GaN high-power device heterogeneous integrated T / R assembly based on embedded flow channel

Abstract

The invention discloses a GaN high-power device heterogeneous integrated T / R assembly based on an embedded flow channel, which belongs to the field of phased array radar T / R assemblies and comprises a packaging shell, an LTCC (Low Temperature Co-Fired Ceramic) substrate, a PCB (Printed Circuit Board) substrate, a radio frequency coaxial connector, a low-frequency connector, a power supply modulation circuit, a beam driving control circuit and a transceiving channel circuit, the T / R assembly comprises four transceiving channels, and the working frequency band of the T / R assembly is 2GHz-6GHz; a transmitting channel chip of the T / R assembly comprises a radio frequency driving amplifier chip and a final-stage radio frequency power amplifier chip; a receiving channel chip of the T / R assembly comprises a radio frequency amplitude-limiting low-noise multifunctional chip. A common part chip of the T / R assembly comprises a wave control driver chip, a radio frequency multifunctional chip, a radio frequency switch chip and a power divider chip. The T / R assembly can be widely applied to a phased array radar system with the frequency band of 2GHz-6GHz, and the thermal management requirement of the system is ensured while high performance is realized.

Description

Technical Field

[0001] The present invention belongs to the field of phased array radar T / R components and module heat dissipation, and specifically relates to a GaN high-power device heterogeneous integrated T / R component based on an embedded flow channel. Background Art

[0002] The phased array radar T / R component is an important part of the phased array radar system and an important device that determines the RF performance of the phased array radar. The T / R component is usually composed of RF circuits, power modulation circuits, and beam drive control circuits, and is used to realize the transmission, reception, amplification, and phase shift attenuation control of RF signals.

[0003] The three-dimensional integrated structure is a structure that can effectively improve the integration of microsystems. The T / R component with a three-dimensional integrated structure can transmit signals in the vertical direction of the substrate. The local components are encapsulated inside the T / R component, which helps to reduce the size of the T / R component and improve the integration. Based on the rapid development of monolithic microwave integrated circuits (Monolithic Microwave Integrated Circuit, abbreviated as MMIC), the power supply power and transmission power of the GaN high-power RF power amplifier in the T / R component have increased accordingly. At the same time, the three-dimensional integrated structure also increases the heat dissipation pressure of the T / R component. Thermal management has become a technical problem for the practical application of GaN RF power amplifier chips. Today's T / R components need to use more efficient heat dissipation technology to meet their heat dissipation needs. Embedded heat dissipation technology is a high-efficiency, integrated, and miniaturized liquid cooling technology. Embedding the flow channel inside the T / R component can greatly reduce the system size. Based on this technical feature, a GaN high-power device heterogeneous integrated T / R component based on embedded flow channel is designed. Summary of the invention

[0004] To solve the above problems, the present invention discloses a GaN high-power device heterogeneously integrated T / R component based on embedded flow channels, which is applied to 2GHz-6GHz phased array radar. A three-dimensional integrated packaging structure is used to heterogeneously integrate the circuit substrate. At the same time, the embedded flow channel heat dissipation design is combined to improve the heat dissipation efficiency of the T / R component and meet the high heat dissipation requirements of GaN high-power devices, thereby improving the component performance.

[0005] To achieve the above-mentioned object, the technical scheme of the present invention is as follows: a GaN high-power device heterogeneous integrated T / R component based on an embedded flow channel is a four-channel multi-chip module (Multi-Chip Module, MCM), including a packaging shell, a low-temperature co-fired ceramic substrate (LTCC substrate), a printed circuit board (PCB substrate), a radio frequency coaxial connector, a low-frequency connector, a power modulation circuit, a beam driving control circuit and a transceiver channel circuit; The main body of the component substrate is composed of two heterogeneous substrates (LTCC substrate and PCB substrate) stacked together. The overall structure includes a ceramic cover, surface mount devices, LTCC substrate front chip, front cavity, LTCC substrate, vertical vias, back cavity, heat exchange area, PCB 1, PCB 2, PCB 3, total inlet of cooling medium, SMP connector pin port, total outlet of cooling medium, back cavity RF chip, BGA solder ball and front cavity RF chip. Among them, the surface mount devices include resistors, capacitors, surface mount SMP RF coaxial connectors and surface mount micro rectangular connectors; the front chip of the LTCC substrate includes a variety of power modulation chips and wave control driver chips; the back cavity RF chip includes the final stage RF power amplifier chip, RF limiting low noise multifunctional chip, RF switch chip and power modulation chip of RF switch chip; the front cavity RF chip includes RF multifunctional chip, RF driver amplifier chip and power divider chip. The LTCC substrate and the PCB substrate are connected by ball grid array technology (BGA solder ball), and the PCB substrate is stacked by PCB 1, PCB 2 and PCB 3.

[0006] Furthermore, the LTCC substrate is provided with a total of 25 layers of substrates, which can be divided into 5 parts according to the main functions, including the top layer, the multi-layer wiring layer, the transmission line structure layer, the +28V power supply layer and the back cavity layer. The circuit module is set on the top layer (1st layer) of the LTCC substrate. The 1st to 8th layers (including 7 layers of substrate) are the multi-layer wiring layers, and their main function is to realize the routing of power modulation signals and beam drive control signals. Since the order of the signal metal pads of the beam control driver chip is inconsistent with the order of the signal metal pads of the RF multi-function chip, it is necessary to use the advantages of the multi-layer wiring of the LTCC substrate to realize the crossing of the routing and connect the corresponding signal terminals. The 8th to 18th layers (a total of 11 circuit layers, including 10 layers of substrate) are the transmission line structure layers, and the transmission line structure adopted is a stripline structure. Considering the process line width limitation and process accuracy, the stripline structure layer is provided with a total of 10 layers of substrate, which can obtain a suitable line width and a relatively stable stripline characteristic impedance. In order to avoid the substrate thickness being too large, the transmission lines of the transmitting channel and the receiving channel are designed on the same layer, and the ground plane is used to isolate different routing lines. The 13th layer is the stripline routing layer, which is responsible for the RF signal transmission between each RF chip in the LTCC substrate. The stripline structure in the 13th layer is interconnected with the devices or transmission lines at both ends through vertical vias, and a circle of grounded vertical vias is designed around it to form a coaxial structure to reduce interference from external signals, improve the transmission line matching effect, and achieve good RF transmission performance. The 19th layer is the +28V power supply layer. Since the +28V power supply has a large working current and high power, a separate layer is set for the +28V power supply. Ground layers are set on the upper and lower layers (18th and 20th layers) of the +28V power supply layer to isolate the +28V power supply layer from other circuits and reduce signal crosstalk. The 20th to 25th layers are the back cavity layers (including 5 layers of substrates), which reserve sufficient assembly space for the reverse cavity RF chip. BGA pads are set at the bottom of the LTCC substrate. The layout of the BGA pads corresponds to the surface BGA pad layout of the PCB. Its function is to realize the transmission of power modulation signals and RF signals between the LTCC substrate and the PCB substrate, as well as large-area grounding. At the same time, it can help realize the mechanical interconnection between the LTCC substrate and the PCB substrate.

[0007] Furthermore, the LTCC substrate is provided with a front cavity and a back cavity. The depth of the front cavity is the thickness of 7 layers of LTCC, and there are five front cavities, namely a one-channel cavity, a two-channel cavity, a three-channel cavity, a four-channel cavity and a power divider chip cavity. The power divider chip cavity is equipped with a power divider chip, which is located at the center of the front of the LTCC substrate. The one-channel cavity, the two-channel cavity, the three-channel cavity, and the four-channel cavity are equipped with a radio frequency multifunctional chip and a radio frequency driving amplifier chip, which are respectively distributed in the area around the power divider chip cavity. The ceramic cover plate is arranged above the front cavity to cover and protect the cavity, a metal layer is designed in the substrate area around the cavity, and a bonding process is adopted to realize the packaging protection function of the ceramic cover plate and the electrical signal conduction; the depth of the reverse cavity is equal to the thickness of 5 layers of LTCC, and the components in the reverse cavity are mounted on the surface of the PCB one. The cavity covers the surface components of the PCB one, and mounting the components in the cavity on the surface of the PCB substrate is conducive to passing cooling medium into the bottom of the high-power device to achieve heat dissipation performance.

[0008] Furthermore, the PCB substrate is composed of a total of three independent PCB substrates stacked together, and the three PCB substrates are stacked and assembled from top to bottom in the order of PCB 1, PCB 2, and PCB 3. PCB 1, PCB 2, and PCB 3 are all double-layer boards, wherein the dielectric thickness of PCB 1 is 0.508 mm, the thickness of the finished board is 0.6 mm, and the thickness of the finished boards of PCB 2 and PCB 3 is 0.9 mm. The front side of PCB 1 is designed with a transceiver link, and is provided with the final-stage RF power amplifier chip, the RF limiting low-noise multifunctional chip, and the RF switch chip. The dielectric is dug out at the bottom of the final-stage RF power amplifier to form a cavity (heat exchange area) for the cooling medium to flow and contact with the substrate of the final-stage RF power amplifier. The back side of PCB 1 cooperates with the front side of PCB 2 for stacking and interconnection. The front window of the PCB 2 forms a cooling medium inlet and a cooling medium outlet for the power amplifier. The back of the PCB 2 is provided with an embedded channel heat dissipation structure according to a pattern. The embedded channel heat dissipation structure is used to divert liquid. The cooling liquid introduced into the cooling medium total inlet is distributed to the bottom of the final RF power amplifier of the four channels, and finally flows out of the cooling medium total outlet. The PCB 3 digs out the medium at the corresponding position of the cooling medium total inlet and the cooling medium total outlet, cooperates with the PCB 2, closes the embedded channel heat dissipation structure, and realizes stacking and interconnection.

[0009] Furthermore, the circuit module of the GaN high-power device heterogeneously integrated T / R component based on embedded flow channels includes a power modulation circuit, a beam drive control circuit and a transceiver channel circuit.

[0010] Furthermore, the power modulation circuit and the beam drive control circuit are arranged on the surface of the LTCC substrate, and all kinds of power modulation chips used are bare chips. The power modulation circuit includes a +28V power modulation circuit, a +5V power modulation circuit, a -5V power modulation circuit and a -40V power modulation circuit, wherein the +28V power modulation circuit provides drain power modulation for the final RF power amplifier chip, the +5V power modulation circuit provides power modulation for the RF multi-function chip, the RF drive amplifier chip and the RF limiting low noise multi-function chip, the -5V power modulation circuit provides gate power modulation for the final RF power amplifier, and the -40V power modulation circuit provides power modulation for the RF switch chip.

[0011] Furthermore, the power modulation circuit is mainly composed of a power modulation chip suitable for the working voltage and working current of the selected RF chip, and the power modulation chip is controlled by TTL level and can output the required power modulation pulse to realize the power switch control function of the selected RF chip of the present invention, wherein the TTL level is generated by the wave control driver chip. In addition, the +28V power modulation circuit also combines the high-voltage PMOS tube to perform drain modulation on the GaN high-power device.

[0012] Furthermore, the beam drive control circuit includes a beam control driver chip and a radio frequency multifunctional chip, which are responsible for converting the external input serial control signal into the phase shift attenuation control signal of the four-channel radio frequency multifunctional chip of the T / R component. At the same time, the beam drive control circuit is also responsible for converting the external input logic control signal into a TTL level to control each power modulation chip in the power modulation circuit. The beam control driver chip can perform beam drive control on 5 channels. In the present invention, 4 channel functions are selected for control, and each channel can provide 6 phase shift signals, 6 attenuation signals, 2 switch control signals and transceiver control signals, wherein the 6 phase shift attenuation signals are connected to the radio frequency multifunctional chip, the 2 switch control signals are connected to the power modulation chip of the radio frequency switch chip, and the transceiver control signal is connected to the power modulation chip of each radio frequency chip.

[0013] Furthermore, the signal transmission port of the T / R component is perpendicular to the substrate, thereby realizing vertical transmission of external signals.

[0014] Furthermore, the power modulation circuit in the LTCC substrate and the beam driving control signal are interconnected through bonding gold wires, multi-layer wiring of the LTCC substrate, vertical vias and metal wires, and the RF chip power modulation signal in the PCB substrate is interconnected through bonding gold wires, metal wires and the BGA solder balls.

[0015] Furthermore, the transceiver channel circuit includes the power divider chip, the RF multifunctional chip, the RF driver amplifier chip, the final RF power amplifier chip, the RF limiting low-noise multifunctional chip and a transmission line structure. The RF chips are all bare chips and are all arranged in the cavity, so as to form isolation between the power modulation circuit and the beam drive control circuit and the transceiver channel circuit. The power modulation circuit of each RF chip is connected through metal wires and metal pads, and connected to the RF chip through bonding gold wires.

[0016] Furthermore, in the present invention, in order to realize the signal transmission and reception functions, a transmission channel circuit and a receiving channel circuit are provided, and each channel realizes the function by selecting a number of RF chips. The transmission channel RF chip includes the RF driver amplifier chip and the final RF power amplifier chip. The transmission channel has a total of 3 stages of amplification, namely, the RF multi-function chip amplification, the RF driver amplifier chip amplification, and the final RF power amplifier chip amplification. The saturated output power of the final RF power amplifier chip can reach 46dBm. Among them, the operating frequency band of the RF driver amplifier chip is 1.9GHz-6.1GHz, and the operating voltage is +5V. The operating frequency band of the final RF power amplifier chip is 2GHz-6.2GHz, and the operating voltage is +28V.

[0017] Furthermore, in the present invention, the receiving channel RF chip includes the RF limiting low noise multifunctional chip, which integrates the limiter and low noise amplification functions on one MMIC. The receiving channel has two stages of amplification, namely the RF limiting low noise multifunctional chip and the RF multifunctional chip. The RF limiting low noise multifunctional chip has an operating frequency band of 2GHz-6GHz, an operating voltage of +5V, a receiving gain of 26dB, and a noise figure of 1.2dB.

[0018] Furthermore, at the antenna end, the transmitting channel and the receiving channel share a port, and the RF switch chip SW is used to achieve the isolation and switching of the transmitting and receiving channels. The RF switch chip is a single-pole double-throw switch with an operating frequency band of 0.1GHz-6GHz, an isolation of 50dB, and an insertion loss of 1.2dB.

[0019] Furthermore, as a GaN high-power device, the final-stage RF power amplifier chip has a saturated output power of 46dBm, has a high heat flux density, and is also the main heat source in the T / R component. The present invention designs an embedded channel heat dissipation structure for heat dissipation of the final-stage RF power amplifier chip in four channels. The overall structure of the embedded channel heat dissipation structure is a one-to-four design, with a total cooling medium inlet and a total cooling medium outlet. After the PCB 1 and PCB 2 are stacked, a curved channel is formed under the final-stage RF power amplifier chip. The cooling medium flows from the PCB 2 channel into the PCB 1, impacting the final-stage RF power amplifier chip substrate to achieve a heat dissipation effect.

[0020] Furthermore, all signal input and output of the present invention are realized through connectors. A surface-mounted micro rectangular connector and a surface-mounted SMP RF coaxial connector are provided on the surface of the LTCC substrate, and the +28V power supply, +5V power supply, -5V power supply, -40V power supply and 13-bit control signal are input through the surface-mounted micro rectangular connector, and the main port RF signal is transmitted through the surface-mounted SMP RF coaxial connector. On the reverse side of the PCB three, a pin-type SMP RF coaxial connector is provided, and the branch port RF signal is transmitted through the pin-type SMP RF coaxial connector.

[0021] The power supply and control signal ports of the T / R components are low-frequency connectors and are mounted on the front side of the LTCC substrate; The low-frequency connector is a 65-core micro rectangular connector, which is assembled by vertically welding on the pad; The 13 pins in the low-frequency connector are used for the control signals of the wave-controlled driver chip, and are set to pins 9 to 21; The 52 pins in the low-frequency connector are used for various power supplies and grounding of the T / R component, including +5V power supply, -5V power supply, +28V power supply and -40V power supply. Among them, pins 1 to 7 are the +5V power supply, pin 8 is the -40V power supply, pin 22 is the -5V power supply, pins 23 to 43 are GND, and pins 44 to 65 are the +28V power supply.

[0022] The beneficial effects of the present invention are as follows: the GaN high-power device heterogeneous integrated T / R component based on embedded flow channels of the present invention adopts a three-dimensional integrated packaging structure, and through a heterogeneous integrated circuit substrate and an embedded flow channel heat dissipation design, the heat dissipation efficiency of the T / R component is improved, and efficient heat dissipation and miniaturization design are achieved; the component can be widely used in phased array radar systems with a frequency band of 2GHz-6GHz, ensuring the thermal management requirements of the system while achieving high performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the substrate stacking structure design of the present invention; Figure 2 This is a schematic diagram of the top layer layout of the LTCC substrate of the present invention; Figure 3 This is a schematic diagram of the reverse layout of the LTCC substrate of the present invention; Figure 4 This is a schematic diagram of the PCB substrate circuit layout of the present invention; Figure 5 This is a schematic diagram of the embedded flow channel in the second PCB of the whole machine of the present invention; Figure 6 It is a three-dimensional schematic diagram of the heat dissipation structure of the whole flow channel of the present invention; Figure 7 It is a schematic diagram of the packaging shell of the present invention.

[0024] List of Figure Symbols: 1. Ceramic cover plate, 2. Surface mount device, 3. LTCC substrate front chip, 4. Front cavity, 5. LTCC substrate, 6. Vertical via, 7. Rear cavity, 8. Heat exchange area, 9. PCB one, 10. PCB two, 11. PCB three, 12. Cooling medium total inlet, 13. SMP connector pin port, 14. Cooling medium total outlet, 15. Rear cavity RF chip, 16. BGA solder ball, 17. Front cavity RF chip; 100, one-channel cavity, 101, two-channel cavity, 102, three-channel cavity, 103, four-channel cavity, 104, power divider chip cavity, 105, total port SMP RF coaxial connector, 106, J63A micro rectangular connector; 200, one channel back cavity, 201, two channel back cavity, 202, three channel back cavity, 203, four channel back cavity, 204, one channel transmitting channel pad, 205, one channel receiving channel pad, 206, two channel transmitting channel pad, 207, two channel receiving channel pad, 208, three channel transmitting channel pad, 209, three channel receiving channel pad, 210, four channel transmitting channel pad, 211, four channel receiving channel pad; 300, final stage RF power amplifier chip, 301, limiting low noise multifunctional chip, 302, RF switch chip; 400, one-channel power amplifier cooling medium inlet, 401, one-channel power amplifier cooling medium outlet, 402, two-channel power amplifier cooling medium inlet, 403, two-channel power amplifier cooling medium outlet, 404, three-channel power amplifier cooling medium inlet, 405, three-channel power amplifier cooling medium outlet, 406, four-channel power amplifier cooling medium inlet, 407, four-channel power amplifier cooling medium outlet. DETAILED DESCRIPTION

[0025] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0026] like Figure 7 As shown, the GaN high-power device heterogeneous integrated T / R component based on embedded flow channels described in the present invention is a three-dimensional integrated chip T / R component. The packaging structure of the present invention is mainly a three-dimensional stacked assembly of substrates. The substrate is located in a single cavity of the packaging shell. The packaging shell consists of a frame and a base. The frame and the base are integrated through mechanical processing to form a single cavity for mounting the entire substrate. There are several through holes in the base, 4 of which correspond to the four-channel branch ports for welding the pin-type SMP RF coaxial connector, and 2 through holes correspond to the present invention. Figure 1 There is a cooling medium main inlet 12 and a cooling medium main outlet 14 .

[0027] The substrate as a whole is composed of an LTCC substrate 5 and PCB 1, PCB 2, and PCB 3. External signals are interconnected with components through different connectors, different voltage power supplies and beam drive control signals are interconnected through the J63A micro rectangular connector 106, the main port RF signal is interconnected through the main port SMP RF coaxial connector 105, and the sub-port RF signal is interconnected through the pin-type SMP RF coaxial connector. All three connectors are assembled using a welding process. After the voltage power supply signal and the beam drive control signal enter the substrate through the J63A micro rectangular connector 106, they are connected to the corresponding signal pads through the multi-layer metal wires and vertical vias 6 inside the LTCC substrate 5.

[0028] In the present invention, the chip 3 on the front side of the LTCC substrate includes a variety of power modulation chips and wave control driver chips, which are assembled using a bonding process. In addition to the main port SMP RF coaxial connector 105 and the J63A micro rectangular connector 106, the surface mount device 2 also includes chip resistors and chip capacitors, which are assembled using a surface mount welding process. The back of the LTCC substrate 5 is designed with a BGA solder ball 16 pad, and the signals transmitted through the BGA solder ball 16 include switching power and control signals, receiving channel RF signals, and transmitting channel RF signals. In the present invention, the power modulation chip and RF chip used are both bare chips, and the signal transmission between the chip and the external wire is connected by bonding gold wire.

[0029] Figure 1In the figure, the transmission of power modulation signals, beam drive control signals and RF signals all involve the vertical transmission of signals in the multilayer circuit board and the vertical transmission of signals between substrates. Inside the LTCC, vertical vias 6 are designed for various signal transmissions. For RF signals, a quasi-coaxial structure is specially designed, which consists of a central RF via and a circle of ground vias around it. HFSS is used to simulate the impedance and loss of the quasi-coaxial structure to optimize the performance of the quasi-coaxial structure. BGA solder balls 16 are used for signal transmission between substrates. For RF signals, a quasi-coaxial structure similar to the vertical via 6 is designed to reduce the loss of RF signals when transmitted between substrates, improve the matching degree of characteristic impedance of the transmission line, and optimize the performance of the transmission line.

[0030] The present application provides a T / R component micro-assembly process flow for realizing an embedded flow channel, and the specific process flow is as follows: (1) Three-layer PCB substrate welding. Use a high-temperature bonding machine to press the three-layer PCB substrate tightly and weld it with tin-lead-silver preformed solder sheets. Set the welding temperature to 275°C and keep it warm for 5 minutes under one atmosphere. After the temperature drops, slowly reduce the air pressure and take out the PCB stacking module.

[0031] (2) Solder the PCB stacking module to the housing, and at the same time solder the final RF power amplifier to the front of the PCB substrate. The solder is tin-silver-copper solder with a melting point of 217°C.

[0032] (3) Use a hot air gun to solder the pin-type SMP RF coaxial connector to the RF port of the component. The solder is tin-silver-copper solder with a melting point of 217°C.

[0033] (4) Use conductive glue to bond the remaining chips and chip capacitors on the surface of the PCB substrate, and the baking temperature is 100°C.

[0034] (5) Gold wire bonding is performed on the PCB substrate chip.

[0035] (6) Before being combined with the PCB substrate, the LTCC substrate 5 is first subjected to the SMT process to solder the resistors, capacitors and surface mount connectors to the surface of the LTCC substrate 5. At the same time, the BGA solder balls 16 are implanted on the back pads of the LTCC substrate 5. The solder is tin-silver-copper solder with a melting point of 217°C.

[0036] (7) The LTCC substrate 5 is laminated with the PCB substrate. The solder is tin-bismuth-silver solder with a melting point of about 138°C.

[0037] (8) Conductive adhesive is used to bond the LTCC substrate 5 chip at a baking temperature of 100°C, followed by gold wire bonding.

[0038] (9) Finally, the ceramic cover plate 1 welded with the tantalum capacitor is sealed on the cavity and gold wire bonding is performed.

[0039] The specific working process of the present invention is as follows: Combination Figure 2 , Figure 3 and Figure 4 , the signal transmission path is explained. Figure 2 The system comprises a one-channel cavity 100, a two-channel cavity 101, a three-channel cavity 102 and a four-channel cavity 103, wherein a radio frequency multifunctional chip and a radio frequency driving amplifier chip are installed in the cavity, and a power divider chip cavity 104 is separately equipped with a power divider chip. Figure 4 The system includes a final-stage RF power amplifier chip 300, a RF switch chip 302 and a limiting low-noise multifunctional chip 301.

[0040] In the transmitting state, the RF transmitting signal is input from the main port SMP RF coaxial connector 105, transmitted to the power divider chip through the coaxial structure and the stripline structure (hereinafter referred to as the "transmission line structure") and divided into 4 channels of transmitting signals. Taking one channel as an example, the transmitting signal enters the main port of the RF multifunctional chip through the transmission line structure again to achieve the first-level amplification and phase shift attenuation control of the transmitting signal. Then, the transmitting signal enters the input end of the RF driver amplifier from the transmitting output end of the RF multifunctional chip through a section of coplanar waveguide to achieve the second-level amplification of the transmitting signal. After being output from the output end of the RF driver amplifier, it is transmitted to the BGA solder ball 16 corresponding to the one-channel transmitting signal through the transmission line structure, that is, Figure 3 The one-channel transmitting channel pad 204 shown in the figure is then transmitted through the coplanar waveguide on the surface of the PCB substrate into the input end of the final RF power amplifier to achieve the third-level amplification of the transmitting signal. Finally, after being output from the output end of the final RF power amplifier, it is transmitted through the RF switch chip 302 to the branch port SMP RF coaxial connector to transmit the signal to the antenna array.

[0041] In the receiving state, the RF receiving signal is input from the sub-port SMP RF coaxial connector, enters the RF switch chip 302 through the quasi-coaxial structure and the coplanar waveguide, and the RF switch chip 302 selects the receiving channel. The receiving signal is output from the RF switch chip 302 to the input end of the limiting low-noise multifunctional chip 301 to achieve low-noise amplification of the receiving signal. Then, the receiving signal is transmitted from the limiting low-noise multifunctional chip 301 through the coplanar waveguide-quasi-coaxial structure through the BGA solder ball 16 ( Figure 3 A channel receiving channel pad 205 in the LTCC substrate 5 is connected to the stripline layer, and then transmitted to the receiving input end of the RF multi-function chip by the stripline-quasi-coaxial structure-coplanar waveguide to achieve attenuation and amplification of the received signal, and finally transmitted from the main port of the RF multi-function chip through the power divider chip and output from the RF main port.

[0042] Combination Figure 1 , Figure 5 and Figure 6, the heat dissipation work is explained. When the heat dissipation work is performed, the cooling medium is pumped in from the cooling medium main inlet 12, and passes through Figure 6 As shown in the liquid separation structure embedded in the PCB substrate, the coolant flows to the cooling medium inlet of each channel power amplifier (the cooling medium inlet 400 of the one-channel power amplifier, the cooling medium inlet 402 of the two-channel power amplifier, the cooling medium inlet 404 of the three-channel power amplifier, and the cooling medium inlet 406 of the four-channel power amplifier), and flows into the heat exchange area 8 below the final RF power amplifier according to the designed structure, and then flows out from the cooling medium outlets of each channel power amplifier (the cooling medium outlet 401 of the one-channel power amplifier, the cooling medium outlet 403 of the two-channel power amplifier, the cooling medium outlet 405 of the three-channel power amplifier, and the cooling medium outlet 407 of the four-channel power amplifier) ​​and then is converged into the cooling medium total outlet 14.

[0043] It should be noted that the above content only illustrates the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications all fall within the protection scope of the claims of the present invention.

Claims

1. A GaN high-power device heterogeneously integrated T / R component based on an embedded flow channel, characterized in that: The T / R assembly is a four-channel multi-chip assembly, including a packaging shell, an LTCC substrate, a PCB substrate, an RF coaxial connector, a low-frequency connector, a power modulation circuit, a beam drive control circuit, and a transceiver channel circuit; The T / R component includes 4 transmit and receive channels, and the operating frequency band of the T / R component is 2GHz-6GHz; Among them, the transmitting channel chip of the T / R component includes the RF driver amplifier chip and the final RF power amplifier chip; the receiving channel chip of the T / R component includes the RF limiting low-noise multifunctional chip; the common part chip of the T / R component includes the wave control driver chip, the RF multifunctional chip, the RF switch chip and the power divider chip; The T / R assembly is composed of two heterogeneous substrates stacked together. The two heterogeneous substrates are an upper LTCC substrate and a lower printed circuit PCB substrate. The LTCC substrate is a low-temperature co-fired ceramic substrate, and the PCB substrate is a printed circuit board. The LTCC substrate and the PCB substrate are connected through BGA solder balls. The main RF port of the T / R assembly uses a surface-mount SMP RF coaxial connector, which is assembled on the front side of the LTCC substrate; The RF port of the T / R assembly uses a welded SMP RF coaxial connector, which is assembled on the reverse side of PCB 3; The power and control signal ports of the T / R components use low-frequency connectors and are assembled on the front side of the LTCC substrate; The PCB substrate is assembled by stacking PCB 1, PCB 2, and PCB 3 in order from top to bottom; The LTCC substrate is provided with a beam drive control circuit and a power modulation circuit, a front cavity is provided above the LTCC substrate, a ceramic cover is provided above the front cavity, a back cavity is provided between the bottom of the LTCC substrate and the surface of PCB 1, a radio frequency circuit is provided in the front cavity, including a radio frequency multifunctional chip and a radio frequency drive amplifier chip, and components in the back cavity are assembled on the surface of the lower PCB 1; The beam drive control circuit converts the external control signal into a power modulation circuit control signal, a radio frequency switch signal, and a radio frequency multifunctional phase shift attenuation signal; The power modulation circuit converts power modulations of different voltages into power modulation signals for each RF chip; The T / R components use embedded channel liquid cooling to dissipate heat. The channel structure is integrated inside the PCB substrate to achieve multi-channel chip heat dissipation. The front of PCB 1 is provided with a radio frequency circuit, including a final-stage radio frequency power amplifier chip, a radio frequency limiting low-noise multifunctional chip, and a radio frequency switch chip; PCB 2 is provided with an embedded flow channel heat dissipation structure; and PCB 3 is provided with a cooling medium inlet and a cooling medium outlet; The embedded channel heat dissipation structure is closed by welding and bonding three layers of PCB substrate to form a channel structure.

2. The GaN high-power device heterogeneous integrated T / R component based on embedded flow channel according to claim 1, characterized in that: The LTCC substrate has a total of 25 layers. The 1st to 7th layers are multi-layer wiring layers, which are used for interconnecting the beam drive control circuit and the low-power power modulation circuit. The 8th to 18th layers are stripline structures, which are used for RF signal transmission of 4 transceiver channels. Among them, the 8th and 18th layers are ground layers, the 13th layer is a stripline layer, the 19th layer is a +28V power layer, which is used for +28V power supply, the 20th layer is a ground layer, which is used to isolate the +28V power layer, and the 21st to 25th layers are frame layers. The corresponding cavity is designed for the frame layer so that the LTCC substrate can cover the chip on the PCB substrate during assembly; vertical vias are provided inside the LTCC substrate for signal transmission.

3. The GaN high-power device heterogeneous integrated T / R component based on embedded flow channel according to claim 1, characterized in that: The signal transmission port of the T / R component is located in the vertical direction of the substrate, realizing the vertical transmission of external signals and achieving the X / Y direction expansion of the T / R component.

4. The GaN high-power device heterogeneous integrated T / R component based on embedded flow channel according to claim 1, characterized in that: The low-frequency connector is a 65-core micro rectangular connector, which is assembled by vertically soldering to the pad; The 13 pins in the low-frequency connector are used for the control signals of the wave-controlled driver chip, which are set to pins 9 to 21; The 52 pins in the low-frequency connector are used for various power supplies and grounding of the T / R components, including +5V power supply, -5V power supply, +28V power supply and -40V power supply; among them, pins 1 to 7 are +5V power supply, pin 8 is -40V power supply, pin 22 is -5V power supply, pins 23 to 43 are GND, and pins 44 to 65 are +28V power supply.

5. The GaN high-power device heterogeneous integrated T / R component based on embedded flow channel according to claim 1, characterized in that: PCB 1, PCB 2 and PCB 3 are stacked by welding to form an integral body; The PCB substrate is connected to the surface of the packaging shell by welding technology, and the embedded channel heat dissipation structure in the PCB substrate and the cooling medium inlet and cooling medium outlet in the packaging shell form an integrated liquid supply structure; A window is provided at the bottom substrate of the final-stage RF power amplifier in PCB 1 for introducing cooling medium; PCB 2 is provided with two through holes at the bottom of the final-stage RF power amplifier, serving as a cooling medium inlet and a cooling medium outlet at the bottom of the final-stage RF power amplifier; The embedded channel heat dissipation structure for liquid separation is arranged on the reverse side of PCB 2, connecting the cavities at the bottom of each final-stage RF power amplifier, with a total of 1 cooling medium inlet and 1 cooling medium outlet.

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