CONNECTOR

Abstract

The present disclosure relates to an electronic device comprising a wafer comprising a first upper surface having at least one first contact arranged thereon; and at least one die comprising a second upper surface having at least one second contact arranged thereon, and at least one first lateral surface orthogonal to the second upper surface, said first contact being coupled to said second contact by a connector comprising one first conductive pillar formed on said first contact of said wafer; one second conductive pillar formed on said second contact of said die; and at least one conductive ball positioned in contact with at least a first upper portion of said first pillar(s) and in contact with at least one second upper portion of said second pillar(s).

Claims

1. A method, comprising: forming a first number of first electrically-conductive pillars on a first contact on a surface of a substrate; forming a second number of second electrically-conductive pillars on a second contact on a contact surface of the die; coupling a lateral surface of a die transverse to the contact surface of the die to the surface of the substrate by an adhesive; and forming an electrically-conductive ball coupling the first number of first electrically conductive pillars to the second number of the second electrically conductive pillar.

2. The method according to claim 1, wherein the first number is different from the second number.

3. The method according to claim 1, wherein the first number is equal to the second number.

4. The method according to claim 1, wherein coupling the lateral surface of the die transverse to the contact surface of the die to a surface of the substrate by an adhesive further includes offsetting the die from the first contact on the surface of the substrate.

5. The method according to claim 1, wherein coupling the lateral surface of the die transverse to the contact surface of the die to the surface of the substrate by the adhesive further includes aligning the first number of the first electrically-conductive pillars with the second number of the second electrically conductive pillars.

6. A method, comprising: forming a first number of first electrically-conductive pillars on a first contact on a surface of the substrate; forming a second number of second electrically-conductive pillars on a second contact on the surface of the substrate; forming a third number of third electrically-conductive pillars on a third contact on a contact surface of a die; forming a fourth number of fourth electrically-conductive pillars on a fourth contact on the contact surface of the die; coupling a lateral surface of the die transverse to the contact surface of the die to the surface of the substrate by an adhesive; forming a first electrically-conductive ball coupling the first number of the first electrically-conductive pillars to the third number of the third electrically-conductive pillars; and forming a second electrically-conductive ball coupling the second number of the second electrically-conductive pillars to the fourth number of the fourth electrically-conductive pillars.

7. The method according to claim 6, wherein coupling the lateral surface of the die transverse to the contact surface of the die to the surface of the substrate by the adhesive further includes: aligning the first number of the first electrically-conductive pillars with the third number of the third electrically-conductive pillars; and aligning the second number of the second electrically-conductive pillars with the fourth number of the fourth electrically-conductive pillars.

8. The method of claim 6, wherein: the first number of the first electrically-conductive pillars is at least two; the third number of the third electrically-conductive pillars is at least one.

9. The method of claim the method of claim 8, wherein: the second number of the second electrically-conductive pillars is at least one; and the fourth number of the fourth electrically-conductive pillars is at least one.

10. The method of claim 8, wherein: the second number of the second electrically-conductive pillars is at least two; and the fourth number of the fourth-electrically conductive pillars is at least two.

11. The method of claim 6, wherein the forming the first number of the first electrically-conductive pillars, forming the second number of the second electrically-conductive pillars, forming the third number of the third electrically-conductive pillars, and forming the fourth number of the fourth.

12. The method of claim 6, wherein the lateral surface is transverse to the contact surface of the die.

13. A method, comprising: forming a first die including: a lower surface; an upper surface opposite to the lower surface and facing away from the lower surface; a first lateral surface transverse to the lower surface and the upper surface, the first lateral surface extending from the lower surface to the upper surface; a second lateral surface transverse to the lower surface and the upper surface, the second lateral surface is opposite to the first lateral surface and faces away from the first lateral surface, and the second lateral surface extending from the lower surface to the upper surface; a connection area at the upper surface, the connection area including a first contact at the upper surface; forming one or more first conductive pillars on the first contact of the first die that extend in a first direction; coupling the first lateral surface of the first die to a surface of a wafer with an adhesive at a region offset from a first contact at the surface of the wafer; forming one or more second conductive pillars on the first contact that extend in a second direction transverse to the second contact; and coupling the one or more first conductive pillars and the one or more second conductive pillars to each other by forming a first conductive ball coupling the one or more first conductive pillars to the one or more second conductive pillars.

14. The method of claim 13, wherein: the first die further includes a second contact spaced apart from the first contact; the wafer further includes a second contact at the surface of the wafer space apart from the first contact at the surface of the wafer.

15. The method of claim 14, further comprising forming a second connector coupling the second contact of the first die to the second contact at the surface of the wafer, forming the second connector including: forming one or more third conductive pillars on the second contact of the first die; forming one or more fourth conductive pillars on the second contact at the surface of the wafer; and coupling the one or more third conductive pillars to the one or more fourth conductive pillars to each other by forming a second conductive ball coupling the one or more third conductive pillars to the one or more fourth conductive pillars.

16. The method of claim 15, wherein the one or more second conductive pillars includes at least two second conductive pillar.

17. The method of claim 13, wherein the one or more second conductive pillars includes at least two second conductive pillars.

18. The method of claim 13, wherein forming the one or more first conductive pillars on the first contact of the first die that extend in a first direction occurs before coupling the first die to the surface of the wafer with the adhesive.

19. The method of claim 13, wherein coupling the one or more first conductive pillars to the one or more second conductive pillars occurs after coupling the first die to the surface of the wafer with the adhesive.

20. The method of claim 13, wherein the one or more second conductive pillars are formed before coupling the first die to the surface of the wafer with the adhesive.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0031] The foregoing features and advantages, as well as others, will be described in detail in the following description of specific embodiments given by way of illustration and not limitation with reference to the accompanying drawings, in which:

[0032] FIG. 1 shows a side view of a die;

[0033] FIG. 2 shows a side view of an embodiment of an electronic device; and

[0034] FIG. 3 shows a block diagram illustrating a method of manufacturing the embodiment of FIG. 2.

DETAILED DESCRIPTION

[0035] Like features have been designated by like references in the various figures. In particular, the structural and/or functional features that are common among the various embodiments may have the same references and may dispose identical structural, dimensional and material properties.

[0036] For the sake of clarity, only the steps and elements that are useful for an understanding of the embodiments described herein have been illustrated and described in detail.

[0037] Unless indicated otherwise, when reference is made to two elements connected together, this signifies a direct connection without any intermediate elements other than conductors, and when reference is made to two elements coupled together, this signifies that these two elements can be connected or they can be coupled via one or more other elements.

[0038] In the following disclosure, unless otherwise specified, when reference is made to absolute positional qualifiers, such as the terms front, back, top, bottom, left, right, etc., or to relative positional qualifiers, such as the terms above, below, upper, lower, etc., or to qualifiers of orientation, such as horizontal, vertical, etc., reference is made to the orientation shown in the figures.

[0039] Unless specified otherwise, the expressions around, approximately, substantially and in the order of signify within 10%, and preferably within 5%.

[0040] FIG. 1 is a side view of an electronic die 10 to which the embodiment described as an example in relation with FIG. 2 may be applied.

[0041] Electronic die 10 for example substantially has the shape of a cuboid, and comprises an upper surface 11, a lower surface 12 parallel to upper surface 11, and lateral surfaces 13 and 14 orthogonal to the upper and lower surfaces 11 and 12. In FIG. 1, lateral surface 13 is on the left-hand side of the drawing, and lateral surface 14 is on the right-hand side of the drawing.

[0042] Electronic die 10 comprises at its upper surface level a connection area 15 having contacts 16 of die 10 formed thereon. Contacts 16 are shown in relief in FIG. 1, but as a variant, contacts 16 might not protrude from area 15. For example, the contacts 16 may instead may have end surfaces that are flush with the connection area 15 or may be slightly recessed within the connection area 15. A surface at which the contacts 16 are present on the die 13 may be referred to as a contact surface, a connection surface, or some other similar or like type reference to the respective surface of the die 13 at which the contacts 16 are present.

[0043] Electronic die 10 is, for example, formed of one or a plurality of electronic components protected by a packaging material giving its shape to die 10. For example, the one or the plurality of electronic components may be within a resin giving shape to the die 10.

[0044] A specificity of electronic die 10 is that its lateral surface 13 is its main surface. Main surface here designates the active surface of the electronic die which should be visibly and/or accessibly placed on assembly of electronic die 10 on a printed circuit board or on a substrate plate. In other words, die 10 should be directed along a direction represented by an arrow F1 parallel to upper surface 15, and having its main surface facing direction F1. According to an example, lateral surface 13 comprises an active area of a sensor, an area of emission of a beam, for example, of a laser beam, a display area, etc. According to at least one embodiment, die 10 is an edge emitting laser die, which emits a laser beam at the level of one or its edge, such as lateral surface 13 in FIG. 1. More particularly, the laser beam is emitted from the superior side of the lateral surface 13, as an example at the level of the arrow representing direction F1.

[0045] FIG. 2 is a side view of an embodiment of an electric device 100 comprising the die 10 described in relation with FIG. 1 assembled on a wafer 20.

[0046] Wafer 20 is, for example, a printed circuit board (PCB), or a substrate plate, comprising an upper surface 21 having at least one contact 22 formed thereon. Contact 22 is shown in relief in FIG. 2, but as a variant, contact 22 might not protrude from wafer 20. For example, the contact 22 may instead may have end surfaces that are flush with the upper surface 21 of the wafer 20 or may be slightly recessed within the upper surface 21 of the wafer 20.

[0047] According to an embodiment, die 10 is assembled on wafer 20 by bonding of the lateral surface 14 of die 10 to the upper surface of wafer 20. Thereby, the surface 13 of die 10 is parallel to surface 21 and is oriented upwards in FIG. 2, as indicated by arrow F1. Further, thereby, the upper surface 11 of die 10 is orthogonal or transverse to the upper surface 21 of wafer 20. An example of a method of manufacturing device 100 is described in further detail in relation with FIG. 3.

[0048] Die 10 is electrically coupled to wafer 20 by a connector 30 surrounded and encircled with dotted lines in FIG. 1. More particularly, a contact 16 of die 10 is electrically coupled to a contact 22 of wafer 20 by connector 30. Connector 30 comprises: [0049] one or a stack of a plurality of pillars 31 made of an electrically-conductive material formed on contact 16 and extending along a direction orthogonal or transverse to the upper surface 11 of die 10, in other words parallel to the lateral surface 13 of die 10; [0050] one or a stack of a plurality of pillars 32 made of an electrically-conductive material formed on contact 22 and extending along a direction orthogonal or transverse to the upper surface 21 of wafer 20; and [0051] a ball 33 made of an electrically-conductive material in contact with an upper portion of the last pillar 31 and in contact with an upper portion of the last pillar 32.

[0052] Pillars 31 and 32 are, for example, metal pillars, which may be, for example, made of copper or of a metal alloy comprising copper. The number of pillars 31 and 32 used to form connector 30 is determined by the placing of contacts 16 and 22 on the respective upper surfaces of die 10 and of wafer 20. Thus, a stack of pillars enables to adjust the height, in the direction of arrow F1, and the width, in the direction orthogonal or transverse to the direction of arrow F1, of connector 30. Here call last pillar 31 or last pillar 32 the pillar 31 or 32 when there is a single pillar 31 or 32, or the last pillar 31 or 32. According to an example, in FIG. 2, a single pillar 31 is shown, and a stack of two pillars 32 is shown. However, it will be readily appreciated that different numbers of pillars may be utilized to form electrical connections depending on the size and shape of the die 10 and the size and shape of the wafer 20, or the positioning of the die 10 relative to the contact 22 of the wafer 20.

[0053] Ball 33 enables to electrically connect the last pillar 31 to the last pillar 32. According to an embodiment, ball 33 is a solder ball or soldering paste. Ball 33 is for example made of metal or of a metal alloy, for example, of a metal alloy comprising tin, as an alloy comprising tin, silver, and copper. An advantage of the use of a connector of the type of connector 30 is that such a connector enables to electrically couple electric contacts arranged on surfaces orthogonal to one another. Such a connection cannot be implemented by a wireless solder technique.

[0054] FIG. 3 is a block diagram illustrating the steps of an implementation mode of a method of manufacturing the device 100 described in relation with FIG. 2.

[0055] The manufacturing method comprises three phases, a phase of manufacturing and preparation of die 10, a phase of manufacturing and preparation of wafer 20, and a phase of assembly of die 10 and of wafer 20. The phases of manufacturing and of preparation of die 10 and of wafer 20 may be carried out in parallel, for example, simultaneously or, as a variant, may be carried out one after the other, with no preferred order.

[0056] The phase of manufacturing and of preparation of die 10 comprises the following successive steps: [0057] a step 10-A (PREP DIE) of manufacturing of die 10 during which die 10 and, more particularly, the contacts 16 of die 10, are formed on the upper surface 11 of die 10; [0058] a step 10-B1 (TAPE) or a step 10-B2 (WAFER LEVEL) of placing of die 10; and [0059] a step 10-C (BUMP) of forming of pillar(s) 31 on the contacts 16 of die 10.

[0060] Step 10-A of manufacturing of die 10 comprises the usual die manufacturing steps and more particularly comprises at least one step of manufacturing of contacts 16.

[0061] During steps 10-B1 and 10-B2, die 10 is placed in such a way as to be able to carry out step 10-C. More particularly, during step 10-B1, die 10 is arranged on an adhesive tape band, its upper surface being accessibly positioned, for example, by being directed upwards, as in the position illustrated in FIG. 1. Step 10-B1 may be replaced with step 10-B2 wherein the die has already been individualized, then positioned, for example on an adhesive tape band, being accessibly positioned.

[0062] During step 10-C, the pillar(s) 31 are formed on the contacts 16 of die 10. According to an embodiment, each pillar 31 is formed by using a wireless solder technique. More precisely, the tool used to implement the wireless solder technique forms a metal ball and crushes it on contact 16 and breaks the rest of the metal wire to form pillar 31. This operation may be performed several times to form a stack of pillars 31. For example, in some embodiments, the pillars 31 may be stud bumps that are formed one after the other in succession to form a stacked configured.

[0063] The phase of manufacturing and of preparation of wafer 20 comprises the following successive steps: [0064] a step 20-A (PREP SUBSTRATE) of manufacturing of wafer 20 during which wafer 20 and, more particularly, the contacts 22 of wafer 20 are formed on the upper surface 21 of wafer 20; [0065] a step 20-B (TAPE) of placing of the die; and [0066] a step 20-C (BUMP) of forming of pillar(s) 32 on the contacts 22 of the wafer.

[0067] The step 20-A of manufacturing of wafer 20 comprises usual wafer manufacturing steps and more particularly comprises at least one step of manufacturing of contacts 22.

[0068] During step 20-B, wafer 20 is placed in such a way as to be able to carry out step 20-C. More particularly, wafer 20 is for example arranged on an adhesive tape band, its upper surface 21 being accessibly positioned, for example, by being directed upwards, as in the position illustrated in FIG. 2.

[0069] During step 20-C, pillars 32 are formed on the contacts 22 of wafer 20. According to an embodiment, pillars 32 are formed by using the same technique as that described in relation with step 10-C, that is, a wireless solder technique. More precisely, the tool used to implement the wireless solder technique forms a metal ball and crushes it on contact 22 and breaks the rest of the metal wire to form pillar 32. This operation may be performed several times to form a stack of pillars 32. For example, in some embodiments, the pillars 32 may be stud bumps that are formed one after the other in succession to form a stacked configured.

[0070] The phase of manufacturing of device 100 comprises the following successive steps: [0071] a step 100-A (FIX) where die 10 is mounted on wafer 20; and [0072] a step 100-B (SOLDER J) where connector 30 is completed.

[0073] During step 100-A, the lateral surface 14 of die 10 is bonded to the upper surface 21 of wafer 20, so that the lateral surface 13 of the die is accessible, as illustrated in FIG. 2. According to an example, the lateral surface 14 is bonded by using a gluing method. For example the lateral surface 14 is bonded or coupled to the surface 21 of the wafer 20 by an adhesive 23, which may be a die attach film (DAF), die attach glue, a die attach adhesive, or some other suitable type of adhesive that may be utilized to bond or couple the lateral surface 14 of the die 10 to the surface 21 of the wafer 20.

[0074] During step 100-B, an electrically-conductive ball, for example, a soldering paste ball, is arranged in contact with an upper portion of the last pillar 31 and an upper portion of the last pillar 32 to form ball 33. This operation may be performed by using current solder methods.

[0075] Electronic device (100) may be summarized as including a wafer (20) including a first upper surface (21) having at least one first contact (22) arranged thereon; and at least one die (10) including a second upper surface (11) having at least one second contact (16) arranged thereon, and at least one first lateral surface (14) orthogonal to the second upper surface (11), the first lateral surface (14) of said die (10) being bonded to said first upper surface (21) of said wafer (20), said first contact (22) being electrically coupled to said second contact (16) by a connector (30) including one or a stack of a plurality of first electrically-conductive pillars (32) formed on said first contact (22) of said wafer (20); one or a stack of a plurality of second electrically-conductive pillars (31) formed on said second contact (16) of said die (10); and at least one electrically-conductive ball (33) positioned in contact with at least a first upper portion of said first pillar(s) (32) and in contact with at least one second upper portion of said second pillar(s) (31).

[0076] Method of manufacturing an electronic device (100) may be summarized as including the following successive steps: a) forming (20-C) one or a stack of first electrically-conductive pillars (32) on a first contact (22) formed on a first upper surface (21) of a wafer (20); b) forming (10-C) one or a stack of second electrically-conductive pillars (31) on a second contact (16) formed on a second upper surface (11) of a die (10); c) (100-A) bonding a first lateral surface (14) of said die (10) to the first upper surface (21) of said wafer (20), said first lateral surface (14) being orthogonal to the second upper surface (11) of said die (10); d) forming and arranging an electrically-conductive ball (33) in contact with a first upper portion of said first pillar(s) (32) and in contact with a second upper portion of said second pillar(s) (31).

[0077] Said first pillar(s) (32) may be formed by using a tool adapted to a wireless solder technique.

[0078] Said second pillar(s) (31) may be formed by using a tool adapted to the wireless solder technique.

[0079] Said first pillar(s) (32) may be made of a metal or of a metal alloy.

[0080] Said first pillar(s) (32) may be made of copper or of a metal alloy comprising copper.

[0081] Said second pillar(s) (31) may be made of a metal or of a metal alloy.

[0082] Said second pillar(s) (31) may be made of copper or of a metal alloy comprising copper.

[0083] Said ball (33) may be made of a metal or of a metal alloy.

[0084] Said ball (33) may be a soldering paste ball.

[0085] The first lateral surface (14) of said die (10) may be bonded to the first upper surface (21) of said wafer (20) by gluing.

[0086] Said die (10) may be an edge emitting laser die.

[0087] Said wafer (20) may be a substrate.

[0088] Said wafer (20) may be a printed circuit board.

[0089] Various embodiments and variants have been described. Those skilled in the art will understand that certain features of these various embodiments and variants may be combined, and other variants will occur to those skilled in the art.

[0090] Finally, the practical implementation of the described embodiments and variations is within the abilities of those skilled in the art based on the functional indications given hereabove.