HBT (Heterojunction Bipolar Transistor), radio frequency power amplifier and preparation method of HBT

Abstract

The invention provides an HBT (Heterojunction Bipolar Transistor), a radio frequency power amplifier and a preparation method of the HBT, the HBT comprises a substrate and a plurality of tube cores, and the plurality of tube cores are connected in parallel on the substrate; each tube core comprises a collector electrode main body, a base electrode main body and an emitter electrode main body which are sequentially overlapped, the collector electrode main body is provided with a collector electrode pin, the base electrode main body is provided with a base electrode pin, and the emitter electrode main body is provided with an emitter electrode pin; the HBT transistor further comprises an isolation structure, the isolation structure is respectively connected with the emitting electrode pins of the tube cores, and the isolation structure is grounded between two adjacent tube cores. According to the HBT transistor, the radio frequency power amplifier and the preparation method of the HBT transistor, the heat dissipation capability of the transistor can be improved, the risk of thermal failure of the tube core is reduced, and the efficiency of the radio frequency power amplifier is improved.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor devices, and in particular, to an HBT transistor, a radio frequency power amplifier, and a method for manufacturing an HBT transistor. Background Art

[0002] A radio frequency power amplifier is an important electronic device, which is widely used in fields such as communication devices, radar systems, and electronic test equipment. The main function of a radio frequency power amplifier is to achieve the power amplification function of radio frequency signals. Its efficiency is generally 50%, because half of the energy is consumed in the form of heat dissipation. Heat dissipation will cause the core temperature (die temperature) of the radio frequency power amplifier to be too high. Calculated by the MTTF formula, for every 10°C increase in the die temperature, its lifetime is shortened by half. Therefore, the heat dissipation design of the radio frequency power amplifier is an important part to ensure its performance and stability.

[0003] The substrate of the HBT process is mostly GaAs (gallium arsenide), and its thermal conductivity is very poor. In the design of a radio frequency power amplifier, due to the large power required, it is necessary to achieve the required high power through the form of parallel connection of several dies. As Figure 1 shown in the top view of a conventional HBT transistor, the independent die therein is also the main heat source of the transistor. In the transistor of this structure, there are two heat dissipation paths for each die. The first is longitudinal transmission, that is, transmission in the direction of the substrate (the heat of the die is transferred to the upper surface of the substrate, the metal on the upper surface is connected to the metal in the ground hole, and the heat is dissipated outward through the metal in the ground hole). This mode is a good heat transfer mode; the second is lateral transmission, that is, heat is transferred between different dies. For example, heat is transferred between two adjacent dies. This mode will make the temperature of the die in the middle part higher than that of the die closer to the edge, and the temperatures of the dies are inconsistent, increasing the risk of thermal failure of the die in the middle position. Summary of the Invention

[0004] Based on this, the present application provides an HBT transistor, a radio frequency power amplifier, and a method for manufacturing an HBT transistor to improve the problems of low efficiency of the radio frequency power amplifier caused by the difficult heat dissipation of the HBT transistor die in the prior art and the thermal failure of the die caused by lateral heat transfer.

[0005] To achieve the above object, the technical solution of the embodiment of the present application is realized as follows:

[0006] In a first aspect, an embodiment of the present application provides an HBT transistor, including a substrate and a plurality of die. The plurality of die are connected in parallel on the substrate; each die respectively includes a collector body, a base body, and an emitter body stacked in sequence. A collector pin is provided on the collector body, a base pin is provided on the base body, and an emitter pin is provided on the emitter body;

[0007] The HBT transistor further includes an isolation structure. The isolation structure is respectively connected to the emitter pins of the die, and the isolation structure is grounded between two adjacent die.

[0008] In one embodiment, the isolation structure includes a first connection metal, a connecting member, and a heat dissipation metal; the first connection metal is provided on the emitter pin and interconnects the emitter pins; the heat dissipation metal is provided on the substrate and is located on a side of the first connection metal close to the substrate. The heat dissipation metal is connected to a grounding hole of the substrate; the connecting member is provided between two adjacent emitter pins. One end of the connecting member is connected to the first connection metal, and the other end is connected to the heat dissipation metal.

[0009] In one embodiment, the plurality of die are divided into at least two die groups. The die in each die group are arranged in a row and spaced apart, and every two adjacent die groups are arranged in a mirror image of each other.

[0010] In one embodiment, each die group is respectively provided with a first connection metal. The first connection metal is respectively connected to the emitter pins of the die in each die group, and a connecting member is respectively provided between every two adjacent emitter pins.

[0011] In one embodiment, the HBT transistor includes a total of five metal layers, which are, in sequence from the side close to the substrate to the side far from the substrate, a first metal layer, a second metal layer, a third metal layer, a fourth metal layer, and a fifth metal layer. The first metal layer forms the collector pin, the second metal layer forms the base pin, the third metal layer forms the emitter pin, the fourth metal layer forms the heat dissipation metal, and the fifth metal layer forms the first connection metal.

[0012] In one embodiment, at least one second connection metal is provided between every two adjacent and correspondingly arranged die groups. The second connection metal is formed by the fourth metal layer. The second connection metal is connected to the grounding hole, and the second connection metals are connected in parallel and led out to form the emitter of the HBT transistor.

[0013] In one embodiment, each of the connecting members is respectively connected to one of the heat dissipation metals, and all of the heat dissipation metals in each two adjacent and correspondingly arranged die sets are respectively connected to the corresponding second connecting metal.

[0014] In one embodiment, each die set is respectively provided with a third connecting metal, the third connecting metals are respectively connected to the base pins in the same die set, and the third connecting metals are connected in parallel and led out to form the base of the HBT transistor.

[0015] In a second aspect, an embodiment of the present application provides a radio frequency power amplifier, including the HBT transistor as described above.

[0016] In a third aspect, an embodiment of the present application provides a method for manufacturing an HBT transistor, including the following steps:

[0017] S1. Provide a semiconductor substrate, generate an epitaxial layer on the substrate, and respectively and sequentially form a collector body, a base body, and an emitter body on the epitaxial layer through photolithography and ion implantation processes;

[0018] S2. Form a first metal layer on the surface of the epitaxial layer, pattern the first metal layer, and form a collector pin on the collector body;

[0019] S3. Isolate and form a second metal layer on the surface of the first metal layer, pattern the second metal layer, and form the base pin;

[0020] S4. Isolate and form a third metal layer on the surface of the second metal layer, pattern the third metal layer, and form an emitter pin;

[0021] S5. Isolate and form a fourth metal layer on the surface of the third metal layer, pattern the fourth metal layer, and part of the fourth metal layer forms a heat dissipation metal, part forms a first wiring metal, and part forms a second connecting metal;

[0022] The heat dissipation metals are respectively connected to the second connecting metal and the emitter pin, and the second connecting metal is connected to the ground hole of the substrate;

[0023] The first wiring metal and the heat dissipation metal are not electrically connected to each other;

[0024] S6. Drill connection holes between two adjacent emitter pins, and arrange connecting members in the connection holes. One end of the connecting member close to the substrate is connected to the heat dissipation metal;

[0025] S7. Isolate and form a fifth metal layer on the surface of the fourth metal layer, pattern the fifth metal layer, with part of the fifth metal layer forming a first connection metal and part forming a second wiring metal;

[0026] The first connection metal is connected to the end of the connecting member away from the substrate, and the first connection metal is connected to the emitter pin and is not electrically connected to the second wiring metal.

[0027] This application has at least the following beneficial effects: Based on the original die structure, the HBT transistor provided in this application connects an isolation structure to the emitter pin of the die, and the isolation structure is grounded between two adjacent dies, enabling the heat dissipated by the die to be directly conducted to the ground through the isolation structure, allowing the heat of the die to be quickly dissipated to the outside. The setting of the isolation structure reduces the probability of lateral heat transfer between dies, plays a heat insulation role between dies, improves the heat dissipation ability of the transistor, reduces the risk of thermal failure of the die, is beneficial to improving the efficiency of the RF power amplifier, extends the service life of the RF power amplifier, and enhances the stability of the RF power amplifier. The manufacturing method of the HBT transistor provided in this application is simple, can adopt the traditional process manufacturing flow, without adding complex manufacturing processes. Only based on the third and fourth metal layers of the original transistor structure, retaining a part of the structure as the heat dissipation structure can neither reduce the production efficiency nor increase the production cost. Description of the Drawings

[0028] Figure 1 Is a top view structural schematic diagram of a conventional HBT transistor.

[0029] Figure 2 Is a top view structural schematic diagram of the HBT transistor according to an embodiment of this application.

[0030] Figure 3 Is an internal structural schematic diagram of the HBT transistor according to an embodiment of this application ( Figure 2 Cross-sectional view taken along the A-A direction, without hatched shading).

[0031] Figure 4 Is a top view structural schematic diagram of the HBT transistor according to another embodiment of this application.

[0032] Figure 5 Is Figure 2 A color schematic diagram of the top view structure of the HBT transistor of the shown embodiment.

[0033] Figure 6 Is a thermal simulation comparison diagram between the HBT transistor with the traditional process structure and the HBT transistor with the structure of the embodiment of this application.

[0034] The meanings of the reference numerals in the drawings are as follows:

[0035] 1. Die; 11. Collector pin; 12. Base pin; 13. Emitter pin; 14. Collector body; 15. Base body; 16. Emitter body; 2. First connecting metal; 3. Second connecting metal; 4. Third connecting metal; 5. Fourth connecting metal; 6. Heat dissipation metal; 7. Connecting member; 8. Grounding hole; 9. Substrate. Specific embodiments

[0036] The technical solution of the present application will be further described in detail below in conjunction with the drawings in the specification and specific embodiments.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used herein in the description of this application are only for the purpose of describing specific embodiments and are not intended to limit the implementation of this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0038] In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "center", "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, and is only for the convenience of describing this 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 this application. In the description of this application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0039] In the description of this application, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0040] Please refer to Figure 2 , the HBT transistor of the embodiment of this application includes a substrate 9 and a plurality of dies 1, and the plurality of dies 1 are connected in parallel on the substrate 9. Each die 1 respectively includes a collector body 14, a base body 15 and an emitter body 16 which are stacked in sequence. A collector pin 11 is provided on the collector body 14, a base pin 12 is provided on the base body 15, and an emitter pin 13 is provided on the emitter body 16.

[0041] The HBT transistor of this embodiment further includes an isolation structure. The isolation structure is respectively connected to the emitter pin 13 of the die 1, and the isolation structure is grounded between two adjacent dies 1.

[0042] The collector body 14, the base body 15, and the emitter body 16 are stacked on the substrate 9 in sequence from bottom to top. Each die 1 respectively includes an emitter pin 13 provided on the emitter body 16, one or two base pins 12 provided on the base body 15, and one or two collector pins 11 provided on the collector body 14. The collector body 14, the base body 15, and the emitter body 16 are doped semiconductor materials, such as GaAs (gallium arsenide); the collector pins 11, the base pins 12, and the emitter pins 13 are conductive metals, such as copper. The substrate 9 is made of semiconductor material, such as GaAs.

[0043] As Figure 2 and Figure 3 shown, the isolation structure of this embodiment includes a first connection metal 2, a connecting member 7, and a heat dissipation metal 6. The first connection metal 2 is provided on the emitter pin 13 and interconnects the emitter pins 13; the heat dissipation metal 6 is provided on the substrate 9 and is located on the side of the first connection metal 2 close to the substrate 9. The heat dissipation metal 6 is connected to the grounding hole 8; the connecting member 7 is provided between two adjacent emitter pins 13. One end of the connecting member 7 is connected to the first connection metal 2, and the other end is connected to the heat dissipation metal 6. A connecting member 7 can be respectively provided between every two adjacent dies 1, or only between some adjacent dies 1, which can be specifically set according to actual heat dissipation requirements. The heat dissipation effect of the structure with a connecting member 7 respectively provided between every two adjacent dies 1 is the best.

[0044] The collector body 14, the base body 15, and the emitter body 16 of the die 1 are the main heat sources of the die 1, and the collector pins 11 of each die 1 are the main components for dissipating heat. By providing the heat dissipation metal 6, the emitter pins 13 of the die 1 can be grounded. By providing the connecting member 7 between the emitter pins 13, the heat transfer between adjacent dies 1 can be reduced, so that the heat dissipated by the die 1 can be quickly transferred outward through the metal in the grounding hole 8, avoiding lateral heat propagation, thereby reducing the risk of thermal failure of the die 1.

[0045] Traditional processes often reduce heat transfer between die 1 by increasing the spacing between adjacent die 1. However, this method results in a larger volume of the transistor at the same power. At the same time, the parasitic parameters also increase due to the increased distance between die 1, leading to a decline in the high-frequency performance of the chip and restricting the application of radio frequency power amplifiers in the high-frequency range. In the HBT transistor of the embodiment of the present application, a connecting member 7 is provided between two emitter pins 13, enabling the heat of die 1 to quickly dissipate outward through the grounding holes 8 without spreading to adjacent die 1, avoiding lateral heat transfer and reducing the risk of thermal failure of die 1. Moreover, this structure does not additionally occupy the space of the product, does not cause an increase in the final volume of the product, and the process formation method is very simple.

[0046] Specifically, in this embodiment, an HBT transistor includes at least two die groups. A die group refers to a plurality of die 1 that are spaced apart and arranged in a row. For example, as Figure 2 shown, this HBT transistor includes two die groups, and each die group includes 5 die 1 respectively. Of course, an HBT transistor can also include more die groups. For example, as Figure 4 shown, this HBT transistor includes 4 die groups, and its 4 die groups are arranged in pairs. When the HBT transistor includes multiple die groups, several die 1 can be arranged in an array. Preferably, every two adjacent die groups are set as mirror images of each other. The advantage of the mirror image setting is to facilitate the extraction of heat and the extraction of circuits later, while reducing the complexity of the circuits. When two die groups are set as mirror images of each other, the second connection metal 3 and the third connection metal 4 can be shared at the gap between them, thereby reducing the complexity of the circuits and the production difficulty.

[0047] As Figure 2 and Figure 3 shown, each die group can be respectively provided with a first connection metal 2. The first connection metal 2 is respectively connected to the emitter pins 13 of the die 1 in each die group and is connected to the heat dissipation metal 6. That is, a strip-shaped metal layer can be covered on the emitter pins 13 of the same die group, and this metal layer is the first connection metal 2. The first connection metal 2 (as shown by the blue long strip part in Figure 5 shown) extends along the arrangement direction of die 1, is respectively connected to each emitter pin 13, and is also connected to the heat dissipation metal 6 (as shown in Figure 5The green bar part shown) is connected, so that the heat dissipated from the emitter pin 13 can be directly introduced into the metal of the ground via hole 8 through the first connecting metal 2 and the heat dissipation metal 6, and then dissipated to the outside. At the same time, the setting of the first connecting metal 2 also increases the heat dissipation area of the emitter pin 13, so that the heat of the emitter pin 13 can also be directly transmitted to the air through the first connecting metal 2, adding a heat dissipation path for the emitter pin 13 and improving the heat dissipation capacity. To further increase the heat dissipation performance of the HBT transistor, a heat dissipation structure (not shown) can also be provided at the ground via hole 8 of the substrate 9, such as adding a heat conducting metal, such as a copper block, etc., so that the heat dissipation structure is connected to the metal of the ground via hole 8, thereby further enhancing the heat dissipation capacity. The heat dissipation structure is provided on the side of the ground via hole 8 of the substrate 9 away from the emitter pin 13.

[0048] As Figure 2 , Figure 3 and Figure 5 shown, in some embodiments, in each die group, connection holes are respectively provided between every two adjacent dies 1, and communication members 7 (as Figure 5 shown in the red part) are respectively provided in the connection holes. One end of the communication member 7 is connected to the first connecting metal 2, and the other end is connected to the heat dissipation metal 6. In the same die group, a via hole can be opened at the gap between two adjacent dies 1, and the communication member 7 is provided in the via hole. The communication member 7 can be, for example, a copper column. The top of the copper column (referring to the direction in the figure, that is, the end away from the substrate 9) is correspondingly arranged with the first connecting metal 2 and forms a connection with the first connecting metal 2. The bottom of the copper column (referring to the direction in the figure, that is, the end close to the substrate 9) is correspondingly arranged with the heat dissipation metal 6 and forms a connection with the heat dissipation metal 6. In this way, the emitter pins 13 of all the dies 1 in a die group are respectively connected to the metal in the ground via hole 8 of the substrate 9 through the first connecting metal 2, the communication member 7 and the heat dissipation metal 6, so that the heat dissipated from the emitter pins 13 of the die 1 can be directly conducted to the outside through the ground via hole 8, improving the heat dissipation capacity of the transistor. At the same time, the connection method of arranging the communication member 7 in the connection hole blocks the heat transfer between the dies 1, forming a thermal isolation between the dies 1, which can improve the temperature balance of the dies 1, avoid the problem of thermal failure of the die 1 in the middle position due to excessive temperature, improve the stability of the transistor, and extend the service life of the transistor.

[0049] The HBT transistor of this embodiment includes a total of five metal layers. From the side close to the substrate 9 to the side far from the substrate 9, they are the first metal layer, the second metal layer, the third metal layer, the fourth metal layer, and the fifth metal layer in sequence. The first metal layer forms the collector pin 11, the second metal layer forms the base pin 12, the third metal layer forms the emitter pin 13, the fourth metal layer forms the heat dissipation metal 6, and the fifth metal layer forms the first connection metal 2. The first metal layer, the second metal layer, and the third metal layer are the three electrode layers of a conventional HBT transistor, and the fourth metal layer and the fifth metal layer are the circuit layers of a conventional HBT transistor. In this embodiment, the heat dissipation metal 6 is formed on the fourth metal layer and the first connection metal 2 is formed on the fifth metal layer. This forming method will not affect the previous electrode production process after the formation of the electrode layer, ensuring the reliability of the product structure. At the same time, using the metal of the circuit layer to form the heat dissipation metal 6 and the first connection metal 2 will not increase the production difficulty of the circuit layer. Only the shape of the mask needs to be modified. At the same time, according to the comprehensive consideration of heat dissipation and other performance requirements, process parameters such as the metal thickness of the circuit layer can be adjusted to make the product present better performance indicators. In some embodiments, the first metal layer can also be used to form the heat dissipation metal 6, which can also achieve the heat dissipation function.

[0050] There is at least one second connection metal 3 between every two adjacent and correspondingly arranged die sets. The second connection metal 3 is formed by the fourth metal layer. The second connection metal 3 is connected to the metal in the grounding hole 8, and the second connection metal 3 is connected in parallel and led out to form the emitter of the HBT transistor. For example, in Figure 2 the shown embodiment, there are a total of 3 second connection metals 3 arranged longitudinally (the arrangement direction of the dies 1 in each die set) at the gap between two correspondingly arranged die sets. The heat dissipation metals 6 on both sides of the second connection metal 3 can be respectively connected to the second connection metal 3. Two die sets can share a set of second connection metals 3 to reduce the complexity of the structure, and a more reasonable layout can improve the space utilization rate of the product. This is also the reason for mirroring two adjacent die sets. One grounding hole 8 is respectively connected to the side of each second connection metal 3 close to the substrate 9, and the second connection metal 3 is directly connected to the metal in the grounding hole 8 to facilitate heat dissipation. In this embodiment, a heat dissipation metal 6 is respectively connected to each connecting member 7. In other embodiments, it can also be specifically set according to the specific circuit layout. For example, like the first connection metal 2, the heat dissipation metals 6 corresponding to the same die set can be set as a whole, and then the first connection metal 2 and the heat dissipation metal 6 are connected through the connecting member 7. The connecting member 7 does not have to be provided between every two adjacent dies 1. It can be reasonably set according to the actual heat distribution. For example, it can be set at intervals or only between the dies 1 close to the middle position. It is the best implementation method to set 1 connecting member 7 between every two adjacent dies 1.

[0051] As Figure 2 shown, each die group is respectively provided with at least one third connection metal 4. The base pins 12 of all the dies 1 arranged on the same side in each die group are respectively connected to the same third connection metal 4. All the third connection metals 4 are connected in parallel and led out to form the base of the HBT transistor. The third connection metal 4 in this embodiment is similar to the first connection metal 2 and is also a strip-shaped metal layer covering the base pins 12. When a column of base pins 12 is respectively arranged on both sides of the emitter pin 13 in a die group (that is, two columns of base pins 12 are included in a die group), two third connection metals 4 can be correspondingly arranged (one third connection metal 4 is arranged for each column of base pins 12). When only one column of base pins 12 is arranged in a die group, only one third connection metal 4 needs to be correspondingly arranged. At this time, the third connection metal 4 can be arranged on the side where two adjacent die groups are far away from each other to make full use of the internal space of the transistor. The third connection metal 4 can be formed by using a fourth metal layer, for example.

[0052] A fourth connection metal 5 can also be arranged between every two adjacent and correspondingly arranged die groups. The fourth connection metal 5 can be formed by using a fifth metal layer. The fourth connection metal 5 is located above the second connection metal 3 (in the illustrated direction, that is, on the side far away from the substrate 9). The collector pins 11 in the two die groups located on both sides of the fourth connection metal 5 can be connected to the fourth connection metal 5. All the fourth connection metals 5 are connected in parallel and led out to form the collector of the HBT transistor.

[0053] An embodiment of the present application also provides a radio frequency power amplifier, including the above-mentioned HBT transistor. The HBT transistor effectively improves the heat dissipation performance, prolongs the service life of the transistor, improves the stability of the transistor, and can effectively improve the efficiency of the radio frequency power amplifier.

[0054] An embodiment of the present application also provides a preparation method of an HBT transistor for preparing the above-mentioned HBT transistor, which specifically includes the following steps:

[0055] S1. Provide a semiconductor substrate 9, generate an epitaxial layer on the substrate 9, and respectively and sequentially form a collector body 14, a base body 15, and an emitter body 16 on the epitaxial layer through photolithography and ion implantation processes.

[0056] In this embodiment, the material of the semiconductor substrate 9 is GaAs, and the collector body 14, the base body 15, and the emitter body 16 are respectively doped GaAs.

[0057] S2. Form a first metal layer on the surface of the epitaxial layer, pattern the first metal layer, and form a collector pin 11 on the collector body 14.

[0058] S3. Isolate and form a second metal layer on the surface of the first metal layer, pattern the second metal layer to form the base pin 12.

[0059] S4. Isolate and form a third metal layer on the surface of the second metal layer, pattern the third metal layer to form the emitter pin 13.

[0060] S5. Isolate and form a fourth metal layer on the surface of the third metal layer, pattern the fourth metal layer. Part of the fourth metal layer forms the heat dissipation metal 6, part forms the first wiring metal, and part forms the second connection metal 3.

[0061] The heat dissipation metal 6 is respectively connected to the second connection metal 3 and the emitter pin 13, and the second connection metal 3 is connected to the ground hole 8 of the substrate 9.

[0062] The first wiring metal and the heat dissipation metal 6 are not electrically connected to each other. The first wiring metal is mainly used as the circuit layer of the transistor to form a wire and play an interconnection role.

[0063] In this embodiment, the heat dissipation metal 6 utilizes the fourth metal layer of the original transistor to realize the interconnection between the emitter pin 13 and the second connection metal 3. At the same time, the second connection metal 3 also utilizes the original fourth metal layer, and the second connection metal 3 is connected to the metal in the ground hole 8 of the substrate 9. Thus, the heat generated by the heat source can be directly led out through the first connection metal 2, the connecting member 7, the heat dissipation metal 6 and the second connection metal 3 by the ground hole 8, playing a role in rapid heat dissipation. At the same time, the adverse effect of heat transfer between the dies 1 is avoided, and the working stability of the die 1 is greatly improved.

[0064] S6. Drill a connection hole between two adjacent emitter pins 13. The depth of the connection hole is drilled until the bottom of the hole is opened to the surface of the heat dissipation metal 6. A connecting member 7 is arranged in the connection hole, and one end of the connecting member 7 close to the substrate 9 is connected to the heat dissipation metal 6.

[0065] S7. Isolate and form a fifth metal layer on the surface of the fourth metal layer, pattern the fifth metal layer. Part of the fifth metal layer forms the first connection metal 2, and part forms the second wiring metal;

[0066] The first connection metal 2 is connected to one end of the connecting member 7 far from the substrate 9, and the first connection metal 2 is respectively connected to the emitter pin 13 and is not electrically connected to the second wiring metal.

[0067] The second wiring metal is also mainly used as the circuit layer of the transistor to form a wire and play an interconnection role.

[0068] The first connection metal 2 in this embodiment utilizes the fifth metal layer in the original transistor structure to realize the interconnection of the emitter pins 13 of the die 1.

[0069] AsFigure 6 As shown, to prove the heat dissipation performance of the HBT transistor according to the embodiments of the present application, thermal simulation comparison is specifically carried out. The left side in the figure is the thermal simulation diagram of the HBT transistor with the traditional process structure, and the right side is the thermal simulation diagram of the HBT transistor according to the embodiments of the present application. The ordinate in the figure is temperature. It can be seen from the figure that the highest temperature of the traditional HBT transistor is 161°C, and the highest temperature of the HBT transistor according to the embodiments of the present application is 148°C. The highest temperature of the HBT transistor according to the embodiments of the present application has decreased by 13°C compared with the highest temperature of the traditional HBT transistor. Thus, it can be seen that the HBT transistor according to the embodiments of the present application greatly reduces the heat conduction between die 1, making the temperatures of die 1 at different positions not vary much, and greatly reducing the risk of thermal failure of die 1 at the middle position.

[0070] The HBT transistor, radio frequency power amplifier and preparation method of the HBT transistor provided by the embodiments of the present application utilize the metal layer structure of the original transistor to realize the interconnection of the emitter pins of the die, and directly export heat through the grounding holes through the connecting member, heat dissipation metal and the second connecting member, improving the heat dissipation capacity. At the same time, the first connecting metal also increases the heat dissipation area, enabling heat to directly exchange heat with air through the first connecting metal, adding a heat transfer path. The setting of the first connecting metal does not increase the difficulty of the process flow nor the manufacturing cost. By providing a connection hole and a connecting member between two dies, the first connecting metal and the heat dissipation metal are interconnected, blocking the heat transfer path between the dies, reducing the lateral transfer of heat, avoiding the risks of thermal failure and thermal breakdown of the die, and extending the service life of the die. At the same time, the above structure connects the emitter of the die to the grounding hole of the substrate through metal, enabling the voltage or current passing through the die to directly flow to the zero potential instead of flowing to the adjacent die, increasing the electrical isolation between the dies, enhancing the degree of electrical isolation between the dies, reducing the mutual interference between the dies, and further improving the radio frequency performance of the radio frequency power amplifier. The HBT transistor provided by the embodiments of the present application effectively improves the heat dissipation capacity of the transistor without changing the spacing between the original dies, reduces the generation of parasitic capacitance and inductance between the dies, and improves the high-frequency performance of the radio frequency power amplifier.

[0071] It should be noted that in this text, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device including a series of elements not only includes those elements but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including that element.

[0072] As described above, it is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims described above.

Claims

1. An HBT transistor, characterized in that, It includes a substrate (9) and a plurality of die (1), and the plurality of die (1) are connected in parallel on the substrate (9); each die (1) respectively includes a collector body (14), a base body (15) and an emitter body (16) which are stacked in sequence. A collector pin (11) is provided on the collector body (14), a base pin (12) is provided on the base body (15), and an emitter pin (13) is provided on the emitter body (16). The HBT transistor further includes an isolation structure. The isolation structure is respectively connected to the emitter pins (13) of the die (1), and the isolation structure is grounded between two adjacent die (1).

2. The HBT transistor according to claim 1, characterized in that, The isolation structure includes a first connection metal (2), a connecting member (7) and a heat dissipation metal (6); the first connection metal (2) is provided on the emitter pin (13) and interconnects the emitter pins (13); the heat dissipation metal (6) is provided on the substrate (9) and is located on the side of the first connection metal (2) close to the substrate (9). The heat dissipation metal (6) is connected to the ground hole (8) of the substrate (9); the connecting member (7) is provided between two adjacent emitter pins (13), one end of the connecting member (7) is connected to the first connection metal (2), and the other end is connected to the heat dissipation metal (6).

3. The HBT transistor according to claim 2, characterized in that, The plurality of die (1) are divided into at least two die groups. The die (1) in each die group are arranged in a row and spaced apart, and every two adjacent die groups are mirror images of each other.

4. The HBT transistor according to claim 3, characterized in that, Each die group is respectively provided with a first connection metal (2). The first connection metal (2) is respectively connected to the emitter pins (13) of the die (1) in each die group, and a connecting member (7) is respectively provided between every two adjacent emitter pins (13).

5. The HBT transistor according to claim 4, wherein The HBT transistor includes a total of five metal layers, which are, in sequence from the side close to the substrate (9) to the side far from the substrate (9), a first metal layer, a second metal layer, a third metal layer, a fourth metal layer and a fifth metal layer. The first metal layer forms the collector pin (11), the second metal layer forms the base pin (12), the third metal layer forms the emitter pin (13), the fourth metal layer forms the heat dissipation metal (6), and the fifth metal layer forms the first connection metal (2).

6. The HBT transistor according to claim 5, wherein At least one second connection metal (3) is provided between every two adjacent and correspondingly arranged die groups. The second connection metal (3) is formed by the fourth metal layer. The second connection metal (3) is connected to the ground hole (8), and the second connection metals (3) are connected in parallel and led out to form the emitter of the HBT transistor.

7. The HBT transistor according to claim 6, wherein Each connecting member (7) is respectively connected to a heat dissipation metal (6), and all the heat dissipation metals (6) in every two adjacent and correspondingly arranged die groups are respectively connected to the corresponding second connection metals (3).

8. The HBT transistor according to claim 3, characterized in that, Each of the die sets is respectively provided with a third connecting metal (4), the third connecting metal (4) is respectively connected to the base pins (12) in the same die set, and the third connecting metals (4) are connected in parallel and led out to form the base of the HBT transistor.

9. A radio frequency power amplifier, characterized in that, An HBT transistor according to any one of claims 1 to 8.

10. A method for manufacturing an HBT transistor, characterized in that, Comprising the following steps: S1. Provide a semiconductor substrate (9), generate an epitaxial layer on the substrate (9), and sequentially form a collector body (14), a base body (15), and an emitter body (16) on the epitaxial layer through photolithography and ion implantation processes; S2. Form a first metal layer on the surface of the epitaxial layer, pattern the first metal layer, and form a collector pin (11) on the collector body (14); S3. Isolate and form a second metal layer on the surface of the first metal layer, pattern the second metal layer, and form a base pin (12); S4. Isolate and form a third metal layer on the surface of the second metal layer, pattern the third metal layer, and form an emitter pin (13); S5. Isolate and form a fourth metal layer on the surface of the third metal layer, pattern the fourth metal layer, and part of the fourth metal layer forms a heat dissipation metal (6), part forms a first wiring metal, and part forms a second connecting metal (3); The heat dissipation metal (6) is respectively connected to the second connecting metal (3) and the emitter pin (13), and the second connecting metal (3) is connected to the ground hole (8) of the substrate (9); The first wiring metal and the heat dissipation metal (6) are not electrically connected to each other; S6. Drill a connection hole between two adjacent emitter pins (13), and dispose a connecting member (7) in the connection hole. One end of the connecting member (7) close to the substrate (9) is connected to the heat dissipation metal (6); S7. Isolate and form a fifth metal layer on the surface of the fourth metal layer, pattern the fifth metal layer, and part of the fifth metal layer forms a first connecting metal (2), and part forms a second wiring metal; The first connecting metal (2) is connected to one end of the connecting member (7) away from the substrate (9), and the first connecting metal (2) is connected to the emitter pin (13) and is not electrically connected to the second wiring metal.

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