Electromagnetic interference (emi) shielding apparatus including electrically-conductive foam

Abstract

According to various aspects, exemplary embodiments are disclosed of shielding apparatus or assemblies including electrically-conductive foam. Also disclosed are exemplary embodiments of methods relating to making shielding apparatus or assemblies including electrically-conductive foam. Additionally, exemplary embodiments are disclosed of methods relating to providing shielding for one or more components on a substrate.

What is claimed is: 
     
         1 . An electromagnetic interference (EMI) shielding apparatus comprising electrically-conductive foam, wherein:
 the EMI shielding apparatus has a height of less than one millimeter;   the electrically-conductive foam has a flame rating of UL94 V-0; and   the electrically-conductive foam has no more than a maximum of 900 parts per million chlorine, no more than a maximum of 900 parts per million bromine, and no more than a maximum of 1,500 parts per million total halogens.   
     
     
         2 . The EMI shielding apparatus of  claim 1 , wherein:
 the electrically-conductive foam comprises polyurethane foam plated with metal; and/or   the electrically-conductive foam comprises foam plated with metal on a whole body of the foam; and/or   the electrically-conductive foam comprises internal surfaces which are electrically conductive due to at least one electrically conductive layer plated on the internal surfaces.   
     
     
         3 . The EMI shielding apparatus of  claim 1 , further comprising:
 an electrically-conductive adhesive layer along a bottom of the EMI shielding apparatus; and   a release liner over the electrically-conductive adhesive layer and configured to allow for a single removal of the release liner to expose the electrically-conductive adhesive layer for adhesively attaching the EMI shielding apparatus to a substrate.   
     
     
         4 . The EMI shielding apparatus of  claim 1 , further comprising a clear film adhesively attached along a top of the EMI shielding apparatus and operable as a stiffener for supporting the EMI shielding apparatus. 
     
     
         5 . The EMI shielding apparatus of  claim 4 , wherein:
 the clear film includes a tab for carrying the EMI shielding apparatus and for removing or peeling off the clear film from the EMI shielding apparatus; and/or   the clear film comprises a polyester film, a polyimide film, or a polyethylene naphthalate film.   
     
     
         6 . The EMI shielding apparatus of  claim 1 , wherein the electrically-conductive foam comprises multiple foam strips of the electrically-conductive foam including one foam strip shaped to define outermost sidewalls of the EMI shielding apparatus and at least one other foam strip defining at least one interior wall of the EMI shielding apparatus. 
     
     
         7 . The EMI shielding apparatus of  claim 1 , wherein the EMI shielding apparatus comprises a frame defined by the electrically-conductive foam, and a cover attachable to the frame. 
     
     
         8 . The EMI shielding apparatus of  claim 7 , wherein:
 the cover has no more than a maximum of 900 parts per million chlorine, no more than a maximum of 900 parts per million bromine, and no more than a maximum of 1,500 parts per million total halogens; and/or   the electrically-conductive foam has a compression set less than 25%; and/or   the cover has a surface resistivity of less than about 0.1 ohms/square.   
     
     
         9 . The EMI shielding apparatus of  claim 7 , wherein the frame comprises one or more outer sidewalls and one or more interior walls defined by the electrically-conductive foam such that the cover and the frame's sidewalls and interior walls cooperatively define a plurality of individual EMI shielding compartments, whereby when the frame is installed to a substrate, components of the substrate are positionable in different EMI shielding compartments and are provided with EMI shielding by virtue of the EMI shielding compartments inhibiting the ingress and/or egress of EMI into and/or out of each EMI shielding compartment. 
     
     
         10 . The EMI shielding apparatus of  claim 7 , wherein:
 the frame includes one or more sidewalls defined by the electrically-conductive foam such that the frame has an open top;   the cover is attachable to the frame for covering the open top of the frame; and   the one or more sidewalls of the frame are integrally defined by a single piece of the electrically-conductive foam such that the one or more sidewalls have a single-piece or unitary construction whereby the frame does not include any gaps between adjacent pairs of the one or more sidewalls and/or joints connecting separate sidewalls to each other.   
     
     
         11 . The EMI shielding apparatus of  claim 7 , wherein:
 the cover comprises an electrically-conductive fabric tape including Nickel/Copper polyester based fabric and an electrically-conductive pressure sensitive adhesive; and/or   the cover comprises at least one of an electrically-conductive fabric, a metalized clear film, or an electrically-conductive foam; and/or   the cover comprises an electrically-conductive layer, an adhesive layer, and a release paper layer.   
     
     
         12 . The EMI shielding apparatus of  claim 7 , wherein the cover comprises the same electrically-conductive foam as the frame. 
     
     
         13 . The EMI shielding apparatus of  claim 7 , wherein the cover comprises electrically-conductive foam that is different than the electrically-conductive foam of the frame. 
     
     
         14 . The EMI shielding apparatus of  claim 7 , further comprising a thermal interface material disposed along an inner surface of the cover, such that the thermal interface material is placed is contact with at least one heat source when the EMI shielding apparatus is installed to a printed circuit board over the at least one heat source, whereby a thermally-conductive heat path is defined from the at least one heat source through the thermal interface material to the cover. 
     
     
         15 . The EMI shielding apparatus of  claim 1 , wherein the EMI shielding apparatus consists only of the electrically-conductive foam. 
     
     
         16 . An electromagnetic interference (EMI) shielding apparatus comprising electrically-conductive foam, an electrically-conductive adhesive layer along a bottom of the EMI shielding apparatus, a release liner over the electrically-conductive adhesive layer and configured to allow for a single removal of the release liner to expose the electrically-conductive adhesive layer for adhesively attaching the EMI shielding apparatus to a substrate, and a clear film adhesively attached along a top of the EMI shielding apparatus and operable as a stiffener for supporting the EMI shielding apparatus. 
     
     
         17 . The EMI shielding apparatus of  claim 16 , wherein:
 the clear film includes a tab for carrying the EMI shielding apparatus and for removing or peeling off the clear film from the EMI shielding apparatus; and/or   the clear film comprises a polyester film, a polyimide film, or a polyethylene naphthalate film.   
     
     
         18 . The EMI shielding apparatus of  claim 16 , wherein:
 the EMI shielding apparatus has a height of less than one millimeter; and/or   the electrically-conductive foam has a flame rating of UL94 V-0; and/or   the electrically-conductive foam has no more than a maximum of 900 parts per million chlorine, no more than a maximum of 900 parts per million bromine, and no more than a maximum of 1,500 parts per million total halogens.   
     
     
         19 . The EMI shielding apparatus of  claim 16 , wherein:
 the electrically-conductive foam comprises polyurethane foam plated with metal; and/or   the electrically-conductive foam comprises foam plated with metal on a whole body of the foam; and/or   the electrically-conductive foam comprises internal surfaces which are electrically conductive due to at least one electrically conductive layer plated on the internal surfaces.   
     
     
         20 . The EMI shielding apparatus of  claim 16 , wherein:
 the EMI shielding apparatus comprises a frame defined by the electrically-conductive foam;   the electrically-conductive adhesive layer is along a bottom of the frame for adhesively attaching the frame to a substrate; and   the clear film is adhesively attached along a top of the frame and operable as a stiffener for supporting the frame.   
     
     
         21 . The EMI shielding apparatus of  claim 20 , further comprising a cover attachable to the frame, wherein:
 the cover has no more than a maximum of 900 parts per million chlorine, no more than a maximum of 900 parts per million bromine, and no more than a maximum of 1,500 parts per million total halogens; and/or   the cover comprises the same electrically-conductive foam as the frame.   
     
     
         22 . A method comprising providing an electromagnetic interference (EMI) shielding apparatus that comprises electrically-conductive foam, wherein:
 the EMI shielding apparatus has a height of less than one millimeter;   the electrically-conductive foam has a flame rating of UL94 V-0; and   the electrically-conductive foam has no more than a maximum of 900 parts per million chlorine, no more than a maximum of 900 parts per million bromine, and no more than a maximum of 1,500 parts per million total halogens.   
     
     
         23 . The method of  claim 22 , wherein the EMI shielding apparatus comprises one or more electrically conductive foam walls, and wherein providing an EMI shielding apparatus comprises:
 die-cutting the electrically-conductive foam walls from a single electrically-conductive foam sheet such that the electrically-conductive foam walls have a single-piece or unitary construction; or   cutting an electrically-conductive foam into one or more electrically-conductive foam strips, and bending at least one of the one or more electrically-conductive foam strips into the electrically-conductive foam walls.   
     
     
         24 . The method of  claim 23 , further comprising using vacuum nests or vacuum boards for attaching an electrically-conductive material to the electrically-conductive foam walls over an open top defined by the electrically-conductive foam walls.