Electronic chip

Abstract

Electronic Chip This description relates to a chip (100) comprising: - a substrate (101); - at least one optical component (102) formed on a first face of said substrate (101); - at least one electrical connection pad (103) formed on said first face of said substrate (101), and surmounted by an electrical connection means (104); and - a protective glass (105) disposed above said at least one component (102) and fixed to said first face of said substrate (101) by means of an adhesive layer (106) extending at least partially to the periphery of said at least one component (102), said glass (105) comprising at least one opening (107) adapted to make accessible said electrical connection means (104). Figure for the abbreviation: Fig. 1

Description

Title of the invention: Electronic chip technical field

[0001] This description relates generally to electronic and / or optical systems and devices, and in particular to electronic / optical chips and their manufacturing processes. More specifically, this description relates to an electronic chip comprising optical components and a protective glass for these optical components. Previous technique

[0002] Optical components, such as optical sensors, are most often used within an electronic and optical chip. These components can be fragile, and their operation can be impaired by dust or debris.

[0003] It would be desirable to be able to improve, at least in part, the realization of electronic chips comprising optical components, and the implementation of their manufacturing processes. Summary of the invention

[0004] There is a need for chips comprising optical components in which the optical components are protected from dust and debris.

[0005] There is a need for chips comprising optical components in which the optical components are protected from dust and debris by a protective glass.

[0006] There is a need for manufacturing processes for such chips, in which the protective glass is installed before the formation of dust or debris.

[0007] One embodiment overcomes all or part of the drawbacks of known chips comprising optical components.

[0008] One embodiment provides a chip comprising: - a substrate; - at least one optical component formed on a first face of said substrate; - at least one electrical connection pad formed on said first face of said substrate, and surmounted by an electrical connection means; and - a protective glass arranged above said at least one component and fixed to said first face of said substrate by means of a layer of glue extending at least in part to the periphery of said at least one component, said glass comprising at least one opening adapted to make said means of electrical connection accessible.

[0009] Another embodiment provides a method for manufacturing a chip comprising the following successive steps: - provide a structure comprising at least one optical component disposed on a first face of a substrate and at least one electrical connection pad disposed on said first face of said substrate, said at least one electrical connection pad being surmounted by an electrical connection means; - to apply a layer of glue extending at least partially to the periphery of said at least one component; and - place a protective glass over said at least one component and fix it by means of said layer of glue, said glass including at least one opening suitable to make said means of electrical connection accessible.

[0010] According to one embodiment, said layer of glue has a thickness less than the height of said electrical connection means.

[0011] According to one embodiment, said electrical connection means comprises one or more welding balls or a conductive pillar.

[0012] According to one embodiment, a top surface of said adhesive layer does not exceed more than 70% of the thickness of said protective glass.

[0013] According to one embodiment, the glue of said glue layer is an electrically insulating glue.

[0014] According to one embodiment, said at least one opening is of overall rectangular shape.

[0015] According to one embodiment, said at least one opening is of overall open rectangular shape.

[0016] According to one embodiment, said at least one opening is adapted to make accessible an electrical connection means surmounting another connection pad.

[0017] According to one embodiment, said at least one opening is obtained by implementing a reactive ion etching operation or a laser etching operation.

[0018] According to one embodiment, said window is a glass window without treatment or a glass window comprising one or more optical filters.

[0019] According to one embodiment, said at least one optical component is an optical sensor.

[0020] Yet another embodiment provides for an electronic device comprising a chip described above and a housing.

[0021] According to one embodiment, said connection means is connected to a connection terminal of said housing via a wire weld.

[0022] Yet another embodiment provides a method for manufacturing a device described above, comprising the method described above. Brief description of the drawings

[0023] These features and advantages, as well as others, will be described in detail in the following description of particular embodiments, given by way of non-limiting example, in relation to the accompanying figures, among which:

[0024] [Fig.1] represents an embodiment of an electronic chip;

[0025] Fig. 2 shows two views (A) and (B), each illustrating an embodiment of a protective glass for an electronic chip;

[0026] [Fig. 3] represents five views (A) to (E), each illustrating a method of implementing a process for manufacturing the chip of [Fig. 1]; and

[0027] [Fig.4] represents three views (A), (B) and (C) illustrating different options for connecting the chip of [Fig.1]. Description of the implementation methods

[0028] The same elements have been designated by the same reference numerals in the different figures. In particular, the structural and / or functional elements common to the different embodiments may have the same reference numerals and may have identical structural, dimensional and material properties.

[0029] For the sake of clarity, only the steps and elements useful for understanding the described embodiments have been represented and are detailed.

[0030] Unless otherwise specified, when referring to two elements connected together, this means directly connected without intermediate elements other than conductors, and when referring to two elements connected (in English "coupled") together, this means that these two elements can be connected or linked through one or more other elements.

[0031] In the following description, when reference is made to absolute position qualifiers, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative position qualifiers, such as the terms "above", "below", "superior", "inferior", etc., or to orientation qualifiers, such as the terms "horizontal", "vertical", etc., reference is made, unless otherwise specified, to the orientation of the figures.

[0032] Unless otherwise specified, the expressions "approximately", "roughly", and "in the order of" mean within 10%, preferably within 5%.

[0033] The embodiments described below relate to the construction of a chip comprising one or more optical components, for example, several optical lenses, and, at the periphery of these components, electrical connection pads. These embodiments relate, more particularly, to the protection of these optical components from dust and debris. In these embodiments, an optically transparent screen, for example made of glass, is used to protect these optical components. This screen is fixed above the optical components by via a layer of glue and includes openings to allow electrical connection of the electrical connection pads.

[0034] Moreover, the embodiments described below are particularly suited to any optical and electronic device adapted to use optical components, for example to capture images (camera).

[0035] Moreover, the embodiments described above are particularly suitable for use in any type of industrial market where a chip comprising an optical component is used. More particularly, such a chip can be intended for: - the automotive industry, for example in the field of automotive electrification or in the field of Advanced Driver Assistance Systems (ADAS); - the industrial industry, for example in the field of green energy, in the field of infrastructure electrification, the Internet of Things (IoT) and Smart Homes, where electricity and energy consumption and data exchange are key elements; - the personal electronics industry, for example in the field of mobile telephony and the Internet of Things (IoT), as well as in the field of broadband interfaces; and - the communications equipment, computer and peripherals industry, for example in the field of infrastructure and data centers, and in the field of low Earth Orbit (LEO) satellites.

[0036] Fig. 1 is a cross-sectional view of an embodiment of an electronic chip 100 arranged in a housing 110.

[0037] The electronic chip 100 is formed from a substrate 101, for example a silicon substrate. On one face of the substrate 101, at least one optical component 102 is formed. This optical component is, for example, a component adapted to capture an image, such as an image sensor comprising an array of optical components. In one embodiment, this optical component is a photodetection pixel array. Each photodetection pixel comprises, for example, a microlens.

[0038] The electronic chip 100 further comprises at least one, generally several, connection pads 103 for connecting it to other electronic devices such as the housing 110. In one embodiment, the connection pad(s) 103 are arranged around the periphery of the optical component 102. Each connection pad 103 is surmounted by an electrical connection means 104. In one example, this connection means is a solder ball. Other types of connection means are described in relation to [Fig. 4].

[0039] The electronic chip 100 further comprises a protective glass 105 disposed above the optical component 102. In one example, the glass 105 is made of an optically transparent material, such as glass. In another example, the glass 105 can be treated to incorporate one or more optical filters. An advantage of using such a protective glass 105 is that it protects the optical component 102 from dust and debris that may occur during the manufacturing process of the chip 100. Indeed, this glass 105 can be installed as soon as the manufacturing of the component 102 is complete. A method for manufacturing the chip and, in particular, for installing the glass 105 is described in relation to [Fig. 3].

[0040] In one embodiment, the glass 105 is fixed to the substrate 101 by means of an adhesive layer 106. In another embodiment, the adhesive layer 106 is disposed over at least a portion of the periphery of the optical component 102 and at the connection pads 103. However, the thickness of the adhesive layer 105 is less than the height of the connection means 104, so as to leave the top of the connection means accessible. In one example, the adhesive 106 is an electrically insulating adhesive.

[0041] According to one embodiment, the protective glass 105 includes one or more openings 107 adapted to allow access to the connection means 104. Examples of openings 107 are described in detail in relation to [Fig.2].

[0042] According to one embodiment, the protective glass 105 has a width which is, at most, equal to the width of the substrate 101 of the chip 100. According to one example, the protective glass may have a width less than the width of the substrate 101. This is an advantage of this embodiment.

[0043] The housing 110 is a simplified housing comprising only a substrate 111 and side walls 112. In one example, the substrate 111 is a laminated substrate. In another example, the side walls 112 are made of resin. The substrate 111 includes, on its upper face, one or more connection pads.

[0044] The chip 100 is mounted in the housing 110 by being fixed to the upper face of the substrate 111 by means of, for example, a layer of glue 113.

[0045] In one embodiment, the chip 100 is further electrically connected to the housing 110. More specifically, the connection pads 103 of the chip 100 are electrically connected to connection pads 103 of the housing via their connection means 104 and a connecting wire 120. In one embodiment, the connecting wire 120 is a solder wire, for example, installed by a wire bonding process. In one embodiment, a first end of the wire 120 is connected, for example, soldered, to a connection means 104 through the opening(s) 107 of the protective glass 105, and a second end of the wire 120 is connected, for example, soldered, to a connection pad of the substrate 111 of the housing 110.

[0046] Fig. 2 comprises two views (A) and (B), each illustrating, partially or in part, totality, examples of a protective glass 200 of the type of the protective glass 105 described in relation to [Fig.1].

[0047] According to one embodiment, the openings are generally rectangular in shape, but may have a general shape of the same type as the general shape in top view of a connection block and its connection means 250 (symbolized by black blocks in [Fig.2]), such as for example of overall circular, oval, or polygonal shape.

[0048] In view (A) of [Fig.2], the window 200 includes two types of openings 201 and 202 allowing access to connection pads and their connection means 250.

[0049] According to a first example, the opening 201 is intended to make accessible only one connection pad and its connection means 250. According to a second example, the opening 202 is intended to make accessible several connection pads and their connection means 250.

[0050] In view (B) of [Fig.2], only a part of the glass 200 is shown and includes a type of opening 203. The opening 203 is an "open" opening on the edge of the protective glass 200. Indeed, the opening 203 is not entirely surrounded by walls formed by the glass 200.

[0051] According to a first example, the opening 203 is intended to make accessible only one connection pad and its connection means 250. According to a second example, the opening 203 can be intended to make accessible several connection pads and their connection means 250.

[0052] Figure 3 comprises five views illustrating an implementation of a method for manufacturing a chip of the type of chip 100 described in relation to Figure 1, and part of its installation in a package of the type of package 110 described in relation to Figure 1. More particularly, Figure 3 shows in detail the installation of a protective glass for a chip of the type of chip 100.

[0053] In step (A) of [Fig. 3], a substrate 301 comprising one or more optical components 302 formed on one of its faces, hereafter referred to as the upper face, is provided. The substrate 301 further comprises one or more connecting pads 303 formed on this same upper face. According to a preferred example, the connecting pads 303 are formed on the periphery of the optical component(s) 302. Step (A) may include the manufacturing processes for the component(s) 302 and the connecting pad(s) 303.

[0054] In the step of view (B) of [Fig.3], connection means 304 are formed on the connection pads 303. Examples of connection means are described in relation to [Fig.4].

[0055] In the step of view (C) of [Fig.3], a layer of adhesive 305 intended to fix a protective glass is deposited on a part of the upper face of the substrate 301. More particularly, this layer of adhesive 305 is disposed at least in part around the periphery of the optical component(s) 302. According to one example, the thickness of the layer of adhesive 305 is less than the height of the connection means 304.

[0056] In step (D) of [Fig. 3], a protective glass 306 of the type of the protective glass 105 described in relation to [Fig. 1] is deposited on the structure obtained in step (C). More particularly, the protective glass 306 includes openings 307 of the type of the openings 107 described in relation to [Fig. 1], and these openings are arranged so as to make the connection means 304 accessible.

[0057] The glass 306 is fixed to this structure by means of the adhesive layer 305, and is, for example, pressed onto the adhesive layer 305. The adhesive layer 305 may have overflowed at the openings 307, either due to the pressing or simply to the weight of the glass 306. In one embodiment, the thickness of the adhesive layer 305 at the openings 307 does not exceed 70% of the thickness of the glass 306. Furthermore, in one embodiment, the thickness of the adhesive layer 305 at the openings 307 does not exceed the height of the connecting means 304.

[0058] At the end of the viewing step (D), the installation of the glass 306 is complete, and if no other components need to be formed on the chip thus obtained, then the chip manufacturing process is complete.

[0059] In step (E) of [Fig. 3], the chip obtained at the end of step (D) is installed in a package of which only the substrate 309 is shown. According to one example, the chip is fixed to the substrate 309, for example using a bonding process.

[0060] Furthermore, in the viewing step (E), the chip's connection means 304 are connected to the package's connection pads via a connecting wire. According to one example, a wire soldering process is implemented.

[0061] Fig. 4 comprises three views (A), (B) and (C) illustrating cross-sectional views of different types of connection means of the type of connection means 104 described in relation to Fig. 1.

[0062] Each view (A), (B) and (C) represents a part of a substrate 401 comprising on its upper face an optical component 402 and a connection pad 403, for example metallic, for example copper.

[0063] In view (A) of [Fig. 4], the connecting means is formed by a ball 404 of electrically conductive material, such as a solder ball, or a stack of several balls 404. Alternatively, the ball or balls 404 are balls Metallic elements welded to the 403 connection pad. The 404 ball(s) are, for example, connecting elements of the type commonly referred to by the English term "stud bump" or "stud bail," also called a wiring ball. Such an element corresponds, for example, to the end of a metallic wire, for example, copper or gold, formed using wire bonding equipment. The end of the metallic wire is, for example, melted to form a ball, the ball is welded to the 403 connection pad, and the wire is then broken to leave the ball in place. Such balls can be stacked by repeating the operation.

[0064] In view (B) of [Fig. 4], the connection means is formed by a conductive pillar 405. By way of example, the conductive pillar 405 can be formed by one or more layers of electrically conductive materials. The conductive pillar 405 is, for example, a copper pillar.

[0065] In view (C) of [Fig.4], the connection means is formed by a ball 406 of electrically conductive material, such as a solder ball, part of which has been flattened, for example an upper part.

[0066] Various embodiments and variations have been described. A person skilled in the art will understand that certain features of these various embodiments and variations could be combined, and other variations will become apparent to a person skilled in the art.

[0067] Finally, the practical implementation of the embodiments and variants described is within the reach of a person skilled in the art, based on the functional indications given above.

Claims

Demands

1. Chip (100) comprising: - a substrate (101, 301); - at least one optical component (102; 302) formed on a first face of said substrate (101, 301); - at least one electrical connection pad (103; 303) formed on said first face of said substrate (101, 301), and surmounted by an electrical connection means (104; 304); and - a protective glass (105; 306) disposed above said at least one component (102; 302) and fixed to said first face of said substrate (101, 301) by means of a layer of glue (106; 305) extending at least in part to the periphery of said at least one component (102; 302), said glass (105; 306) comprising at least one opening (107; 201, 202, 203; 307) adapted to make said electrical connection means (104; 304) accessible.

2. Chip according to claim 1, wherein said glue layer (106; 305) has a thickness less than the height of said electrical connection means (104; 304).

3. Chip according to claim 1 or 2, wherein said electrical connection means (104; 304) comprises one or more solder balls or a conductive pillar.

4. Chip according to any one of claims 1 to 3, wherein an upper face of said adhesive layer (106; 305) does not exceed more than 70% of the thickness of said protective glass (105; 306).

5. Chip according to any one of claims 1 to 4, wherein the glue of said glue layer (106; 305) is an electrically insulating glue.

6. Chip according to any one of claims 1 to 5, wherein said at least one opening (107; 201, 202, 203; 307) is of overall rectangular shape.

7. Chip according to any one of claims 1 to 6, wherein said at least one opening (203) is of overall open rectangular shape.

8. Chip according to any one of claims 1 to 7, wherein said at least one opening (107; 201, 202, 203; 307) is adapted to make accessible an electrical connection means (104; 304) surmounting another connection pad (103; 303).

9. Chip according to any one of claims 1 to 8, wherein said at least one opening (107; 201, 202, 203; 307) is obtained by implementing a reactive ion etching operation or a laser etching operation.

10. Chip according to any one of claims 1 to 9, wherein said window (105; 306) is an untreated glass window or a glass window comprising one or more optical filters.

11. Chip according to any one of claims 1 to 10, wherein said at least one optical component (102; 302) is an optical sensor.

12. Electronic device comprising a chip according to any one of claims 1 to 11 and a housing.

13. Device according to claim 12, wherein said connection means is connected to a connection terminal of said housing via a wire-by-wire solder.

14. A method for manufacturing a chip comprising the following successive steps: - providing a structure comprising at least one optical component (102; 302) disposed on a first face of a substrate (101, 301) and at least one electrical connection pad (103; 303) disposed on said first face of said substrate (101, 301), said at least one electrical connection pad (103; 303) being surmounted by an electrical connection means (104; 304); - depositing a layer of adhesive (106; 305) extending at least partially to the periphery of said at least one component (102; 302); and - to place a protective glass (105; 306) over said at least one component (102; 302) and fix it by means of said layer of glue (106; 305), said glass (105; 306) comprising at least one opening (107; 201, 202, 203; 307) adapted to make said means of electrical connection (104; 304) accessible.

15. A method for manufacturing a device according to claim 12 or 13, comprising the method according to claim 14.

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