct eutectic chip packaging structure. Figure 2 Enlarged structural diagram at point A in the middle.

[0023] In the diagram: 1. Semiconductor chip; 101. Chip body; 102. Back metallization layer of chip; 103. Front metallization layer of chip; 2. Ceramic casing; 201. Gold plating layer on the surface of casing; 202. Gold plating layer on the surface of casing; 203. Tungsten paste layer on casing; 204. Ceramic body of casing; 3. Fixing groove; 4. Card slot; 5. Connecting post; 6. Ceramic sealing plate; 7. Ball storage groove; 8. Iron ball; 9. Magnet. Detailed Implementation

[0024] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0025] like Figure 1 A direct eutectic chip packaging structure includes a semiconductor chip 1 and a ceramic shell 2. The semiconductor chip 1 includes a chip body 101, a back metallization layer 102, and a front metallization layer 103. The back metallization layer 102 is disposed on the lower surface of the chip body 101, and the front metallization layer 103 is disposed on the upper surface of the chip body 101. The ceramic shell 2 is eutectic bonded to the bottom of the back metallization layer 102. The ceramic shell 2 includes a surface gold plating layer 201, a surface gold plating layer 202, and a tungsten paste. The material layer 203 and the ceramic body 204 of the tube shell are provided. The bottom of the inner wall of the ceramic body 204 of the tube shell is provided with a tungsten paste material layer 203, and the upper surface of the tungsten paste material layer 203 is provided with a surface gold plating layer 202. The surface of the surface gold plating layer 202 is provided with a surface gold plating layer 201. The surface gold plating layer 201 is eutectic welded to the back metallization layer 102 of the chip. The back metallization layer 102 of the chip has a thickness of 2µm, the surface gold plating layer 201 has a thickness of 2µm, and the surface gold plating layer 202 has a thickness of 6µm.

[0026] The specific operation is as follows: After a metal evaporation process, an Al layer (i.e., the front metallization layer 103) is evaporated on the upper surface of the chip body 101, and an Au layer (i.e., the back metallization layer 102) is evaporated on the lower surface of the chip body 101. The thickness of the back metallization layer 102 is controlled between 1.5-3 μm. The ceramic body 204 of the casing is made of Al2O3 material. Tungsten paste is coated on the surface of the ceramic body 204 to form a tungsten paste layer 203. Then, a layer is applied to the surface of the tungsten paste layer 203... A Ne layer with a thickness of 3-9 μm is electroplated, which is the gold plating layer 202 on the surface of the casing. Then, an Au layer is electroplated on the surface of the gold plating layer 202, which is the gold plating layer 201 on the surface of the casing. The thickness of the gold plating layer 201 on the surface of the casing is 1.5-3 μm. Then, the back metallization layer 102 of the chip body 101 at the bottom of the chip body 101 and the gold plating layer 201 on the surface of the casing ceramic body 204 are directly eutectic bonded by friction after high temperature heating, so as to achieve a direct and effective connection between the chip and the casing.

[0027] like Figure 2-4 As shown, a fixing groove 3 is provided at one corner of the surface of the ceramic body 204 of the tube shell, and a slot 4 is provided at the other triangular parts of the surface of the ceramic body 204 of the tube shell. A connecting column 5 is fixed inside the fixing groove 3, and a ceramic sealing plate 6 is rotatably connected to the top of the connecting column 5. A ball-holding groove 7 is provided inside the other triangular parts of the ceramic sealing plate 6 except for the connecting column 5, and an iron ball 8 is placed inside the ball-holding groove 7. The outer diameter of the iron ball 8 is larger than the bottom inner diameter of the ball-holding groove 7, and the bottom of the iron ball 8 protrudes from the bottom of the ceramic sealing plate 6. A magnet 9 is provided at the bottom of the inner wall of the slot 4, and the vertical central axis of the slot 4 coincides with the vertical central axis of the ball-holding groove 7.

[0028] The specific operation is as follows: After the chip body 101 and the ceramic body 204 of the casing are eutectic welded, the ceramic sealing plate 6 is manually pushed so that it rotates through the connecting post 5 and is attached to the surface of the ceramic body 204 of the casing until the ceramic sealing plate 6 and the ceramic body 204 of the casing are overlapped. During this process, the iron ball 8 is at the bottom of the ball storage groove 7 due to gravity and rolls against the surface of the ceramic body 204 of the casing. After the ceramic sealing plate 6 and the ceramic body 204 of the casing are overlapped, the bottom of the iron ball 8 passes through the bottom of the ball storage groove 7 and protrudes from the bottom of the ceramic sealing plate 6 and is stuck in the slot 4. The locking effect between the iron ball 8 and the slot 4 is strengthened by the magnet 9, thereby improving the firmness of the overlap between the ceramic sealing plate 6 and the ceramic body 204 of the casing and preventing the ceramic sealing plate 6 from rotating at will. Later, the iron ball 8 can be removed from the magnetic attraction by pushing the ceramic sealing plate 6, so that the ceramic sealing plate 6 can rotate to expose the inside of the ceramic body 204 of the casing for later inspection of the chip body 101.

[0029] In summary, as Figure 1-4As shown, in use, this direct eutectic chip packaging structure first undergoes a metal evaporation process. An Al layer, i.e., the front metallization layer 103, is evaporated on the upper surface of the chip body 101, and an Au layer, i.e., the back metallization layer 102, is evaporated on the lower surface of the chip body 101. The thickness of the back metallization layer 102 is controlled at 1.5-3 μm. The ceramic body 204 of the casing is made of Al2O3 material. A tungsten paste is coated on the surface of the ceramic body 204 to form a tungsten paste layer 203. Then, a Ne layer with a thickness of 3-9 μm is electroplated on the surface of the tungsten paste layer 203, i.e., a gold plating layer 202 on the surface of the casing. Finally, an Au layer is electroplated on the surface of the gold plating layer 202, i.e., a gold plating layer 201 on the surface of the casing. The thickness of the gold plating layer 201 is 1.5-3 μm.

[0030] Then, the back metallization layer 102 of the chip body 101 at the bottom and the gold plating layer 201 of the ceramic body 204 are directly eutectic welded by friction after being heated at high temperature, so as to achieve a direct and effective connection between the chip and the shell.

[0031] After the chip body 101 and the ceramic body 204 of the casing are eutectic welded, the ceramic sealing plate 6 is manually pushed to rotate through the connecting post 5 and rotate against the surface of the ceramic body 204 of the casing until the ceramic sealing plate 6 and the ceramic body 204 of the casing are overlapped. During this process, the iron ball 8 is at the bottom of the ball storage groove 7 due to gravity and rolls against the surface of the ceramic body 204 of the casing. After the ceramic sealing plate 6 and the ceramic body 204 of the casing are overlapped, the bottom of the iron ball 8 passes through the bottom of the ball storage groove 7 and protrudes from the bottom of the ceramic sealing plate 6 and is stuck in the slot 4. The locking effect between the iron ball 8 and the slot 4 is strengthened by the magnet 9, thereby improving the firmness of the ceramic sealing plate 6 and the ceramic body 204 of the casing after overlap and preventing the ceramic sealing plate 6 from rotating at will.

[0032] Later, the ceramic sealing plate 6 can be pushed forcefully to disengage the iron ball 8 from the magnetic attraction, causing the ceramic sealing plate 6 to rotate, so as to expose the inside of the ceramic body 204 of the tube shell, so as to carry out the inspection of the chip body 101 later.

[0033] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A direct eutectic chip packaging structure, comprising a semiconductor chip (1) and a ceramic housing (2), characterized in that: The semiconductor chip (1) includes a chip body (101), a back metallization layer (102), and a front metallization layer (103). The back metallization layer (102) is disposed on the lower surface of the chip body (101), and the front metallization layer (103) is disposed on the upper surface of the chip body (101). The ceramic shell (2) is eutectic bonded to the bottom of the back metallization layer (102). The ceramic shell (2) includes a shell surface gold plating layer (201), a shell surface gold plating layer (202), a shell tungsten paste layer (203), and a shell ceramic body (204). The inner wall bottom of the shell ceramic body (204) is provided with a shell tungsten paste layer (203), and the upper surface of the shell tungsten paste layer (203) is provided with a shell surface gold plating layer (202). The surface of the shell surface gold plating layer (202) is provided with a shell surface gold plating layer (201). A fixing groove (3) is provided at one corner of the surface of the ceramic body (204) of the tube shell, and a slot (4) is provided at the other triangular parts of the surface of the ceramic body (204); A connecting column (5) is fixed inside the fixing groove (3), and a ceramic sealing plate (6) is rotatably connected to the top of the connecting column (5); Except for the connecting post (5), the ceramic sealing plate (6) has ball-concealing grooves (7) inside the other triangular parts, and iron balls (8) are placed inside the ball-concealing grooves (7); The bottom of the inner wall of the slot (4) is provided with a magnet (9), and the vertical central axis of the slot (4) coincides with the vertical central axis of the ball storage groove (7).

2. The direct eutectic chip packaging structure according to claim 1, characterized in that, The gold plating layer (201) on the surface of the casing is eutectic welded to the metallization layer (102) on the back of the chip, and the thickness of the metallization layer (102) on the back of the chip is 2um.

3. The direct eutectic chip packaging structure according to claim 1, characterized in that, The thickness of the gold plating layer (201) on the surface of the tube shell is 2 μm, and the thickness of the gold plating layer (202) on the surface of the tube shell is 6 μm.

4. The direct eutectic chip packaging structure according to claim 1, characterized in that, The outer diameter of the iron ball (8) is larger than the bottom inner diameter of the ball storage groove (7), and the bottom of the iron ball (8) protrudes from the bottom of the ceramic sealing plate (6).

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