Method of manufacturing electronic component

Abstract

The invention relates to a method of manufacturing an electronic component. A hydrophobic electronic component is made using a process step of depositing a hydrophobic coating on an electronic component. The electronic component includes a substrate, a chip positioned on a first side of the substrate, an electrical connection terminal positioned on a second side of the substrate, an electrical track passing through the substrate, and a resin or cover covering the first side of the substrate and the chip.

Description

[0001] Priority claim

[0002] This application claims the benefit of priority from French patent application No. 2402204, filed on March 5, 2024, the contents of which are incorporated herein by reference in their entirety to the maximum extent permitted by law. Technical Field

[0003] The present disclosure relates to the manufacture of electronic components, and more particularly, to the manufacture of packaged type electronic components. Background Art

[0004] Packaged electronic components typically include one or more integrated circuit (IC) chips mounted on the front side of a substrate made of a non-conductive material. The chip(s) are protected from the outside environment by a resin layer covering the front side of the substrate. Electrical contact terminals are located on the back side of the substrate. Electrical tracks pass through the substrate and couple the chip(s) to the electrical terminals.

[0005] In order to be used in humid environments, these electronic components must have high water and humidity resistance.

[0006] To achieve this goal, one solution is to use a ceramic substrate. However, using this substrate makes it impossible to miniaturize the components. Another solution would be to add an additional environmentally sealed package, but this would increase the size of the electronic components and make their installation in the final product more difficult.

[0007] There is a need to at least partially improve certain aspects of known electronic component manufacturing methods in order to obtain waterproof and moisture-proof electronic components that can be miniaturized. Summary of the Invention

[0008] An embodiment presents a method for manufacturing a hydrophobic electronic component, including the step of depositing a hydrophobic coating on the electronic component, the electronic component including a substrate, a chip positioned on a first side of the substrate, electrical connection terminals positioned on a second side of the substrate and electrically coupled to the chip by means of electrical tracks passing through the substrate, and a resin or cover covering the first side of the substrate and the chip.

[0009] According to a specific embodiment, the method includes the steps of: providing an element including a plurality of electronic components; separating the electronic components; bonding electrical connection pads to electrical connection terminals; and depositing a hydrophobic coating to completely cover the electronic components.

[0010] According to a particular embodiment, the method further comprises a subsequent step during which the hydrophobic coating deposited on the electrical connection pad is removed.

[0011] According to a specific embodiment, the electrical connection pads are protected during deposition of the hydrophobic coating.

[0012] According to a specific embodiment, the method includes the following steps: providing an element including a plurality of electronic components; depositing a hydrophobic coating to cover the resin or cover and the second side of the substrate; performing a step of removing the hydrophobic coating deposited on the electrical terminals; optionally, bonding electrical connection pads to the electrical terminals; and separating the electronic components.

[0013] According to a specific embodiment, the method comprises the following steps: providing an element comprising a plurality of electronic components; separating the electronic components; depositing a hydrophobic coating to completely cover the electronic components; performing a step of removing the hydrophobic coating deposited on the electrical terminals; and optionally, bonding electrical connection pads to the electrical terminals.

[0014] According to a particular embodiment, the hydrophobic coating is a composite material comprising a polymer material in which a filler is dispersed, preferably made of ceramic or graphene, and even more preferably made of alumina or silica.

[0015] According to a specific embodiment, the substrate is made of a resin, preferably an epoxy resin, or a composite material comprising a filler, such as glass fibers, dispersed in a resin, preferably an epoxy resin.

[0016] An embodiment also relates to an electronic component comprising a substrate, a chip positioned on a first side of the substrate, electrical connection terminals positioned on a second side of the substrate and electrically coupled to the chip by means of electrical tracks passing through the substrate, a resin or a cover covering the first side of the substrate and the chip, and a hydrophobic coating covering at least the resin or the cover and the second side of the substrate between the electrical connection terminals.

[0017] According to a particular embodiment, the hydrophobic coating is a composite material comprising a polymer material in which a filler is dispersed, preferably made of ceramic or graphene, and even more preferably made of alumina or silica.

[0018] According to a specific embodiment, the substrate is made of a resin, preferably an epoxy resin, or a composite material comprising a filler, such as glass fibers, dispersed in a resin, preferably an epoxy resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The foregoing features and advantages, as well as other features and advantages, will be described in detail in the remainder of the disclosure of specific embodiments given by way of illustration and not limitation, with reference to the accompanying drawings, in which:

[0020] Figures 1A to 1E There are shown cross-sectional views illustrating steps of a method of manufacturing an electronic component;

[0021] Figures 2A to 2E shows cross-sectional views illustrating steps of a method of manufacturing an electronic component; and

[0022] Figures 3A to 3E Cross-sectional views illustrating steps of a method of manufacturing an electronic component are shown. DETAILED DESCRIPTION

[0023] Similar features are denoted by similar reference numerals in the various drawings. In particular, common structural and / or functional features in various embodiments may have the same reference numerals and may have identical structures, dimensions, and material properties.

[0024] For clarity, only those steps and elements that are useful for understanding the embodiments are shown and described in detail.

[0025] Unless otherwise stated, when two elements are referred to as being connected together, this means a direct connection without any intervening elements other than conductors, and when two elements are referred to as being coupled together, this means the two elements may be connected or they may be coupled via one or more other elements.

[0026] In the following description, when reference is made to absolute position qualifiers (such as "front", "back", "top", "bottom", "left", "right", etc.) or relative position qualifiers (such as "top", "bottom", "up", "down", etc.) or orientation qualifiers (such as "horizontal", "vertical", etc.), unless otherwise specified, they refer to the orientation of the drawing.

[0027] Unless otherwise indicated, the expressions "about," "approximately," "substantially," and "around" mean plus or minus 10%, preferably plus or minus 5%.

[0028] like Figures 1A to 1E 、 Figures 2A to 2E and Figures 3A to 3E As shown in FIG, a method for manufacturing a hydrophobic electronic component 100 includes at least one step during which a hydrophobic coating 170 is formed on the electronic component 100. The electronic component 100 includes a substrate 110; an integrated circuit (IC) chip 120 positioned on a first side 111 of the substrate 110, wherein electrical connection terminals 140 are positioned on a second side 112 of the substrate 110 and electrically coupled to the chip 120 by means of electrical tracks 130 extending through the substrate 110; and a protective element 150, typically a resin or a cover, covering the first side 111 of the substrate 110 and the chip 120. The chip is, for example, a BGA-type chip mounted to the substrate 110 in a so-called "flip-chip" orientation, and the electrical tracks 130 couple the lower surface of the chip 120 to the terminals 140.

[0029] The hydrophobic coating 170 protects the electronic component 100 from the external environment, particularly from water and moisture in the external environment.

[0030] The resulting water and moisture resistance is comparable to that of ceramic substrates. This increases the component's service life and corrosion resistance.

[0031] For example, water resistance and moisture resistance can be evaluated according to standard J-STD-033D.

[0032] More particularly, the method advantageously comprises at least the following steps:

[0033] a) providing an element 1000 comprising a plurality of electronic components 100 having a common substrate 110 , each electronic component comprising one or more chips 120 arranged on a first side 111 of the substrate 110 , electrical connection terminals 140 arranged on a second side 112 of the substrate 110 , and electrical tracks 130 coupling the chip(s) 120 to the electrical connection terminals 140 ;

[0034] b) cutting the substrate 110 between the chips 120 to form individual electronic components 100; and

[0035] c) forming a hydrophobic coating 170 .

[0036] The steps may be performed in a different order: a), b) and c) or a), c) and b). In other words, the coating 170 may be applied before singulation of the component 100 or after singulation.

[0037] The following describes in more detail a component of the “flip chip” type, i.e. a component with a BGA (ball grid array) component having connection pads 160 (“bumps”) located underneath the chip, but it can also be a component of the “wire bonding” type, i.e. a component with LGA (land grid array) electronic components, to which the connection is achieved using wires made, for example, of gold, silver or copper.

[0038] according to Figures 1A to 1E In a first alternative embodiment shown in FIG, the method comprises the following steps: a) providing an element 1000 ( Figure 1A ) d) bonding the electrical connection pad 160 to the electrical connection terminal 140 ( Figure 1B ); b) cutting the substrate 110 to separate the individual electronic components 100 ( Figure 1C ); and c) forming a hydrophobic coating 170 ( Figure 1D ).

[0039] During step c), the coating covers (preferably completely covers) the electronic component 100. The coating can be formed in one or more steps.

[0040] According to this first alternative embodiment, the method may further comprise a step e) during which the hydrophobic coating 170 ( Figure 1E ).

[0041] This removal step is performed, for example, by chemical etching or by mechanical action, in particular by means of polishing.

[0042] Alternatively, and still according to this first embodiment, the method may comprise a step during which the electrical connection pads 160 are protected by a protective element during the formation of the hydrophobic coating 170 .

[0043] After the hydrophobic coating 170 is deposited, the protective element is removed. For example, if the component 100 is positioned on an adhesive support by gluing the connection pads 160 to this support during the deposition of the hydrophobic coating 170, the connection pads 160 will not be completely covered by the coating 170. The adhesive support will be chosen to be soft enough to allow the ball to partially sink into it. This embodiment is also compatible with LGA (Land Grid Array) type electronic components.

[0044] According to the second embodiment, Figures 2A to 2E As shown in FIG, the method comprises the following steps: a) providing an element 1000 ( Figure 2A c) depositing a hydrophobic coating 170 on the resin and on the second side 112 of the substrate 110 ( Figure 2B ); e) performing a step of removing the hydrophobic coating 170 deposited on the electrical terminal 140, for example by etching ( Figure 2C ) d) preferably bonding the electrical connection pad 160 to the electrical terminal 140 ( Figure 2D ); and b) separating the individual electronic components 100 ( Figure 2E ).

[0045] According to the third embodiment, Figures 3A to 3E As shown in FIG, the method comprises the following steps: a) providing an element 1000 ( Figure 3A ); b) separating the individual electronic components 100 ( Figure 3B ); c) depositing a hydrophobic coating 170 to completely cover the electronic components ( Figure 3C ); e) etching the hydrophobic coating 170 so that the electrical connection terminal 140 can be touched ( Figure 3D ); and d) optionally, the electrical connection pad 160 is joined to the electrical terminal 140 ( Figure 3E ).

[0046] According to this third alternative embodiment, it is possible to manufacture electronic components of the BGA (Ball Grid Array) type or the LGA (Land Grid Array) type, depending on whether step d) is completed or not.

[0047] The steps of these different alternative embodiments will be described in further detail.

[0048] The component 1000 provided in step a) includes a plurality of electronic components 100, each of which includes at least one chip 120, a substrate 110, and a protection element 150. The substrate 110 is common to all electronic components 100. The component 1000 preferably has a matrix format ('BGA matrix' or 'LGA matrix').

[0049] Chip 120 may include one or more discrete components. The discrete component(s) may be selected, for example, from transistors, diodes, thyristors, triacs, filters, and the like. Chip 120 may include one or more electronic circuits. Chip 120 enables various electronic functions. Capacitors and inductors may be mentioned as examples.

[0050] The electronic component 100 is a so-called integrated component.

[0051] At step a), the fabrication of the discrete component(s) and / or integrated circuit(s) forming the electronic component 100 is complete. The component 100 has not yet been singulated.

[0052] The substrate 110 includes a first side 111 (an upper surface or front surface) and a second side 112 (a lower surface or rear surface).

[0053] The chip 120 is bonded to the first side 111 of the substrate 110. In the figures, a single chip 120 is shown for each component 100, but the electronic component may include a plurality of chips 120.

[0054] The substrate 110 comprises an electrically insulating material in which the electrical tracks 130 are formed. The electrically insulating material may be a resin, a polymer or a composite material comprising a resin or polymer in which a non-conductive filler such as glass fiber is dispersed. The resin is preferably an epoxy type resin.

[0055] The electrical tracks 130 of the substrate 110 extend from the first side 111 of the substrate 110 to the second side 112 of the substrate 110 to allow the chip 120 to be connected to external devices. The electrical tracks 120 completely pass through the substrate 110.

[0056] The rail 130 is made of copper, for example.

[0057] Electrical connection terminals 140 (also called electrical connection pads or electrical contacts) are positioned on the second side 112 of the substrate 110. They are connected to the electrical tracks 130 of the substrate 110.

[0058] They are made of a conductive material specifically adapted to allow bonding of the connection pads 160. The electrical connection terminals 140 comprise at least one of the following elements: gold, titanium, nickel, copper, silver, tin or tungsten. Preferably, they comprise gold or copper. They may be plated.

[0059] Preferably, the substrate 110 and the electrical tracks 130 form a printed circuit board (PCB).

[0060] The chip 120 is protected by a protection element 150. The protection element 150 covers the first side 111 of the substrate 110 and the chip 120. More specifically, the upper surface and the flanks of the chip 120 are protected by this element 150. The lower surface of the chip 120 faces the substrate 110.

[0061] The protection element 150 may be a layer of insulating material 150 , preferably a resin layer.

[0062] For example, the resin comprises at least one matrix material to which electrically insulating particles are added. The matrix material is, for example, selected from the group consisting of epoxy resins, phenolic resins, and acrylic resins. Preferably, it is an epoxy resin. The particles are, for example, oxide particles, and in particular, aluminum oxide particles or silicon dioxide particles.

[0063] The resin can be cured under ultraviolet (UV) radiation or by thermal activation. Annealing can also be performed.

[0064] The resin may be deposited by injection ("molding").

[0065] For example, resin is molded onto the substrate 110 and the chip 120 .

[0066] Alternatively, the protection element 150 is a cover 150 , made of metal or plastic, in contact with the chip 120 or not.

[0067] During step b), the individual electronic components 100 are separated from one another. This step is performed by cutting the substrate 110 and the resin layer 150 between the chips 120.

[0068] This singulation step is performed by means of a cutting device. The cutting device is, for example, a mechanical cutting tool, such as a saw, or a laser or plasma etching tool. According to another embodiment, the cutting device is a laser.

[0069] During step c), a hydrophobic coating 170 is formed.

[0070] The hydrophobic coating 170 is preferably a composite material comprising a polymer having a filler dispersed therein. The filler is preferably non-conductive.

[0071] The filler can be made of ceramic or carbon materials such as graphene.

[0072] Oxide fillers are particularly selected, preferably aluminum oxide, yttria, zirconium oxide or silicon dioxide fillers.

[0073] Alternatively, metal-organic complexes or complexes of transition metals may be used.

[0074] The hydrophobic coating 170 has a thickness in the range of 2 nm to 20 μm.

[0075] The coating can be deposited in the gas phase or in the liquid phase. The liquid phase may contain an organic solvent.

[0076] Preferably, before forming the coating 170 , a drying (“baking”) step is performed, for example at a temperature ranging from 80 to 140° C., preferably from 90 to 130° C. This step makes it possible to remove all traces of moisture before forming the hydrophobic coating 170 .

[0077] When coating 170 is deposited on element 1000 ( Figure 2B ), during step b), the flanks of the electronic component 100 are not covered by the hydrophobic coating 170. During this step, only the first side (front side) and the second side (back side) of the component may be covered by the hydrophobic coating 170.

[0078] When the hydrophobic coating 170 is deposited on the singulated electronic components 100 ( Figure 1D and Figure 3C ), which can be deposited on the first side, second side, and flanks of each electronic component 100. This type of application results in improved moisture resistance. The hydrophobic coating can be formed in multiple steps, for example by coating the front side and then the back side, or vice versa. The flanks can be coated at the same time as the front side, or at the same time as the back side.

[0079] During step d), the electrical connection pads 160 are bonded to the electrical connection terminals 140 .

[0080] The connection pads 160 are, for example, bumps having a diameter in the range of 50 μm to 900 μm (and preferably in the range of 150 μm to 800 μm).

[0081] The electrical connection pads are made of, for example, a tin alloy, preferably a tin-silver-copper alloy (SnAgCu or SAC).

[0082] This step can be performed by welding.

[0083] The solder material may be pre-deposited on the connection terminals 140. The solder material may be deposited using a printing technique, preferably screen printing. Any additive deposition technique may be used. The solder material may be made of Sn or a tin alloy (such as SnAgCu or SnAg) or another alloy with a higher melting point.

[0084] During step e), the hydrophobic coating 170 is partially removed to expose the electrical connection pads 160 and / or the electrical connection terminals 170 .

[0085] This step can be performed by chemical etching, with the aid of a masking step.

[0086] A mechanical removal step may also be performed if it is desired to remove the portion of the coating 170 located on the pad 160. This embodiment is advantageous in case of large dimensions of the pad 160, typically dimensions greater than 350 μm in diameter.

[0087] At the end of the method, each electronic component 100 includes a substrate 110, one or more chips 120 arranged on a first side 111 of the substrate, a resin 150 covering the substrate 110 and the chip(s) 120, and electrical connection terminals 140 arranged on a second side 112 of the substrate 110. Electrical tracks 130 electrically couple the chips 120 to the electrical connection terminals 140. A hydrophobic coating 170 covers at least the second side 112 of the substrate 110 and the protective element 150 between the electrical connection terminals 140. The hydrophobic coating 170 may also cover the side surfaces of the electronic component 100.

[0088] The connection pads 160 may be bonded to the electrical connection terminals 140 .

[0089] Such a component 100 may be bonded to an external device, such as a printed circuit board or other component.

[0090] These electronic components 100 may be applied in many industrial fields and in particular in the automotive, aerospace or naval fields (particularly for use on board ships / vessels) or for devices intended to be placed in wet rooms (such as bathrooms), underground locations, outdoors.

[0091] Those skilled in the art will appreciate that certain features of these various embodiments and variations may be combined, and that other variations will occur to those skilled in the art.

[0092] Finally, based on the functional indications given above, the actual implementation of the described embodiments and variants is within the capabilities of a person skilled in the art.

Claims

1. A method for manufacturing a hydrophobic electronic component, comprising the steps of depositing a hydrophobic coating on the electronic component, the electronic component comprising a substrate, a chip positioned on a first side of the substrate, electrical connection terminals positioned on a second side of the substrate and electrically coupled to the chip using electrical tracks passing through the substrate, and a resin or cover covering the first side of the substrate and the chip.

2. The method according to claim 1, comprising the steps of: providing an element comprising a plurality of electronic components; Separate electronic components; bonding the electrical connection pads to the electrical connection terminals; as well as A hydrophobic coating is deposited to completely cover the electronic components. 3 . The method according to claim 2 , further comprising a subsequent step during which the hydrophobic coating deposited on the electrical connection pads is removed. The method of claim 2 , wherein the electrical connection pads are protected during deposition of the hydrophobic coating.

5. The method according to claim 1, comprising the steps of: providing an element comprising a plurality of electronic components; depositing a hydrophobic coating to cover the resin or cover and the second side of the substrate; a step of removing a hydrophobic coating deposited on the electrical terminals during execution; Optionally, bonding the electrical connection pads to the electrical terminals; as well as Separate the electronic components.

6. The method according to claim 1, comprising the steps of: providing an element comprising a plurality of electronic components; Separate electronic components; Depositing a hydrophobic coating to completely cover the electronic components; a step of removing a hydrophobic coating deposited on the electrical terminals during execution; as well as Optionally, the electrical connection pads are bonded to the electrical terminals.

7. The method of claim 1, wherein the hydrophobic coating is a composite material comprising a polymer material having a filler dispersed therein. The method according to claim 7 , wherein the filler is made of ceramic or graphene.

9. The method according to claim 7, wherein the filler is made of alumina or silica.

10. The method according to claim 1, wherein the substrate is made of resin. The method according to claim 1 , wherein the substrate is made of a composite material including a filler.

12. The method of claim 11, wherein the filler comprises glass fibers dispersed in the resin.

13. A method for manufacturing a hydrophobic electronic component, comprising the steps of: providing a component comprising a plurality of chips mounted to a first side of a substrate and covered by a resin cover; wherein the second side of the substrate comprises electrical connection terminals connected to the chip via electrical tracks passing through the substrate; bonding the electrical connection pads to the electrical connection terminals; separating the element into a plurality of electronic components; and A hydrophobic coating is deposited covering the first side, the second side, and the flanks of each electronic component.

14. The method according to claim 13, further comprising: The portion of the hydrophobic coating covering the electrical connection pad is removed.

15. The method of claim 13, further comprising protecting the electrical connection pads with a protective element before depositing the hydrophobic coating, and removing the protective element after depositing the hydrophobic coating.

16. An electronic component comprising: substrate; a chip positioned on the first side of the substrate; wherein the electrical connection terminals are positioned on the second side of the substrate and are electrically coupled to the chip using electrical tracks passing through the substrate; a resin or cover covering the first side of the substrate and the chip; as well as A hydrophobic coating covers at least the resin or the cover and the second side of the substrate between the electrical connection terminals.

17. The component of claim 16, wherein the hydrophobic coating is a composite material comprising a polymer material having a filler dispersed therein.

18. The component according to claim 17, wherein the filler is made of ceramic or graphene.

19. The component according to claim 17, wherein the filler is made of alumina or silica.

20. The component according to claim 16, wherein the substrate is made of resin.

21. The component of claim 16, wherein the substrate is made of a composite material including a filler.

22. The component of claim 21, wherein the filler comprises glass fibers dispersed in the resin.

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