Die Attach System and Method for Attaching a Die to a Substrate - Patent application

Abstract

To provide an improved system and method for attaching a die to a substrate in conjunction with a practical example that does not utilize pick-and-place operations.SOLUTION: A die attachment system 100 includes a support structure for supporting a substrate 112, a die supply source 108 including a plurality of dies 108a for attachment to the substrate 112, a bond head 104 for bonding a die 108a from the die supply source 108 to the substrate 112, the bond head 104 including a bond tool 104b for contacting the die 108a during a transfer from the die supply source 108 to the substrate 112, a first movement system 102' for moving the bond head 104 along a first axis, and a second movement system 104' independent of the first movement system 102' for moving the bond tool 104b along the first axis.SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 62 / 726,387, filed Sep. 3, 2018, the contents of which are hereby incorporated by reference.

[0002] The present invention relates to a system and method for attaching a die to a substrate, and more particularly to an improved system and method for attaching a die to a substrate without picking the die from a die supply. [Background technology]

[0003] In connection with the placement of die on a substrate (e.g., the placement of semiconductor die on a substrate), many conventional applications utilize a "pick and place" operation. In such an operation, a die is "picked" from a semiconductor wafer or other die source, and then the die is transferred (and "placed") to a target substrate. Such operations also utilize one or more transfers between a "pick" tool and a "place" tool.

[0004] In certain die attachment applications, a pick-and-place operation is not utilized. For example, a die source (e.g., a wafer including multiple dies) may be placed between the bond tool and the substrate. The die included in the die source may be attached to a film or the like. After alignment between the bond tool, the die to be attached, and the placement location of the substrate, the bond tool presses the die against the placement location of the substrate. An adhesive is provided on the underside of the die (and / or at the placement location of the substrate) such that the die is secured to the substrate at this point. Such a bond tool may include multiple pins (e.g., vertically actuable pins) for contacting the die in conjunction with transfer from the die source to the substrate. The prior art documents relevant to the invention of this application are as follows (including documents cited during the international phase after the international filing date and documents cited when the application entered the national phase in other countries). (Prior art document) (Patent Documents) (Patent Document 1) JP 2001-284404 A (Patent Document 2) JP 2017-168693 A (Patent Document 3) U.S. Patent Application Publication No. 2016 / 276205 (Patent Document 4) U.S. Patent Application Publication No. 2012 / 0014084 (Patent Document 5) U.S. Patent No. 10,410,905 Summary of the Invention [Problem to be solved by the invention]

[0005] Such applications (those not using a pick-and-place operation) are prone to problems, such as changes in the alignment of multiple elements (e.g., bond tool, attached die, and substrate placement location), the speed of the die attachment operation, and the associated UPH (i.e., processing time).

[0006] It would therefore be desirable to provide an improved system and method for attaching a die to a substrate, particularly in conjunction with applications that do not utilize a pick-and-place operation. [Means for solving the problem]

[0007] According to an exemplary embodiment of the present invention, there is provided a die attach system having a support structure for supporting a substrate, a die source including a plurality of die for attachment to the substrate, a bond head for bonding die from the die source to the substrate, the bond head including a bond tool for contacting the die during transfer of the die from the die source to the substrate, a first motion system for moving the bond head along a first axis, and a second motion system, independent of the first motion system, for moving the bond tool along the first axis.

[0008] According to another exemplary embodiment of the present invention, there is provided a die attach system having a support structure for supporting a substrate, a die source including a plurality of die for attachment to a substrate, a bond head for bonding die from the die source to the substrate, the bond head including a bond tool for contacting the die during transfer from the die source to the substrate, a first motion system for moving the die source along a first axis, and a second motion system, independent of the first motion system, for moving the die source along the first axis.

[0009] According to yet another exemplary embodiment of the present invention, there is provided a method of attaching a die to a substrate, the method comprising: (a) operating a first motion system to move a bond head along a first axis, the bond head for bonding the die from a die supply to a substrate, the bond head including a bond tool for contacting the die during transfer of the die from the die supply to the substrate, (b) operating a second motion system to move the bond tool along the first axis independent of the first motion system, and (c) operating the bond tool to transfer the die from the die supply to the substrate.

[0010] According to yet another exemplary embodiment of the present invention, there is provided a method of attaching a die to a substrate, the method comprising: (a) operating a first motion system to move a die source along a first axis, (b) operating a second motion system to move the die source along the first axis independent of the first motion system, and (c) operating the bond tool to transfer the die from the die source to the substrate, the bond tool being included as part of a bond head and contacting the die during transfer from the die source to the substrate. [Brief description of the drawings]

[0011] The invention is best understood from the following detailed description when read in conjunction with the accompanying drawings, in which: It is emphasized that, according to common practice, the various features of the drawings are not drawn to scale. It is noted that dimensions of the various features have been arbitrarily expanded or reduced for clarity. [Figure 1A] FIG. 1A is a block plan view of components of a die attach system in accordance with an exemplary embodiment of the present invention. [Figure 1B] FIG. 1B is another block plan view of the components of the die attach system of FIG. 1A. [Fig. 1C-1D] Figure 1C is a block side view of components of the die attach system of Figure 1 A. Figure 1D is a detailed view of an exemplary bond tool of the die attach system of Figure 1 A in accordance with an exemplary embodiment of the present invention. [Figure 2A] 2A-2E are block side views illustrating a die attach operation of the die attach system of FIG. 1A in accordance with an exemplary embodiment of the present invention. [Figure 2B] 2A-2E are block side views illustrating a die attach operation of the die attach system of FIG. 1A in accordance with an exemplary embodiment of the present invention. [Figure 2C]2A-2E are block side views illustrating a die attach operation of the die attach system of FIG. 1A in accordance with an exemplary embodiment of the present invention. [Figure 2D] 2A-2E are block side views illustrating a die attach operation of the die attach system of FIG. 1A in accordance with an exemplary embodiment of the present invention. [Figure 2E] 2A-2E are block side views illustrating a die attach operation of the die attach system of FIG. 1A in accordance with an exemplary embodiment of the present invention. [Figure 3A] 3A-3C are block side views illustrating a die attach operation of the die attach system of FIG. 1A in accordance with another exemplary embodiment of the present invention. [Figure 3B] 3A-3C are block side views illustrating a die attach operation of the die attach system of FIG. 1A in accordance with another exemplary embodiment of the present invention. [Figure 3C] 3A-3C are block side views illustrating a die attach operation of the die attach system of FIG. 1A in accordance with another exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] As used herein, the term "die" is intended to refer to any structure that includes (or is later configured to include) a semiconductor chip or die. Exemplary "die" elements include bare semiconductor die, including bare LED semiconductor die, semiconductor die on a substrate (e.g., lead frames, PCBs, carriers, semiconductor chips, semiconductor wafers, BGA substrates, semiconductor elements, etc.), packaged semiconductor devices, flip chip semiconductor devices, dies embedded in a substrate, etc.

[0013] According to certain exemplary embodiments of the present invention, there is provided a die attachment system including an apparatus of the present invention for supporting a bond head or die source. Such an apparatus includes (i) a long stroke section supporting a short stroke shaft, and (ii) a short stroke section supporting a bond head or die source. For example, the long stroke shaft moves at a constant velocity relative to a substrate (configured to receive a die in a die attach / bonding sequence) during a bonding sequence. The short stroke shaft is stationary relative to the substrate during the bonding operation. After the bonding operation, the short stroke shaft catches up with the long stroke shaft and moves to the next bond position.

[0014] Exemplary components included in the apparatus of the present invention include combinations of: (1) a short, long stroke bond head with a relatively slow single axis die source that uses a method of skipping dies on the source to prevent the slower source axis from limiting the bond rate, (2) a short, long stroke bond head with a short, long stroke die source, and (3) an alternative high speed bonding apparatus (e.g., laser, air pulse) with a short, long stroke die source. Of course, other devices (and associated methods of operation) are contemplated.

[0015] Aspects of the invention relate to combining the advantages of a long stroke axis and a short stroke axis (associated with either or both the bond head and the die source). In a particular embodiment applied to a bond head, the short stroke portion of the motion axis allows for a high bond rate while the long stroke portion allows the bond head to achieve a desired stroke. Exemplary ranges of motion for the short stroke include (i) less than 1 mm, (ii) less than 3 mm, or any desired range of motion.

[0016] 1A illustrates a die attach system 100. The die attach system 100 has a support structure 110 for supporting a substrate 112, a die source 108 including a plurality of dies 108a configured to be attached to the substrate 112, and a bond head 104 including a bond tool 104b for contacting the dies 108a during transfer of the dies 108a from the die source 108 to the substrate 112. The die attach system 100 also includes a bond head support 102 and a supply support 106. The bond head support 102 and the supply support 106 are each independently movable relative to a mechanical structure 150. The bond head support 102 supports a movable bond head 104. The bond head 104 includes a camera 104a (and other vision system components) that is used in connection with alignment and / or inspection operations. The die source 108 is movably mounted on the supply support 106. In the exemplary embodiment of the invention shown in FIG. 1A (and FIGS. 1B-1C), during a die attach operation, a die supply 108 is disposed between a bond tool 104b and a substrate 112 supported by a support structure 110.

[0017] Figure 1B shows the bond head 104 (including camera 104a and bond tool 104b) positioned over die 108a, which is then positioned over a substrate 112. Figure 1C is a cross-sectional view of Figure 1B along line AA, showing the bond head 104, including camera 104a and bond tool 104b, positioned over the substrate 112. Two "bonded" die 108a' are shown bonded to the substrate 112 at their respective bonding locations, and the bond tool 104b is shown engaging another die 108a at a third bonding location on the substrate 112.

[0018] 1D illustrates a block diagram of an example of a bond tool 104b. More specifically, the bond tool 104b may include at least one pin 104b1 for contacting the die 108a for transfer from the die source 108 to the substrate 112. Additionally, as illustrated in FIG. 1D, the bond tool 104b may include multiple pins 104b1 for contacting the die 108a in association with transfer from the die source 108 to the substrate 112. Each of the multiple pins 104b1 may be independently or collectively movable (e.g., along a vertical axis) relative to other portions of the bond tool 104b to transfer the die 108a to the substrate 112.

[0019] The bond tool 104b including one or more pins 104b1 (shown in FIG. 1D) is just one example of a bond tool 104b. In other embodiments of the invention, the bond tool 104b may not include the pins 104b1 and may transfer the die 108a without the pins 104b1.

[0020] According to certain exemplary embodiments of the present invention, at least one of (i) the bond tool 104b and (ii) the die source 108 moves along an axis (e.g., a horizontal axis, or a substantially horizontal axis) using a first motion system and a second motion system. For example, Figures 2A-2E show a first motion system 102' and a second motion system 104' (the operation of which is described in more detail below in connection with Figures 2A-2E). Additionally, Figures 3A-3C show a first motion system 106' and a second motion system 108' (the operation of which is described in more detail below in connection with Figures 3A-3C). It will be understood that the die attachment system 100 illustrated and described herein includes (i) a first motion system and a second motion system for moving the bond tool 104b (as in Figures 2A-2E), (ii) a first motion system and a second motion system for moving the die source 108 (as in Figures 3A-3C), or both (i) and (ii).

[0021] FIG. 2A shows a side cross-sectional view of the die attachment system 100 (described above in connection with FIGS. 1A-1C), but where the bond head 104 includes a first movable carrier 114 and a second movable carrier 116. The first movable carrier 114 is located between the head support 102 and the second movable carrier 116. The second movable carrier 116 is disposed between the first movable carrier 114 and the bond tool 104b. The first motion system 102′ provides linear motion along a first axis (x-axis in FIG. 2A, although other linear axes such as y-axis are contemplated) of the first movable carrier 114 relative to the bond head support 102. The second motion system 104′ provides linear motion along a first axis of the second movable carrier 116 relative to the first movable carrier 114. FIG. 2A also shows a motion system 106′ configured to move the die supply 108 relative to the supply support 106. Each of the motion systems 102', 104', and 106' includes elements (not specifically shown for simplicity) between their adjacent components. For example, the motion system 102' includes motion system elements (e.g., motors, slides, ball screws, bearings, etc.) for providing motion between the first moveable carrier 114 relative to the bond head support 102.

[0022] The exemplary first motion system 102' is included in a gantry system of the die attachment system 100 for moving the bond head 104. The die 108a is positioned over and bonded to a bonding location 112a on a substrate 112. The bond head 104 then moves in a vertical (e.g., z-axis) direction of the double-headed arrow in bonding the bonding die 108a to the bonding location 112a.

[0023] 2B illustrates the movement of the bond head 104 along the bond head support 102 with the first motion system 102' as the bond tool 104b engages the left-most die 108a and bonds the left-most die 108a to the left-most bonding location 112a. As the bond head 104 moves to the right as shown in FIG. 2B, the bond tool 104b uses the second motion system 104' to move left relative to the first movable carrier 114 to stay over the left-most bonding location 112a and bond the left-most die 108a to the left-most bonding location 112a.

[0024] FIG. 2C shows the bond head 104 moving further to the right along the bond head support 102 using the first motion system 102' while the bond tool 104b moves further to the left relative to the first movable carrier 114 using the second motion system 104' to remain over the leftmost bonding position 112a and the bond tool 104b moves upward to its pre-bonding position within the second movable carrier 116.

[0025] 2D illustrates continued rightward movement of the bond head 104 along the bond head support 102 using the first motion system 102' as the bond tool 104b moves rightward relative to the first movable carrier 114 using the second motion system 104' to position the bond tool 104b over the next bond location 112a in preparation for the next bond. The die source 108 (e.g., a wafer such as an LED wafer or other LED die source) using a third motion system 106' moves left relative to the supply support 106. 2E shows the die source 108 moving to the right relative to the substrate 112 using the motion system 106' so that the remaining left-most die 108a is above the next bond location 112a and below the bond tool 104b. The process continues as in FIGS. 2A-2E, bonding the left-most die 108a to the next bond location 112a, then resetting to bond the next remaining left-most die 108a (or other die 108a, if desired) to the next bond location 112a.

[0026] FIG 3A shows a further embodiment of the invention in which there is a single motion system 102' for the bond head 104 (including the movable carrier). In FIG 3A (and FIGS 3B-3C), the supply support 106 (for supporting the die source 108m) includes the support 118, the first motion system 106', the movable carrier 120 (for carrying the die source 108, such as an LED wafer or other LED die source), and at least a portion of the second motion system 108'. The bond tool 104b (shown as a vertical dashed line below the bond head 104) is positioned above the leftmost bond die 108a and the leftmost bond position 112a.

[0027] The first motion system 106' provides linear motion along a first axis (x-axis in FIG. 3A , although other linear axes such as y-axis are contemplated) of the moveable carrier 120 relative to the support 118. The second motion system 108' provides linear motion of the die source 118 along the first axis relative to the moveable carrier 120. Each of the motion systems 102', 106', and 108' includes elements (not specifically shown for simplicity) between their adjacent components. For example, the motion system 106' includes motion system elements (e.g., motors, slides, ball screws, bearings, etc.) for providing motion between the moveable carrier 120 and the support 118.

[0028] FIG. 3B illustrates bonding of the left-most bonding die 108a to the left-most bonding location 112a as the movable carrier 120 moves to the right and the die source 108 moves to the left relative to the movable carrier 120 and remains stationary relative to the bond tool as a bond is formed between the left-most bonding die 108a and the left-most bonding location 112a.

[0029] 3C shows after the first bond and movement of the bond head 104 to the right to position the bond tool over the next bond location 112a, with the die source 108 also moving rightward as the fourth movable carrier 120 moves to the right to align the bond tool over the now leftmost bond die 108a on the die source 108 over the next bond location 112a. The process continues as in FIGS. 1 and 2 for the next bond.

[0030] As shown in the various figures, double-headed arrows are intended to indicate movement (or potential movement through a motion system) of an associated element.

[0031] Exemplary embodiments of the present invention tend to provide substantially higher bond rates without compromising precision.

[0032] Although not explicitly shown in the drawings, the present invention contemplates embodiments in which the bond head and die source each include multiple motion systems. For example, a die attachment system within the scope of the present invention may include first and second motion systems for moving the bond tool (e.g., FIGS. 2A-2E) along with first and second motion systems for moving the die source (e.g., FIGS. 3A-3C).

[0033] The present invention has been described primarily, but not exclusively, in the context of die attach operations without a "pick" operation. The present invention has broad application in the semiconductor bonding industry, including die attach machines (sometimes called die bonders) or other packaging machines (e.g., flip chip equipment / operations, advanced packaging operations, etc.).

[0034] While the invention has been described and illustrated with respect to exemplary embodiments thereof, it will be understood by those skilled in the art that the foregoing and various other modifications, omissions, and additions may be made thereto without departing from the spirit and scope of the invention. Rather, various modifications in the details may be made within the scope and range of equivalents of the claims without departing from the invention.

Claims

1. 1. A die attach system comprising: a support structure for supporting the substrate; a die source including a plurality of dies for attachment to the substrate; a bond head for bonding a die from the die source to the substrate, the bond head including a bond tool for contacting the die during transfer of the die from the die source to the substrate without a pick operation; a first motion system for moving the die supply along a first axis; a second motion system, independent of the first motion system, for moving the die supply along the first axis; having during movement of the die source in a first direction along the first axis, the second motion system selectively moves the die source in a second direction along the first axis, the second direction being opposite to the first direction such that the die source remains stationary relative to the bond tool during transfer of the die from the die source to the substrate. Die Attach System.

2. 2. The die attach system of claim 1, A die attach system, wherein the bond tool includes at least one pin for contacting the die in association with transfer of the die from the die source to the substrate.

3. 2. The die attach system of claim 1, The bond tool includes a plurality of pins for contacting the die in association with transfer of the die from the die source to the substrate.

4. 2. The die attach system of claim 1, The die attach system, wherein the die source comprises an LED wafer and the plurality of dies is a plurality of LED dies.

5. 2. The die attach system of claim 1, 11. A die attachment system, comprising: (i) the die; and (ii) at least one of the bonding locations of the substrate configured to receive the die, the bonding location including an adhesive for securing the die at the bonding location after transfer from the die source to the substrate.

6. 2. The die attach system of claim 1, The first axis is an x-axis or a y-axis of the die attach system.

7. 2. The die attach system of claim 1, The die attach system, wherein the die supply is configured to be positioned between the substrate and the bond tool during a bonding operation.

8. 1. A method for attaching a die to a substrate, comprising the steps of: (a) operating a first motion system to move a die supply along a first axis; (b) operating a second motion system to move the die supply along the first axis independently of the first motion system; (c) transferring the die from the die source to the substrate by operating a bond tool, the bond tool being included as part of a bond head and contacting the die during transfer from the die source to the substrate without a pick operation; having during movement of the die source in a first direction along the first axis, the second motion system selectively moves the die source in a second direction along the first axis, the second direction being opposite to the first direction such that the die source remains stationary relative to the bond tool during transfer of the die from the die source to the substrate. method.

9. 9. The method of claim 8, wherein the bond tool includes at least one pin for contacting the die in connection with its transfer from the die source to the substrate in step (c).

10. 9. The method of claim 8, The method, wherein the bond tool includes a plurality of pins for contacting the die in association with transfer of the die from the die source to the substrate.

11. 9. The method of claim 8, The method, wherein the die source comprises an LED wafer comprising a plurality of LED dies.

12. 9. The method of claim 8, at least one of (i) the die and (ii) a bonding location of the substrate configured to receive the die includes an adhesive for securing the die at the bonding location after transfer from the die source to the substrate.

13. 9. The method of claim 8, The method, wherein the first axis is an x-axis or a y-axis of a die attach system.

14. 9. The method of claim 8, The method, wherein the die supply is configured to be positioned between the substrate and the bond tool during a bonding operation.

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