WO2020177849A1

WO2020177849A1 - A unibody for an electronic device

Info

Publication number: WO2020177849A1
Application number: PCT/EP2019/055268
Authority: WO
Inventors: Janne Ilvonen; Harri Lasarov; Alexander Khripkov; Dong Liu; Hongting Luo
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2019-03-04
Filing date: 2019-03-04
Publication date: 2020-09-10
Also published as: CN113519127B; CN113519127A

Abstract

A unibody (1) for an electronic device, the unibody (1) comprising at least three adjoining material layers (2) and at least one electronic circuitry (3). Each material layer (2) comprises at least one of a conductive material and a dielectric material. One of the material layers (2) is a frame layer (2a), and at least one of the material layers (2) is an at least partially conductive layer (2b). At least two of the material layers (2) are connected by means of conductive interconnection joints (4), and at least part of the electronic circuitry (3) is embedded in at least one of the material layers (2). The unibody is mechanically strong, easy to assemble, and provides more space for antennas, hence improving the performance of the antennas as well as allowing more antennas to be fitted into the same space.

Description

A UNIBODY FOR AN ELECTRONIC DEVICE

TECHNICAL FIELD

The disclosure relates to a unibody for an electronic device.

BACKGROUND

Future mobile electronic devices need to support millimeter-wave bands, e.g. 24 GHz, 28 GHz and 42 GHz, as well as sub-6 GHz bands in order to accommodate increased data rates. However, the volume reserved for all the antennas in a mobile electronic device is very limited and the added millimeter-wave antennas should ideally be accommodated to the same volume as the sub-6 GHz antennas. Increasing the volume reserved for antennas would make the electronic device larger, bulkier, and less attractive to users. Current millimeter-wave antennas either require such additional volume, or if placed in the same volume, significantly reduce the efficiency of sub-6 GHz antennas.

Furthermore, the movement towards very large displays, covering as much as possible of the electronic device, makes the space available for the antenna array very limited, forcing either the size of the antenna array to be significantly reduced, and its performance impaired, or a large part of the display to be inactive.

Additionally, large openings in the body of the mobile electronic devices are undesirable since they weaken the mechanical structure of the body, make manufacture and assembly more difficult, and makes the appearance of the device less attractive to users.

SUMMARY

The foregoing and other objects are achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims, the description, and the figures.

According to a first aspect, there is provided a unibody for an electronic device, the unibody comprising at least three adjoining material layers and at least one electronic circuitry, each material layer comprising at least one of an conductive material and a dielectric material, one of the material layers being a frame layer, at least one of the material layers being an at least partially conductive layer, at least two of the material layers being directly interconnected by means of conductive interconnection joints, and at least part of the electronic circuitry being embedded in at least one of the material layers.

This layered structure allows the conductive layers to be thin and arbitrarily shaped, and as a consequence thereof interconnections, electronic circuitry, and radio frequency elements can be embedded within the layered structure. One implementation may be an antenna, which is embedded to the layered structure, hence improving the performance of the antennas as well as allowing more antennas to be fitted into the same space. Therefore, this solution facilitates a layered structure which is mechanically strong, easy to assemble, and which provides more space for electronic circuitry.

In a possible implementation form of the first aspect, at least one of the material layers is an at least partially dielectric layer, facilitating a stable structure wherein any conductive layers are at least partially separated.

In a further possible implementation form of the first aspect, the frame layer is an at least partially conductive layer. The layering allows individual conductive layers to be thin and arbitrarily shaped, which allows integration of electronic circuitry into the frame.

Furthermore, a thin frame layer is easier to provide with, e.g., micro perforations compared to conventional thicker frames.

In a further possible implementation form of the first aspect, the frame layer comprises at least part of the electronic circuitry, the electronic circuitry reinforcing the unibody and, correspondingly, the unibody protecting the electronic circuitry.

In a further possible implementation form of the first aspect, the frame layer is at least partially radio frequency transparent, allowing radiation from e.g. the sub6GHz and mmWave antenna to pass uninhibitedly through the frame layer.

In a further possible implementation form of the first aspect, at least one conductive layer is a metal core layer, providing the unibody with increased rigidity. In a further possible implementation form of the first aspect, at least two of the material layers are at least partially conductive layers, each at least partially conductive layer being directly interconnected with at least one further at least partially conductive layer. The plurality of conductive layers increases the rigidity of the unibody and enables desired current paths, such that desired radio frequency elements can be formed.

In a further possible implementation form of the first aspect, the at least partially conductive layers are separated by at least one at least partially dielectric layer, providing insulation between conductive layers and/or facilitating antenna cuts and similar.

In a further possible implementation form of the first aspect, the unibody further comprises a surface coating layer adjoining a side of the frame layer not adjoining a further material layer, allowing the exterior of the unibody to be provided with a desired appearance or a protective coating.

In a further possible implementation form of the first aspect, at least one of the material layers comprises at least one of a plate section and a rim section, facilitating a unibody specifically configured to an individual electronic device.

In a further possible implementation form of the first aspect, the rim section extends from a periphery of the plate section in a direction essentially perpendicular to a main plane of the plate section, facilitating a configuration which is very stable and which encloses, supports, and protects all interior components.

In a further possible implementation form of the first aspect, at least one at least partially conductive layer comprises at least one conductive structure, the conductive structure comprising at least one radio frequency element, allowing radio frequency elements and hidden structures such as antenna cuts to be embedded directly into the unibody.

In a further possible implementation form of the first aspect, at least two at least partially conductive layers comprise one and the same conductive structure, the conductive structure comprising at least one radio frequency element, allowing the conductive structures to have any suitable shape and dimensions including a depth towards the interior of the unibody.

In a further possible implementation form of the first aspect, the radio frequency element is one of an antenna radiator, an antenna cut, a parasitic antenna element, a reflector or director for mmWave antenna, a wavetrap for sub6G or mmWave antenna, a transmission line, a power divider, a soldering pad, a connector, an IC component, a PCB trace, a CPU, a GPU, a RAM, a switch, a feedline, and a resonator, allowing a wide range of radio frequency element to be embedded within the unibody.

According to a second aspect, there is provided an electronic device comprising at least a display and unibody according to the above, wherein the unibody comprises at least three adjoining material layers, one material layer being a frame layer and one material layer being an at least partially conductive layer comprising electronic circuitry, the display and the frame layer at least partially forming an exterior of the electronic device.

This layered structure facilitates a unibody which is mechanically strong, easy to assemble, and which provides more space for antennas, hence improving the performance of the antennas as well as allowing more antennas to be fitted into the same space. Furthermore, complete integration of e.g. antennas and transmission lines is provided.

In a possible implementation form of the second aspect, the frame layer comprises a metal frame and at least one at least partially conductive layer comprises at least one antenna array, the layering allowing the individual conductive layers to be thin which, in combination with embedding conductive structures such as antenna arrays, reduces the volume required for forming a functional electronic device.

In a further possible implementation form of the second aspect, at least one material layer comprises at least one of a battery, a further antenna array, a printed circuit board, a coaxial cable, an RFIC, and an antenna connection, the embedding of components into material layers freeing up space for antennas, which improves the performance of the antennas as well as allows more antennas to be fitted into the same space.

This and other aspects will be apparent from and the embodiments described below.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed portion of the present disclosure, the aspects, embodiments and implementations will be explained in more detail with reference to the example embodiments shown in the drawings, in which: Fig. la shows a top view of a unibody in accordance with one embodiment of the present invention;

Fig. lb shows an exploded view of a unibody in accordance with a further embodiment of the present invention; Fig. lc shows a side view of a unibody in accordance with yet another embodiment of the present invention;

Fig. 2 shows a schematic illustration of a plurality of material layers of a unibody;

Fig. 3a shows a cross-sectional view of an electronic device comprising a unibody in accordance with one embodiment of the present invention; Fig. 3b shows a cross-sectional view of an electronic device comprising a unibody in accordance with a further embodiment of the present invention;

Fig. 4a shows a partial, cross-sectional view of a unibody in accordance with one embodiment of the present invention;

Fig. 4b shows a partial, cross-sectional view of a unibody in accordance with a further embodiment of the present invention;

Fig. 4c shows a partial, cross-sectional view of a unibody in accordance with a further embodiment of the present invention;

Figs. 5a to 5c shows schematic, cross-sectional illustration of a plurality of material layers of a unibody, each illustration comprising a different conductive structure. Fig. 6 shows a partial, perspective view of a unibody in accordance with a further embodiment of the present invention.

DETAILED DESCRIPTION

Figs. 3a and 3b show an electronic device 10 comprising a display 11 and a unibody 1. The unibody 1 comprises a plurality of adjoining material layers 2, at least one of the material layers forming an outer frame layer 2a. The display 11 and the frame layer 2a at least partially form the outer surface of the electronic device 10. Fig. 3a shows an embodiment where the display 11 and the frame layer 2a make up the entire outer surface of the electronic device 10. Fig. 3a shows an embodiment where the display 11 and the frame layer 2a make up only part of the outer surface of the electronic device 10, the remainder of the outer surface being made up of e.g. a back cover located opposite to the display 11.

The unibody 1, as shown in Figs la and lb comprises at least three adjoining material layers 2 and at least one electronic circuitry 3. Fig. lb shows 10 material layers 2. The electronic circuitry 3 may comprise batteries, integrated circuits, printed circuit boards, speakers, cameras, vibration motors etc. The unibody 1 may be formed by adhering material layers 2 to each other by means of an adhesive, by depositing layers onto each other e.g. by means of 3D printing, or by injection molding. Regardless of the chosen approach, one conductive layer 2b forms the starting point, and the remaining layers 2a, 2b, 2c are added to form the unibody.

Each material layer 2 comprises at least one of a conductive material and a dielectric material, i.e. the material layer 2 may comprise of either conductive material, dielectric material, or a combination of conductive material and dielectric material. The dielectric material in adjoining material layers 2 may overlap such that the individual dielectric sections of adjoined material layers 2 together form a cavity 12, located in a conductive surrounding, the cavity 12 being filled with dielectric material. This is shown in Figs. 4a, 4b, and 4c. The cavity 12 itself may form part of a conductive structure 8, which will be discussed in more detail below.

The conductive structures 8 includes feedlines, antennas, resonators and filters. The radio frequency functionality of the conductive structures 8 includes antenna radiator or cut, parasitic antenna element, reflector or director for mmWave antenna, wavetrap for sub6G or mmWave antenna, transmission line, power divider etc., soldering pad(s) for lumped element(s)/connector(s)/IC component(s) etc., or PCB traces for IC components.

One of the above-mentioned material layers 2 is a frame layer 2a. In some embodiments, the frame layer 2a may form the very outermost surface of the unibody. In alternative

embodiments, the outermost surface of the unibody 1 is formed by a surface coating layer 5 applied onto the frame layer 2a, on the side of the frame layer 2a which does not adjoin a further material layer 2, see e.g. Fig. lb. The surface coating layer 5 may comprise metal, ceramic, plastic, glass, fiber coatings etc. At least one of the material layers 2, including the frame layer 2a, is an at least partially conductive layer 2b. The conductive section of the conductive layer 2b may comprise of at least one metal such as aluminum, copper, or gold.

At least two of the material layers 2 are connected by means of conductive interconnection joints 4, as shown in Fig. 4a and 4b. The conductive interconnection joints 4 are configured to form multiple regions within the unibody 1 , which regions are mutually electromagnetically isolated and configured as various electronic circuitry 3 features.

In one embodiment, the regions within the unibody 1 and their respective conductive interconnection joints 4 accommodate the transmission lines which interconnect electronic circuitry 3, conductive structures 8, and/or radio frequency elements 9.

In some embodiments, conductive interconnection joints 4 extending through the dielectric layer 2c between adjacent conductive layers 2b are configured as an opening 13 in the dielectric layer 2c. The opening 13, shown in Fig. 4a, is made conductive by electroplating, insertion of the conductive shafts, conductive foil films, liquid conductive pastes or other conductive substances.

In one embodiment, the dielectric layer 2c is patterned with open surfaces 14 so that adjacent conductive layers 2b are in direct contact through the open surfaces 14 of the dielectric layer 2c, as shown in Fig. 4b).

In one embodiment, shown in Fig. 4b, the dielectric layer 2c is applied to the conductive layers 2b (A) by a lamination process, printing, spraying, or by using other processes.

Masking and etching processes (B) could be applied for the fabrication of the open surfaces 14 of the dielectric layer 2c. Metal deposition processes (C) may be utilized for fabrication of the non- via conductive interconnection joints 4 and the adjacent conductive layers 2b. In a further embodiment, vacuum deposition processes such as physical vapor deposition, chemical vapor deposition, roll-to-roll surface metallization or related processes may be utilized.

At least part of the electronic circuitry 3 is embedded in at least one of the material layers 2, e.g. the battery as shown in Figs la and lc. In one embodiment, the frame layer 2a comprises at least part of the conductive structures 8, as shown in Fig. 6. At least one of the material layers 2, including the frame layer 2a, is an at least partially dielectric layer 2c. The dielectric layer 2c may form a substrate for carrying the above- mentioned electronic circuitry 3 and/or radio frequency elements 9 such integrated circuits IC. The dielectric layer 2c may comprise of at least one of FR4, plastic, ceramic, carbon fiber, glass, or their composite materials.

In one embodiment, the frame layer 2a is an at least partially conductive layer 2b. In a further embodiment, the frame layer 2a is at least partially radio frequency transparent, as shown in Fig. 6.

Any material layer 2, including the frame layer 2a, may comprise completely of a conductive material, i.e. be only a conductive layer 2b. The material layer 2 may comprise completely of a dielectric material, i.e. be only a dielectric layer 2c. Furthermore, the material layer 2 may comprise of both a conductive material and a dielectric material, i.e. be a conductive layer 2b as well as a dielectric layer 2c, as shown in Figs. 5 to 5c.

At least one of the conductive layers 2b may be a metal core layer, as shown in Fig. 3a, reinforcing the unibody and making it more rigid.

In one embodiment, at least two of the material layers 2 are at least partially conductive layers 2b, and each at least partially conductive layer 2b is directly interconnected with at least one further at least partially conductive layer 2b. Fig. 4a shows, towards the left, four conductive layers 2b interconnected by conductive interconnection joints 4. Fig. 4a shows, towards the right, two conductive layers 2b interconnected by conductive interconnection joints 4.

The at least partially conductive layers 2b may be separated by at least one at least partially dielectric layer 2c, as shown in Figs lb and 4a.

In one embodiment, at least one of the material layers 2 comprises at least one of a plate section 6 and a rim section 7. Fig. 3a shows an embodiment wherein the unibody 1 comprises a plate section 6 and a rim section 7, the rim section 7 extending from a periphery of the plate section 6 in a direction essentially perpendicular to a main plane of the plate section 6. The rim section being connected to the display 11 around and edge farthest from the plate section 6. In such an embodiment, the unibody 1 may comprise all components located within the electronic device 10, such as battery and printed circuit boards. Fig. 3b shows an embodiment wherein the unibody 1 comprises only a rim section 7, such that the unibody 1 forms a peripheral frame extending, e.g., between a display 11 and a back cover. In such an embodiment, at least some of the components located within the electronic device 10, such as battery and printed circuit boards, are enclosed by the unibody 1 , the display 11 , and the back cover.

At least one at least partially conductive layer 2b may comprise at least one conductive structure 8, the conductive structure 8 comprising at least one radio frequency element 9. Fig. lc shows a unibody 1 comprising a plurality of conductive structures 8 in the form of mmWave antenna arrays or sub6G antennas. Figs. 5a to 5c show different embodiments of a unibody 1 comprising one top surface coating layer 5 and three material layers 2. Each embodiment comprises a conductive structure 8 comprising at least one radio frequency element 9. Fig. 5a shows a conductive structure 8, formed across the two bottom material layers 2, comprising a radio frequency element 9 in the form of a director in the second last layer, as well as a radio frequency element 9 in the form of a reflector, in the last layer. Fig.

5b shows a conductive structure 8, formed across the three material layers 2, comprising radio frequency elements 9 in the form of hidden sub-6G antenna cuts. Fig. 5c shows a conductive structure 8, formed across the two bottom material layers 2, comprising radio frequency elements 9 in the form of mmWave antennas in the second last layer, as well as radio frequency elements 9 in the form of a reflector and feed lines, in the last layer.

As shown in Figs. 4a to 5b, at least two at least partially conductive layers 2b may comprise one and the same conductive structure 8. A conductive structure 8 may also be limited completely to only one material layer 2, such as e.g. a conductive layer 2b comprising radio frequency elements 9 in the form of transmission lines.

The radio frequency elements 9 may be one, or several, of an antenna radiator, an antenna cut, a parasitic antenna element, a reflector or director for mmWave antenna, a wavetrap for sub6G or mmWave antenna, a transmission line, a power divider, a soldering pad, a connector, an IC component, a PCB trace, a CPU, a GPU, a RAM, a switch, a feedline, and a resonator. Figs la and lb show a plurality of radio frequency elements 9 embedded in at least one dielectric layer 2c.

As mentioned, the present invention also relates to an electronic device 10 comprising a display 11 and a unibody 1. The unibody 1 comprises at least three adjoining material layers 2, one material layer being a frame layer 2a and one material layer being an at least partially conductive layer 2b comprising electronic circuitry 3. The display 11 and the frame layer 2a at least partially form the outer surface of the electronic device 10.

In one embodiment, the frame layer 2a comprises a metal frame and at least one at least partially conductive layer 2b comprises at least one antenna array, as shown in Fig. lc. The at least one material layer 2 may comprise at least one of a battery, a further antenna array, a printed circuit board, a coaxial cable, an RFIC, and an antenna connection.

The various aspects and implementations has been described in conjunction with various embodiments herein. However, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed subject-matter, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article“a” or“an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. The reference signs used in the claims shall not be construed as limiting the scope.

Claims

1. A unibody (1) for an electronic device, said unibody (1) comprising at least three adjoining material layers (2) and at least one electronic circuitry (3), each material layer (2) comprising at least one of a conductive material and a dielectric material, one of said material layers (2) being a frame layer (2a), at least one of said material layers (2) being an at least partially conductive layer (2b), at least two of said material layers (2) being directly interconnected by means of conductive interconnection joints (4), and at least part of said electronic circuitry (3) being embedded in at least one of said material layers (2).

2. The unibody (1) according to claim 1, wherein at least one of said material layers (2) is an at least partially dielectric layer (2c).

3. The unibody (1) according to claim 1 or 2, wherein said frame layer (2a) is an at least partially conductive layer (2b).

4. The unibody (1) according to any one of the previous claims, wherein said frame layer (2a) comprises at least part of said electronic circuitry (3).

5. The unibody (1) according to any one of the previous claims, wherein said frame layer (2a) is at least partially radio frequency transparent.

6. The unibody (1) according to any one of the previous claims, wherein at least one conductive layer (2b) is a metal core layer.

7. The unibody (1) according to any one of the previous claims, wherein at least two of said material layers (2) are at least partially conductive layers (2b), each at least partially conductive layer (2b) being directly interconnected with at least one further at least partially conductive layer (2b).

8. The unibody (1) according to claim 7, wherein said at least partially conductive layers (2b) are separated by at least one at least partially dielectric layer (2c).

9. The unibody (1) according to any one of the previous claims, further comprising a surface coating layer (5) adjoining a side of said frame layer (2a) not adjoining a further material layer (2)·

10. The unibody (1) according to any one of the previous claims, wherein at least one of said material layers (2) comprises at least one of a plate section (6) and a rim section (7).

11. The unibody (1) according to claim 10, wherein said rim section (7) extends from a periphery of said plate section (6) in a direction essentially perpendicular to a main plane of said plate section (6).

12. The unibody (1) according to any one of the previous claims, wherein at least one at least partially conductive layer (2b) comprises at least one conductive structure (8), said conductive structure (8) comprising at least one radio frequency element (9).

13. The unibody (1) according to any one of the previous claims, wherein at least two at least partially conductive layers (2b) comprise one and the same conductive structure (8), said conductive structure (8) comprising at least one radio frequency element (9).

14. The unibody (1) according claim 12 or 13, wherein said radio frequency element (9) is one of an antenna radiator, an antenna cut, a parasitic antenna element, a reflector or director for mmWave antenna, a wavetrap for sub6G or mmWave antenna, a transmission line, a power divider, a soldering pad, a connector, an IC component, a PCB trace, a CPU, a GPU, a RAM, a switch, a feedline, and a resonator.

15. An electronic device (10) comprising at least a display (11) and a unibody (1) according to any one of claims 1 to 14, wherein said unibody (1) comprises at least three adjoining material layers (2), one material layer being a frame layer (2a) and one material layer being an at least partially conductive layer (2b) comprising electronic circuitry (3), said display (11) and said frame layer (2a) at least partially forming an outer surface of said electronic device (10).

16. The electronic device according to claim 15, wherein said frame layer comprises a metal frame and at least one at least partially conductive layer comprises at least one antenna array.

17. The electronic device according to claim 15 or 16, wherein said at least one material layer comprises at least one of a battery, a further antenna array, a printed circuit board, a coaxial cable, an RFIC, and an antenna connection.