MOS structure for automobile starting, manufacturing method and automobile starting system

Abstract

The application relates to a MOS structure for automobile starting, a manufacturing method and an automobile starting system, which comprises a base island, a first MOS tube and a second MOS tube arranged on the base island, and a plastic sealing body for sealing the base island, the first MOS tube and the second MOS tube, the gate of the first MOS tube is connected with the gate of the second MOS tube, and the drain of the first MOS tube is connected with the drain of the second MOS tube. The application has the effects of saving space, reducing cost and reducing internal resistance.

Description

Technical Field

[0001] This application relates to the field of automotive emergency starting technology, and in particular to a MOS structure, manufacturing method, and automotive starting system for automotive starting. Background Technology

[0002] Cars bring great convenience to people's travel, but they cannot start under certain special circumstances, causing great trouble for users. Therefore, emergency jump starters are used, and the switching transistors of emergency jump starters are generally large relays or MOSFETs.

[0003] Currently, in practical applications, each MOS is usually packaged separately and connected to pins. Then, two packaged MOS switches are connected in series back-to-back on the PCB board. However, products manufactured in this way are large in size, have high internal resistance, and are expensive. This needs to be improved. Summary of the Invention

[0004] To address the issues of large product size and high cost, this application provides a MOS structure for automobile starting, a manufacturing method, and an automobile starting system.

[0005] In the first aspect, this application provides a MOS structure for automotive starting, employing the following technical solution:

[0006] A MOS structure for automotive starting includes a base island, a first MOS transistor and a second MOS transistor disposed on the base island, and a plastic encapsulation that seals the base island, the first MOS transistor, and the second MOS transistor. The gate of the first MOS transistor is connected to the gate of the second MOS transistor, and the drain of the first MOS transistor is connected to the drain of the second MOS transistor.

[0007] By adopting the above technical solution, two MOSFETs are packaged together, with the two gates connected and the two drains connected. This eliminates the need to package a single MOSFET separately, allowing the packaged MOSFET to be directly applied to automotive starting systems without the need for back-to-back soldering, thus saving space and packaging costs.

[0008] Optionally, the gate of the first MOSFET and the gate of the second MOSFET, as well as the drain of the first MOSFET and the drain of the second MOSFET, are connected by connecting lines.

[0009] By adopting the above technical solution, the gates of the two MOS transistors on the base island are connected by a connecting line, and the drains of the two MOS transistors are connected by a connecting line, thereby realizing the packaging of two separate MOS transistors together.

[0010] Optionally, the first MOS transistor includes a first P-type substrate, a first N-type trench, a second N-type trench, a first oxide layer, a first gate metal layer, a first drain extension layer, a first source metal layer, and a first insulating layer. One side of the first P-type substrate is fixed to the base island. The first N-type trench is formed on the side of the first P-type substrate away from the base island to form a first source region. The second N-type trench is formed on the side of the first P-type substrate away from the base island to form a first drain region. The first oxide layer covers the side of the first P-type substrate away from the base island. The first source metal layer is connected to the first source region. The first drain extension layer is connected to the first drain region. The first insulating layer is disposed between the first source metal layer and the first drain extension layer. The first gate metal layer is disposed on the first insulating layer.

[0011] The second MOS transistor includes a second P-type substrate, a third N-type trench, a fourth N-type trench, a second oxide layer, a second gate metal layer, a second drain extension layer, a second source metal layer, and a second insulating layer. One side of the second P-type substrate is fixed to the base island. The third N-type trench is formed on the side of the second P-type substrate away from the base island to form a second source region. The fourth N-type trench is formed on the side of the second P-type substrate away from the base island to form a second drain region. The second oxide layer covers the side of the second P-type substrate away from the base island. The second source metal layer is connected to the second source region. The second drain extension layer is connected to the second drain region. The second insulating layer is disposed between the second source metal layer and the second drain extension layer. The second gate metal layer is disposed on the second insulating layer.

[0012] The first drain extension layer and the second drain extension layer are integrally formed.

[0013] By adopting the above technical solution, the first MOSFET and the second MOSFET are processed into a single unit before packaging. The first drain extension layer and the second drain extension layer are connected. The two drains can be connected together without connecting wires, simplifying the subsequent packaging process and realizing the packaging of two MOSFETs. This allows the packaged MOSFETs to be directly applied to automotive starting systems.

[0014] Optionally, the first gate metal layer and the second gate metal layer are integrally formed.

[0015] By adopting the above technical solution, there is no need to use connecting wires to connect the first gate metal layer and the second gate metal layer, which simplifies the packaging process.

[0016] Optionally, both the first insulating layer and the second insulating layer are made of silicon dioxide or borosilicate glass.

[0017] By adopting the above technical solution, using silicon dioxide or borosilicate glass as an insulating layer, the gate and source, and the gate and drain of the MOS transistor are effectively isolated.

[0018] Optionally, it also includes a first lead, a second lead, and a control pin, wherein the source of the first MOSFET is connected to the first lead, the source of the second MOSFET is connected to the second lead, and the gate of the first MOSFET is connected to the control pin.

[0019] By adopting the above technical solution, the two MOSFETs are packaged and then led out with three leads, which reduces the internal resistance and ensures that the car can start normally.

[0020] Secondly, this application provides a method for manufacturing a MOS for automobile starting, which adopts the following technical solution:

[0021] A method for fabricating a MOS for automotive starting includes sequentially forming a first source region, a first drain region, a second source region, and a second drain region on a P-type substrate; depositing an oxide layer on the surface of the P-type substrate, aligning and patterning the first source region, the first drain region, the second source region, and the second drain region on the oxide layer, and depositing metal to form a first source metal layer, a first drain extension layer, a second source metal layer, and a second drain extension layer, wherein the first drain extension layer and the second drain extension layer are integrally formed; depositing metal on the oxide layer between the first source metal layer and the first drain extension layer to form a first gate metal layer, and depositing metal on the oxide layer between the second source metal layer and the second drain extension layer to form a second gate metal layer, wherein the first gate metal layer and the second gate metal layer are integrally formed.

[0022] By adopting the above technical solution, when patterning and depositing metal on the first source region, first drain region, second source region and second drain region on the oxide layer during the MOS forming process, the first drain extension plate and the second drain extension plate are formed together, and the first gate metal layer and the second gate metal layer are formed together. That is, the drain of the first MOS transistor and the drain of the second MOS transistor, and the first gate metal layer and the second gate metal layer are already connected during the forming process. Only packaging is required afterward, which reduces internal resistance and saves space.

[0023] Optionally, the method further includes: depositing an insulating dielectric between the first gate metal layer and the oxide layer to form a first insulating layer; and depositing an insulating dielectric between the second gate metal layer and the oxide layer to form a second insulating layer.

[0024] By adopting the above technical solution, the first insulating layer and the second insulating layer are used to isolate the gate and source, and the gate and drain of the MOS transistor.

[0025] Thirdly, this application provides an automotive starting system, which adopts the following technical solution:

[0026] An automotive starting system includes a MOS structure for starting a vehicle, a power module, and an automotive starter motor and control unit as described above. The positive terminal of the power module is electrically connected to the source of the first MOS transistor, and the negative terminal of the power module is electrically connected to the source of the second MOS transistor. The automotive starter motor and control unit are connected to the power module, and the control terminal of the automotive starter motor and control unit is connected to the gate of the first MOS transistor. The automotive starter motor and control unit is used to control the conduction state of the MOS structure.

[0027] By adopting the above technical solution, the conduction state of the MOS structure is controlled by the car starter motor and control unit, ensuring successful car starting and saving the space occupied by the MOS structure.

[0028] In summary, this application includes at least the following beneficial technical effects:

[0029] 1. By packaging two MOSFETs together, with the two gates connected and the two drains connected, there is no need to package a separate MOSFET. This allows the packaged MOSFET to be directly used in automotive starting systems without the need for back-to-back soldering, saving space and packaging costs.

[0030] 2. By connecting the two gates and two drains with connecting wires, two separate MOSFETs can be packaged together;

[0031] 3. Before packaging, the first MOSFET and the second MOSFET are processed into a single unit. The first drain extension layer and the second drain extension layer are connected. The two drains can be connected together without the need for connecting wires, which simplifies the subsequent packaging process and realizes the packaging of two MOSFETs. This allows the packaged MOSFETs to be directly used in automotive starting systems. Attached Figure Description

[0032] Figure 1 This is a perspective view of the packaging structure of Embodiment 1 of this application;

[0033] Figure 2 This is a cross-sectional schematic diagram of the packaging structure of Embodiment 1 of this application;

[0034] Figure 3 This is a perspective view of the packaging structure in Embodiment 2 of this application;

[0035] Figure 4 yes Figure 3 A cross-sectional schematic diagram of the packaging structure;

[0036] Figure 5This is a perspective view of another packaging structure in Embodiment 2 of this application;

[0037] Figure 6 yes Figure 5 A cross-sectional schematic diagram of the packaging structure;

[0038] Figure 7 This is a schematic diagram of the vehicle starting system of this application.

[0039] Explanation of reference numerals in the attached figures: 10, base island; 20, first MOSFET; 21, first P-type substrate; 22, first N-type trench; 23, second N-type trench; 24, first oxide layer; 25, first gate metal layer; 26, first drain extension layer; 27, first source metal layer; 28, first insulating layer; 30, second MOSFET; 31, second P-type substrate; 32, third N-type trench; 33, fourth N-type trench; 34, second oxide layer; 35, second gate metal layer; 36, second drain extension layer; 37, second source metal layer; 38, second insulating layer; 40, molding compound; 50, first source region; 51, first drain region; 52, second source region; 53, second drain region; 60, connecting wire; 70, power module; 80, automotive starter motor and control unit. Detailed Implementation

[0040] In the description of this application, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0041] Current car, motorcycle, and ship jump starters use lead-acid batteries, with a few using lithium batteries. However, due to cost and safety concerns, lithium batteries are not widely used. Both lead-acid and lithium batteries have short lifespans. Lead-acid batteries have a cycle life of approximately 300 cycles (one full charge and discharge cycle), while lithium batteries have a theoretical lifespan of approximately 500 cycles. In practical applications, due to factors such as cabin temperature, the lifespan is even shorter, generally requiring replacement after two years. Furthermore, since existing lead-acid and various lithium batteries are chemical batteries, chemical reactions are known to be temperature-sensitive. For example, in extremely cold regions, mobile phones placed in a backpack may automatically shut down. In vehicles and ships, this manifests as reduced performance and inability to start. Emergency jump starters were developed to address these emergencies. Emergency jump starters typically use large relays or MOSFETs as their switching transistors. In practical applications, whether NMOS or PMOS, two parasitic diodes exist during manufacturing. The NMOS substrate is P-type, and the drain and source terminals are N-type, naturally forming two diodes between the substrate and the drain / source terminals.

[0042] In actual MOS manufacturing, to maintain a voltage difference between the substrate and gate, the substrate and source are connected. Therefore, the diode between the substrate and source is short-circuited and negligible. The main consideration is the diode between the substrate and drain. Under normal use, since the drain voltage is always higher than the source voltage, the presence of the diode does not affect operation; current always flows from the drain (D) to the source (S), and the current is entirely controlled by the gate (G). However, car starting presents a special situation. Because cars have alternators, once the car starts successfully, the alternator generates electricity to charge the battery. At this time, the source is essentially connected to the alternator, and its potential is higher than the drain, meaning the alternator is charging the emergency starter battery. If the MOS transistor is not turned off, current can flow from the source (S) to the drain (D) without damaging the MOS transistor. However, the MOS transistor must be turned off after startup; otherwise, it will continuously discharge externally, potentially causing a short circuit. This creates a contradiction: keeping the MOS transistor on can easily lead to a short circuit, while turning it off can damage it. Therefore, in related technologies, two MOS switches are connected back-to-back in series, with the drains of two identical MOSFETs connected together and their gates connected together. This results in a large size and high cost. Furthermore, since each MOS is individually packaged and connected to pins, it increases impedance and affects the normal starting of the car. Therefore, this application provides a MOS structure, manufacturing method, and car starting system for car starting, which has the characteristics of saving space and reducing packaging costs.

[0043] The following is in conjunction with the appendix Figure 1 -Appendix Figure 7 This application will be described in further detail.

[0044] This application discloses a MOS structure for automobile starting.

[0045] Example 1

[0046] Reference Figure 1 and Figure 2The MOS structure for automotive starting includes a base island 10, a first MOS transistor 20, a second MOS transistor 30, and a molding compound 40. The first MOS transistor 20 and the second MOS transistor 30 are fixed on the base island 10, and the base island 10, the first MOS transistor 20, and the second MOS transistor 30 are all sealed within the molding compound 40. The gate of the first MOS transistor 20 is connected to the gate of the second MOS transistor 30, and the drain of the first MOS transistor 20 is connected to the drain of the second MOS transistor 30. By directly applying the two MOS transistors together in an automotive starting system, compared to the related technology of separately packaging a single MOS transistor and then soldering the two MOS transistors back-to-back, this application saves space and reduces costs. Accordingly, this application is not limited to the connection of the drain of the first MOS transistor 20 to the drain of the second MOS transistor 30; it can also be that the source of the first MOS transistor 20 is connected to the source of the second MOS transistor 30. Furthermore, in this embodiment, the MOS transistors are not limited to two N-channel MOS transistors; in variations, those skilled in the art can adjust it to two P-channel MOS transistors.

[0047] The MOS structure used for automotive starting also includes a first lead, a second lead, and a control pin. The source of the first MOS transistor 20 is connected to the first lead, the source of the second MOS transistor 30 is connected to the second lead, and the gate of the first MOS transistor 20 is connected to the control pin. Specifically, the first and second leads are used to connect to an external power supply, and the control pin is used to receive control signals to control the operating state of the MOS. In related technologies, each MOS is individually packaged and connected to leads, leading to an increase in impedance. This application packages two MOS transistors and connects three leads, thereby reducing internal resistance. Automotive starting requires a large current, for example, several hundred to one thousand amps at 12V. According to I=V / R, when V=12V, to achieve an I of one thousand amps, R must be in the milliohm range; a slightly larger impedance will prevent the car from starting.

[0048] In this embodiment, the first MOSFET 20 and the second MOSFET 30 are of the same type. The gate of the first MOSFET 20 is connected to the gate of the second MOSFET 30 via a connecting line 60, and the drain of the first MOSFET 20 is connected to the drain of the second MOSFET 30 via a connecting line 60, thus realizing the packaging of two separate MOSFETs together. It should be noted that the connecting line 60 is required to have low impedance, generally a connecting line of a few milliohms is selected.

[0049] The implementation principle of Example 1 is as follows: two separate MOS transistors are packaged together, with their gates connected, their drains connected, or their sources connected. This allows the packaged MOS transistors to be directly used in automotive starting systems without the need to solder the two separately packaged MOS transistors back to back, saving space and packaging costs.

[0050] Example 2

[0051] Reference Figure 3 and Figure 4 The difference between this embodiment and Embodiment 1 is that the first MOS transistor 20 and the second MOS transistor 30 are integrally formed. Specifically, the first MOS transistor 20 includes a first P-type substrate 21, a first N-type trench 22, a second N-type trench 23, a first oxide layer 24, a first gate metal layer 25, a first drain extension layer 26, a first source metal layer 27, and a first insulating layer 28. One side of the first P-type substrate 21 is fixed on the base island 10, and the first N-type trench 22 is formed on the first P-type substrate 21 away from the base island. A first source region 50 is formed on one side of the base island 10. A second N-type trench 23 is formed on the side of the first P-type substrate 21 away from the base island 10 to form a first drain region 51. A first oxide layer 24 covers the side of the first P-type substrate 21 away from the base island 10. A first source metal layer 27 is connected to the first source region 50. A first drain extension layer 26 is connected to the first drain region 51. A first insulating layer 28 is disposed between the first source metal layer 27 and the first drain extension layer 26. A first gate metal layer 25 is disposed on the first insulating layer 28.

[0052] The second MOS transistor 30 includes a second P-type substrate 31, a third N-type trench 32, a fourth N-type trench 33, a second oxide layer 34, a second gate metal layer 35, a second drain extension layer 36, a second source metal layer 37, and a second insulating layer 38. One side of the second P-type substrate 31 is fixed on the base island 10. The third N-type trench 32 is formed on the side of the second P-type substrate 31 away from the base island 10 to form a second source region 52. The fourth N-type trench 33 is formed on the side of the second P-type substrate 31 away from the base island 10 to form a second drain region 53. The second oxide layer 34 covers the side of the second P-type substrate 31 away from the base island 10. The second source metal layer 37 is connected to the second source region 52. The second drain extension layer 36 is connected to the second drain region 53. The second insulating layer 38 is disposed between the second source metal layer 37 and the second drain extension layer 36. The second gate metal layer 35 is disposed on the second insulating layer 38. The first drain extension layer 26 is integrally formed with the second drain extension layer 36.

[0053] Accordingly, refer to Figure 5 and Figure 6In some embodiments, the first gate metal layer 25 and the second gate metal layer 35 are also integrally formed. This eliminates the need to connect the two MOSFETs on the base island 10, enabling the packaging of two MOSFETs and allowing the packaged MOSFETs to be directly applied to automotive starting systems.

[0054] In this embodiment, both the first insulating layer 28 and the second insulating layer 38 are made of silicon dioxide or borosilicate glass.

[0055] Accordingly, in some embodiments, the first P-type substrate 21 and the second P-type substrate 31 are integrally formed, and the first gate metal layer 25 and the second gate metal layer 35, the first drain extension layer 26 and the second drain extension layer 36 are all connected by the connection line 60.

[0056] In some embodiments, the first P-type substrate 21 and the second P-type substrate 31, the first gate metal layer 25 and the second gate metal layer 35 are integrally formed, and the first drain extension layer 26 and the second drain extension layer 36 are connected by a connection line 60.

[0057] It should be noted that when the first MOSFET 20 and the second MOSFET are integrally formed, during packaging, it is only necessary to connect the first source metal layer 27 to the first lead through the connecting line 60, connect the second source metal layer 37 to the second lead through the connecting line 60, and connect the integrally formed gate metal layer to the control pin through the connecting line 60.

[0058] The implementation principle of Example 2 is as follows: When processing the wafer, the first MOS transistor 20 and the second MOS transistor 30 are processed into a single unit before packaging, so that the first gate metal layer 25 and the second gate metal layer 35, and the first drain extension layer 26 and the second drain extension layer 36 do not need to be connected by the connecting wire 60, simplifying the operation steps, realizing the packaging of two MOS transistors, and enabling the packaged MOS transistors to be directly applied to automobile starting.

[0059] This application also discloses a method for manufacturing a MOS for automobile starting.

[0060] The method for fabricating a MOS for automotive starting includes: First, etching a first N-type trench 22, a second N-type trench 23, a third N-type trench 32, and a fourth N-type trench 33 sequentially on the surface of a P-type substrate, and sequentially forming a first source region 50, a first drain region 51, a second source region 52, and a second drain region 53 through the trenches; depositing an oxide layer on the surface of the P-type substrate, and patterning and etching the first source region 50, the first drain region 51, the second source region 52, and the second drain region 53 on the oxide layer, and depositing metal to form a first source metal layer 27, a first drain extension layer 26, a second source metal layer 37, and a second drain extension layer 36, wherein the first drain extension layer 26 and the second drain extension layer 36 are integrally formed.

[0061] A first gate metal layer 25 is formed by depositing metal on the oxide layer between the first source metal layer 27 and the first drain extension layer 26, and a second gate metal layer 35 is formed by depositing metal on the oxide layer between the second source metal layer 37 and the second drain extension layer 36. The first gate metal layer 25 and the second gate metal layer 35 are integrally formed, so that the drain of the first MOSFET 20 and the drain of the second MOSFET 30, and the first gate metal layer 25 and the second gate metal layer 35 are connected during the forming process. In subsequent packaging, it is not necessary to connect the two separate MOSFETs through the connecting line 60, which reduces the internal resistance and saves space.

[0062] An insulating dielectric is deposited between the first gate metal layer 25 and the oxide layer to form a first insulating layer 28, and an insulating dielectric is deposited between the second gate metal layer 35 and the oxide layer to form a second insulating layer 38; by setting the first insulating layer 28 and the second insulating layer 38, the gate and source, and the gate and drain of the MOS transistor are isolated.

[0063] The implementation principle of the MOS fabrication method for automobile starting in this application embodiment is as follows: During the MOS forming process, when the first source region 50, the first drain region 51, the second source region 52 and the second drain region 53 are patterned and metal is deposited on the oxide layer, the first drain extension plate and the second drain extension plate are formed together, and the first gate metal layer 25 and the second gate metal layer 35 are formed together. That is, the drain of the first MOS transistor 20 and the drain of the second MOS transistor 30, and the first gate metal layer 25 and the second gate metal layer 35 are connected during the forming process, which reduces the internal resistance and saves space.

[0064] This application also discloses a car starting system.

[0065] Reference Figure 7 The system includes a MOS structure for vehicle starting as described in the above embodiment, a power module 70, and a vehicle starter motor and control unit 80. The power module 70 includes a vehicle battery and an emergency starter battery. The vehicle battery supplies power to the vehicle starter motor and control unit 80. The positive terminal of the power module 70 is electrically connected to the source of the first MOS transistor 20, and the negative terminal of the power module 70 is electrically connected to the source of the second MOS transistor 30. The vehicle starter motor and control unit 80 is connected to the power module 70, and the control terminal of the vehicle starter motor and control unit 80 is connected to the gate of the first MOS transistor 20. The vehicle starter motor and control unit 80 is used to control the conduction state of the MOS structure.

[0066] A load is connected between the power module 70 and the MOS structure. By connecting the drains and gates of two identical MOS transistors together, the MOS transistors can be effectively protected. The protection principle is as follows: Before startup, the emergency starter power supply voltage is high. If the control signal is high, both MOS transistors are turned on. Since the impedance from D to S and from S to D is the same when the MOS transistor is turned on, they can be interchanged. Current flows from S to D of the upper transistor and then from D to S of the lower transistor, energizing the load and starting the car. After the car starts, the load begins to generate electricity. If the control signal is still high, the power generated by the load normally charges the emergency starter power supply. If the control signal is low, both MOS transistors are turned off, and the current can only flow through the parasitic diode. Since the upper transistor is reverse-connected, the current cannot flow through it, thus effectively protecting the MOS transistor. Because this application packages two MOS transistors together, the gates and drains of the two MOS transistors are connected during packaging or MOS fabrication, or the two sources are connected. This allows them to be used directly to start a car without the need to solder two separate MOS transistors back to back, saving space and packaging costs, and reducing internal resistance.

[0067] The implementation principle of the car starting system in this application embodiment is as follows: the conduction state of the MOS structure is controlled by the car starter motor and control unit 80 to ensure successful car starting and save the space occupied by the MOS structure.

[0068] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A MOS structure for automotive starting, characterized in that: It includes a base island (10), a first MOS transistor (20) and a second MOS transistor (30) disposed on the base island (10), and a molding compound (40) sealing the base island (10), the first MOS transistor (20) and the second MOS transistor (30). The gate of the first MOS transistor (20) is connected to the gate of the second MOS transistor (30), and the drain of the first MOS transistor (20) is connected to the drain of the second MOS transistor (30). The first MOSFET (20) and the second MOSFET (30) are integrally formed. The first MOSFET (20) includes a first P-type substrate (21), a first N-type trench (22), a second N-type trench (23), a first oxide layer (24), a first gate metal layer (25), a first drain extension layer (26), a first source metal layer (27), and a first insulating layer (28). One side of the first P-type substrate (21) is fixed to the base island (10). The first N-type trench (22) is formed on the side of the first P-type substrate (21) away from the base island (10) to form a first source region (50). The second MOSFET (30) An N-type trench (23) is formed on the side of the first P-type substrate (21) away from the base island (10) to form a first drain region (51). The first oxide layer (24) covers the side of the first P-type substrate (21) away from the base island (10). The first source metal layer (27) is connected to the first source region (50). The first drain extension layer (26) is connected to the first drain region (51). The first insulating layer (28) is disposed between the first source metal layer (27) and the first drain extension layer (26). The first gate metal layer (25) is disposed on the first insulating layer (28). The second MOS transistor (30) includes a second P-type substrate (31), a third N-type trench (32), a fourth N-type trench (33), a second oxide layer (34), a second gate metal layer (35), a second drain extension layer (36), a second source metal layer (37), and a second insulating layer (38). One side of the second P-type substrate (31) is fixed to the base island (10). The third N-type trench (32) is formed on the side of the second P-type substrate (31) away from the base island (10) to form a second source region (52). The fourth N-type trench (33) is formed on the side of the second P-type substrate (31) away from the base island (10). The second P-type substrate (31) is located away from the base island (10) to form a second drain region (53). The second oxide layer (34) covers the side of the second P-type substrate (31) away from the base island (10). The second source metal layer (37) is connected to the second source region (52). The second drain extension layer (36) is connected to the second drain region (53). The second insulating layer (38) is disposed between the second source metal layer (37) and the second drain extension layer (36). The second gate metal layer (35) is disposed on the second insulating layer (38). The first drain extension layer (26) and the second drain extension layer (36) are integrally formed.

2. The MOS structure for automobile starting according to claim 1, characterized in that: The gate of the first MOS transistor (20) is connected to the gate of the second MOS transistor (30), and the drain of the first MOS transistor (20) is connected to the drain of the second MOS transistor (30) through a connecting line (60).

3. The MOS structure for automotive starting according to claim 1, characterized in that: The first gate metal layer (25) and the second gate metal layer (35) are integrally formed.

4. The MOS structure for automobile starting according to claim 1, characterized in that: The first insulating layer (28) and the second insulating layer (38) are both made of silicon dioxide or borosilicate glass.

5. The MOS structure for automobile starting according to claim 1, characterized in that: It also includes a first lead, a second lead, and a control pin. The source of the first MOS transistor (20) is connected to the first lead, the source of the second MOS transistor (30) is connected to the second lead, and the gate of the first MOS transistor (20) is connected to the control pin.

6. A method for manufacturing a MOS for automobile starting, characterized in that: This includes sequentially forming a first source region (50), a first drain region (51), a second source region (52), and a second drain region (53) on a P-type substrate; An oxide layer is deposited on the surface of a P-type substrate. The first source region (50), the first drain region (51), the second source region (52) and the second drain region (53) are patterned on the oxide layer and metal is deposited to form a first source metal layer (27), a first drain extension layer (26), a second source metal layer (37) and a second drain extension layer (36), wherein the first drain extension layer (26) and the second drain extension layer (36) are integrally formed. A first gate metal layer (25) is formed by depositing metal on the oxide layer between the first source metal layer (27) and the first drain extension layer (26), and a second gate metal layer (35) is formed by depositing metal on the oxide layer between the second source metal layer (37) and the second drain extension layer (36), wherein the first gate metal layer (25) and the second gate metal layer (35) are integrally formed.

7. The method for manufacturing a MOS for automobile starting according to claim 6, characterized in that: The method further includes: depositing an insulating medium between the first gate metal layer (25) and the oxide layer to form a first insulating layer (28); and depositing an insulating medium between the second gate metal layer (35) and the oxide layer to form a second insulating layer (38).

8. An automobile starting system, comprising a MOS structure for automobile starting as described in any one of claims 1-5, a power module (70), and an automobile starter motor and control unit (80), wherein the positive terminal of the power module (70) is electrically connected to the source of the first MOS transistor (20), the negative terminal of the power module (70) is electrically connected to the source of the second MOS transistor (30), the automobile starter motor and control unit (80) is connected to the power module (70), the control terminal of the automobile starter motor and control unit (80) is connected to the gate of the first MOS transistor (20), and the automobile starter motor and control unit (80) is used to control the conduction state of the MOS structure.

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