Gallium nitride switching device, switching tube and electronic device

Abstract

The present application discloses a gallium nitride switching device, a switching tube and an electronic device. The switching device includes a gallium nitride transistor and a switching tube; the switching tube is connected to the gallium nitride transistor to control the gallium nitride transistor; the gallium nitride switching device further includes a gate, a drain, a switching device current sampling terminal and a grounding portion; the switching device current sampling terminal is used to collect the current of the switching device; the grounding portion is used to commonly connect the gallium nitride transistor and the switching tube to ground. The switching tube includes a gate, a drain, a switching device current sampling terminal and a grounding portion; the switching device current sampling terminal is used to collect the current of the switching tube; the grounding portion is used to connect the switching tube to ground. The electronic device includes the switching device. The present application can improve the switching speed of the electronic device, improve the reliability and reduce the power consumption caused by an external current sampling resistor, and can further improve the efficiency.

Description

Technical Field

[0001] This application relates to the technical field of switching devices, and particularly to a gallium nitride switching device, a switching tube, and an electronic device. Background Art

[0002] In power electronic and electrical equipment, efficient power conversion is an important means to achieve environmental protection and energy conservation. Efficient power conversion is achieved through efficient switching devices. Since the emergence of silicon transistors, people have been constantly looking for more efficient switching devices; especially now in the 5G era, high efficiency and high power density are the development trends of modern switching power supplies. Increasing the switching frequency can effectively reduce the size of passive devices. The performance of traditional silicon (Si)-based power devices has gradually reached a bottleneck. From transistors based on silicon such as BJT (Bipolar Junction Transistor), MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), IGBT (Insulated Gate Bipolar Transistor), and diodes, to the current increasingly developed switching devices based on the third-generation wide bandgap semiconductor material gallium nitride (GaN), the gallium nitride power devices in the third-generation gallium nitride devices with wide bandgap semiconductor devices have a smaller on-resistance than MOSFETs based on silicon materials and can withstand higher switching frequencies. Gallium nitride has properties such as a wide direct bandgap, strong atomic bonds, high thermal conductivity, high chemical stability (almost not corroded by any acid), and strong anti-radiation ability, etc., and has broad prospects in the applications of optoelectronics, high-temperature high-power devices, and high-frequency microwave devices.

[0003] Currently, there are mainly three types of gallium nitride devices: sapphire-based gallium nitride devices with sapphire as the substrate, gallium nitride devices with silicon carbide (SiC) as the substrate, and silicon-based gallium nitride devices with silicon as the substrate. Among them, silicon-based gallium nitride devices have attracted much attention due to their low-cost advantage; however, due to the hetero-structure of silicon and gallium nitride, the reliability and yield are limited, so they have not been applied in large-scale production; in addition, the cost of silicon-based gallium nitride devices is also much higher than that of traditional silicon-based devices.

[0004] Currently, gallium nitride devices mainly focus on enhancement-mode gallium nitride devices and cascode gallium nitride devices. The enhancement-mode gallium nitride device simply controls the drain-source by directly applying a voltage to the gate. The cascode gallium nitride device is a junction field-effect transistor (JFET) gallium nitride device in series with a low-voltage MOSFET transistor; by controlling the on and off of the low-voltage MOSFET transistor, the drain-source can be controlled. The reliability of the cascode gallium nitride device is relatively high.

[0005] Figure 1 is a structural diagram of a typical gallium nitride device currently. The gallium nitride device (gallium nitride transistor) is connected in series with a low-voltage N-type MOSFET transistor (NMOS transistor). Refer to Figure 2 where the NMOS transistor is a vertical structure MOS transistor, and the source needs to be connected to the port through a via and then connected in the form of wire bonding.

[0006] Figure 3 shows the structure of a typical cascode gallium nitride device.

[0007] Figure 4 shows a typical application circuit of a gallium nitride device. In the figure is a typical flyback circuit topology. The PWM (pulse width modulation) controller drives the switching device through the signal output by its gate; among them, the switching device is a gallium nitride device. The gallium nitride device includes a gate G, a drain D, and a source S; the drain D is connected to the transformer T1; the gate G of the gallium nitride device is connected to the gate G of the PWM controller; the source S of the gallium nitride device is connected to a current sampling resistor and then to the current sampling pin Isense of the PWM controller, and the pin Vcc of the PWM controller provides the power required by the PWM controller.

[0008] The disclosure of the above background technical content is only used to assist in understanding the inventive concept and technical solution of the present application, and it does not necessarily belong to the prior art of the present application. Without clear evidence indicating that the above content was publicly available on the filing date of the present application, the above background technology should not be used to evaluate the novelty and inventiveness of the present application. Summary of the Invention

[0009] The present application proposes a gallium nitride switching device, a switching tube, and an electronic device, which can avoid the power consumption brought by an external current sampling resistor and improve the efficiency of the device.

[0010] In a first aspect, the present application provides a gallium nitride switching device, including a gallium nitride transistor and a switching transistor;

[0011] The switching transistor is connected to the gallium nitride transistor to control the gallium nitride transistor;

[0012] The gallium nitride switching device further includes a gate, a drain, a switching device current sampling terminal, and a grounding portion;

[0013] The switching device current sampling terminal is used to collect the current of the switching device;

[0014] The grounding portion commonly connects the gallium nitride transistor and the switching transistor to ground.

[0015] In some preferred embodiments, the grounding portion is a grounding substrate; the gallium nitride transistor and the switching transistor are both disposed on the grounding substrate and are both connected to the grounding substrate.

[0016] In some preferred embodiments, the fact that the gallium nitride transistor and the switching transistor are both disposed on the grounding substrate and are both connected to the grounding substrate specifically means that: the gate of the gallium nitride transistor is located at the bottom of the substrate, the substrate of the gallium nitride transistor is connected to the grounding substrate, and the substrate of the switching transistor is connected to the grounding substrate.

[0017] In some preferred embodiments, the gallium nitride switching device further includes a gate pin, a drain pin, a switching device current sampling pin, and a grounding pin;

[0018] The gate pin is connected to the gate of the gallium nitride switching device;

[0019] The drain pin is connected to the drain;

[0020] The switching device current sampling pin is connected to the switching device current sampling terminal;

[0021] The grounding pin is connected to the grounding portion.

[0022] In some preferred embodiments, a first conduction channel can be formed between the source and the drain of the switching transistor;

[0023] A second conduction channel can be formed between the source and the drain of the gallium nitride transistor;

[0024] The first conduction channel can be in conduction with the second conduction channel;

[0025] The switching device current sampling terminal can be in conduction with the first conduction channel and the second conduction channel.

[0026] In some preferred embodiments, the conduction of the first conduction channel with the second conduction channel is specifically as follows: the drain of the switching transistor is connected to the source of the gallium nitride transistor.

[0027] In some preferred embodiments, the conduction of the switching device current sampling terminal with the first conduction channel and the second conduction channel is specifically as follows: the switching device current sampling terminal is the source of the switching transistor, and the switching device current sampling pin is wire-bonded to the source of the switching transistor.

[0028] In some preferred embodiments, the gate of the gallium nitride switching device is the gate of the switching transistor; the gate of the switching transistor is wire-bonded to the gate pin;

[0029] The drain of the gallium nitride switching device is the drain of the gallium nitride transistor; the drain of the gallium nitride transistor is wire-bonded to the drain pin.

[0030] In some preferred embodiments, the switching transistor is a MOSFET transistor; the MOSFET transistor is an N-channel MOSFET transistor; the N-channel MOSFET transistor is a planar MOSFET transistor.

[0031] In a second aspect, the present application provides a switching transistor, including a gate, a drain, a switching device current sampling terminal, and a grounding portion;

[0032] The switching device current sampling terminal is used to collect the current of the switching transistor;

[0033] The grounding portion is connected to the substrate of the switching transistor and is used to connect the switching transistor to the ground.

[0034] In some preferred embodiments, an internal resistor is connected between the drain and the grounding portion.

[0035] In some preferred embodiments, the grounding portion is a grounding substrate; the switching device current sampling terminal is the source of the switching transistor; or, the drain is connected to the source of the switching transistor, and the switching device current sampling terminal is the source of the switching transistor.

[0036] In some preferred embodiments, the specific forms of the switching transistor include gallium nitride transistors and MOSFET transistors.

[0037] In some preferred embodiments, the MOSFET transistor is an N-channel MOSFET transistor; the N-channel MOSFET transistor is a planar MOSFET transistor.

[0038] In a third aspect, the present application provides an electronic device, including the above-mentioned gallium nitride switching device.

[0039] In some preferred embodiments, the electronic device further includes a pulse width modulation controller having a gate; the gate is used to connect to the gate of the pulse width modulation controller.

[0040] Compared with the prior art, the beneficial effects of the present application are as follows:

[0041] In the gallium nitride switching device of the embodiment of the present application, the gallium nitride transistor and the switching transistor of the gallium nitride switching device are commonly connected to the ground through the grounding portion, without the need for vias, which can reduce the electromagnetic interference caused by the stray inductance generated thereby, can increase the switching frequency and improve the reliability of the device; the gallium nitride switching device of this embodiment has a built-in switching device current sampling terminal, without the need for a current sampling resistor, which can avoid the power consumption caused by the current sampling resistor and can further improve the efficiency of the device. It can be seen that the structure of the gallium nitride switching device in this embodiment is simpler, which can make the control of the pulse width modulation controller more flexible, can improve the accuracy of current sampling, and can increase the switching speed of the electronic device. Description of the Drawings

[0042] Figure 1 is a structural diagram of a typical gallium nitride device;

[0043] Figure 2 shows Figure 1 the cross-sectional structure of the gallium nitride device;

[0044] Figure 3 shows the structure of a typical cascaded gallium nitride device;

[0045] Figure 4 shows a typical application circuit of a gallium nitride device;

[0046] Figure 5 shows the cross-sectional structure of the gallium nitride device of the first embodiment of the present application;

[0047] Figure 6 shows the package structure of the gallium nitride device of the first embodiment of the present application;

[0048] Figure 7 shows the package structure of the gallium nitride device of the first embodiment of the present application;

[0049] Figure 8 shows the cross-sectional structure of the switching transistor of the first embodiment of the present application;

[0050] Figure 9 shows the circuit structure of the electronic device of the second embodiment of the present application;

[0051] Figure 10Shows a switching transistor with a drain connected to a ground resistor in the third embodiment of the application. Detailed implementation mode

[0052] In order to make the technical problems, technical solutions and beneficial effects to be solved by the embodiments of the present application clearer, the following combines Figures 1 to 10 and embodiments to further describe the present application in detail. It should be understood that the specific embodiments described here are only used to explain the present application and are not used to limit the present application.

[0053] It should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0054] The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0055] First embodiment

[0056] This embodiment provides a gallium nitride switching device. Refer to Figure 6 , the gallium nitride switching device 10 includes a gallium nitride transistor 100 and a switching transistor 200 packaged together.

[0057] In this embodiment, the switching transistor 200 is a MOSFET transistor, specifically an N-channel MOSFET transistor (or an N-type MOSFET transistor); in other embodiments, the switching transistor 200 can also be other types of transistors.

[0058] Refer to Figure 6 , the switching transistor 200 is connected to the gallium nitride transistor 100 to control the gallium nitride transistor 100. Specifically, the switching transistor 200 is in series with the gallium nitride transistor 100. A conduction channel can be formed between the switching transistor 200 and the gallium nitride transistor 100, thereby generating current.

[0059] The gallium nitride switching device 10 of this embodiment is provided with a gate 101, a drain 102, a switching device current sampling terminal 103, and a grounding portion 104.

[0060] Refer to Figure 5, the gallium nitride transistor 100 has a gate, a source, and a drain. The switching transistor 200 also has a gate, a source, and a drain.

[0061] The gate 101 can receive a gate drive signal to drive the gallium nitride switching device 10. In this embodiment, the gate 101 is the gate of the switching transistor 200.

[0062] The drain 102 is the drain of the gallium nitride transistor 100; the drain 102 is used to connect to the winding of the transformer T1.

[0063] The switching device current sampling terminal 103 is used to collect the current of the gallium nitride switching device 10. In this embodiment, the switching device current sampling terminal 103 is the source of the switching transistor 200; in other embodiments, the switching device current sampling terminal 103 is a component built into the gallium nitride switching device 10 and connected to the source of the switching transistor 200. After the gate 101 of the gallium nitride switching device 10 receives the drive signal, the switching transistor 200 and the gallium nitride transistor 100 are turned on. A first conduction channel can be formed between the source and the drain of the switching transistor 200 to generate current; a second conduction channel can also be formed between the source and the drain of the gallium nitride transistor 100; since the switching transistor 200 and the gallium nitride transistor 100 are connected in series, specifically, the drain of the switching transistor 200 is connected to the source of the gallium nitride transistor 100, so the first conduction channel and the second conduction channel are conducted; the source of the switching transistor 200, which is the switching device current sampling terminal 103, can also be conducted with the first conduction channel and the second conduction channel, so as to realize collecting the current of the gallium nitride switching device 10.

[0064] The grounding part 104 is used to commonly connect the gallium nitride transistor 100 and the switching transistor 200 to the ground GND. In this embodiment, the grounding part is a grounding substrate; specifically, the gallium nitride transistor 100 and the switching transistor 200 are both placed on the grounding substrate 104 and are both directly connected to the grounding substrate 104, thereby realizing grounding. In this embodiment, the gate of the gallium nitride transistor 100 is located at the bottom of the substrate 110, and the substrate 110 of the gallium nitride transistor 100 is connected to the grounding substrate 104, so that the gallium nitride transistor 100 is directly connected to the grounding substrate 104; the substrate 210 of the switching transistor 200 is connected to the grounding substrate 104, so that the switching transistor 200 is directly connected to the grounding substrate 104; the grounding substrate 104 is connected to the ground, so that the gallium nitride transistor 100 and the switching transistor 200 are commonly connected to the ground. In other implementations, the grounding part 104 is other components that can commonly connect the gallium nitride transistor 100 and the switching transistor 200 to the ground GND, such as terminals.

[0065] Reference Figure 6 and Figure 7After the gallium nitride switching device of this embodiment is encapsulated, it has a gate pin 11, a drain pin 12, a switching device current sampling pin 13, and a ground pin 14.

[0066] The gate pin 11 is connected to the gate of the gallium nitride switching device 10, specifically to the gate of the switching transistor 200. In this embodiment, the gate of the switching transistor 200 is connected to the gate pin 11 by wire bonding. In this way, a gate drive signal is input to the gate of the switching transistor 200 through the gate pin 11.

[0067] The drain pin 12 is connected to the drain 102. In this embodiment, the drain pin 12 is connected to the drain of the gallium nitride transistor 100; the drain of the gallium nitride transistor 100 is connected to the drain pin 12 by wire bonding.

[0068] The switching device current sampling pin 13 is connected to the switching device current sampling terminal 103, specifically to the source of the switching transistor 200. In this embodiment, the switching device current sampling pin 13 is connected to the source of the switching transistor 200 by wire bonding. During use, the switching device current sampling pin 13 will be connected to the current sampling pin Isense of the pulse width modulation controller 20, so as to input the current of the gallium nitride switching device 10 collected into the pulse width modulation controller 20.

[0069] The ground pin 14 is connected to the ground substrate 104. During use, the ground pin 14 will be connected to the ground, so that the gallium nitride transistor 100 and the switching transistor 200 are jointly connected to the ground.

[0070] According to actual needs, multiple drain pins 12 and ground pins 14 can be set, such as setting two, three, four, five or more than six drain pins 12 and ground pins 14.

[0071] Reference Figure 6 and Figure 9 In this embodiment, the pulse width modulation controller 20 outputs a gate drive signal to the gate pin 11, and the drain and source of the switching transistor 200 are turned on; since the source of the gallium nitride transistor 100 is connected to the drain of the switching transistor 200, and the gate of the gallium nitride transistor 100 is connected to the ground through the ground substrate 104, then the gallium nitride transistor 100 is turned on, so that a current is formed inside the gallium nitride switching device 10. The current of the gallium nitride switching device 10 is transmitted to the switching device current sampling pin 13 through the built-in switching device current sampling terminal 103, and then enters the current sampling pin Isense of the pulse width modulation controller 20. In this way, the gallium nitride switching device 10 can be controlled by sampling the current.

[0072] As described above, the present embodiment proposes a novel structure of a switching device (such as a MOSFET transistor). Compared with the traditional switching device: Refer to Figure 8 , the switching device 200 of the present embodiment includes a gate 101, a drain 102, a switching device current sampling terminal 103, and a grounding portion 104; the drain 102 is the drain of the switching device 200; the switching device current sampling terminal 103 is used to collect the current of the switching device 200; the switching device current sampling terminal 103 is connected to the source of the switching device 200, or the source of the switching device 200 directly serves as the switching device current sampling terminal 103, so as to achieve built-in current sampling; the substrate 210 of the switching device 200 is directly connected to the grounding portion 104 without the need for a via (VIA). The switching device 200 of the present embodiment can be a gallium nitride transistor or a MOSFET transistor. Compared with the traditional switching device architecture, both the gallium nitride transistor 100 and the switching device 200 of the gallium nitride switching device of the present embodiment are directly placed on the grounding substrate 104 without the need for a via (VIA), which can reduce the electromagnetic interference caused by the stray inductance generated thereby and can increase the switching frequency; the gallium nitride switching device 10 of the present embodiment has a built-in switching device current sampling terminal 103 without the need for a current sampling resistor, which can avoid the power consumption caused by the current sampling resistor and can improve the efficiency of the device. It can be seen that the structure of the gallium nitride switching device of the present embodiment is simpler, the control of the PWM controller is more flexible, the accuracy of current sampling can be improved, and the switching speed of the electronic device can be increased.

[0073] Second Embodiment

[0074] Refer to Figure 9 , the present embodiment provides an electronic device including the above-mentioned gallium nitride switching device 10. The drain pin 102 of the gallium nitride switching device 10 is connected to the transformer T1.

[0075] The electronic device of the present embodiment further includes a pulse width modulation controller 20. The pulse width modulation controller 20 can be connected to the gate 101 of the gallium nitride switching device 10 to drive the gallium nitride switching device 10. In the present embodiment, the electronic device is a switching power supply.

[0076] Third Embodiment

[0077] Refer to Figure 10 , the switching device 200 of the present embodiment is provided with a built-in resistor R0. One end of the built-in resistor R0 is connected to the drain of the switching device 200, and the other end of the built-in resistor R0 is connected to the grounding portion 104; that is to say, the built-in resistor R0 serves as the built-in grounding resistor of the switching device 200. The built-in resistor R0 as the grounding resistor can provide a drain current path and can suppress the instantaneous peak voltage, thereby improving the reliability.

[0078] The above content is a further detailed description of the present application in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present application is only limited to these descriptions. For those of ordinary skill in the technical field to which the present application pertains, without departing from the concept of the present application, several alternatives or modifications can be made to these described embodiments, and these alternative or modified forms should all be regarded as falling within the protection scope of the present application.

Claims

1. A gallium nitride switching device, characterized in that: It includes a gallium nitride transistor and a switching transistor, and the switching transistor is a MOSFET transistor; The switching transistor is connected to the gallium nitride transistor to control the gallium nitride transistor; The gallium nitride switching device further includes a gate, a drain, a switching device current sampling terminal, and a grounding part; The switching device current sampling terminal is used to collect the current of the gallium nitride switching device; The grounding part is used to commonly connect the gallium nitride transistor and the switching transistor to the ground; The grounding part is a grounding substrate; The gallium nitride transistor and the switching transistor are both placed on the grounding substrate. The gate of the gallium nitride transistor is located at the bottom of the substrate. The bottom of the substrate of the gallium nitride transistor and the gate of the gallium nitride transistor are connected to the grounding substrate, and the substrate of the switching transistor is connected to the grounding substrate.

2. The gallium nitride switching device according to claim 1, wherein: The gallium nitride switching device further includes a gate pin, a drain pin, a switching device current sampling pin, and a grounding pin; The gate pin is connected to the gate of the gallium nitride switching device; The drain pin is connected to the drain; The switching device current sampling pin is connected to the switching device current sampling terminal; The grounding pin is connected to the grounding part.

3. The gallium nitride switching device according to claim 2, characterized in that: A first conduction channel can be formed between the source and the drain of the switching transistor; A second conduction channel can be formed between the source and the drain of the gallium nitride transistor; The drain of the switching transistor is connected to the source of the gallium nitride transistor to make the first conduction channel and the second conduction channel conduct; The switching device current sampling terminal can be conducted with the first conduction channel and the second conduction channel.

4. The gallium nitride switching device according to claim 3, characterized in that The switching device current sampling terminal can be conducted with the first conduction channel and the second conduction channel specifically as: the switching device current sampling terminal is the source of the switching transistor, and the switching device current sampling pin is connected to the source of the switching transistor by wire bonding.

5. The gallium nitride switching device according to claim 2, characterized in that: The gate of the gallium nitride switching device is the gate of the switching transistor; the gate of the switching transistor is connected to the gate pin by wire bonding; The drain of the gallium nitride switching device is the drain of the gallium nitride transistor; the drain of the gallium nitride transistor is connected to the drain pin by wire bonding; The MOSFET transistor is an N-channel MOSFET transistor; the N-channel MOSFET transistor is a planar-structured MOSFET transistor.

6. An electronic device, characterized in that: It includes the gallium nitride switching device according to any one of claims 1 to 5.

Images