A design method of a high-power switch based on thick and thin film circuit substrate

Abstract

A kind of high-power switch design method based on thick film circuit substrate, comprising: providing a surface layer circuit layer, which is provided with driver, first radio frequency transmission line, second radio frequency transmission line, third radio frequency transmission line, fourth radio frequency transmission line, first PIN diode, second PIN diode, third PIN diode, first capacitor, second capacitor, third capacitor and fourth capacitor;A sacrificial layer is provided on the lower side of the surface layer circuit layer;Multiple metal layers are provided, the first metal layer is located on the lower side of the sacrificial layer, the second metal layer is provided with first inductor, second inductor, third inductor and fourth inductor;The fourth metal layer is provided with first resistor and second resistor;The fifth metal layer is provided with driver control circuit;The adjacent two layers of metal layer are clamped with a ceramic substrate.The components of high-power switch are arranged separately in the surface layer of thin film process and the different metal layers in the interior of thick film process, to realize high integration and reduce overall size.

Description

Technical Field

[0001] This invention relates to the field of electronic information technology, and in particular to a high-power switch design method based on a thick thin-film circuit board. Background Technology

[0002] High-power switches are commonly used in radar front-ends for transmit / receive switching or operating mode switching. High-power switches must meet high-power requirements while maintaining low insertion loss and standing wave ratio (SWR). Insertion loss directly reduces the radar's output power and efficiency, while the heat loss from insertion loss increases the radar's cooling burden. SWR is a signal reflection indicator; a high SWR corresponds to significant signal reflection. Under high-power conditions, excessive reflection can damage downstream equipment and further reduce output power and efficiency.

[0003] Currently, radars are trending towards miniaturization, which requires high precision in manufacturing. Therefore, how to achieve miniaturization, high-precision manufacturing of high-power switches, and improve heat dissipation after miniaturization has become an urgent technical problem to be solved. Summary of the Invention

[0004] This invention provides a high-power switch design method based on a thick-film circuit board to overcome the shortcomings of the prior art. The method uses a thick-film-thin-film hybrid process to place electronic devices such as resistors and inductors in the inner thick-film conductor layer, and place components for control circuits in different layers. Multiple PIN diodes, drivers, multiple capacitors and multiple radio frequency transmission lines are placed on the surface layer. The layers are connected through metallized vias. Through high integration, the size of the entire system can be reduced and high-precision processing can be facilitated.

[0005] In order to achieve the objectives of this invention, the following technologies are proposed: A high-power switch design method based on a thick-film circuit substrate includes: A surface circuit layer is provided, on which a driver, a first radio frequency transmission line, a second radio frequency transmission line, a third radio frequency transmission line, a fourth radio frequency transmission line, a first PIN diode, a second PIN diode, a third PIN diode, a first capacitor, a second capacitor, a third capacitor, and a fourth capacitor are disposed; A multilayer metal layer is provided, the metal layer including at least a first metal layer, a second metal layer, a third metal layer, a fourth metal layer, a fifth metal layer and a sixth metal layer; a first inductor, a second inductor, a third inductor and a fourth inductor are disposed on the second metal layer; A first resistor and a second resistor are disposed on the fourth metal layer; A first driver control circuit and a second driver control circuit are disposed on the fifth metal layer; A multilayer ceramic substrate is provided, wherein a ceramic substrate is mounted between two adjacent metal layers.

[0006] Furthermore, a sacrificial layer is provided, which is disposed below the surface circuit layer and above the first metal layer. The sacrificial layer includes a thin film substrate, and at least one thick film sacrificial layer is disposed below the thin film substrate. The thin film substrate is disposed below the surface circuit layer, and the thick film sacrificial layer is disposed above the first metal layer. The thin film substrate is made of silicon nitride ceramic.

[0007] Furthermore, a molybdenum-copper layer is disposed below the sixth metal layer. Multiple heat dissipation holes are disposed on the surface circuit layer, and the heat dissipation holes penetrate through the molybdenum-copper layer.

[0008] Furthermore, the driver is connected to the first driver control circuit and the second driver control circuit respectively through the first channel and the second channel; the driver is also connected to the first metal layer through the third channel; the first driver control circuit and the second driver control circuit are connected to the surface circuit layer respectively through the fourth channel and the fifth channel.

[0009] Furthermore, the first RF transmission line is connected to the first inductor via the sixth channel; the second RF transmission line is connected to the third inductor via the seventh channel; the third RF transmission line is connected to the fourth inductor via the eighth channel; and the fourth RF transmission line is connected to the second inductor via the ninth channel.

[0010] Furthermore, the first inductor is connected to the third metal layer through the tenth channel; the third inductor is connected to the third metal layer through the eleventh channel; the fourth inductor is connected to the third metal layer through the twelfth channel; and the second inductor is connected to the third metal layer through the thirteenth channel.

[0011] Furthermore, the second resistor is connected to the surface circuit layer via the fourteenth and fifteenth channels; the first resistor is connected to the surface circuit layer via the sixteenth and seventeenth channels.

[0012] The advantages of the above technical solution are: First, due to the adoption of a thick-film-based multilayer structure, a multilayer wiring substrate is provided, which facilitates the wiring of multiple lines, allows for more flexible routing design, and avoids problems such as crossover and intersection of connecting lines.

[0013] Second, each electronic device module has its own independent grounding layer, and the channel used to connect the various devices is connected to the corresponding grounding layer through metallized vias. Therefore, the channel has a cavity-like isolation state, which is conducive to shielding stray signals and can improve the electromagnetic compatibility performance of the entire system.

[0014] Third, all ceramic substrates are made of silicon nitride ceramic, which has the characteristics of high relative permittivity and good thermal conductivity, thus making it easy to meet the needs of system miniaturization and high-power heat dissipation.

[0015] IV. The surface layer consists of a thin-film substrate made of silicon nitride ceramic and a thin-film surface circuit layer. At least two thick-film substrates are disposed beneath the thin-film substrate as thick-film sacrificial layers. To ensure a smooth surface, the thin-film substrate undergoes thinning, grinding, and polishing processes. Improving the surface smoothness of the thin-film substrate eliminates bending problems caused by uneven heating during thick-film firing, such as shrinkage or expansion. Furthermore, the smoothed thin-film substrate can achieve good bonding with the thick-film sacrificial layers.

[0016] V. To improve processing precision, the surface circuit layer is finely processed using photolithography. Photolithography offers high precision, thus meeting the miniaturization requirements of high-density integration. Furthermore, the surface circuit layer utilizes thin-film technology, which creates a smooth and flat metal layer, solving the problems of low precision and uneven surface in thick-film processing. It also addresses issues such as heat generation, arcing between RF lines, and dielectric breakdown caused by significant losses during RF signal transmission under high-power signals.

[0017] 6. A molybdenum-copper layer is added to the bottom layer and connected to the metal casing. Heat dissipation holes are incorporated to facilitate system cooling. Furthermore, while each circuit layer is made of tungsten alloy, the casing is typically made of a heat-dissipating alloy. This difference in thermal expansion coefficients prevents a direct connection between the casing and the circuit layers. The introduction of the molybdenum-copper layer not only provides heat dissipation but also ensures a good connection with the casing, thus improving the overall connection between the system and the casing. Attached Figure Description

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will now be described in further detail with reference to the accompanying drawings.

[0019] Figure 1 A three-dimensional structural diagram of Embodiment 2 is shown.

[0020] Figure 2 A three-dimensional structural diagram and a channel connection diagram of Embodiment 2 are shown.

[0021] Figure 3 A three-dimensional structural diagram of the surface circuit layer in Embodiment 2 is shown.

[0022] Figure 4 A three-dimensional structural diagram of the second metal layer in Example 2 is shown.

[0023] Figure 5 A three-dimensional structural diagram of the fourth metal layer in Example 2 is shown.

[0024] Figure 6 A three-dimensional structural diagram of the fifth metal layer in Example 2 is shown.

[0025] Figure 7 The circuit diagram of the high-power switch in Embodiment 1 is shown.

[0026] Explanation of reference numerals in the attached figures: Surface circuit layer-1, driver-10, first RF transmission line-11, second RF transmission line-12, third RF transmission line-13, fourth RF transmission line-14, first PIN diode-15a, second PIN diode-15b, third PIN diode-15c, first capacitor-16a, second capacitor-16b, third capacitor-16c, fourth capacitor-16d, metal layer-3, first metal layer-30, second metal layer-31, third metal layer-32, fourth metal layer-33, fifth metal layer-34, sixth metal layer-35, first inductor-310, second inductor-311, third inductor-312, fourth inductor-313, first resistor-330, second resistor-331, first driver Driver control circuit-340, second driver control circuit-341, ceramic substrate-4, sacrificial layer-2, thin film substrate-20, thick film sacrificial layer-21, molybdenum copper layer-36, heat dissipation hole-5, first channel-60, second channel-61, third channel-64, fourth channel-63, fifth channel-62, sixth channel-70, seventh channel-71, eighth channel-72, ninth channel-73, tenth channel-82, twelfth channel-80, thirteenth channel-81, fourteenth channel-90, fifteenth channel-92, sixteenth channel-91, seventeenth channel-93, first ceramic substrate-40, second ceramic substrate-41, third ceramic substrate-42, fourth ceramic substrate-43, fifth ceramic substrate-44. Detailed Implementation

[0027] Example 1 like Figure 7 The diagram shows the circuit structure of a high-power switch. It is easy to see from the diagram that the high-power switch includes an input terminal P1, the other end of which is connected to an inductor L1, and the other end of the inductor L1 is grounded.

[0028] The other end of input terminal P1 is connected to PIN diode D1. The negative terminal of PIN diode D1 is connected to PIN diode D3. The positive terminal of PIN diode D3 is connected to capacitor C1. The other end of capacitor C1 is connected to output terminal P2.

[0029] The negative terminal of PIN diode D1 is also connected to inductor L2, the other end of inductor L2 is connected to resistor R1, and the other end of resistor R1 is connected to driver.

[0030] The other end of inductor L2 is connected to capacitor C2, the other end of which is grounded, and capacitor C2 is located between inductor L2 and resistor R1.

[0031] The positive terminal of PIN diode D3 is also connected to inductor L3, the other end of inductor L3 is grounded, and inductor L3 is located between PIN diode D3 and capacitor C1.

[0032] The other end of input terminal P1 is also connected to PIN diode D2. The negative terminal of PIN diode D2 is connected to capacitor C4. The other end of capacitor C4 is connected to output terminal P3.

[0033] The negative terminal of PIN diode D2 is also connected to inductor L4, and the other end of inductor L4 is connected to resistor R2. Resistor R2 is connected to the driver, and inductor L4 is located between capacitor C4 and PIN diode D2.

[0034] The other end of inductor L4 is connected to capacitor C3, the other end of which is grounded, and capacitor C3 is located between resistor R2 and inductor L4.

[0035] One end of the driver is grounded.

[0036] A high-power signal is input from input terminal P1, and the driver is used to control the on and off states of PIN diodes D1, D2, and D3.

[0037] For example, when the driver provides a -5V voltage, PIN diodes D1 and D3 are in the conducting state, while inductors L1, L2, and L3 block the high-frequency signal from passing through. Therefore, the signal can only be output from the output terminal P2 after being filtered by capacitor C1.

[0038] When the driver provides 36V, PIN diode D2 is turned on, and inductors L1 and L4 block high-frequency signals from passing through. Therefore, the signal can only be output from the lower output terminal P3 after being filtered by capacitor C4.

[0039] Capacitor C2 and resistor R1 form the matching circuit for the driver power supply on the upper side or the side where the output terminal P2 is located.

[0040] Capacitor C3 and resistor R2 are the matching circuits for the driver power supply circuit on the lower side or the side where the output terminal P3 is located.

[0041] Example 2 like Figures 1-2 As shown, a high-power switch design method based on a thick-film circuit board includes the following steps: Provide a surface circuit layer 1, such as Figure 3 As shown, the surface circuit layer 1 is provided with a driver 10, a first radio frequency transmission line 11, a second radio frequency transmission line 12, a third radio frequency transmission line 13, a fourth radio frequency transmission line 14, a first PIN diode 15a, a second PIN diode 15b, a third PIN diode 15c, a first capacitor 16a, a second capacitor 16b, a third capacitor 16c, and a fourth capacitor 16d.

[0042] Provide a sacrifice layer 2, such as Figure 1 As shown, the sacrificial layer 2 is disposed below the surface circuit layer 1 and above the first metal layer 30. The sacrificial layer 2 includes a thin film substrate 20, and at least one thick film sacrificial layer 21 is disposed below the thin film substrate 20. The thin film substrate 20 is disposed below the surface circuit layer 1, and the thick film sacrificial layer 21 is disposed above the first metal layer 30. The thin film substrate 20 is made of silicon nitride ceramic.

[0043] Provide multiple metal layers 3, such as Figure 1 As shown, the metal layer 3 includes at least a first metal layer 30, a second metal layer 31, a third metal layer 32, a fourth metal layer 33, a fifth metal layer 34, and a sixth metal layer 35.

[0044] like Figure 4 As shown, the second metal layer 31 is provided with a first inductor 310, a second inductor 311, a third inductor 312, and a fourth inductor 313.

[0045] like Figure 5 As shown, a first resistor 330 and a second resistor 331 are provided on the fourth metal layer 33.

[0046] like Figure 6 As shown, the fifth metal layer 34 is provided with a first driver control circuit 340 and a second driver control circuit 341.

[0047] A multilayer ceramic substrate 4 is provided, wherein a ceramic substrate 4 is sandwiched between two adjacent metal layers 3. Specifically, as shown... Figure 1 As shown, the ceramic substrate 4 includes a first ceramic substrate 40 disposed between a first metal layer 30 and a second metal layer 31. A second ceramic substrate 41 is disposed between a second metal layer 31 and a third metal layer 32. A third ceramic substrate 42 is disposed between a third metal layer 32 and a fourth metal layer 33. A fourth ceramic substrate 43 is disposed between a fourth metal layer 33 and a fifth metal layer 34.

[0048] In addition, such as Figure 1As shown, a molybdenum-copper layer 36 is provided below the sixth metal layer 35. Multiple heat dissipation holes 5 are provided on the surface circuit layer 1, passing through the molybdenum-copper layer 36. When the heat dissipation holes 5 pass through each ceramic substrate layer 4, they are connected via metal vias. When the heat dissipation holes 5 pass through each metal layer 3, they are connected via vias. By connecting the molybdenum-copper layer 36 to the metal casing and providing the heat dissipation holes 5 for heat dissipation, system heat dissipation is facilitated. Furthermore, each metal layer is made of tungsten alloy, while the casing is generally made of an alloy that facilitates heat dissipation. Therefore, the thermal expansion coefficients between the casing and each circuit layer are different, making direct connection between the casing and the circuit layers difficult. The introduction of the molybdenum-copper layer 36 not only provides heat dissipation but also ensures a good connection with the casing, thereby improving the connection between the system and the casing.

[0049] Specifically, this can be implemented using thin-film and thick-film processes. The surface circuit layer 1 is formed on the sacrificial layer 2 using a thin-film process. The first metal layer 30 is formed on the first ceramic substrate 40 using a thick-film process; the second metal layer 31 is formed on the second ceramic substrate 41 using a thick-film process; the third metal layer 32 is formed on the third ceramic substrate 42 using a thick-film process; the fourth metal layer 33 is formed on the fourth ceramic substrate 43 using a thick-film process; the fifth metal layer 34 is formed on the fifth ceramic substrate 44 using a thick-film process; and the sixth metal layer 35 is formed on the bottom surface of the fifth ceramic substrate 44 using a thick-film process. Then, corresponding components are placed on the corresponding layers, and then... Figure 1 The layers are stacked in the order shown and then fired to produce the product.

[0050] Combination Figures 1-6 Specifically, driver 10 is connected to first driver control circuit 340 and second driver control circuit 341 via first channel 60 and second channel 61, respectively. Driver 10 is also connected to first metal layer 30 via third channel 64. First driver control circuit 340 and second driver control circuit 341 are connected to surface circuit layer 1 via fourth channel 63 and fifth channel 62, respectively.

[0051] Specifically, the first RF transmission line 11 is connected to the first inductor 310 via the sixth channel 70. The second RF transmission line 12 is connected to the third inductor 312 via the seventh channel 71. The third RF transmission line 13 is connected to the fourth inductor 313 via the eighth channel 72. The fourth RF transmission line 14 is connected to the second inductor 311 via the ninth channel 73.

[0052] Specifically, the first inductor 310 is connected to the third metal layer 32 through the tenth channel 82. The third inductor 312 is connected to the third metal layer 32 through the eleventh channel. The fourth inductor 313 is connected to the third metal layer 32 through the twelfth channel 80. The second inductor 311 is connected to the third metal layer 32 through the thirteenth channel 81.

[0053] Specifically, the second resistor 331 is connected to the surface circuit layer 1 through the fourteenth channel 90 and the fifteenth channel 92. The first resistor 330 is connected to the surface circuit layer 1 through the sixteenth channel 91 and the seventeenth channel 93.

[0054] Channels 60, 61, 64, 63, 62, 70, 71, 72, 73, 82, 80, 90, 91, 82, 92, 83, 90, 92, 93, 91, 92, 92, 93, 92, 94, 95, 92, 96, and 97 are connected via vias when passing through each metal layer 3. When the above channels pass through each ceramic substrate 4 and sacrificial layer 2, they are connected via metal vias.

[0055] The driver 10 is the driver mentioned in Example 1.

[0056] The first PIN diode 15a is the PIN diode D1 mentioned in Example 1, the second PIN diode 15b is the PIN diode D2 mentioned in Example 1, and the third PIN diode 15c is the PIN diode D3 mentioned in Example 1.

[0057] The first capacitor 16a is the capacitor C1 mentioned in Example 1, the second capacitor 16b is the capacitor C2 mentioned in Example 1, the third capacitor 16c is the capacitor C3 mentioned in Example 1, and the fourth capacitor 16d is the capacitor C4 mentioned in Example 1.

[0058] The first inductor 310 is the inductor L1 mentioned in Embodiment 1, the second inductor 311 is the inductor L2 mentioned in Embodiment 1, the third inductor 312 is the inductor L3 mentioned in Embodiment 1, and the fourth inductor 313 is the inductor L4 mentioned in Embodiment 1.

[0059] The first resistor 330 is the resistor R1 mentioned in Example 1, and the second resistor 331 is the resistor R2 mentioned in Example 1.

[0060] The first metal layer 30 is the ground layer of the driver 10.

[0061] The third metal layer 32 serves as the grounding layer for the first inductor 310, the second inductor 311, the third inductor 312, and the fourth inductor 313.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include these modifications and variations.

Claims

1. A high-power switch design method based on a thick thin-film circuit board, characterized in that, include: A surface circuit layer (1) is provided, on which a driver (10), a first radio frequency transmission line (11), a second radio frequency transmission line (12), a third radio frequency transmission line (13), a fourth radio frequency transmission line (14), a first PIN diode (15a), a second PIN diode (15b), a third PIN diode (15c), a first capacitor (16a), a second capacitor (16b), a third capacitor (16c), and a fourth capacitor (16d) are disposed. A multilayer metal layer (3) is provided, the metal layer (3) including at least a first metal layer (30), a second metal layer (31), a third metal layer (32), a fourth metal layer (33), a fifth metal layer (34) and a sixth metal layer (35); a first inductor (310), a second inductor (311), a third inductor (312) and a fourth inductor (313) are provided on the second metal layer (31); a first resistor (330) and a second resistor (331) are provided on the fourth metal layer (33); A first driver control circuit (340) and a second driver control circuit (341) are disposed on the fifth metal layer (34). A multilayer ceramic substrate (4) is provided, wherein a ceramic substrate (4) is sandwiched between two adjacent layers of a metal layer (3). A sacrificial layer (2) is also provided, which is disposed below the surface circuit layer (1) and above the first metal layer (30); The sacrificial layer (2) includes a thin film substrate (20), and at least one thick film sacrificial layer (21) is provided on the lower side of the thin film substrate (20). The thin film substrate (20) is located on the lower side of the surface circuit layer (1), and the thick film sacrificial layer (21) is located on the upper side of the first metal layer (30). The thin film substrate (20) is made of silicon nitride ceramic. A molybdenum-copper layer (36) is also provided on the underside of the sixth metal layer (35).

2. The high-power switch design method based on a thick thin-film circuit board according to claim 1, characterized in that, Multiple heat dissipation holes (5) are provided on the surface circuit layer (1), and the heat dissipation holes (5) penetrate through the molybdenum copper layer (36).

3. The high-power switch design method based on a thick thin-film circuit board according to claim 1, characterized in that, The driver (10) is connected to the first driver control circuit (340) and the second driver control circuit (341) through the first channel (60) and the second channel (61), respectively; The driver (10) is also connected to the first metal layer (30) via a third channel (64); The first driver control circuit (340) and the second driver control circuit (341) are connected to the surface circuit layer (1) through the fourth channel (63) and the fifth channel (62), respectively.

4. The high-power switch design method based on a thick thin-film circuit board according to claim 1, characterized in that, The first radio frequency transmission line (11) is connected to the first inductor (310) through the sixth channel (70); The second radio frequency transmission line (12) is connected to the third inductor (312) through the seventh channel (71); The third radio frequency transmission line (13) is connected to the fourth inductor (313) through the eighth channel (72); The fourth radio frequency transmission line (14) is connected to the second inductor (311) through the ninth channel (73).

5. The high-power switch design method based on a thick thin-film circuit board according to claim 1, characterized in that, The first inductor (310) is connected to the third metal layer (32) through the tenth channel (82); The third inductor (312) is connected to the third metal layer (32) through the eleventh channel; The fourth inductor (313) is connected to the third metal layer (32) through the twelfth channel (80); The second inductor (311) is connected to the third metal layer (32) through the thirteenth channel (81).

6. The high-power switch design method based on a thick thin-film circuit board according to claim 1, characterized in that, The second resistor (331) is connected to the surface circuit layer (1) through the fourteenth channel (90) and the fifteenth channel (92); The first resistor (330) is connected to the surface circuit layer (1) through the sixteenth channel (91) and the seventeenth channel (93).

7. The high-power switch design method based on a thick thin-film circuit board according to claim 1, characterized in that, The ceramic substrate (4) includes a first ceramic substrate (40) disposed between a first metal layer (30) and a second metal layer (31). A second ceramic substrate (41) is provided between the second metal layer (31) and the third metal layer (32). A third ceramic substrate (42) is provided between the third metal layer (32) and the fourth metal layer (33). A fourth ceramic substrate (43) is provided between the fourth metal layer (33) and the fifth metal layer (34). A fifth ceramic substrate (44) is provided between the fifth metal layer (34) and the sixth metal layer (35).

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