US-12628276-B2 - Integral electronic stack

US12628276B2US 12628276 B2US12628276 B2US 12628276B2US-12628276-B2

Abstract

The disclosure relates to an integral electronic stack and a multi-layer stack. Specifically, according to an embodiment of the disclosure, there is provided an integral electronic stack for grounding an electrically conductive component in which passive intermodulation (PIM) is reduced, wherein the integral electronic stack includes a first integral stack and a second integral stack, the first integral stack being bonded to the second integral stack, wherein the first integral stack includes: a first board which is substantially rigid; a first electrically conductive layer which is disposed on at least part of a first main surface of the first board; a first electrically conductive adhesive layer and a second electrically conductive adhesive layer; and a first electrically conductive film which is disposed between the first electrically conductive adhesive layer and the second electrically conductive adhesive layer, and is bonded to the first electrically conductive adhesive layer and the second electrically conductive adhesive layer, respectively, the first electrically conductive adhesive layer and the second electrically conductive adhesive layer including a plurality of electrically conductive elements substantially distributed in an electrically insulative material, wherein the first electrically conductive adhesive layer bonds the first electrically conductive film to the one or more first electrically conductive layer.

Inventors

Jeongwan Choi
Jong-pil Kim
Jinbae KIM
Jeffrey W. McCutcheon

Assignees

3M INNOVATIVE PROPERTIES COMPANY

Dates

Publication Date: 20260512
Application Date: 20221005
Priority Date: 20211014

Claims (10)

1 . An integral electronic stack for grounding an electrically conductive component in which passive intermodulation (PIM) is reduced, wherein the integral electronic stack comprises a first integral stack and a second integral stack, the first integral stack being bonded to the second integral stack, wherein the first integral stack comprises: a first board which is substantially rigid: a first electrically conductive layer which is disposed on at least part of a first main surface of the first board; a first electrically conductive adhesive layer and a second electrically conductive adhesive layer; and a first electrically conductive film which is disposed between the first electrically conductive adhesive layer and the second electrically conductive adhesive layer, and is bonded to the first electrically conductive adhesive layer and the second electrically conductive adhesive layer, respectively, the first electrically conductive adhesive layer and the second electrically conductive adhesive layer comprising a plurality of electrically conductive elements substantially distributed in an electrically insulative material, wherein the first electrically conductive adhesive layer bonds the first electrically conductive film to the one or more first electrically conductive layers, wherein the second integral stack comprises: an electrically conductive second board which is substantially rigid: a third electrically conductive adhesive layer which comprises a plurality of electrically conductive elements substantially distributed in an electrically insulative material; and a flexible metal film which is bonded to at least part of a first main surface of the second board through the third electrically conducive adhesive layer, wherein the first integral stack and the second integral stack are bonded to each other by the second electrically conductive adhesive layer which is bonded to the flexible metal film disposed opposite the third electrically conductive adhesive layer, and electrically connect the first electrically conductive layer to the second board.
2 . The integral electronic stack of claim 1 , wherein the second board comprises one or more of stainless steel, aluminum (Al), galvanized aluminum, magnesium (Mg), an alloy of magnesium and aluminum, iron (Fe), zinc (Zn), galvanized steel, titanium (Ti), and zinc plated iron.
3 . The integral electronic stack of claim 1 , wherein the first electrically conductive adhesive layer forms a first resistive contact with the first electrically conductive layer, and the third electrically conductive adhesive layer forms a second resistive contact with the second board, and wherein the presence of the flexible metal film reduces a passive intermodulation signal generated in one or more of the first resistive contact and the second resistive contact by 5 dB to 80 dB inclusive.
4 . The integral electronic stack of claim 1 , wherein a passive intermodulation signal generated in the integral electronic stack is mainly caused by any one of the first board and the second board.
5 . The integral electronic stack of claim 1 , wherein bending a first point of each of the first board and the second board which are substantially rigid over a bend radius of between 1 mm and 10 mm deforms the rigid board at the first point irreversibly.
6 . An integral electronic stack comprising: a first electrically conductive adhesive layer, a second electrically conductive adhesive layer, a third electrically conductive adhesive layer; a flexible metal film which is disposed between the first electrically conductive adhesive layer and the second electrically conductive adhesive layer, and is bonded to the first electrically conductive adhesive layer and the second electrically conductive adhesive layer; and a second electrically conductive film which is disposed between the second electrically conductive adhesive layer and the third electrically conductive adhesive layer, and is bonded to the second electrically conductive adhesive layer and the third electrically conductive adhesive layer, wherein each of the first to third electrically conductive adhesive layers comprises a plurality of electrically conductive elements substantially distributed in an electrically insulative material, wherein, when a conductive circuit is provided by the steps of: providing a first gold microstrip and a second gold microstrip which are spaced apart from each other; arranging a same stainless steel plate on the first gold microstrip and the second gold microstrip; and arranging a multi-layer stack and a multi-layer stack which is substantially similar to the multi-layer stack between the stainless steel plate and the first gold microstrip, and the second gold microstrip, such that the first electrically conductive adhesive layers of the two multi-layer stacks are bonded to the same surface of the stainless steel plate, and the third electrically conductive adhesive layers of the two multi-layer stacks are bonded to the first gold microstrip and the second gold microstrip, respectively, if a first current signal and a second current signal which have strengths I1 and I2, respectively, which are substantially the same, and frequencies F1 and F2 which are different, are applied to the first gold microstrip, simultaneously, an intermodulation current signal that has a same frequency F3 as nF1+mF2 (m and n are positive or negative integers, not 0) is reflected by an electrical signal of strength I3, −150≤I3/I1≤−30 dB.
7 . The integral electronic stack of claim 6 , wherein the strengths I1 and I2 belong to 0% to 10% therebetween.
8 . The integral electronic stack of claim 6 , wherein the F1 and F2 are between about 0.4 GHz and 6 GHz.
9 . An integral electronic stack comprising a plurality of first electrically conductive flexible layer and a plurality of second electrically conductive flexible layer which alternate with each other, wherein the one or more first electrically conductive flexible layers are metal layers, and each of the plurality of second electrically conductive flexible layers is an adhesive layer that comprises a plurality of electrically conductive elements substantially distributed in an electrically insulative material, wherein an electrically grounded first circuit is formed by arranging an integral first multi-layer stack between a first board and a second board, the first board being substantially rigid such that the integral first multi-layer stack is bonded to the first board and the second board, respectively, the second board being electrically grounded and being substantially rigid, wherein an electrically grounded second circuit is formed by the steps of: providing an integral first partial multi-layer stack comprising only some of a plurality of layers of the integral first multi-layer stack, and an integral second partial multi-layer stack comprising some of the others of the plurality of layers of the integral first multi-layer stack: forming a first partial second circuit by bonding the integral first partial multi-layer stack to the first board, and forming a second partial second circuit by bonding the integral second partial multi-layer stack to the second board; and forming a second circuit by bonding the first partial second circuit and the second partial second circuit to each other, such that the integral second multi-layer stack is disposed between the first board and the second board, wherein the integral first multi-layer stack and the integral second multi-layer stack are substantially similar to each other, and have a same layer order from the first board to the second board, and wherein the second boards of the first circuit and the second circuit generate passive intermodulation signals I1 and I2, respectively, and the I1 is smaller than the I2 by between 5 dB and 80 dB.
10 . The integral electronic stack of claim 9 , wherein some of the other layers of the integral first multi-layer stack comprise any one of the plurality of first electrically conductive flexible layers, and any one of the plurality of second electrically conductive flexible layers.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a national stage filing under 35 U.S.C. 371 of PCT/IB2022/059512, filed Oct. 5, 2022, which claims the benefit of Korea Application No. 10-2021-0136941, filed Oct. 14, 2021, the disclosures of which are incorporated by reference in their entireties herein. TECHNICAL FIELD The disclosure relates to an integral electronic stack. BACKGROUND Recently, technology for mobile communication is being actively developed, and important factors for development of mobile communication are increasing a service capacity and enhancing communication quality. The increasing of the service capacity and the enhancement of the communication quality may be accompanied by a problem of inter-channel interference, and intermodulation distortion (IMD) may be an important factor of the interference problem. When two or more signal frequencies interfere with each other, an unexpected parasitic signal may be generated. For example, a phenomenon in which signal frequencies interfere with each other and a parasitic signal is generated in a passive element is referred to as passive intermodulation (PIM). Such passive intermodulation (PIM) occurs not only in a filter but also in most of passive elements having metal-to-metal contact, such as an antenna, a cable, a connector, a switch, or the like. In addition, the passive intermodulation (PIM) may occur due to loose mechanical bonding, oxidation on a bonding portion between ferrous-based metals, contamination on a surface of a conductor on RF welding, nonlinearity characteristics like hysteresis of a ferromagnetic material, or the like. SUMMARY Technical Problem The passive intermodulation (PIM) phenomenon mostly occurs in a process of communicating data at high speed in a communication device, etc. However, when the passive intermodulation occurs, it may influence interference between an uplink channel signal and a downlink channel signal, causing problems that a communication service radius is reduced and telephone connection efficiency is abruptly reduced. To this end, communication quality may deteriorate and inconvenience of a user may be caused. An embodiment of the disclosure has been developed based on the above-described background, and is to provide an electrically conductive circuit board in which passive intermodulation (PIM) caused by a plurality of signals is reduced. Technical Solution According to an aspect of the disclosure, there is provided an integral electronic stack for grounding an electrically conductive component in which passive intermodulation (PIM) is reduced, wherein the integral electronic stack includes a first integral stack and a second integral stack, the first integral stack being bonded to the second integral stack, wherein the first integral stack includes: a first board which is substantially rigid: a first electrically conductive layer which is disposed on at least part of a first main surface of the first board: a first electrically conductive adhesive layer and a second electrically conductive adhesive layer; and a first electrically conductive film which is disposed between the first electrically conductive adhesive layer and the second electrically conductive adhesive layer, and is bonded to the first electrically conductive adhesive layer and the second electrically conductive adhesive layer, respectively, the first electrically conductive adhesive layer and the second electrically conductive adhesive layer including a plurality of electrically conductive elements substantially distributed in an electrically insulative material, wherein the first electrically conductive adhesive layer bonds the first electrically conductive film to the one or more first electrically conductive layers, wherein the second integral stack includes: an electrically conductive second board which is substantially rigid: a third electrically conductive adhesive layer which includes a plurality of electrically conductive elements substantially distributed in an electrically insulative material; and a flexible metal film which is bonded to at least part of a first main surface of the second board through the third electrically conducive adhesive layer, wherein the first integral stack and the second integral stack are bonded to each other by the second electrically conductive adhesive layer which is bonded to the flexible metal film disposed opposite the third electrically conductive adhesive layer, and electrically connect the first electrically conductive layer to the second board. In addition, there is provided an integral electronic stack including: a first electrically conductive adhesive layer, a second electrically conductive adhesive layer, a third electrically conductive adhesive layer: a flexible metal film which is disposed between the first electrically conductive adhesive layer and the second electrically conductive adhesive layer, and is bonded to the first electrically conductive adhesive layer and