CN113507779A

CN113507779A - Packaging substrate for duplexer and duplexer

Info

Publication number: CN113507779A
Application number: CN202110844348.9A
Authority: CN
Inventors: 王鑫; 杨清华; 唐兆云; 赖志国
Original assignee: Suzhou Huntersun Electronics Co Ltd
Current assignee: Suzhou Huntersun Electronics Co Ltd
Priority date: 2021-07-26
Filing date: 2021-07-26
Publication date: 2021-10-15

Abstract

The present disclosure provides a package substrate for a duplexer. The duplexer includes a first inductor for a transmitting end and a second inductor for a receiving end. The package substrate according to the present disclosure includes: a plurality of metal layers for forming a first inductor and a second inductor; and a plurality of dielectric layers disposed between the plurality of metal layers, wherein a dielectric material characteristic of the dielectric layer between the metal layers for forming the first inductor and the metal layers for forming the second inductor is different from a dielectric material characteristic of the dielectric layer between the metal layers for forming the first inductor and the metal layers for forming the second inductor. According to the embodiment of the present disclosure, by forming the package carrier by overlapping different dielectric materials, mutual interference between the first inductor for the transmitting end and the second inductor for the receiving end can be reduced, thereby improving isolation.

Description

Packaging substrate for duplexer and duplexer

Technical Field

The present disclosure relates to the field of semiconductor technology, and in particular, to a package substrate for a duplexer and a duplexer including the same.

Background

With the development of wireless communication applications, the demand for data transmission rate is higher and higher, and the data transmission rate corresponds to high utilization rate of spectrum resources and spectrum complexity. The complexity of the communication protocol imposes strict requirements on various performances of the radio frequency system, and in the radio frequency front-end module, a radio frequency filter and a duplexer play a crucial role and can filter out-of-band interference and noise to meet the requirements of the radio frequency system and the communication protocol on the signal-to-noise ratio. With the increase of 5G commercial products, the demand of B1, 2, 3, 5, 7, 8 and other duplexers is increasing.

At present, filters and duplexers based on Film Bulk Acoustic Resonators (FBARs) are increasingly widely used due to their advantages of low insertion loss, steep transition characteristics, high selectivity, high power capacity, and strong anti-electrostatic discharge (ESD) capability. However, in the face of increasingly stringent frequency resources, the isolation of frequency selection devices such as filters and duplexers in the radio frequency front end to adjacent frequency bands is required to be higher.

Therefore, in order to improve the isolation between the receive (Rx) and transmit (Tx) bands of the duplexer, a method of increasing the inductance value of a wire-wound inductor on the package substrate or accessing a device such as an inductor or a capacitor is generally employed. However, this introduces more loss, degrading the insertion loss. And meanwhile, the device also needs to occupy larger volume, which is not beneficial to miniaturization development.

Therefore, there is still a need in the art for a package substrate for a duplexer, which can improve the isolation between Rx and Tx bands without changing the inductance and volume of the wire-wound inductor of the package substrate.

Disclosure of Invention

The following presents a simplified summary of the disclosure in order to provide a basic understanding of some aspects of the disclosure. It should be understood, however, that this summary is not an exhaustive overview of the disclosure, nor is it intended to identify key or critical elements of the disclosure, nor is it intended to be used to limit the scope of the disclosure. This summary is provided merely for the purpose of presenting some of the inventive concepts related to the disclosure in a simplified form as a prelude to the more detailed description that is presented later.

An object of the present disclosure is to provide a package substrate capable of improving isolation between Rx and Tx bands without changing inductance and volume of a wire-wound inductor, and a duplexer including the same.

According to an aspect of the present disclosure, there is provided a package substrate for a duplexer including a first inductor for a transmitting end and a second inductor for a receiving end, the package substrate including: a plurality of metal layers for forming a first inductor and a second inductor; and a plurality of dielectric layers disposed between the plurality of metal layers, wherein a dielectric material characteristic of the dielectric layer between the metal layers for forming the first inductor and the metal layers for forming the second inductor is different from a dielectric material characteristic of the dielectric layer between the metal layers for forming the first inductor and/or the dielectric layer between the metal layers for forming the second inductor.

According to embodiments of the present disclosure, the dielectric material property may include a dielectric constant.

According to embodiments of the present disclosure, the dielectric constant may be in the range of 2 to 15.

According to an embodiment of the present disclosure, a dielectric constant of a dielectric material for forming a dielectric layer between metal layers of the first inductor and a metal layer for forming the second inductor may be higher than a dielectric constant of a dielectric material for forming a dielectric layer between metal layers of the first inductor and/or a dielectric material for forming a dielectric layer between metal layers of the second inductor.

According to embodiments of the present disclosure, the metal layer used to form the first inductor may be different from the metal layer used to form the second inductor.

According to an embodiment of the present disclosure, the first inductor and the second inductor are arranged on opposite sides of the isolation strip being grounded.

According to another aspect of the present disclosure, there is provided a package substrate for a duplexer including a first inductor for a transmitting end and a second inductor for a receiving end, the package substrate including: the first metal layer, the second metal layer, the third metal layer, the fourth metal layer and the fifth metal layer are arranged from the top to the bottom in the vertical direction; and a first dielectric layer disposed between the first metal layer and the second metal layer, a second dielectric layer disposed between the second metal layer and the third metal layer, a third dielectric layer disposed between the third metal layer and the fourth metal layer, and a fourth dielectric layer disposed between the fourth metal layer and the fifth metal layer, wherein the first inductor is formed in the first metal layer and the second metal layer, and the second inductor is formed in the third metal layer and the fourth metal layer, or the second inductor is formed in the first metal layer and the second metal layer, and the first inductor is formed in the third metal layer and the fourth metal layer, and wherein a dielectric material characteristic of the second dielectric layer is different from a dielectric material characteristic of the first dielectric layer and/or the third dielectric layer.

According to an embodiment of the present disclosure, the dielectric constant of the dielectric material of the second dielectric layer may be higher than the dielectric constant of the dielectric material of the first dielectric layer and/or the third dielectric layer.

According to yet another aspect of the present disclosure, there is provided a duplexer including the package substrate according to the above aspect of the present disclosure.

According to still another aspect of the present disclosure, there is provided a method of manufacturing a package substrate for a duplexer including a first inductor for a transmitting end and a second inductor for a receiving end, the method including: forming a plurality of metal layers and a plurality of dielectric layers disposed between the plurality of metal layers; and forming a first inductor in some of the plurality of metal layers and a second inductor in other of the plurality of metal layers, wherein dielectric material properties of the dielectric layers between the metal layers forming the first inductor and the metal layers for forming the second inductor are different from dielectric material properties of the dielectric layers between the metal layers for forming the first inductor and/or the dielectric layers between the metal layers for forming the second inductor.

According to the package substrate and the duplexer including the same of the present disclosure, the isolation between the Rx and Tx bands can be improved without changing the inductance value and the volume of the wire-wound inductor.

Drawings

The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated into and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.

Fig. 1 illustrates an equivalent circuit diagram of an example of a duplexer to which a package substrate according to an embodiment of the present disclosure may be applied.

Fig. 2 illustrates a plan view of a package substrate according to an embodiment of the present disclosure.

Fig. 3 illustrates a perspective view of a package substrate according to an embodiment of the present disclosure.

Fig. 4 illustrates a cross-sectional view of a package substrate according to an embodiment of the present disclosure.

Fig. 5A to 5E respectively show diagrams of layouts of first to fifth metal layers of a package substrate according to an embodiment of the present disclosure.

Fig. 6 shows a graph of the isolation between Rx and Tx bands with respect to the dielectric constant of the second dielectric layer according to an embodiment of the present disclosure.

Fig. 7 shows a graph comparing isolation between Rx and Tx frequency bands according to an embodiment of the present disclosure and a comparative example.

Detailed Description

In this specification, it will also be understood that when an element is referred to as being "on," "connected to," or "coupled to" other elements relative to the other elements, such as on, "connected to," or "coupled to" the other elements, the one element may be directly on, connected or coupled to the one element, or an intervening third element may also be present. In contrast, when an element is referred to in this specification as being "directly on," "directly connected to," or "directly coupled to" other elements, relative to the other elements, there are no intervening elements provided therebetween.

The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Like numbers refer to like elements throughout. Also, in the drawings, the thickness, ratio and size of the components are exaggerated for clarity of illustration.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, "a," "an," "the," and "at least one" do not denote a limitation of quantity, but rather are intended to include both the singular and the plural, unless the context clearly dictates otherwise. For example, "an element" means the same as "at least one element" unless the context clearly dictates otherwise. "at least one of" should not be construed as limited to the quantity "one". "or" means "and/or". The term "and/or" includes any and all combinations of one or more of the associated listed items.

The terms "lower", "upper" and "upper" are used to describe the positional relationship of the components shown in the drawings. These terms may be relative concepts and are described based on the orientation presented in the figures.

Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms defined in commonly used dictionaries should be interpreted as having the same meaning as is in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The meaning of "comprising" or "comprises" indicates a property, a quantity, a step, an operation, an element, a component or a combination thereof, but does not exclude other properties, quantities, steps, operations, elements, components or combinations thereof.

Embodiments are described herein with reference to cross-sectional views that are idealized embodiments. Thus, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, regions shown or described as flat may typically have rough and/or nonlinear features. Also, the acute angles shown may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the claims.

Hereinafter, exemplary embodiments according to the present disclosure will be described with reference to the accompanying drawings.

Fig. 1 shows an equivalent circuit diagram of an example of a duplexer 100 to which a package substrate according to an embodiment of the present disclosure may be applied.

As shown in fig. 1, the duplexer 100 may include resonators B01 through B14 and matching inductors L01 through L09, wherein the inductors L01 through L03 are first inductors for a transmitting end (Tx) and the inductors L04 through L06 are second inductors for a receiving end (Rx). Those skilled in the art will recognize that although the duplexer 100 shown in fig. 1 has four series resonators and three parallel resonators with corresponding matching inductors at both the transmit and receive ends, the present disclosure is not so limited. Those skilled in the art can use other numbers and connection forms of resonators and corresponding matching inductors according to specific application scenarios and design requirements, and all variations are intended to be within the scope of the present disclosure.

According to an embodiment of the present disclosure, the first inductors L01 to L03 for Tx and the second inductors L04 to L06 for Rx may have the form of wire wound inductors formed in a package substrate of the duplexer.

Fig. 2 illustrates a plan view of a package substrate 200 according to an embodiment of the present disclosure. Fig. 3 illustrates a perspective view of a package substrate 200 according to an embodiment of the present disclosure. Fig. 4 illustrates a cross-sectional view of a package substrate 200 according to an embodiment of the present disclosure. Further, fig. 5A to 5E respectively show diagrams of layouts of the first to fifth metal layers M1 to M5 of the package substrate according to the embodiment of the present disclosure. It should be noted that fig. 5A to 5E respectively show the layouts of the first to fifth metal layers M1 to M5, in which individual hexagonal patterns represent metal vias provided in the dielectric layers and/or.

As shown in fig. 2 to 4, the package substrate 200 according to the embodiment of the present disclosure may include a first metal layer M1, a second metal layer M2, a third metal layer M3, a fourth metal layer M4, and a fifth metal layer M5, which are disposed from top to bottom in a vertical direction.

According to an embodiment of the present disclosure, the first to fifth metal layers M1 to M5 may be formed of a conductive metal material, which may include, but is not limited to, copper (Cu).

In addition, the package substrate 200 may include a first dielectric layer D1 disposed between the first metal layer M1 and the second metal layer M2, a second dielectric layer D2 disposed between the second metal layer M2 and the third metal layer M3, a third dielectric layer D3 disposed between the third metal layer M3 and the fourth metal layer M4, and a fourth dielectric layer D4 disposed between the fourth metal layer M4 and the fifth metal layer M5.

According to embodiments of the present disclosure, the first to fourth dielectric layers D1 to D4 may be formed of an insulating dielectric material, which may include, but is not limited to: GEA-705G, GH-200(D), GHPL-830NSF, GHPL-970LF, 6785GT-K, etc.

Those skilled in the art will recognize that although the embodiments of the present disclosure are described herein by way of example in which the package substrate 200 includes the first to fifth metal layers M1 to M5 and the first to fourth dielectric layers D1 to D4, the present disclosure is not limited thereto. Those skilled in the art can use other numbers of metal layers and corresponding dielectric layers depending on the application scenario and design needs, and all such variations are intended to be within the scope of the present disclosure.

According to an embodiment of the present disclosure, the first inductors L01 to L03 for Tx may be formed in the first metal layer M1 and the second metal layer M2, and the second inductors L04 to L06 for Rx may be formed in the third metal layer M3 and the fourth metal layer M4. For example, as shown in fig. 5A and 5B, the first inductors L01 to L03 for Tx in the form of wire wound inductors may be formed by the metal wiring in the first metal layer M1, the metal via between the first metal layer M1 and the second metal layer M2, and the metal wiring in the second metal layer M2. Further, for example, as shown in fig. 5C and 5D, the second inductors L04 to L06 for Rx may be formed to have the form of a wire-wound inductor by a metal wiring in the third metal layer M3, a metal via between the third metal layer M3 and the fourth metal layer M4, and a metal wiring in the fourth metal layer M4.

However, one skilled in the art will recognize that embodiments of the present disclosure are not particularly limited with respect to the metal layers used to form inductors L01-L06. In other words, the second inductors L04 to L06 for Rx may also be formed in the first and second metal layers M1 and M2, and the first inductors L01 to L03 for Tx may also be formed in the third and fourth metal layers M3 and M4.

In addition, according to an embodiment of the present disclosure, the package substrate 200 may further include a grounded isolation strip IS. As shown in fig. 2 to 4, the isolation strips IS grounded may be disposed in the first to fourth metal layers M1 to M4 and the first to fourth dielectric layers D1 to D4. Further, according to the embodiment of the present disclosure, the first inductors L01 to L03 and the second inductors L04 to L06 are disposed at opposite sides of the isolation strip IS grounded. In this way, the mutual inductive coupling between the first inductor and the second inductor may be reduced, thereby improving the isolation between the Rx and Tx bands.

According to an embodiment of the present disclosure, as shown in fig. 2 to 4, the grounded isolation strip IS may be connected to the grounded fifth metal layer M5 by extending through the first to fourth metal layers M1 to M4 and the first to fourth dielectric layers D1 to D4 by means of vias in a vertical direction.

Further, according to the embodiment of the present disclosure, the metal layers for forming the first inductors L01 to L03 are different from the metal layers for forming the second inductors L04 to L06, that is, the first inductors L01 to L03 and the second inductors L04 to L06 are formed in different metal layers from each other. This may further reduce the mutual inductive coupling between the first inductor and the second inductor, thereby improving the isolation between the Rx and Tx bands.

According to an embodiment of the present disclosure, dielectric material characteristics of a dielectric layer (e.g., D2) between a metal layer (e.g., M2) for forming first inductors L01 through L03 and a metal layer (e.g., M3) for forming second inductors L04 through L06 are different from dielectric material characteristics of a dielectric layer (e.g., D1) between metal layers (e.g., M1 and M2) for forming first inductors L01 through L03 and a dielectric layer (e.g., D3 and D4) between metal layers (e.g., M3, M4 and M5) for forming second inductors L04 through L06.

That is, according to an embodiment of the present disclosure, the dielectric material characteristics of the second dielectric layer D2 may be different from those of the first dielectric layer D1 and/or the third dielectric layer D3. In addition, according to an embodiment of the present disclosure, the dielectric material characteristics of the second dielectric layer D2 may also be different from those of the fourth dielectric layer D4. According to embodiments of the present disclosure, the dielectric material property may include a dielectric constant. According to embodiments of the present disclosure, the dielectric constant may be in the range of 2 to 15.

According to an embodiment of the present disclosure, a dielectric constant of a dielectric material of a dielectric layer (e.g., D2) between metal layers (e.g., M2) for forming first inductors L01 through L03 and metal layers (e.g., M3) for forming second inductors L04 through L06 may be higher than a dielectric constant of a dielectric layer (e.g., D1) between metal layers (e.g., M1 and M2) for forming first inductors L01 through L03 and/or a dielectric layer (e.g., D3) between metal layers (e.g., M3 and M4) for forming second inductors L04 through L06.

That is, according to an embodiment of the present disclosure, the dielectric constant of the dielectric material of the second dielectric layer D2 may be higher than the dielectric constant of the dielectric material of the first dielectric layer D1 and/or the third dielectric layer D3. For example, the first dielectric layer D1 and the third dielectric layer D3 may be formed of the same dielectric material having a dielectric constant of 3.7, and the second dielectric layer D2 may be formed of a different dielectric material having a dielectric constant of 10. Preferably, the fourth dielectric layer D4 may be formed of the same dielectric material as the first dielectric layer D1 and the third dielectric layer D3, and thus have a dielectric constant of 3.7.

The graph of fig. 6 was plotted by keeping the dielectric constants of the dielectric materials of the first dielectric layer D1, the third dielectric layer D3, and the fourth dielectric layer D4 constant at 3.7 and making the dielectric constant of the dielectric material of the second dielectric layer D2 values at 3.7, 4.5, and 10, respectively. As can be seen from fig. 6, as the dielectric constant of the dielectric material of the second dielectric layer D2 increases, the isolation between the Rx and Tx frequency bands increases accordingly.

The dielectric layers between the metal layers in the comparative example used in the graph of fig. 7 are made of the same dielectric material and have the same dielectric material characteristics. For example, each dielectric layer has the same dielectric constant.

The solid line in fig. 7 represents the isolation between the Rx and Tx bands of the comparative example, and the dotted line in fig. 7 represents the isolation between the Rx and Tx bands according to the embodiment of the present disclosure. As shown in fig. 7, the isolation between the Rx and Tx bands according to the embodiment of the present disclosure is significantly better than that of the comparative example.

According to still another aspect of the present disclosure, there is also provided a duplexer including the package substrate according to the above embodiment of the present disclosure.

According to still another aspect of the present disclosure, there is also provided a method of manufacturing a package substrate for a duplexer including a first inductor for a transmitting end and a second inductor for a receiving end, the method including: forming a plurality of metal layers and a plurality of dielectric layers disposed between the plurality of metal layers; and forming a first inductor in some of the plurality of metal layers and a second inductor in other of the plurality of metal layers, wherein dielectric material properties of the dielectric layers between the metal layers forming the first inductor and the metal layers for forming the second inductor are different from dielectric material properties of the dielectric layers between the metal layers for forming the first inductor and/or the dielectric layers between the metal layers for forming the second inductor.

Although the present disclosure has been described with reference to exemplary embodiments thereof, those skilled in the art will appreciate that various modifications and changes may be made without departing from the spirit and scope of the present disclosure as set forth in the claims.

Claims

1. A package substrate for a duplexer, the duplexer comprising a first inductor for a transmitting end and a second inductor for a receiving end, the package substrate comprising:

a plurality of metal layers for forming the first inductor and the second inductor; and

a plurality of dielectric layers disposed between the plurality of metal layers,

wherein a dielectric material characteristic of a dielectric layer between metal layers used to form the first inductor and metal layers used to form the second inductor is different from a dielectric material characteristic of a dielectric layer between metal layers used to form the first inductor and/or a dielectric layer between metal layers used to form the second inductor.

2. The package substrate of claim 1, wherein the dielectric material characteristic comprises a dielectric constant.

3. The package substrate of claim 2, wherein the dielectric constant is in a range of 2 to 15.

4. The package substrate of claim 1 or 2, wherein a dielectric constant of a dielectric material used to form a dielectric layer between the metal layers of the first inductor and the metal layers of the second inductor is higher than a dielectric constant of a dielectric material used to form a dielectric layer between the metal layers of the first inductor and/or a dielectric material used to form a dielectric layer between the metal layers of the second inductor.

5. The package substrate of claim 1 or 2, wherein a metal layer used to form the first inductor is different from a metal layer used to form the second inductor.

6. The package substrate of claim 1 or 2, wherein the first inductor and the second inductor are disposed on opposite sides of a grounded isolation strip.

7. A package substrate for a duplexer, the duplexer comprising a first inductor for a transmitting end and a second inductor for a receiving end, the package substrate comprising:

the first metal layer, the second metal layer, the third metal layer, the fourth metal layer and the fifth metal layer are arranged from the top to the bottom in the vertical direction; and

a first dielectric layer disposed between the first metal layer and the second metal layer, a second dielectric layer disposed between the second metal layer and the third metal layer, a third dielectric layer disposed between the third metal layer and the fourth metal layer, and a fourth dielectric layer disposed between the fourth metal layer and the fifth metal layer,

wherein the first inductor is formed in the first metal layer and the second inductor is formed in the third metal layer and the fourth metal layer, or the second inductor is formed in the first metal layer and the second metal layer and the first inductor is formed in the third metal layer and the fourth metal layer, and

wherein the dielectric material characteristics of the second dielectric layer are different from the dielectric material characteristics of the first dielectric layer and/or the third dielectric layer.

8. The package substrate of claim 7, wherein the dielectric material characteristic comprises a dielectric constant.

9. The package substrate of claim 7 or 8, wherein the first inductor and the second inductor are disposed on opposite sides of a grounded isolation strip.

10. The package substrate of any of claims 7 or 8, wherein the dielectric constant of the dielectric material of the second dielectric layer is higher than the dielectric constant of the dielectric material of the first dielectric layer and/or the third dielectric layer.

11. A duplexer comprising the package substrate according to any one of claims 1 to 10.

12. A method of manufacturing a package substrate for a duplexer including a first inductor for a transmitting end and a second inductor for a receiving end, the method comprising:

forming a plurality of metal layers and a plurality of dielectric layers disposed between the plurality of metal layers; and

forming the first inductor in some of the plurality of metal layers and the second inductor in others of the plurality of metal layers,

wherein dielectric material characteristics of a dielectric layer between metal layers forming the first inductor and a metal layer forming the second inductor are different from dielectric material characteristics of a dielectric layer between metal layers forming the first inductor and/or a dielectric layer between metal layers forming the second inductor.

13. The method of claim 12, wherein the first inductor and the second inductor are disposed on opposite sides of a grounded isolation strip.