US-12628678-B2 - Manufacturing of electronic components

US12628678B2US 12628678 B2US12628678 B2US 12628678B2US-12628678-B2

Abstract

The present disclosure concerns a method of manufacturing an electronic component and the obtained component, comprising a substrate, comprising the successive steps of: depositing a first layer of a first resin activated by abrasion to become electrically conductive, on a first surface of said substrate comprising at least one electric contact and, at least partially, on the lateral flanks of said substrate; partially abrading said first layer on the flanks of said substrate.

Inventors

Nicolas MODE
Ludovic Fallourd
Laurent Barreau

Assignees

STMICROELECTRONICS (TOURS) SAS

Dates

Publication Date: 20260512
Application Date: 20230113
Priority Date: 20220120

Claims (20)

1 . A method, comprising: forming a first recess extending into a first surface of a substrate, forming the first recess includes forming flanks of the substrate that are transverse to the first surface of the substrate and define the first recess; depositing a first layer of a first resin on the first surface of the substrate and at least partially on the flanks of the substrate, the first resin including a base material and an additive activatable material within the base material, the additive activatable material is activatable by abrasion to become electrically conductive; and forming a second recess in the first resin overlapping the first recess, forming the second recess includes forming flanks of the first resin that are transverse to the first surface of the substrate, activating the additive activatable material of the first resin within the second recess, and forming one or more conductive portions of the additive activatable material on and along the flanks of the first resin that define the second recess by partially abrading the first layer of the first resin on and along the flanks of the substrate.
2 . The method according to claim 1 , wherein forming the second recess in the first resin overlapping the first recess, activating the additive activatable material of the first resin within the second recess, and forming the one or more conductive portions of the additive activatable material on and along flanks of the second recess is performed by laser.
3 . The method according to claim 1 , wherein forming the second recess in the first resin overlapping the first recess, activating the additive activatable material of the first resin within the second recess, and forming the one or more conductive portions of the additive activatable material on and along flanks of the second recess is performed with a mechanical cutting device.
4 . The method according to claim 1 , wherein the first resin including the base material and the additive activatable material is non-conductive before activating the additive activatable material by abrasion.
5 . The method according to claim 1 , wherein: the base material is an electrically non-conductive material that disaggregates when forming the second recess, activating the additive activatable material, and forming one or more conductive portions of the additive activatable material by partially abrading the first layer on and along the flanks of the substrate; and the additive activatable material are metal particles covered with the electrically non-conductive material of the base material.
6 . The method according to claim 5 , wherein the base material is selected from a group comprising: epoxy-type resins and acrylic-type resins.
7 . The method according to claim 5 , wherein the metal particles are selected from a group comprising: copper, an alloy comprising copper, titanium, an alloy comprising titanium, nickel, an alloy comprising nickel, silver, and an alloy comprising silver.
8 . The method according to claim 1 , wherein forming the second recess in the first resin overlapping the first recess, activating the additive activatable material of the first resin within the second recess, and forming one or more conductive portions of the additive activatable material on and along flanks of the second recess is performed, the flanks of the second recess are spaced apart at a distance in a range from 5 to 20 μm from the flanks of the first recess of the substrate.
9 . The method according to claim 1 , further comprising forming of at least one electrically-conductive via through the first layer of the first resin and in contact with at least one electric contact at the first surface of the substrate.
10 . A method, comprising: forming a first recess with first flanks extending into a first surface of a substrate and terminating before reaching a second surface of the substrate opposite to the first surface; forming a doped resin within the first recess, the doped resin being doped with additive dopants that become electrical conductive when activated; forming a second recess with second flanks extending into the doped resin, terminating within the doped resin before reaching the substrate, extending into the first recess in the substrate, and spaced apart from the first flanks by utilizing a laser, forming the second recess by utilizing the laser includes simultaneously activating and exposing the additive dopants along and on the second flanks of the second recess; forming a first conductive layer on the additive dopants activated and exposed along and on the second flanks of the second recess; and forming a second conductive layer on the first conductive layer.
11 . The method of claim 10 , further comprising removing a portion of the substrate at the second surface of the substrate exposing an end of the doped resin within the first recess and forming a third surface of the substrate substantially coplanar with the end of the doped resin.
12 . The method of claim 11 , wherein forming a third recess extending from the second recess to the end of the doped resin.
13 . The method of claim 11 , further comprising forming a non-conductive layer on the third surface of the substrate and on the end of the doped resin.
14 . The method of claim 13 , wherein the non-conductive layer is made of a different material than the doped resin.
15 . The method of claim 13 , wherein the non-conductive layer is made of a first resin of a first layer.
16 . The method of claim 13 , further comprising forming a third recess extending from the second recess to a fourth surface of the non-conductive layer facing way from the substrate.
17 . The method of claim 10 , further comprising: forming an opening extending into the doped resin to the first surface of the substrate and to a contact at the first surface of the substrate; and forming a conductive via in the opening and coupled to the contact at the first surface of the substrate.
18 . The method of claim 17 , wherein the conductive via is coupled to the first and second conductive layers.
19 . A method, comprising: forming a first recess extending into a first surface of a substrate, forming the first recess includes forming a first end surface of the substrate and forming first flanks of the substrate, the first flanks are transverse to the first surface and the first end surface the first flanks extend from the first surface to the first end surface, and the first end surface of the substrate and the first flanks of the substrate define the first recess; depositing a first layer of a first resin on the first surface of the substrate and at least partially on the first flanks of the substrate, the first resin including a second surface, a base material, and an additive activatable material within the base material, the additive activatable material is activatable by abrasion to become electrically conductive; and performing an abrading process on the first resin, the abrading process includes: removing a portion of the first resin forming a second recess extending into the first resin and extending into the first recess, forming the second recess includes forming a second end surface of the first resin and forming second flanks of the first resin, the second flanks extend from the second surface to the second end surface, are transverse to the second surface and the second end surface, and are spaced inward from the first flanks, the second flanks of the first resin and the second end surface of the first resin define the second recess, and removing the portion of the first resin forming the second recess activates the additive activatable material of the first resin within the second recess forming one or more conductive portions of the additive activatable material on and along the second flanks and the second end surface of the second recess; and depositing a metal layer on the one or more conductive portions of the additive activatable material on and along the second flanks and the second end surface of the second recess.
20 . The method of claim 19 , wherein performing the abrading process on the first resin further includes: roughening a region adjacent to the second recess at and along the second surface of the first resin to activate the additive activatable material along the region adjacent to the second recess at and along the second surface of the first resin.

Description

BACKGROUND Technical Field The present disclosure concerns the manufacturing of electronic components, for example, the manufacturing of so-called surface mount components. Description of the Related Art In certain applications, there is a need for surface mount components where connection metallizations are intended to be soldered to an external device that extend all the way to the flanks of the components. In other words, these surface mount components may have wettable flanks. During the assembly of the component in its environment (for example, on a printed circuit board), the connection metallizations, or electric contacts, are welded or soldered to corresponding metal tracks or elements on the printed circuit side. A portion of the solder material then extends on the wettable flanks of the components, which enables implementation of a visual inspection of the quality of the connections. This need, for example, exists in the automobile field and the medical field and, more generally, in fields where the reliability of the electric connections is desired to be guaranteed, once the circuits have been assembled in their environment. It would be desirable to at least partially improve certain aspects of known methods of manufacturing electronic components or surface mount components with wettable flanks. BRIEF SUMMARY There is a need to improve known electronic devices and their manufacturing methods. At least one embodiment of the present disclosure at least partially overcomes the disadvantages of known wettable flank component manufacturing methods. At least another embodiment of the present disclosure provides a method of manufacturing an electronic component, comprising a substrate, comprising the successive steps of: depositing a first layer of a first resin activated by abrasion to become electrically conductive, over a first surface of said substrate comprising at least one electric contact and, at least partially, on lateral flanks of said substrate;partially abrading said first layer on the flanks of said substrate. According to an embodiment, the abrasion step is performed by laser, which may be referred to as a laser ablation step. For example, when the laser is exposed to the first resin, the laser may activate a dopant within the first resin such that the dopant becomes conductive when exposed to the laser. The dopant may be referred to as an additive dopant, an activatable dopant, or some similar or like reference to the dopant that becomes conductive when exposed to the laser. According to an embodiment, the abrasion step is performed with a mechanical cutting device. According to an embodiment, if the first resin has not been activated by abrasion, it is electrically insulating. For example, the first resin may be doped with a dopant that is initially non-conductive until the dopant is activated by the abrasion step, which may be performed by various types of removal tools (e.g., mechanical cutting device, laser, etc.). According to an embodiment, the first resin comprises a basic material and metal particles covered with an electrically-insulating protective layer. For example, the metal particles, which may be referred to as dopants, of the first resin are present within the basic material of the first resin. According to an embodiment, the basic material is selected from the group comprising: epoxy-type resins and acrylic-type resins. According to an embodiment, the metal particles are made of a material selected from the group comprising: copper, an alloy comprising copper, titanium, an alloy comprising titanium, nickel, an alloy comprising nickel, silver, and an alloy comprising silver. These metal particles may be referred to as dopants. According to an embodiment, during the abrasion step, a cavity is formed. According to an embodiment, the abrasion step is performed at a distance in the range from 5 to 20 μm from the flanks of the component. According to an embodiment, the method further comprises a step of forming of at least one electrically-conductive via, in contact with said at least one electric contact, through said first layer. An embodiment provides an electronic component comprising a chip protected by a package having at least one electric contact extending on a portion of a first surface of said package and a portion of a flank of said package formed thereon, the first surface being, further, a layer of a first resin activated by abrasion to become electrically conductive. According to an embodiment, the component is obtained according to the described method. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS The foregoing features and advantages, as well as others, will be described in detail in the following description of specific embodiments given by way of illustration and not limitation with reference to the accompanying drawings, in which: FIG. 1 shows a cross-section view of an embodiment of an electronic component with wettable flanks of the present discl