Electronic circuit assemblies, methods of manufacturing the same, and modules
An electronic circuit assembly comprises: a first electronic circuit module; a second electronic circuit module; and a quantity of anisotropic conductive adhesive, ACA, comprising a plurality of electrically conductive particles and an electrically non-conductive adhesive, arranged to bond the first electronic circuit module to the second electronic circuit module. The first electronic circuit module comprises a first surface and a first pair of electrical contacts each provided on said first surface, the second electronic circuit module comprises a second surface and a second pair of electrical contacts each provided on said second surface, said first surface is arranged to face said second surface, said first pair of electrical contacts is aligned with said second pair of electrical contacts such that a first electrical contact of the first pair opposes a first electrical contact of the second pair and a second electrical contact of the first pair opposes a second electrical contact of the second pair, said quantity of ACA occupies a volume between the first and second surfaces, and conductive particles of the ACA provide a first electrical connection between the first electrical contacts of the first and second pairs, and a second electrical connection between the second electrical contacts of the first and second pairs. The first electronic circuit module further comprises at least one member provided on and protruding from said first surface and arranged between the first pair of electrical contacts, and at least one channel provided through a said member or defined between a plurality of said members, each said channel providing a flow channel, in a direction parallel to the first surface, for at least said non-conductive adhesive during manufacture of the assembly.
1 . An electronic circuit module comprising a first surface and a first electrical contact provided on said first surface, for bonding to a second electronic circuit module comprising a second surface and a second electrical contact provided on said second surface to form an electronic circuit assembly by providing a quantity of anisotropic conductive adhesive, ACA, comprising a plurality of electrically conductive particles and an electrically non-conductive adhesive, between the first and second surfaces and urging said surfaces towards each other, with said contacts aligned such that conductive particles form an electrical connection between the first and second contacts,
the electronic circuit module further comprising at least one perimeter member provided on and protruding from said first surface and spaced from the first electrical contact and arranged to provide a raised perimeter barrier around the first electrical contact, said raised perimeter barrier comprising at least one channel provided through a said perimeter member, each said channel located between respective ends of the perimeter member and providing a flow channel arranged to permit, during manufacture of the assembly, a portion of the non-conductive adhesive of a quantity of ACA deposited inside the raised perimeter barrier to flow out of the raised perimeter barrier to an area outside the raised perimeter barrier, and arranged to inhibit, during manufacture of the assembly, flow of the conductive particles of said quantity of ACA deposited inside the raised perimeter barrier,
wherein the at least one perimeter member comprises a first perimeter member having a surface in which a plurality of surface channels are provided, each surface channel having a depth smaller than a thickness of the first perimeter member and being arranged to permit flow of the non-conductive adhesive through it, during manufacture of the assembly, from one side of the first perimeter member to an opposite side of the first perimeter member.
2 . The module in accordance with claim 1 , wherein each said channel has a width not exceeding X, such that each channel is arranged to inhibit or prevent flow through it, during manufacture of the assembly, of conductive particles of said quantity of ACA having a minimum dimension greater than X out of the raised perimeter barrier.
3 . The module in accordance with claim 1 , wherein the first electrical contact protrudes from said first surface.
4 . The module in accordance with claim 3 , wherein the first electrical contact and each perimeter member protrudes from the first surface by the same distance.
5 . The module in accordance with claim 1 , wherein at least one groove or surface channel is provided in a surface of the first electrical contact.
6 . The module in accordance with claim 1 , wherein a surface of the first electrical contact is provided with at least one groove, surface channel, depression, hollow, or window down to the first surface, for trapping conductive particles of the ACA.
7 . The module in accordance with claim 1 , wherein the first electrical contact comprises a plurality of first electrical contact members, each arranged inside the raised perimeter barrier.
8 . The module in accordance with claim 7 , wherein the plurality of first electrical contact members are arranged in a plurality of rows and a plurality of columns.
9 . The module in accordance with claim 1 , wherein the first perimeter member encloses the first contact.
10 . The module in accordance with claim 1 , further comprising a further electrical contact provided on said first surface, wherein said at least one channel comprises at least one channel arranged to permit, during manufacture of the assembly, a portion of the non-conductive adhesive of a quantity of ACA deposited inside the raised perimeter barrier to flow out of the raised perimeter barrier in a direction towards the further electrical contact.
11 . The module in accordance with claim 10 , further comprising at least one further perimeter member provided on and protruding from said first surface and spaced from the further electrical contact and arranged to provide a second raised perimeter barrier around the further electrical contact, said second raised perimeter barrier raised from the first surface, said second raised perimeter barrier comprising at least one further channel provided through a said further perimeter member or defined between a plurality of said further perimeter members, each said further channel providing a flow channel arranged to permit, during manufacture of the assembly, a portion of the non-conductive adhesive of a quantity of ACA deposited inside the second raised perimeter barrier to flow out of the second raised perimeter barrier.
12 . The module in accordance with claim 10 , further comprising at least one additional member, each additional member protruding from the first surface and being provided on said first surface in a region of the first surface between the first and further contacts.
13 . The module in accordance with claim 12 , further comprising at least one additional channel provided through a said additional member or defined between a plurality of said additional members, each said additional channel providing a flow channel arranged to permit, during manufacture of the assembly, non-conductive adhesive to flow through it.
14 . An electronic circuit assembly comprising a first electronic circuit module in accordance with claim 1 , a second electronic circuit module comprising a second surface and a second electrical contact provided on said second surface, and a quantity of ACA comprising a plurality of electrically conductive particles and an electrically non-conductive adhesive, occupying a volume between the first and second surfaces, the first surface facing the second surface and the first contact being aligned with the second contact such that conductive particles of the ACA form an electrical connection between the first and second contacts.
15 . The assembly in accordance with claim 14 , wherein a numerical density of said electrically conductive particles is greater inside the raised perimeter barrier than in an area of the first surface outside the raised perimeter barrier.
16 . An electronic circuit module comprising a first surface and a first electrical contact provided on said first surface, for bonding to a second electronic circuit module comprising a second surface and a second electrical contact provided on said second surface to form an electronic circuit assembly by providing a quantity of anisotropic conductive adhesive, ACA, comprising a plurality of electrically conductive particles and an electrically non-conductive adhesive, between the first and second surfaces and urging said surfaces towards each other, with said contacts aligned such that conductive particles form an electrical connection between the first and second contacts,
the electronic circuit module further comprising at least one perimeter member provided on and protruding from said first surface and spaced from the first electrical contact and arranged to provide a raised perimeter barrier around the first electrical contact, said raised perimeter barrier comprising at least one channel provided through a said perimeter member, each said channel located between respective ends of the perimeter member and providing a flow channel arranged to permit, during manufacture of the assembly, a portion of the non-conductive adhesive of a quantity of ACA deposited inside the raised perimeter barrier to flow out of the raised perimeter barrier to an area outside the raised perimeter barrier, and arranged to inhibit, during manufacture of the assembly, flow of the conductive particles of said quantity of ACA deposited inside the raised perimeter barrier,
the module further comprising:
a further electrical contact provided on said first surface, wherein said at least one channel comprises at least one channel arranged to permit, during manufacture of the assembly, a portion of the non-conductive adhesive of a quantity of ACA deposited inside the raised perimeter barrier to flow out of the raised perimeter barrier in a direction towards the further electrical contact; and
at least one further perimeter member provided on and protruding from said first surface and spaced from the further electrical contact and arranged to provide a second raised perimeter barrier around the further electrical contact, said second raised perimeter barrier raised from the first surface, said second raised perimeter barrier comprising at least one further channel provided through a said further perimeter member or defined between a plurality of said further perimeter members, each said further channel providing a flow channel arranged to permit, during manufacture of the assembly, a portion of the non-conductive adhesive of a quantity of ACA deposited inside the second raised perimeter barrier to flow out of the second raised perimeter barrier.