Three-dimensional airtight packaging structure and packaging method

Abstract

The invention discloses a three-dimensional airtight packaging structure and a packaging method, and belongs to the technical field of microelectronic packaging, the three-dimensional airtight packaging structure comprises a bottom packaging substrate, a top packaging substrate and a side wall arranged on the bottom packaging substrate, and is characterized in that a frame-shaped sealing material layer is arranged between the top packaging substrate and the bottom packaging substrate; the top of the side wall is provided with a frame-shaped groove, the side wall, facing the side wall, of the top packaging substrate is provided with a protruding strip matched with the groove, the bottom packaging substrate is provided with a chip module, and the side wall and the top packaging substrate are integrated in an airtight mode in an airtight welding mode to form the airtight packaging structure. The airtight packaging structure is placed in a welding cabin for welding work; through splicing of the grooves and the protruding strips, the connecting accuracy is guaranteed, the connecting efficiency is also guaranteed, welding sealing is conducted in a laser welding mode, the welding quality is guaranteed, and the product airtightness is good.

Description

Technical Field

[0001] The present invention relates to the technical field of microelectronic packaging, and in particular to a three-dimensional airtight packaging structure and a packaging method. Background Art

[0002] Miniaturization, multifunctionality and high performance are important directions for the development of electronic systems. Three-dimensional integration technology based on system-level packaging (SiP) is an important way to achieve miniaturization and multifunctionality of electronic systems. This technology emphasizes the use of adapter plates and packaging substrates to achieve chip stacking in three dimensions, integrating multiple chips, devices and passive components in one package to achieve higher overall integration density. Among them, ceramic packaged SiP has the characteristics of high integration and airtightness, and is the most widely used high-reliability packaging structure. However, the signal interconnection interfaces of traditional ceramic packaged SiP are concentrated on the bottom surface, which cannot meet the requirements of high-density and low-loss transmission of signals in the vertical direction of the RF array, limiting the improvement of system integration density.

[0003] The purpose of packaging power electronic devices is to isolate the chip from external environments such as temperature, humidity, and air. It provides protection and electrical insulation, and can also dissipate heat and release stress. The current packaging method is to directly weld and seal the top packaging substrate and the side wall. However, due to operational deviations, this method cannot guarantee the accuracy of the connection between the top packaging substrate and the side wall, affecting the packaging effect. Summary of the invention

[0004] The purpose of the present invention is to provide a three-dimensional airtight packaging structure and packaging method to solve the following technical problems: The current packaging method is to directly weld and seal the top packaging substrate and the side wall, but due to operational deviations, this method cannot guarantee the accuracy of the connection between the top packaging substrate and the side wall, affecting the packaging effect.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A three-dimensional airtight packaging structure, comprising a bottom packaging substrate, a top packaging substrate and a side wall arranged on the bottom packaging substrate, characterized in that a frame-shaped sealing material layer is arranged between the top packaging substrate and the bottom packaging substrate, a frame-shaped groove is opened on the top of the side wall, a convex strip matching the groove is arranged on the side wall of the top packaging substrate facing the side wall, a chip module is arranged on the bottom packaging substrate, and the side wall and the top packaging substrate are airtightly integrated by airtight welding to form an airtight packaging structure; The airtight packaging structure is placed in the welding cabin for welding work.

[0006] As a further solution of the present invention: a sink with an arc-shaped cross-section is provided at the bottom of the groove, and hot-melt adhesive strips are provided on both sides of the sink.

[0007] As a further solution of the present invention: an arched protrusion is connected between the hot melt adhesive strips on both sides.

[0008] As a further solution of the present invention: two slide grooves are provided on the inner walls on both sides of the welding chamber, and a pressure mechanism is slidably connected between the slide grooves on both sides, and the pressure mechanism includes two mounting plates, and sliders are fixed on the side walls of the two mounting plates that are far away from each other, and the sliders are slidably connected to the slide grooves, and two fixed columns are fixed on the side walls of the two mounting plates that are close to each other, and two rotating sleeves are rotatably installed on the fixed columns, a torsion spring is connected between the rotating sleeve and the mounting plate, a mounting frame is fixed to the rotating sleeve, and a pressure wheel is installed at one end of the mounting frame.

[0009] As a further solution of the present invention: it also includes a driving source for driving the pressure mechanism to rise and fall.

[0010] As a further solution of the present invention: the pressure-applying mechanism is provided with a cooling mechanism, and the cooling mechanism includes an air intake box and an annular tube fixed on the mounting plate, the air intake box is connected to an air intake pipe, the two side walls of the air intake box are connected to a first air outlet pipe, and the other two side walls are connected to a second air outlet pipe, the first air outlet pipe and the second air outlet pipe are connected to the annular tube at one end away from the air intake box, and the side wall of the annular tube facing the air intake box is evenly connected with air outlet heads, a slot is provided on the mounting plate, a block matching the slot is fixed on the side wall of the air intake box, and the second air outlet pipe is a spring tube.

[0011] As a further solution of the present invention: two piston plates are movably arranged in the air intake box, one end of two first air outlet pipes extends into the air intake box and is connected to the piston plate, and the first air outlet pipes penetrate the piston plate, a horizontal plate is fixed in the air intake box, the horizontal plate is located between the two piston plates, a cooling source is arranged below the horizontal plate, and springs are connected to the side walls of the two piston plates away from each other.

[0012] As a further solution of the present invention: the cooling source is ice cubes.

[0013] A packaging method for a three-dimensional airtight packaging structure comprises the following steps: S1. Place a sealing material layer on top of the side wall; S2, splicing the convex strip at the bottom of the top packaging substrate with the groove at the top of the side wall; S3, welding is performed in the welding chamber to form an airtight packaging structure, and a pressure mechanism is used to apply pressure to the top packaging substrate during welding; S4. After welding is completed, the welding point is cooled by a cooling mechanism.

[0014] Beneficial effects of the present invention: (1) The present invention realizes precise alignment between the top package substrate and the side wall by providing grooves and convex strips, thereby improving the installation accuracy. The splicing of the grooves and convex strips ensures both the accuracy and efficiency of the connection. Then, laser welding is used for welding and sealing, thereby ensuring the welding quality and good air tightness. (2) The present invention provides a sink groove, a hot melt adhesive strip and an arched protrusion. When the top packaging substrate is connected to the side wall, the convex strip will squeeze the arched protrusion, so that the hot melt adhesive strips on both sides move. The hot melt adhesive strips are close to the connection between the convex strip and the sink groove. After being heated during welding, the hot melt adhesive strips melt, further improving the sealing effect. (3) The present invention provides a pressure mechanism and a cooling mechanism. During the welding process, the pressure mechanism applies an appropriate amount of pressure to the top package to ensure the welding effect. The cooling mechanism is used to cool the welding point to reduce the possibility of welding stress and deformation, thereby ensuring product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below in conjunction with the accompanying drawings.

[0016] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is a schematic diagram of the three-dimensional structure of the side wall of the present invention; Figure 3 It is a structural schematic diagram of the convex strip of the present invention; Figure 4 is a cross-sectional view of the side wall of the present invention; Figure 5 yes Figure 4 The enlarged view of point A in the middle; Figure 6 It is a schematic diagram of the structure of the hot melt adhesive strip and the arched protrusion of the present invention; Figure 7 It is a structural schematic diagram of the welding cabin of the present invention; Figure 8 It is a schematic diagram of the internal structure of the welding cabin of the present invention; Fig. 9 It is a structural schematic diagram of the pressure applying mechanism of the present invention; Fig.10 It is a structural schematic diagram of the cooling mechanism of the present invention; Fig.11 It is a schematic diagram of the internal structure of the air intake box of the present invention.

[0017] In the figure: 1. bottom packaging substrate; 2. top packaging substrate; 3. side wall; 4. sealing material layer; 5. groove; 6. convex strip; 7. sink groove; 8. hot melt adhesive strip; 9. arched protrusion; 10. welding chamber; 11. slide groove; 12. pressure mechanism; 1201. mounting plate; 1202. slider; 1203. fixing column; 1204. rotating sleeve; 1205. torsion spring; 1206. mounting frame; 1207. pressure wheel; 1208. slot; 13. cooling mechanism; 1301. air inlet box; 1302. annular tube; 1303. block; 1304. first air outlet pipe; 1305. second air outlet pipe; 1306. air outlet head; 1307. air inlet pipe; 1308. piston plate; 1309. horizontal plate; 1310. cooling source; 1311. spring.

[0018] The drawings are only used for illustrative purposes and should not be construed as limitations on this patent. In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged, or reduced, and do not represent the size and shape of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1-6As shown, the present invention is a three-dimensional airtight packaging structure, comprising a bottom packaging substrate 1, a top packaging substrate 2 and a side wall 3 arranged on the bottom packaging substrate 1, characterized in that a frame-shaped sealing material layer 4 is arranged between the top packaging substrate 2 and the bottom packaging substrate 1, a frame-shaped groove 5 is opened on the top of the side wall 3, a convex strip 6 matching the groove 5 is arranged on the side wall of the top packaging substrate 2 facing the side wall 3, a chip module is arranged on the bottom packaging substrate 1, and the side wall 3 and the top packaging substrate 2 are airtightly integrated to form an airtight packaging structure by airtight welding; the airtight packaging structure is placed in a welding cabin 10 for welding, and the groove 5 is A groove 7 with an arc-shaped cross-section is provided at the bottom, and hot-melt adhesive strips 8 are provided on both sides of the groove 7, and an arched protrusion 9 is connected between the hot-melt adhesive strips 8 on both sides; the groove 5 and the convex strip 6 realize the precise alignment of the top packaging substrate 2 and the side wall 3, and improve the installation accuracy. Through the splicing of the groove 5 and the convex strip 6, both the accuracy and efficiency of the connection are guaranteed, and then laser welding is used for welding and sealing, which ensures the welding quality and good air tightness. At the same time, the convex strip 6 will squeeze the arched protrusion 9 to move the hot-melt adhesive strips 8 on both sides, and the hot-melt adhesive strips 8 are close to the connection between the convex strip 6 and the groove 7. After the welding is heated, the hot-melt adhesive strip 8 melts, further improving the sealing effect.

[0021] See also Figure 7-9 Two slide grooves 11 are provided on the inner walls of both sides of the welding chamber 10, and a pressure mechanism 12 is slidably connected between the slide grooves 11 on both sides. The pressure mechanism 12 includes two mounting plates 1201, and sliders 1202 are fixed on the side walls away from each other of the two mounting plates 1201, and the sliders 1202 are slidably connected with the slide grooves 11, and two fixed columns 1203 are fixed on the side walls close to each other of the two mounting plates 1201, and two rotating sleeves 1204 are rotatably installed on the fixed columns 1203. A torsion spring 1205 is connected between the rotating sleeve 1204 and the mounting plate 1201, and a mounting frame 1206 is fixed to the rotating sleeve 1204. A pressure wheel 1207 is installed at one end of the mounting frame 1206. It also includes a driving source, and the output shaft of the driving source is connected to the slider 1202, which is used to drive the pressure mechanism 12 to rise and fall; during welding, the driving source is used to drive the slider 1202 to descend, so that the pressure wheel 1207 contacts the top packaging substrate 2, and applies appropriate pressure to it to ensure the welding effect.

[0022] See also Figure 8-11The pressure mechanism 12 is provided with a cooling mechanism 13, which includes an air intake box 1301 and an annular tube 1302 fixed on the mounting plate 1201. The air intake box 1301 is connected with an air intake pipe 1307. The two side walls of the air intake box 1301 are connected with a first air outlet pipe 1304, and the other two side walls are connected with a second air outlet pipe 1305. The ends of the first air outlet pipe 1304 and the second air outlet pipe 1305 away from the air intake box 1301 are both connected to the annular tube 1302, and the annular tube 1302 faces the air intake box 1301. The side wall of the air inlet box 1301 is evenly connected with an air outlet head 1306, a card slot 1208 is opened on the mounting plate 1201, a card block 1303 matching the card slot 1208 is fixed on the side wall of the air inlet box 1301, and the second air outlet pipe 1305 is a spring tube; two piston plates 1308 are movably arranged in the air inlet box 1301, one end of the two first air outlet pipes 1304 extends into the air inlet box 1301 and is connected to the piston plate 1308, and the first air outlet pipe 1304 passes through the piston plate 1308, and a horizontal plate 1309 is fixed in the air inlet box 1301 , the horizontal plate 1309 is located between the two piston plates 1308, a cooling source 1310 is arranged below the horizontal plate 1309, and springs 1311 are connected to the side walls of the two piston plates 1308 that are away from each other, and the cooling source 1310 is an ice cube; after the welding is completed, the driving source continues to drive the slider 1202 and the mounting plate 1201 to descend, and the air inlet box 1301 will stay on the top packaging substrate 2, and a section of the first air outlet pipe 1304 located outside the air inlet box 1301 is in a relaxed state, and a section located inside the air inlet box 1301 is in a tight state In the state, when the annular tube 1302 descends with the mounting plate 1201, an external air source is used to inflate the air inlet box 1301, and the welding point is cooled by air cooling. As the annular tube 1302 continues to descend, the first air outlet pipe 1304 is gradually tightened and pulls the piston plate 1308 to move. At this time, the cooling source 1310 will cool the air and then dissipate the heat at the welding point, realizing gradient heat dissipation. The temperature change is smoother, which helps to reduce the internal stress caused by temperature differences, thereby reducing the possibility of welding stress and deformation.

[0023] A packaging method for a three-dimensional airtight packaging structure comprises the following steps: S1, placing a sealing material layer 4 on the top of the side wall 3; S2, splicing the convex strip 6 at the bottom of the top packaging substrate 2 with the groove 5 at the top of the side wall 3; S3, welding is performed in the welding chamber 10 to form an airtight packaging structure, and pressure is applied to the top packaging substrate 2 by the pressure applying mechanism 12 during welding; S4. After welding is completed, the temperature of the welding point is cooled by the cooling mechanism 13.

[0024] The working principle of the present invention is as follows: a sealing material layer 4 is placed on the top of the side wall 3, and the convex strip 6 at the bottom of the top packaging substrate 2 is spliced ​​with the groove 5 at the top of the side wall 3. The splicing of the groove 5 and the convex strip 6 ensures both the accuracy and efficiency of the connection. At the same time, the convex strip 6 squeezes the arched protrusion 9 to move the hot melt adhesive strips 8 on both sides. The hot melt adhesive strips 8 are close to the connection between the convex strip 6 and the sink 7, and then the product is placed in the welding cabin 10 for welding. After the welding is heated, the hot melt adhesive strip 8 melts, further improving the sealing effect. During welding, a driving source (not shown) is used to drive the slider 1202 to descend, so that the pressure wheel 1207 contacts the top packaging substrate 2, and the torsion spring 1205 is used to apply appropriate pressure to it to ensure the welding effect. After welding is completed, the driving source is used to continue to drive the slider 1202 and the mounting plate 1201 to descend, and the annular tube 1302 is synchronously descended, and an external air source (not shown) is used to inflate the air inlet box 1301, and the air is discharged through the air outlet head 1306 to cool the welding point. At this time, the air temperature is close to room temperature. As the annular tube 1302 continues to descend, the first air outlet pipe 1304 will pull the piston plate 1308 to move, exposing the cooling source 1310, and the air contacts the cooling source 1310. The air temperature gradually decreases, and then the welding point is quickly cooled, realizing gradient heat dissipation at the welding point, and the temperature change is more gentle, which helps to reduce the internal stress caused by temperature differences, thereby reducing the possibility of welding stress and deformation.

[0025] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A three-dimensional hermetic packaging structure, comprising a bottom packaging substrate (1), a top packaging substrate (2), and a side wall (3) arranged on the bottom packaging substrate (1), characterized in that: A frame-shaped sealing material layer (4) is provided between the top packaging substrate (2) and the bottom packaging substrate (1); a frame-shaped groove (5) is provided on the top of the side wall (3); a convex strip (6) matching the groove (5) is provided on the side wall of the top packaging substrate (2) facing the side wall (3); a chip module is provided on the bottom packaging substrate (1); and the side wall (3) and the top packaging substrate (2) are airtightly integrated by airtight welding to form an airtight packaging structure; The airtight packaging structure is placed in a welding cabin (10) to carry out welding work.

2. A three-dimensional airtight packaging structure according to claim 1, characterized in that: A sink groove (7) with an arc-shaped cross section is provided at the bottom of the groove (5), and hot-melt adhesive strips (8) are provided on both sides of the sink groove (7).

3. A three-dimensional airtight packaging structure according to claim 2, characterized in that: An arched protrusion (9) is connected between the hot melt adhesive strips (8) on both sides.

4. A three-dimensional airtight packaging structure according to claim 1, characterized in that: Two slide grooves (11) are provided on the inner walls on both sides of the welding chamber (10), and a pressure mechanism (12) is slidably connected between the slide grooves (11) on both sides. The pressure mechanism (12) comprises two mounting plates (1201), and sliding blocks (1202) are fixed on the side walls of the two mounting plates (1201) that are far away from each other, and the sliding blocks (1202) are slidably connected to the slide grooves (11), and two fixed columns (1203) are fixed on the side walls of the two mounting plates (1201) that are close to each other, and two rotating sleeves (1204) are rotatably installed on the fixed columns (1203), and a torsion spring (1205) is connected between the rotating sleeve (1204) and the mounting plate (1201), and a mounting frame (1206) is fixed to the rotating sleeve (1204), and a pressure wheel (1207) is installed at one end of the mounting frame (1206).

5. A three-dimensional airtight packaging structure according to claim 4, characterized in that: It also includes a driving source for driving the pressure applying mechanism (12) to move up and down.

6. A three-dimensional airtight packaging structure according to claim 4, characterized in that: The pressure-applying mechanism (12) is provided with a cooling mechanism (13), the cooling mechanism (13) comprising an air intake box (1301) and an annular tube (1302) fixed on the mounting plate (1201), the air intake box (1301) being connected to an air intake pipe (1307), the two side walls of the air intake box (1301) being connected to a first air outlet pipe (1304), and the other two side walls being connected to a second air outlet pipe (1305), the first air outlet pipe (1304) and the second air outlet pipe (1305) being connected to each other. One end of the two air outlet pipes (1305) away from the air inlet box (1301) is connected to the annular tube (1302), and the side wall of the annular tube (1302) facing the air inlet box (1301) is evenly connected with an air outlet head (1306), a slot (1208) is provided on the mounting plate (1201), and a block (1303) matching the slot (1208) is fixed on the side wall of the air inlet box (1301), and the second air outlet pipe (1305) is a spring tube.

7. A three-dimensional airtight packaging structure according to claim 6, characterized in that: Two piston plates (1308) are movably arranged in the air intake box (1301), one end of two first air outlet pipes (1304) extends into the air intake box (1301) and is connected to the piston plate (1308), and the first air outlet pipes (1304) penetrate the piston plate (1308), a transverse plate (1309) is fixed in the air intake box (1301), the transverse plate (1309) is located between the two piston plates (1308), a cooling source (1310) is arranged below the transverse plate (1309), and springs (1311) are connected to the side walls of the two piston plates (1308) that are away from each other.

8. A three-dimensional airtight packaging structure according to claim 7, characterized in that: The cooling source (1310) is ice cubes.

9. A packaging method for a three-dimensional airtight packaging structure according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1, placing a sealing material layer (4) on the top of the side wall (3); S2, splicing the convex strip (6) at the bottom of the top packaging substrate (2) and the groove (5) at the top of the side wall (3); S3, welding is performed in the welding chamber (10) to form an airtight packaging structure, and pressure is applied to the top packaging substrate (2) using a pressure applying mechanism (12) during welding; S4. After welding is completed, the temperature of the weld is cooled by a cooling mechanism (13).

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