A radio frequency power amplifier and electronic device

Abstract

The application discloses a radio frequency power amplifier, comprising a transistor and a plurality of layers of substrates stacked from bottom to top, through holes are distributed between adjacent two layers of the substrates, the transistor is located between any two adjacent layers of the substrates except the topmost layer of the substrates, and the substrate thickness of the transistor is less than or equal to the distance between the two adjacent layers of the substrates where the transistor is located. In the application, the transistor is located between any two adjacent layers of the substrates except the topmost layer, and the substrate thickness of the transistor is less than or equal to the distance between the two adjacent layers of the substrates, so that the electric length from the emitter to the ground on the transistor is reduced, the grounding inductance is reduced, and since the transistor is not located on the topmost layer, the heat dissipation path is shortened, the heat dissipation path thermal resistance is reduced, the heat dissipation effect is improved, and the performance of the radio frequency power amplifier is enhanced. In addition, the application also provides an electronic device with the above advantages.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor technology, in particular to a radio frequency power amplifier and an electronic device. BACKGROUND

[0002] A radio frequency power amplifier (RF PA) is a main component in a transmitting system, which amplifies and outputs an input signal. A structure diagram of an existing radio frequency power amplifier is shown in FIG. 1, which includes a multilayer substrate and a transistor 1, and there are through holes 3 between two adjacent substrates. The transistor 1 is located on the upper surface of the topmost substrate. The electrical length of the emitter 11 of the transistor 1 to the ground is the thickness of the base of the transistor 1 and the multilayer substrate, which is relatively large, resulting in a large ground inductance of the RF PA, which is sensitive to the ground. The worse the ground is, the lower the current of the RF PA is. In addition, since the transistor 1 is located on the upper surface of the topmost substrate, the heat dissipation path of the emitter 11 of the transistor 1 is from the topmost layer to the bottommost layer through the through holes 3, which has a poor heat dissipation effect and seriously affects the performance of the RF PA. Figure 1

[0003] Therefore, how to solve the above technical problems should be the focus of the skilled in the art. SUMMARY

[0004] The purpose of the present application is to provide a radio frequency power amplifier and an electronic device to reduce the ground inductance and heat dissipation path thermal resistance of the radio frequency power amplifier and improve the performance of the radio frequency power amplifier.

[0005] To solve the above technical problems, the present application provides a radio frequency power amplifier, which comprises:

[0006] a transistor and a multilayer substrate stacked in order from bottom to top, through holes are distributed between two adjacent substrates, the transistor is located between any two adjacent substrates except the topmost substrate, and the thickness of the substrate of the transistor is less than or equal to the distance between the two adjacent substrates where the transistor is located.

[0007] Optionally, in the radio frequency power amplifier, the transistor is a heterojunction bipolar transistor or a bipolar junction transistor or a field effect transistor.

[0008] Optionally, in the radio frequency power amplifier, the transistor is installed in a front-up or front-down manner, wherein the front surface of the transistor is the surface where the emitter is located.

[0009] Optionally, in the radio frequency power amplifier, the number of transistors is multiple and they are distributed in an array.

[0010] ​Optionally, in the radio frequency power amplifier, the heterojunction bipolar transistor is any one of the following transistors:

[0011] Gallium arsenide heterojunction bipolar transistor, silicon germanium heterojunction bipolar transistor, gallium nitride heterojunction bipolar transistor, pseudomorphic high electron mobility transistor.

[0012] Optionally, in the radio frequency power amplifier, the substrate is any one of the following:

[0013] Organic substrate, high-temperature co-fired ceramic substrate, low-temperature co-fired ceramic substrate.

[0014] Optionally, in the radio frequency power amplifier, the number of layers of the substrate is 4, 6 or 8.

[0015] The present application also provides an electronic device comprising any one of the radio frequency power amplifiers described above.

[0016] The radio frequency power amplifier provided by the present application comprises a transistor and a plurality of stacked substrates, and a via is arranged between any two adjacent substrates except the topmost substrate, and the thickness of the substrate of the transistor is less than or equal to the distance between the two adjacent substrates.

[0017] As can be seen, the radio frequency power amplifier of the present application comprises a transistor and a plurality of stacked substrates, the transistor is arranged between any two adjacent substrates except the topmost substrate, and the thickness of the substrate of the transistor is less than or equal to the distance between the two adjacent substrates, that is, one surface of the transistor is on the same surface as one of the two adjacent substrates, so that the electrical length from the emitter to the ground on the transistor is reduced, and the grounding inductance is reduced. In addition, since the transistor is not arranged on the topmost layer, the heat dissipation path is shortened, so that the heat dissipation resistance is reduced, the heat dissipation effect is improved, and the performance of the radio frequency power amplifier is enhanced.

[0018] In addition, the present application also provides an electronic device with the above advantages. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0020] Figure 1 The structure of the existing radio frequency power amplifier is shown in the figure;

[0021] Figure 2 A structure schematic diagram of a radio frequency power amplifier provided by an embodiment of the present application;

[0022] Figure 3 A structure schematic diagram of another radio frequency power amplifier provided by an embodiment of the present application;

[0023] Figure 4 A measurement result diagram of a ground inductance of an existing radio frequency power amplifier;

[0024] Figure 5 A measurement result diagram of a ground inductance of a radio frequency power amplifier provided by the present application;

[0025] Figure 6 A temperature distribution schematic diagram of an emitter of a heterojunction bipolar transistor in an existing radio frequency power amplifier;

[0026] Figure 7 A temperature distribution schematic diagram of each position on a center line of an emitter in an existing radio frequency power amplifier;

[0027] Figure 8 A temperature distribution schematic diagram on a heat dissipation path of an existing radio frequency power amplifier;

[0028] Figure 9 A temperature distribution schematic diagram of each position on a center line of a heat dissipation path of an existing radio frequency power amplifier;

[0029] Figure 10 A temperature distribution schematic diagram of an existing radio frequency power amplifier;

[0030] Figure 11 A temperature distribution schematic diagram of each position on a center line of each emitter array in an existing radio frequency power amplifier;

[0031] Figure 12 A temperature distribution schematic diagram of an emitter of a heterojunction bipolar transistor in a radio frequency power amplifier provided by the present application;

[0032] Figure 13 A temperature distribution schematic diagram of each position on a center line of an emitter provided by the present application;

[0033] Figure 14 A temperature distribution schematic diagram on a heat dissipation path of a radio frequency power amplifier provided by the present application;

[0034] Figure 15 A temperature distribution schematic diagram of each position on a center line of a heat dissipation path of a radio frequency power amplifier provided by the present application;

[0035] Figure 16A temperature distribution diagram of a radio frequency power amplifier provided by the present application;

[0036] Figure 17 A temperature distribution diagram of a radio frequency power amplifier provided by the present application. DETAILED DESCRIPTION

[0037] In order to make the personnel in the technical field better understand the present application, the present application is further described in detail below in combination with the drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without making creative efforts belong to the scope of protection of the present application.

[0038] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be practiced in other ways different from those described herein, and the person skilled in the art can make similar generalizations without departing from the connotation of the present application, therefore the present application is not limited by the specific embodiments disclosed below.

[0039] As described in the background section, in the current radio frequency power amplifier, the transistor is located on the upper surface of the top layer substrate, the electrical length of the emitter of the transistor to the ground is the thickness of the base of the transistor and the multilayer substrate, the electrical length is large, which leads to large ground inductance of the RF PA, which is sensitive to the ground, and because the transistor is located on the upper surface of the top layer substrate, the heat dissipation path of the emitter of the transistor passes through the via hole from the top layer to the bottom layer of the substrate, the heat dissipation effect is poor, which seriously affects the performance of the RF PA.

[0040] Therefore, the present application provides a radio frequency power amplifier, please refer to Figure 2 , Figure 2 A structural diagram of a radio frequency power amplifier provided by an embodiment of the present application, comprising:

[0041] The transistor 1 and the multilayer substrate 2 are stacked from bottom to top, the via holes 3 are distributed between the adjacent two layers of the substrate 2, the transistor 1 is located between any adjacent two layers of the substrate 2 except the top layer of the substrate 2, and the thickness of the substrate of the transistor 1 is less than or equal to the distance between the adjacent two layers of the substrate 2 where the transistor 1 is located.

[0042] It should be pointed out that the number of layers of the substrate 2 in the present application is not specifically limited, which is determined according to the situation. For example, the number of layers of the substrate 2 can be 4 layers, 6 layers, 8 layers, etc.

[0043] Optionally, the substrate 2 is any one of the following:

[0044] The organic substrate 2, a high-temperature co-fired ceramic (HTCC) substrate 2, and a low-temperature co-fired ceramic (LTCC) substrate 2.

[0045] Optionally, the transistor 1 is a hetero-junction bipolar transistor (HBT). Compared with other types of bipolar transistors, the hetero-junction bipolar transistor has better high-frequency signal characteristics, high base region emission efficiency, high linearity, high current density, low phase noise, and other excellent performances, thereby improving the performance of the radio frequency power amplifier. The hetero-junction bipolar transistor 1 as a chip of the radio frequency power amplifier can be, but is not limited to, a bare chip. In other embodiments of the present application, the transistor 1 can also be a bipolar junction transistor (BJT) or a field effect transistor (FET).

[0046] The number of transistors 1 can be one or more. When the number of transistors 1 is more than one, the plurality of transistors 1 are distributed in an array.

[0047] Specifically, the hetero-junction bipolar transistor at least includes a substrate, a buffer layer, a collector region, a base region, an emitter region, and an emitter. The emitter can be arranged in an array and dissipate heat through the substrate and the substrate 2.

[0048] The hetero-junction bipolar transistor 1 can be any of the following transistors:

[0049] A gallium arsenide hetero-junction bipolar transistor, a silicon germanium hetero-junction bipolar transistor, a gallium nitride hetero-junction bipolar transistor, and a pseudomorphic high electron mobility transistor (PHEMT).

[0050] It should be noted that the mounting method of the transistor 1 is not specifically limited in the present application and can be selected as desired. The mounting method of the transistor 1 is face-up mounting or face-down mounting, wherein the front surface of the transistor 1 is the surface on which the emitter is located. It should be pointed out that when the transistor 1 is a field effect transistor, the source, gate, and drain are located on the same surface of the field effect transistor, and the surface on which the emitter is located is the surface on which the source, gate, and drain are located. Figure 2The RF power amplifier shown is installed with the front facing up. A schematic diagram of the RF power amplifier's structure when installed with the front facing down is shown below. Figure 3 As shown, Figure 2 and Figure 3 Transistor 1 is a heterojunction bipolar transistor.

[0051] The radio frequency power amplifier of this application includes a transistor 1 and a multilayer substrate 2. The transistor 1 is located between any two adjacent substrates 2 except for the top layer, and the substrate thickness of the transistor 1 is less than or equal to the spacing between the two adjacent substrates 2. That is, one surface of the transistor 1 is on the same surface as one of the two adjacent substrates 2. Therefore, the electrical length from the emitter to ground on the transistor 1 is reduced, so the ground inductance is reduced. Furthermore, since the transistor 1 is not located on the top layer, the heat dissipation path is shortened, so the thermal resistance of the heat dissipation path is reduced, the heat dissipation effect is improved, and the performance of the radio frequency power amplifier is enhanced.

[0052] by Figure 2 Taking the RF power amplifier shown as an example, the grounding inductance and heat dissipation of the RF power amplifier in this application are compared with... Figure 1 A comparative explanation of existing RF power amplifiers is provided.

[0053] Figure 2 The RF power amplifier substrate has 4 layers. The heterojunction bipolar transistor is mounted face down between the bottom substrate and the second to last substrate. The emitter of the heterojunction bipolar transistor is directly attached to the grounding via on the bottom substrate.

[0054] Figure 1 and Figure 2 The thickness of the substrate is 300µm, and the thickness of the HBT is 75µm. Figure 1 The structure shown, and the measurement results of the ground inductance of the RF power amplifier are as follows: Figure 4 As shown, the vertical axis represents the grounding inductance, and the horizontal axis represents the frequency. The grounding inductance is approximately 0.38H. Figure 2 The structure shown, and the measurement results of the ground inductance of the RF power amplifier are as follows: Figure 5 As shown, the vertical axis represents the grounding inductance, and the horizontal axis represents the frequency. The grounding inductance is approximately 0.147H, which is twice the grounding inductance of existing technologies.

[0055] for Figure 1 The schematic diagram of the emitter temperature distribution of the heterojunction bipolar transistor shown is available for reference. Figure 6 , Figure 7This diagram shows the temperature distribution at various locations along the emitter centerline, ranging from approximately 1080K to 1170K. The vertical axis represents temperature, and the horizontal axis represents the position of the centerline point on the Z-axis, which runs along the emitter thickness. The heat dissipation path of the heterojunction bipolar transistor's emitter runs from the top through vias to the bottom substrate, and then to the lower surface of the bottom substrate. For the temperature distribution along this heat dissipation path, please refer to [reference needed]. Figure 8 , Figure 9 The temperature distribution at various locations along the center line of the heat dissipation path ranges from approximately 300K to 1200K. The vertical axis represents the temperature, and the horizontal axis represents the position of the point on the center line on the Z-axis, which runs from the bottom substrate to the top substrate.

[0056] Figure 1 The temperature distribution of the RF power amplifier shown is as follows: Figure 10 As shown, Figure 10 The emitters in the array are arranged in an array, designated A1, B1, C1, and D1. The temperature distribution at various locations along the center lines of the four columns A1, B1, C1, and D1 is as follows: Figure 11 As shown, the temperature range is approximately 295K to 350K, where the vertical axis represents the temperature and the horizontal axis represents the position of the center line point on the Z-axis.

[0057] for Figure 2 The schematic diagram of the emitter temperature distribution of the heterojunction bipolar transistor shown is available for reference. Figure 12 The emitter temperature range is approximately 425K to 510K. Figure 13 This diagram shows the temperature distribution at various locations along the emitter centerline, where the vertical axis represents temperature and the horizontal axis represents the position of a point on the centerline along the Z-axis, which runs along the emitter thickness. For the distribution along the heat dissipation path, please refer to [reference needed]. Figure 14 , Figure 15 The temperature distribution at various locations along the center line of the heat dissipation path is shown, with a temperature range of approximately 300K to 540K. The vertical axis represents the temperature, and the horizontal axis represents the position of the point on the center line on the Z-axis, which runs from the bottom substrate to the top substrate.

[0058] Figure 2 The temperature distribution of the RF power amplifier shown is as follows: Figure 16 As shown, Figure 16 The emitters in the array are arranged in an array, designated A2, B2, C2, and D2. The temperature distribution at various locations along the center lines of the four columns A2, B2, C2, and D2 is as follows: Figure 17 As shown, the temperature range is approximately 293K to 298K, where the vertical axis represents the temperature and the horizontal axis represents the position of the center line point on the Z-axis.

[0059] Depend on Figures 6 to 17It can be known that the heat dissipation effect of the radio frequency power amplifier is obviously enhanced, and the performance of the radio frequency power amplifier can be effectively improved.

[0060] The application further provides an electronic device comprising the radio frequency power amplifier of any one of the above embodiments.

[0061] The electronic device includes but is not limited to a mobile phone, a router, and various wireless communication devices thereof.

[0062] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts of each embodiment can be referred to each other. For the device disclosed by the embodiments, since it corresponds to the method disclosed by the embodiments, the description is relatively simple, and the related parts can be referred to the method part.

[0063] The radio frequency power amplifier and the electronic device provided by the application are described in detail above. The principles and implementation manners of the application are described by applying specific examples. The above embodiment is only used to help understand the method and the core idea of the application. It should be pointed out that the ordinary skilled in the art can make some improvements and modifications to the application without departing from the principles of the application. These improvements and modifications also fall within the protection scope of the claims of the application.

Claims

1. A radio frequency power amplifier, characterized by, The application relates to an electronic device comprising: a transistor and a plurality of substrates stacked one on top of another, a via being arranged between each pair of adjacent substrates, the transistor being arranged between any pair of adjacent substrates except the topmost pair of substrates, and the thickness of the substrate of the transistor being less than or equal to the distance between the pair of adjacent substrates in which the transistor is arranged, the number of transistors being a plurality and being arranged in an array; the transistor is a heterojunction bipolar transistor; the transistor is mounted with the front face facing downwards, the front face of the transistor being the surface on which the emitter is arranged; the heterojunction bipolar transistor is arranged between the bottommost substrate and the penultimate substrate, the emitter of the heterojunction bipolar transistor being directly attached to the ground via of the bottommost substrate; the via directly connects the two adjacent substrates.

2. The radio frequency power amplifier of claim 1, wherein, the heterojunction bipolar transistor is any one of: a gallium arsenide heterojunction bipolar transistor, a silicon germanium heterojunction bipolar transistor, a gallium nitride heterojunction bipolar transistor, a pseudomorphic high electron mobility transistor.

3. The radio frequency power amplifier of claim 1, wherein, the substrate is any one of: an organic substrate, a high-temperature co-fired ceramic substrate, a low-temperature co-fired ceramic substrate.

4. The radio frequency power amplifier of claim 1, wherein, the number of substrates is 4, 6 or 8.

5. An electronic device, comprising: the electronic device comprises a radio frequency power amplifier as claimed in any one of claims 1 to 4.

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