METHOD OF MANUFACTURING ELECTRONIC COMPONENTS HAVING WETTABLE flanks
By forming cavities and depositing insulating and conductive material layers on a substrate, electronic components with wettable flanks are manufactured, solving the problems of connection quality and reliability during soldering and enabling visual inspection and reliable electrical connection.
Patent Information
- Application Number
- CN202510550392.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2025-02-18
- Filing Date
- 2025-04-29
- Publication Date
- 2025-11-18
AI Technical Summary
Existing technologies struggle to manufacture electronic components with wettable flanks, particularly in ensuring connection quality and reliability, and especially in achieving visual inspection during soldering.
By forming chips, cavities, or trenches on a substrate, depositing insulating and conductive material layers, and cutting to form electronic components with wettable flanks, including deposition and thinning steps of insulating and conductive material layers, the reliability and visual inspection of the connection area are ensured.
It enables reliable electrical connections and visual inspection of electronic components, ensuring soldering quality, and is suitable for advanced driver assistance systems, personal electronic products, and communication equipment in the automotive and medical fields.
Smart Images
Figure CN120977880A_ABST
Abstract
Description
[0001] Cross-references to related applications
[0002] This application claims priority to French patent application number 2405066, filed on May 17, 2024, entitled “Procédéde fabrication decomposantsélectroniquesàflancs mouillables”, which is incorporated herein by reference to the fullest extent permitted by law. Technical Field
[0003] This disclosure relates to the manufacture of electronic components having wettable fins. More specifically, this disclosure pertains to the manufacture of components intended for surface mounting (referred to as "leadless"), i.e., components that do not have visible connections once assembled onto an electronic board. These components include one or more connection metallizations on at least one surface, the connection metallizations being designed for soldering to corresponding connection areas of external devices (e.g., printed circuit boards or other components). Background Technology
[0004] In some applications, surface-mount components are required where the metallization of the connections, intended for soldering to external devices, extends to the sidewalls of the component. These components have wettable sidewalls. During assembly of the component in its environment (e.g., on a printed circuit board), the metallization of the connections (also known as electrical contacts) is welded or soldered to corresponding metal tracks or components on the surface of the printed circuit board. A portion of the solder material then adheres to the sidewalls of the component, allowing for visual inspection of the connection quality.
[0005] For example, this need exists in the automotive or medical fields. More generally, it exists in fields where it is desirable to ensure the correct assembly of components whose connections are not visible (connections are located under the component) and to guarantee the reliability of electrical connections once the circuit has been assembled in its environment (flip chip technology). Summary of the Invention
[0006] There is a need to improve, at least in part, certain aspects of known methods for manufacturing electronic components with wettable flanks.
[0007] This objective is achieved by a method for manufacturing an electronic component with wettable winglets, the method comprising the following steps:
[0008] a) Provide a substrate in which a chip is formed, the connection areas of the chip being disposed on the upper surface of the substrate, and possibly, conductive pads covering the connection areas.
[0009] b) Optionally, cavities or trenches are formed between the chips from the upper surface of the substrate.
[0010] c) forming a layer of a first insulating material on the substrate, the layer of the first insulating material covering the upper surface of the substrate, if step b) has been implemented, the layer of the first insulating material filling the cavity or the trench,
[0011] d) enabling access to the connection areas or to the conductive pads,
[0012] e) depositing a layer of a conductive material to couple the connection areas of two adjacent chips, if step b) has been implemented, the layer of the conductive material covering the cavity or the trench,
[0013] f) depositing a layer of a second insulating material on the conductive material and on the upper face of the substrate,
[0014] g) thinning the layer of the second insulating material until the conductive material is accessible,
[0015] h) separating the chips by cutting through the layer of the conductive material and by cutting through the first insulating material, if step b) has been implemented, the cutting being performed through the cavity or the trench, thereby obtaining electronic components having wettable flanks.
[0016] According to an embodiment, during step a), the connection areas are covered with conductive pads, and:
[0017] - step c) is performed by depositing a layer of the first insulating material on the upper surface of the substrate and on the conductive pads,
[0018] - step d) is performed by thinning the layer of the first insulating material to enable access to the conductive pads, and
[0019] - during step e), the layer of the conductive material is deposited on the conductive pads.
[0020] According to an embodiment, during step a), the connection areas are not covered with conductive pads, and:
[0021] - step c) is performed by depositing a layer of the first insulating material on the upper surface of the substrate and on the connection areas,
[0022] - step d) is performed by etching the layer of the first insulating material and possibly by thinning the layer of the first insulating material to enable access to the connection areas, and
[0023] - during step e), the layer of the conductive material is deposited on the connection areas.
[0024] According to an embodiment, the method comprises, before step g), a step during which the lower surface of the substrate is thinned and covered with a layer of additional insulating material.
[0025] According to an embodiment, the first layer of insulating material and / or the second layer of insulating material and / or the additional layer of insulating material is a layer of insulating resin, for example a layer of epoxy resin.
[0026] This object is also achieved by an electronic component with wettable flanks, comprising a chip formed in a substrate, the chip comprising connection areas arranged on an upper surface of the substrate; a first layer of insulating material covering the flanks of the substrate and the upper surface between the connection areas of the substrate; a second layer of insulating material covering the first layer of insulating material on the upper surface of the substrate; a layer of electrically conductive material arranged on each connection area and extending on the one hand further up to the upper surface of the electronic component and on the other hand up to the flanks of the electronic component.
[0027] According to an embodiment, the additional layer of insulating material covers a lower surface of the substrate.
[0028] According to an embodiment, the first layer of insulating material, the second layer of insulating material and / or the additional layer of insulating material is a layer of epoxy resin or a layer of phenolic resin in which are dispersed electrically insulating fillers, for example alumina or silica particles.
[0029] According to an embodiment, the layer of electrically conductive material is a layer of solderable material, for example a tin-based solderable material such as SnAgCu.
[0030] This object is also achieved by a method of assembly of such an electronic component with an external device, such as a printed circuit board, comprising the following steps:
[0031] - positioning a solder material between the electrically conductive material located on the upper surface of the electronic component and a connection element of the external device,
[0032] - soldering said solder material, whereby the solder material spreads on the connection element of the external device and on the wettable flanks of the electronic component.
[0033] This object is also achieved by the use of such an electronic component with wettable flanks in a motor vehicle, for example in an advanced driver assistance system, in a personal electronic product, in a communication equipment, such as a computer, a smartphone, an Internet of Things (IoT) or one of its peripherals.
[0034] This object is also achieved by a motor vehicle, a communication equipment, such as a computer, a smartphone, an Internet of Things (IoT) or one of its peripherals comprising such an electronic component with wettable flanks. BRIEF DESCRIPTION OF DRAWINGS
[0035] The above and other features and advantages will be described in the rest of the disclosure, given by way of example and without limitation, with reference to the appended drawings, in which:
[0036] FIG. 1A , FIG. 1B , FIG. 1C , FIG. 1D , FIG. 1E , FIG. 1F , FIG. 1G , FIG. 1H and FIG. 1I and FIG. 1J shows a cross-sectional view illustrating steps of a method of manufacturing an electronic component with wettable side wings according to a specific embodiment;
[0037] FIG. 2A , FIG. 2B , FIG. 2C , FIG. 2D , FIG. 2E , FIG. 2F , FIG. 2G , FIG. 2H and FIG. 2I and FIG. 2J shows a cross-sectional view illustrating steps of a method of manufacturing an electronic component with wettable side wings according to another specific embodiment;
[0038] FIG. 3A and FIG. 3B shows a cross-sectional view illustrating steps of a method of assembling an electronic component with wettable side wings with an external device according to a specific embodiment.
[0039] FIG. 4 shows a schematic cross-sectional and profile view of an electronic component with wettable side wings according to another specific embodiment.
[0040] In the various figures, the chip can be shown in its entirety or in a truncated form, in particular in the form of a half-chip, for ease of illustration. DETAILED DESCRIPTION
[0041] In the various figures, identical features are denoted with identical reference numerals. In particular, structural and / or functional features common to the various embodiments can have identical reference numerals and be deployed with identical structural, dimensional and material properties.
[0042] For the sake of clarity, only those steps and elements that are helpful for understanding the described embodiments are shown and described in detail.
[0043] Unless otherwise stated, when two elements are mentioned as being connected together, this means that they are directly connected, without any intermediate element other than a conductor, and when two elements are mentioned as being coupled together, this means that the two elements can be connected, or they can be coupled via one or more other elements.
[0044] In the following description, when referring to absolute position qualifiers such as "front", "back / backward", "top", "bottom", "left", "right", etc., or relative position qualifiers such as "top", "bottom", "upper", "lower", etc., or orientation qualifiers such as "horizontal", "vertical", etc., these refer to the orientation of the drawings, unless otherwise stated.
[0045] The expressions "about", "approximately", "substantially" and "approximately" mean plus or minus 10%, preferably plus or minus 5%, unless otherwise stated.
[0046] The method of manufacturing an electronic component 1000 with wettable side wings will now be described in further detail with reference to FIGS. 1A-1I and FIGS. 2A-2I The method of manufacturing an electronic component 1000 with wettable side wings will now be described in further detail with reference to
[0047] The method comprises at least the following steps:
[0048] a) providing a substrate 300 with chips 100 formed therein, the chips 100 having connection areas 107 arranged on an upper surface 305 of the substrate 300, FIG. 1A , 2A ) the conductive pads 117 can cover the connection areas 107, FIG. 1B ,
[0049] b) forming cavities 307 or trenches between the chips 100, FIG. 1C , 2B ) between the connection areas 107 of the chips 100,
[0050] c) forming a first layer 121 of insulating material to fill the cavities 307 or trenches with insulating material to cover the upper surface 305 of the substrate 300 between the connection areas 107, FIG. 1D , 2C ) between the connection areas 107 of the chips 100,
[0051] d) making the connection pads 107 FIG. 2D ) or the conductive pads 117 accessible, FIG. 1E ,
[0052] e) depositing a layer 122 of conductive material for covering the cavities 307 or trenches, in particular for covering the insulating material filling the cavities 307 or trenches, and for coupling the connection areas 107 of two adjacent chips 100, FIG. 1F , 2F ) between the connection areas 107 of the chips 100,
[0053] f) depositing a second layer 123 of insulating material on the conductive material 122 and on the upper surface 305 of the substrate 300, FIG. 1G , 2G ) between the connection areas 107 of the chips 100,
[0054] g) thinning the second layer of insulating material 123 until the conductive material 122 is accessible FIG. 1H , 2H ),
[0055] h) separating the chip 100 by cutting through the layer of conductive material 122 and through the cavity 307 or trench, whereby the conductive material 122 forms both the electrical connections and the wettable flanks of the electronic component 1000 FIG. 1I , 2I ).
[0056] Step b) is an optional step. It can or can not be implemented.
[0057] The implementation of step c) prevents any electrical failure (short circuit, leakage current, etc.) between the connections or other conductive elements connected to these connections and the face of the semiconductor substrate chip.
[0058] The layer of conductive material 122 deposited during step d) forms a bridge of conductive material between two adjacent chips. This bridge couples the two connection areas 107 of two adjacent chips 100.
[0059] When cutting this bridge during step e), the material forms part of the flanks of the electronic component 1000. A component 1000 with wettable flanks is thus obtained.
[0060] With this method, the part forming the wettable flanks has a height that can be easily adjusted according to the thickness of the deposition of the conductive material 122. The height of the wettable part can be made at least 100 pm.
[0061] The presence of the first layer of insulating material 121 between the conductive material 122 and the chip 100 avoids the risk of short circuits. In addition, the presence of this material in the cavity prevents the conductive material from collapsing during cutting. The device obtained has good mechanical resistance.
[0062] The method can also comprise, before step h), a step during which the back face of the substrate 300 is thinned and covered with an additional layer of insulating material 124.
[0063] During step c), the first layer of insulating material 121 is preferably deposited over the entire upper face 305 of the substrate 300, then structured. The insulating material fills the cavities 307 and covers the upper face 305 between the connection areas 107 of the substrate 300.
[0064] According to a first alternative embodiment, the substrate 300 provided at step a) comprises conductive pads 117 covering the connection areas 107.
[0065] According to this first alternative embodiment, for example, as FIGS. 1A-1IAs shown in the middle, the method can comprise at least the following steps:
[0066] a) providing a substrate 300 in which the chips 100 are formed, the connection areas 107 being arranged on the upper surface of the substrate 300 FIG. 1A ),
[0067] - covering the connection areas 107 with conductive pads 117 ("wafer bumps") FIG. 1B ),
[0068] b) forming cavities 307 or trenches between the chips 100 FIG. 1C ),
[0069] c) filling the cavities 307 or trenches with a first layer of insulating material 121, the first layer of insulating material 121 covering the upper surface of the substrate 300 and the conductive pads 117 FIG. 1D ),
[0070] d) thinning the first layer of insulating material 121 so that a portion of the conductive pads 117 is accessible FIG. 1E ),
[0071] e) depositing a layer 122 of conductive material to cover the cavities 307 or trenches and to couple the connection areas 107 of two adjacent chips 100, the layer 122 of conductive material being in contact with the conductive pads 117 FIG. 1F ),
[0072] f) depositing a second layer of insulating material 123 on the conductive material 122 FIG. 1G ),
[0073] g) thinning the second layer of insulating material 132 from the front surface so that the conductive material 122 is accessible FIG. 1H ),
[0074] h) separating the chips 100 by cutting through the layer 122 of conductive material and through the cavities 307 or trenches, whereby the conductive material 122 forms the electrical connections and the wettable flanks of the electronic components 1000 FIG. 1I ).
[0075] According to a second alternative embodiment, during step a) the connection areas 107 are not covered with conductive pads.
[0076] According to this second alternative embodiment, the method can comprise the following steps:
[0077] a) providing a substrate 300 in which the chips 100 are formed, the connection areas 107 being arranged on the upper surface 305 of the substrate 300 FIG. 1A ),
[0078] b) forming cavities 307 or trenches between the chips 100FIG. 2B ),
[0079] c) filling the cavities 307 or the trenches with a first layer of insulating material 121 covering the upper surface of the substrate 300 and the connection areas 107 FIG. 2C ),
[0080] d) making the connection areas 107 accessible, for example by laser etching and possibly by performing a thinning of the front face FIG. 2E ),
[0081] e) depositing a layer 122 of electrically conductive material to cover the cavities 307 and to couple the connection areas 107 of two adjacent chips 100 FIG. 2F ),
[0082] f) depositing a second layer 123 of insulating material on the electrically conductive material 122 FIG. 2G ),
[0083] g) thinning the second layer 123 of insulating material from the front face to make the electrically conductive material 122 accessible FIG. 2H ),
[0084] h) separating the chips 100 by cutting through the layer 122 of electrically conductive material and through the cavities 307 or the trenches, whereby the electrically conductive material 122 forms the electrical connections and the wettable flanks of the electronic component 1000 FIG. 2I )。
[0085] The different elements and steps of the different variant examples of the method of manufacturing an electronic component 1000 with wettable flanks will now be described in further detail.
[0086] The base structure provided at step a) comprises an electronic chip 100 formed from a semiconductor substrate 300, for example made of silicon. It can also be SiC, glass, GaN or sapphire.
[0087] The thickness of the substrate 300 is for example in the range from 300 to 1200 pm, for example the thickness is approximately 725 pm.
[0088] The substrate 300 comprises a first surface 305 (upper surface or front face) and a second surface 303 (back face or lower surface).
[0089] The chip 100 is formed on the front face 305 of the substrate 300.
[0090] The chip 100 can comprise one or more discrete components. The discrete component(s) are for example chosen among transistors, diodes, filters, etc. The chip 100 can comprise one or more electronic circuits. The chip 100 makes it possible to implement different electronic functions.
[0091] At step a), the manufacturing of the discrete component(s) and / or of the integrated circuit forming the component 1000 is completed. The chips 100 are formed in the same substrate 300 and have not yet been singulated.
[0092] One or more connection areas 107 are formed on the upper surface 305 of the substrate 300 to connect the chips 100 to external elements / devices 400 (electronic chips or devices).
[0093] The electrical connection areas 107 are also called "UBM" (for "Under Bump Metallization") or "bump pads". The electrical connection areas 107 are made of an electrically conductive material specifically adapted to accommodate the electrically conductive pads 117 and in particular have a good adhesion to the electrically conductive pads 117. The electrical connection areas 107 contain at least one of the following elements: gold, titanium, nickel or copper. Preferably, the electrical connection areas contain gold.
[0094] The electrical connection areas 107 are at a distance from the sidewalls of the chips, for example, from 10 to 30 pm. The electrical connection areas 107 can be located on the upper surface 305 of the substrate 300 or be flush with the upper surface 305 of the substrate 300 (i.e., reach the level of the upper surface 305).
[0095] During step a), the connection areas 107 can have a free upper surface (i.e., not covered, as shown in FIG. 2A ) or they can be covered with the electrically conductive pads 117 (as shown in FIG. 1B ).
[0096] The electrically conductive pads 117 can in particular have the shape of a bump. Alternatively, it can be an electrically conductive element having another shape, such as, for example, a column or a cube.
[0097] The electrically conductive pads 117 are made of an electrically conductive and "wettable" material (i.e., solderable or weldable), i.e., a material on which soldering can be performed.
[0098] The electrically conductive pads 117 are advantageously soldered on the electrical connection areas 107. For example, the electrically conductive pads are made of a solderable material based on tin, typically SnAgCu.
[0099] At this stage, the chips 100 have not yet been protected by a package made of an insulating material.
[0100] During step b), cavities 307 or trenches (not shown) are formed in the substrate 300 to separate the adjacent chips 100. The cavities 307 or trenches delimit the flanks 304 of the substrate 300 for each component 1000.
[0101] A cavity 307 is formed in the substrate 300, the cavity 307 defining the lateral profile of the chip 100 of the component 1000. The cavity 307 extends from the upper surface 305 of the substrate 300. According to an example, the depth of the cavity 307 corresponds to the desired thickness of the chip of the component 100. According to an example, the depth of the cavity 307 is about 100 pm or 300 pm. This depth can be modified according to the desired application. The thickness of the cavity 307 formed at step b) is preferably in the range from 50 to 80 pm. This thickness can be modified according to the desired application.
[0102] The trench completely crosses the substrate. The trench defines the lateral profile of the chip 100. The thickness of the trench is for example in the range from 20 to 80 pm.
[0103] Step b) can be performed by means of a step of partial or total cutting / etching of the substrate. This step can be performed by means of a cutting or etching device. The cutting device is for example a mechanical etching tool such as a saw or a laser etching tool. The sawing can be performed with one blade or two blades.
[0104] According to another embodiment, it can be a laser grooving, or a laser cutting, or a plasma cutting. These different cutting methods can also be shared.
[0105] The formation of the space can also be performed by means of a step of cutting by means of laser introduction of dislocations, called a step of "stealth cutting", and a subsequent step of expansion. The so-called "stealth cutting" step consists in creating dislocations in the substrate within the cutting line with a specific laser. These dislocations are defects present across the thickness of the substrate which, under the effect of mechanical stress, will make it possible to separate the chips. It is then sufficient to stretch the adhesive support to separate the chips and to deposit material.
[0106] In this case, the substrate 300 can be brought to the final product thickness before the stealth cutting operation.
[0107] During step c), the cavity 307 or the trench is filled with a first layer of insulating material 121.
[0108] The first layer of insulating material 121 can also cover the upper surface of the substrate 300.
[0109] To do this, a layer of insulating material 121 is deposited on the first surface 305 of the substrate 300, in the cavity 307. The first layer of insulating material 121 covers the connection area 107 and possibly the conductive pads 117. At the end of step c), these last elements are arranged within the insulating material. The first layer 121 forms a first part of the encapsulation of the component 1000. This first encapsulation part thus protects the upper surface of the component 1000, as well as a part of the flanks.
[0110] The insulating material can be deposited by means of pressure or by vacuum molding.
[0111] The insulating material can comprise an electrically insulating resin. The resin can be a thermosetting resin or a thermoplastic resin. The material will be chosen so as not to be meltable in the temperature range of use of the electronic component. The resin can be chosen from the group comprising epoxy-based resins, and phenolic-based resins, acrylic-based resins.
[0112] The insulating material can also comprise electrically insulating particles. These particles are, for example, oxide particles, and in particular alumina or silica particles.
[0113] The polymerization is, for example, a UV polymerization step or a polymerization by thermal activation.
[0114] Annealing can be performed after step c).
[0115] According to a first alternative embodiment, during step d), a portion of the first insulating material layer 121 is removed to make the conductive pads 117 accessible. This step can be performed by means of a step of front thinning of the insulating material 121.
[0116] According to a second alternative embodiment, during step d), a portion of the first insulating material layer 121 is removed to make the connection areas 107 accessible. This step can be performed by means of a laser etching step and possibly by means of a step of front thinning of the insulating material 121. These two steps (thinning and etching) can be performed in this order or in the reverse order.
[0117] The laser etching results in the formation of an opening in the form of a conical body in the first insulating material layer 121. FIG. 2D ).
[0118] The front thinning achieved at step d) can be performed by grinding.
[0119] During step e), a layer 122 of electrically conductive material is deposited on the insulating material layer 121. This layer 122 of electrically conductive material is deposited to couple the connection areas 107 of two adjacent chips 100. The electrically conductive material 122 forms a bridge (or a joint) between the chips. The layer 122 of electrically conductive material is in contact with the layer 121 of insulating material. In other words, there is no intermediate element between these two layers.
[0120] The electrically conductive material 122 can be in direct contact with the connection areas 107, or coupled to the connection areas 107 via the conductive pads 117.
[0121] The electrically conductive material 122 is, for example, a solderable (or weldable) material. In particular, it is tin or a tin-based alloy, such as SnAgCu. It can also be a lead alloy or an antimony alloy. It can be SnPb or SnSb.
[0122] The conductive material 122 can comprise a flux.
[0123] The material can be deposited by spreading a paste, for example by a stencil deposition, the openings of which are located in front of the connection areas and in front of the joints to be formed. The stencil is for example a stainless steel or nickel sheet provided with openings.
[0124] The solderable conductive material can be soldered on the connection areas 107, or, if applicable, on the conductive pads 117.
[0125] During step f), a second layer of insulating material 123 is deposited on the conductive material 122 and on the front side of the chip 100.
[0126] The first and second layers of insulating material 121, 123 can be made of the same material. For example, the same material is an insulating resin, such as one of those previously described.
[0127] A previous thinning step is then performed to make the conductive material 122 accessible (step g)). This material 122 forms, on the front, the electrical contacts of the package of the component 1000, also called connection metallization. The electrical contacts of the front make it possible to connect the chip to external elements 400.
[0128] The thinning can be performed to reach a desired height of the conductive material.
[0129] The front thinning step can be performed by lapping.
[0130] The method can also comprise a step of thinning the substrate 300 on the back 303. To do this, the structure is turned over and attached to a support by its front 305. This support is for example an adhesive tape. Then, the structure is thinned from its back 303 so that the substrate 300 has its final thickness. According to an example, the structure 301 is thinned all the way to the bottom of the cavity 307.
[0131] In addition, the method can advantageously comprise an additional step during which an additional insulating layer 124 is deposited on the back 303 of the structure to form the rear of the package of the component 1000. Thus, all the surfaces of the substrate 300 are protected. The first insulating layer 121 forms the flanks of the package and at least part of the front side of the package. The additional layer 124 forms the rear of the package. The second insulating layer 123 forms another part of the front side of the package.
[0132] The additional insulating layer 124 is a layer made of an electrically insulating material. The insulating material of the additional layer 124 can be the same as the insulating material of the first layer 121 and / or of the second layer 123. According to another example, the materials of the insulating layers 121, 123, 124 are different. The additional insulating layer 124 is for example a layer of resin.
[0133] During step h), singulation of the electronic component 1000 is performed by cutting through the conductive material 122 and the first insulating resin layer 121. The cutting is performed in the cavity 307 or in the trench.
[0134] The components 1000 are thus separated from each other.
[0135] The conductive material 122 is thus exposed, ensuring the wettable function of the flanks of the electronic component 1000.
[0136] The conductive material 122 also allows direct contact on the front face of the package, as it is coupled / connected to the electrical connection areas 107 of the chip 100.
[0137] During the aforementioned steps, and in particular during the cutting step, the structure can be positioned on an adhesive. The adhesive used can be an adhesive sensitive to ultraviolet (UV) radiation for cutting applications (“UV cutting tape”).
[0138] FIG. 1I 、 FIG. 2I and FIG. 3A An electronic component 1000 with wettable flanks obtained by this method is illustrated in a partial and simplified cross-sectional view.
[0139] The electronic component 1000 comprises an electronic chip 100 formed in a substrate 300, and a package made of insulating material protecting the chip 100.
[0140] The package comprises at least a first layer 121 made of insulating material, which covers the flanks of the substrate 300, and a portion of the upper surface 305 of the substrate 300. The package can also comprise a second layer 123 made of insulating material, which covers the portion of the first layer 121 positioned on the upper surface 305 of the substrate 300, and / or an additional layer 124 made of insulating material, which covers the back face 303 of the substrate 300.
[0141] The conductive material forms on the one hand the wettable flanks of the package, and on the other hand the metallization on the front face of the package. For example, the conductive material is embedded in the package. It is directly coupled or connected to the connection areas 107, or to the metal pads 117 positioned on the connection areas 107. It further extends through the first insulating layer 121, and if applicable, through the second insulating layer 123, up to the upper surface of the package (to enable the connection of the chip 100 to external elements / devices 400), on the one hand, or up to the flanks of the package, to form the wettable flanks of the package, on the other hand.
[0142] The layer of electrically conductive material 122 is not in direct contact with the substrate 300. The first layer of insulating material 121 is positioned between the substrate 300 and the layer of electrically conductive material 122.
[0143] When step b) is implemented, the sides of the component 1000 are successively formed from the insulating material 121 and the electrically conductive material 122. FIG. 1J FIG. 2J FIG. 3A When step b) is not implemented, the flanks of the component 1000 are successively formed from the flanks of the substrate 300, the insulating material 121 and the electrically conductive material 122 FIG. 4 , i.e. the insulating material 121 does not cover the flanks of the substrate 300.
[0144] The component 1000 is a so-called integrated component.
[0145] The components 1000 obtained are surface-mount devices (or SMDs) of the "flip-chip" type, i.e. they can be attached to an external element / device 400 (for example a printed circuit board) through their upper surface, i.e. the surface on which the contacts of the package are arranged.
[0146] Such components 1000 are particularly advantageous for guaranteeing the reliability of the electrical connections once the circuit has been assembled in its environment. They make it easy to check whether the soldering of the component 1000 ("leadless component") on another device 400 has been performed correctly.
[0147] FIG. 3A and FIG. 3B The steps of a method of assembling a component 1000 ("leadless component") on an external device 400 (for example a printed circuit board (or PCB) or another component) are illustrated.
[0148] The external device 400 comprises a substrate 401 covered with tracks 402. The tracks 402 are for example made of copper. In particular, the tracks 402 are arranged to protrude from the area to which the component 1000 is attached. In other words, the tracks 402 are clearly visible when the assembly (component 1000 and external device 400, such as a PCB) is observed in top view.
[0149] The soldering material 500 is positioned between the component 1000 and the tracks 402 of the external device 400 FIG. 3A . During the soldering, the soldering material 500 not only rises along the material 122 forming the wettable flanks of the component 1000, but also rises on the tracks 402 of the external device 400 FIG. 3B , which makes it possible to verify whether the soldering has been performed correctly.
[0150] The soldering points are visible in top view by automated optical inspection (AOI).
[0151] The use of components with wettable flanks also helps to avoid the need for X-ray inspection of so-called "double-sided" PCBs, i.e. PCBs on which components are soldered on both sides.
[0152] Such electronic components 1000 can be applied in many industrial fields, in particular the automotive field, for personal electronic products, in particular the field of communication equipment, computers and peripherals.
[0153] For example, this can be a 5G connected device or more generally a connected device.
[0154] It can also be an Advanced Driver Assistance System (ADAS).
[0155] The electronic chip can be used for a smartphone or the Internet of Things (IoT). For example, the device is connected by 5G, WIFI or Ultra Wide Band (UWB).
[0156] The chip can also be advantageous for other fields, such as for example the industrial field, in particular for green energy.
[0157] Such applications are given by way of illustration only and are not limiting.
[0158] A number of embodiments and variant examples have been described. The person skilled in the art will understand that certain features of these various embodiments and variant examples can be combined and that other variant examples will occur to the person skilled in the art.
[0159] Finally, the actual implementation of the described embodiments and variant examples is within the capabilities of the person skilled in the art, based on the functional indications given above.
Claims
1. A method for manufacturing an electronic component having wettable winglets, comprising: a) Provide a substrate in which a chip is formed, wherein a connection region of the chip is disposed on an upper surface of the substrate, and possibly, conductive pads cover the connection region. c) Forming a first insulating material layer on the substrate; d) Enables the connection area or conductive pads to be connected; e) Deposit a layer of conductive material on the first insulating material layer, the layer of conductive material being in contact with the first insulating material layer to couple the connection regions of two adjacent chips; f) Deposit a second insulating material layer on the conductive material and the substrate; g) Thinning the second insulating layer until the conductive material can be connected; and h) The chip is separated by cutting through the conductive material layer and the first insulating material layer, thereby obtaining an electronic component with wettable winglets.
2. The method of claim 1, wherein during step a), the connection area is covered with conductive pads; Step c) is performed by depositing the first insulating material layer on the upper surface of the substrate and on the conductive pads; Step d) is performed by thinning the first insulating material layer to allow the conductive pads to be connected; and During step e), a layer of the conductive material is deposited on the conductive pad.
3. The method of claim 1, wherein step c) is performed by depositing the first insulating material layer on the upper surface of the substrate and on the connection region; Step d) is performed by etching the first insulating material layer and, possibly by thinning the first insulating material layer to allow the connection area to be accessed; and During step e), a layer of the conductive material is deposited on the connection region.
4. The method of claim 1, wherein prior to step g), the lower surface of the substrate is thinned and covered with an additional insulating material layer during its duration.
5. The method of claim 1, wherein the first insulating material layer, the second insulating material layer, or the additional insulating material layer is an insulating resin layer.
6. The method of claim 5, wherein the insulating resin layer is an epoxy resin layer.
7. The method of claim 1, wherein the method includes step b) located between step a) and step c), during step b), during which cavities or trenches are formed between the chips from the upper surface of the substrate; and During step c), the first insulating material layer fills the cavity or trench and covers the upper surface of the substrate.
8. An electronic component having wettable flanks, comprising a chip formed in a substrate, the chip including connection regions disposed on an upper surface of the substrate, a first insulating material layer covering the flanks of the substrate and the upper surface between the connection regions of the substrate, a second insulating material layer covering the first insulating material layer on the upper surface of the substrate, and a layer of conductive material disposed on each connection region and further extending to the upper surface of the electronic component and to the flanks of the electronic component; and The flanks of the electronic component are formed from the first insulating material layer and the conductive material, or from the first insulating material layer, the conductive material and the substrate.
9. The electronic component of claim 8, wherein an additional insulating material layer covers the lower surface of the substrate.
10. The electronic component of claim 8, wherein the first insulating layer, the second insulating layer, or the additional insulating layer is an epoxy resin layer or a phenolic resin layer in which electrically insulating fillers are dispersed.
11. The electronic component of claim 10, wherein the electrically insulating filler is alumina or silicon dioxide particles.
12. The electronic component of claim 8, wherein the conductive material layer is a solderable material layer, the solderable material being, for example, a tin-based solderable material.
13. The electronic component of claim 12, wherein the tin-based solderable material is SnAgCu.
14. A method for assembling an electronic component and an external device as described in claim 7, the method comprising: The welding material is positioned between the conductive material on the upper surface of the electronic component and the connecting element of the external device. as well as Solder is used to weld the welding material, thereby allowing the welding material to diffuse onto the connecting elements of the external device and the wettable flanks of the electronic component.
15. The assembly method of claim 14, wherein the external device is a printed circuit board.
Citation Information
Patent Citations
CONTROLLED RELEASE compositions FOR THE ADMINISTRATION OF THERAPEUTIC AGENTS TO RUMINANTS
FR2405066A1