PRIORITY CLAIM

This application claims the priority benefit of French Application for Patent No. 2001103, filed on Feb. 4, 2020, the content of which is hereby incorporated by reference in its entirety to the maximum extent allowable by law.

TECHNICAL FIELD

Embodiments and applications relate to microelectronics and, in particular, to the field of electronics units and particularly that of electronics units comprising a non-conductive encapsulation cover mounted on a support substrate and incorporating an antenna.

BACKGROUND

A support substrate is typically used for supporting and connecting one or more electronic integrated circuit chips and possibly components of the surface mounted device (SMD) type. A non-conductive encapsulation cover is used, in particular, for enclosing the electronic integrated circuit chip and other possible components and thus arranging a device or unit which is able to be manipulated and is protected from external conditions.

The mounting of the non-conductive encapsulation cover to the support substrate conventionally comprises arranging a strip of adhesive, for example on the periphery of the bearing surface of the support substrate, and joining together the cover and the substrate by contacting the strip of adhesive.

The incorporation of an antenna into the unit is increasingly demanded by users, particularly for future radiofrequency applications, for example 5G but by no means limited to 5G applications, that require a high degree of integration.

Current solutions provide the formation of the antenna on the bearing surface of the support substrate by depositing a specific metal or even by soldering the cover to the substrate.

Such solutions lead to an increase in the size of the units and/or to an increase of the manufacturing costs.

It is thus necessary to propose a different solution for incorporating an antenna into a unit which does not have a negative impact on the bulkiness of the surface and/or on the manufacturing costs.

SUMMARY

According to one embodiment, it is proposed to use U-shaped metal wires, which makes it possible to connect a metallic pattern arranged on the internal face of the cover to the bearing surface of the substrate. This makes it possible to either: form an antenna and connect it in a simple manner to a component located on the bearing surface of the substrate; or form an electromagnetic protective shield that can thus be arranged as close to the component as possible. A plurality of U-shaped metal wires can be arranged, for example, around the electronic integrated circuit chip so as to form a network that is as dense as possible in order to ensure good electromagnetic protection.

Furthermore, the formation of said U-shaped metal wires can be carried out advantageously in the same way as the formation of wire bonding between the electronic integrated circuit chip and the substrate, which does not require a different manufacturing process.

According to one aspect, a unit or device is proposed, comprising: a support substrate having a bearing surface; a non-conductive encapsulation cover mounted on said bearing surface of the support substrate and delimiting with the support substrate an internal housing of the unit; at least one electronic integrated circuit chip located in the internal housing and supported by said bearing surface; a metallic pattern arranged at least on an internal wall of the non-conductive encapsulation cover located opposite the bearing surface; and a plurality of U-shaped metal wires extending into said internal housing, to the side of said at least one electronic integrated circuit chip, being fixed on the one hand to the metallic pattern and on the other hand to the bearing surface.

The expression “U-shaped” should be interpreted very broadly to include any curved structure with two branches, even if this structure is not exactly U-shaped.

According to one embodiment, the bend of each U-shaped metal wire can be fixed onto the metallic pattern and the two legs of each U-shaped metal wire can be fixed onto the bearing surface.

In one variant, it is possible to fix the two legs of the U-shaped metal wire onto the metallic pattern, the bend of the U-shaped metal wire being fixed onto the bearing surface.

The use of U-shaped metal wires is compatible with all methods of mounting the electronic integrated circuit chip onto the bearing surface.

Thus, it is of course possible to mount the electronic integrated circuit chip by means of connecting balls soldered onto the bearing surface and coated with an underfill material.

That being said, it is also possible to use another conventional mounting method, which is known per se, of the electronic integrated circuit chip onto the bearing surface of the substrate comprising soldered wire bonding between the metallic pads of said at least one electronic integrated circuit chip and metal areas located on the bearing surface of the support substrate.

In this case, the U-shaped metal wires are structurally identical to these bonding wires which are obtained advantageously by an identical method.

According to one embodiment, the unit comprises an antenna including the metallic pattern and a connector, making it possible to connect said antenna to at least one component located on said bearing surface, said connector including at least two U-shaped metal wires.

These two U-shaped metal wires thus make it possible to connect the two terminals of the antenna to a component or to a circuit located on the bearing surface of the unit, for example a circuit for adapting the impedance.

According to another possible embodiment, the unit can include a plurality of U-shaped metal wires arranged at the periphery of the internal housing and surrounding said at least one electronic integrated circuit chip.

The unit can thus include an electromagnetic protective shield including said metallic pattern and said U-shaped metal wires arranged at the periphery of the internal housing.

According to another aspect, a method for forming a unit comprises: providing a support substrate having a bearing surface; mounting at least one electronic integrated circuit chip on the bearing surface (the term “mounting” should be interpreted very broadly here, including not only fixing the electronic integrated circuit chip onto the bearing surface but also the formation of its connector, for example by means of connecting balls coated with an underfill material or even the formation of wire bonding and soldering thereof); fixing a plurality of U-shaped metal wires onto the bearing surface, projecting to the side of said at least one electronic integrated circuit chip; providing a non-conductive encapsulation cover; forming a metallic pattern at least on the internal wall of the cover designed to be opposite the bearing surface after mounting the cover on the bearing surface; locally forming soldering means, for example soft pads of soldering paste, onto said metallic pattern; mounting the non-conductive encapsulation cover onto said bearing surface of the support substrate such that the projecting ends of the U-shaped metal wires come into contact with the localized soldering means; and raising the temperature of the unit, for example by heating in an oven, so as to solder the projecting ends of the U-shaped metal wires onto the metallic pattern.

According to another aspect, a method for forming a unit comprises: providing a support substrate having a bearing surface; mounting at least one electronic integrated circuit chip on the bearing surface; locally forming soldering means, for example soft pads of soldering paste, on said bearing surface, to the side of said at least one electronic integrated circuit chip; providing a non-conductive encapsulation cover; forming a metallic pattern at least on the internal wall of the cover designed to be opposite the bearing surface after mounting the cover on the bearing surface; fixing a plurality of projecting U-shaped metal wires onto the metallic pattern designed to extend to the side of said at least one electronic integrated circuit chip after mounting the cover on the bearing surface; mounting the non-conductive encapsulation cover onto said bearing surface of the support substrate in such a manner that the projecting ends of the U-shaped metal wires come into contact with localized soldering means; and raising the temperature of the unit so as to solder said projecting ends of the U-shaped metal wires onto said bearing surface.

In one or other of these other aspects, the projecting ends of the U-shaped metal wires are advantageously the bends of the U-shaped metal wires.

