W-band packaging antenna

Abstract

The invention belongs to the technical field of high-integration phased-array antennas, and particularly relates to a W-band packaged antenna. The SOC chip is embedded in the blind slot, and the SOC chip is adhered to the bottom of the blind slot; the blind groove is filled with the liquid metal, and the liquid metal wraps the outside of the SOC chip; the metal cover plate is connected with the opening of the blind groove in a sealing and welding mode, and the metal cover plate and the blind groove form an airtight cavity. And the BGA solder ball is arranged on a bonding pad of the HTCC substrate. On one hand, airtight level protection on the chip can be realized, and on the other hand, the heat conduction efficiency can be obviously improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of highly integrated phased array antennas, and in particular relates to a W-band packaged antenna. Background Art

[0002] In the design of the two-dimensional densely distributed phased array antenna in the W band, due to the short wavelength of the W band, the spacing between the antenna elements is small, the wiring density between the antenna elements and the TR chip is high, the design and processing are difficult, and the design and process route selection are required to be high. At present, the process of packaging substrate is used to realize the integration of W-band high-density antenna and multi-functional SOC chip, which has the characteristics of high integration and strong manufacturability. However, since the SOC chip and the packaging substrate are directly interconnected through the SMT process, the packaging substrate itself is not dense and has high hygroscopicity. At the same time, the SOC chip is directly exposed to the outside and cannot be completely isolated from oxygen, water vapor, etc. in the air. Therefore, this architecture cannot achieve airtightness. In addition, due to the poor thermal conductivity of the packaging substrate, it can usually only be contacted with the heat sink through the back of the SOC chip, and the contact area between the SOC chip and the heat sink is limited. At the same time, because the SOC chip is brittle, the heat sink cannot directly contact the chip, and a soft thermal conductive material transition is required in the middle, which will increase the thermal resistance. Summary of the invention

[0003] The technical problem to be solved by the present invention is that the existing W-band packaged antenna has poor air tightness and poor heat dissipation performance.

[0004] The present invention is achieved through the following technical solutions: In a first aspect, a W-band packaged antenna is provided, comprising: a SOC chip, liquid metal, a metal cover plate, a BGA solder ball and a HTCC substrate; a blind groove is provided on the surface of the HTCC substrate; the SOC chip is embedded in the blind groove, and the SOC chip is bonded to the bottom of the blind groove; the liquid metal is filled in the blind groove, and the liquid metal is wrapped around the outside of the SOC chip; the metal cover plate is sealed and welded to the opening of the blind groove, and the metal cover plate and the blind groove form an airtight cavity; the BGA solder ball is provided on the solder pad of the HTCC substrate.

[0005] Furthermore, the HTCC substrate and the SOC chip are interconnected via a suspended microstrip line to reduce transmission loss between the SOC chip and the antenna patch.

[0006] Furthermore, the inner surface of the metal cover plate is in contact with the liquid metal.

[0007] Furthermore, the material of the HTCC substrate is aluminum oxide, the liquid metal is gallium silicon liquid metal, and the material of the metal cover plate is Kovar alloy.

[0008] In a second aspect, a W-band packaged antenna assembly method is provided, comprising the following steps: providing a blind groove on an HTCC substrate, placing a SOC chip into the blind groove, and bonding the SOC chip to the bottom of the blind groove; performing underfilling between the SOC chip and the bottom of the HTCC blind groove; filling the blind groove with liquid metal so that the liquid metal wraps the SOC chip; placing a metal cover plate at the opening of the blind groove so that the metal cover plate contacts the liquid metal; sealing and welding the metal cover plate to the opening of the blind groove so that the metal cover plate and the blind groove form an airtight cavity; and providing a BGA solder ball on the solder pad of the HTCC substrate.

[0009] Furthermore, the sealing connection includes: laser welding or brazing.

[0010] Furthermore, the assembly method further comprises the following steps: interconnecting the HTCC substrate and the SOC chip via a suspended microstrip line.

[0011] Compared with the prior art, the present invention has the following advantages and beneficial effects: On the one hand, the airtight HTCC substrate and independent blind groove cavity are used to enclose and wrap the SOC chip to achieve airtight protection for the chip. On the other hand, the high thermal conductivity substrate and fully wrapped liquid metal are used to efficiently export the heat from both sides of the chip, which can significantly improve the thermal conductivity efficiency. In addition, the SOC chip is sealed in an independent blind groove cavity using liquid metal and a metal cover to form a fully wrapped metal shielding cover, which can effectively isolate other electromagnetic interference from the outside world; the isolation ground holes, blind cavities, liquid metal and sealed metal cover of the multi-layer HTCC substrate can also work together to improve the isolation between chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings: Figure 1 A cross-sectional view of a W-band packaged antenna provided in an embodiment of the present invention.

[0013] Figure 2 A top view of the W-band packaged antenna before being covered with a metal cover provided in an embodiment of the present invention.

[0014] Figure 3 A top view of a W-band packaged antenna covered with a metal cover provided by an embodiment of the present invention.

[0015] Figure 4 A bottom plan view of a W-band packaged antenna provided in an embodiment of the present invention.

[0016] Marks and corresponding parts names in the attached drawings: 1-SOC chip; 2-liquid metal; 3-metal cover, 4-BGA solder ball, 5-HTCC substrate, 6-blind groove, 7-cover sealing welding surface, 10 antenna patch, 11-isolated ground hole, 12-suspended microstrip line. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the embodiments. The schematic implementation mode of the present invention and its description are only used to explain the present invention and are not intended to limit the present invention. The embodiments described below are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0018] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to those of ordinary skill in the art that these specific details do not have to be employed to practice the present invention. In other embodiments, in order to avoid confusing the present invention, known structures, materials or methods are not specifically described. The materials, instruments and reagents used in the following examples, unless otherwise specified, can be obtained from commercial sources. The technical means used in the examples, unless otherwise specified, are conventional means well known to those skilled in the art.

[0019] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0020] Embodiment: Provide a W-band packaged antenna, such as Figure 1As shown, it includes: a SOC chip 1, liquid metal 2, a metal cover plate 3, a BGA solder ball 4 and a HTCC substrate 5. Among them, the HTCC substrate 5 is a multi-layer Al2O3 plate prepared by tape casting and high-temperature co-firing process. A blind groove 6 is provided on the surface of the HTCC substrate 5, and the size of the blind groove 6 is customized according to the SOC chip 1 (for example, 3mm×3mm×0.5mm), and the SOC chip includes a Bump copper column. A suspended microstrip line 12 (line width 50μm, dielectric layer thickness 100μm, impedance matching to 50Ω) is provided on the inner layer of the HTCC substrate 5, and the suspended microstrip line 12 interconnects the HTCC substrate 5 with the SOC chip 1. The SOC chip is welded in the blind groove of the HTCC substrate through the bottom Bump, and the welding temperature is 217°C. After welding, the bottom fill is filled between the Bump copper columns at the bottom of the chip. The liquid metal 2 is filled in the blind groove 6, and the liquid metal 2 is gallium silicon (Ga 80 Si 20 ), completely covering the chip surface and sidewalls. Figure 2 As shown, four blind slots 6 are arranged on the HTCC substrate 5 of the W-band packaged antenna, each blind slot 6 corresponds to a SOC chip 1, and the edge of the blind slot 6 cavity of the HTCC substrate 5 has a cover plate sealing welding surface 7, and the alloy cover plate (thickness 0.3mm) covers the opening of the blind slot 6 and is connected to the cover plate sealing welding surface by laser welding to achieve airtight packaging. The BGA solder ball 4 is reflow soldered on the HTCC substrate 5. The packaged W-band packaged antenna is as shown in FIG. Figure 3 As shown, its bottom plane is Figure 4 As shown, an antenna patch 10 and an isolation ground hole 11 are included.

[0021] Accordingly, the method for preparing the W-band packaged antenna comprises the following steps: Step 1: a blind groove is set on the HTCC substrate, a SOC chip is placed in the blind groove, the SOC chip is bonded to the bottom of the blind groove, and cured at 80° C. for 30 minutes.

[0022] Step 2: interconnecting the HTCC substrate and the SOC chip via suspended microstrip lines.

[0023] The bottom filler is filled between the SOC chip and the bottom of the HTCC blind groove to protect the bottom pattern of the SOC chip from contacting the liquid metal and to enhance the welding reliability of the SOC chip.

[0024] Step 3: Fill the blind groove with liquid metal so that the liquid metal wraps the SOC chip, and let it stand after filling to eliminate bubbles.

[0025] Step 4: placing a metal cover plate at the opening of the blind groove so that the metal cover plate contacts the liquid metal.

[0026] Step 5: Use laser welding or brazing to seal and connect the metal cover plate to the opening of the blind groove, so that the metal cover plate and the blind groove form an airtight cavity. The power of the laser welding is 200W, and the scanning speed is 5mm / s.

[0027] Step 6: soldering the BGA solder balls on the solder pads of the HTCC substrate by reflow soldering, with a reflow soldering peak temperature of 250° C. and a duration of 60 seconds.

[0028] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A W-band packaged antenna, characterized in that: include: A SOC chip (1), liquid metal (2), a metal cover plate (3), a BGA solder ball (4) and a HTCC substrate (5); a blind groove (6) is provided on the surface of the HTCC substrate (5); the SOC chip (1) is embedded in the blind groove (6), and the SOC chip (1) is bonded to the bottom of the blind groove (6); the liquid metal (2) is filled in the blind groove (6), and the liquid metal (2) is wrapped around the outside of the SOC chip (1); the metal cover plate (3) is sealed and welded to the opening of the blind groove (6), and the metal cover plate (3) and the blind groove (6) form an airtight cavity; and the BGA solder ball (4) is provided on the solder pad of the HTCC substrate (5).

2. The W-band packaged antenna according to claim 1, characterized in that: The HTCC substrate (5) and the SOC chip (1) are interconnected via a suspended microstrip line (12).

3. A W-band packaged antenna according to claim 1 or 2, characterized in that: The inner surface of the metal cover plate (3) is in contact with the liquid metal (2).

4. A W-band packaged antenna according to claim 1 or 2, characterized in that: The material of the HTCC substrate (5) is aluminum oxide.

5. A W-band packaged antenna according to claim 1 or 2, characterized in that: The liquid metal (2) is gallium silicon liquid metal (2).

6. A W-band packaged antenna according to claim 1 or 2, characterized in that: The material of the metal cover plate (3) is Kovar alloy.

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