Manufacturing Apparatus and Manufacturing Method of Semiconductor Device

Abstract

The present invention provides a manufacturing apparatus for a semiconductor device and a manufacturing method for a semiconductor device, which can further improve the position accuracy of a chip. The manufacturing apparatus for a semiconductor device includes: a stage; two bonding heads that can move independently of each other in the horizontal direction; and a controller that causes the two bonding heads to respectively perform a positioning process of positioning in the horizontal direction, a grounding process of descending until the chip is grounded to the substrate, and a pressing process of applying a load for bonding to the grounded chip. During a non-pressing period in which no bonding head performs the pressing process, the controller causes the two bonding heads to independently perform the positioning process and the grounding process, and causes the two bonding heads that have completed the positioning process and the grounding process to perform the pressing process in parallel.

Description

Technical Field

[0001] This specification discloses a manufacturing apparatus for a semiconductor device having a plurality of bonding heads, and a method for manufacturing a semiconductor device using the manufacturing apparatus. Background Art

[0002] Conventionally, a manufacturing apparatus for a semiconductor device is known, which includes a stage for mounting a substrate and a bonding head for holding a chip, and drives the bonding head to press and bond the chip to the substrate. In the manufacturing apparatus for the semiconductor device, in order to improve the bonding efficiency of the chip, there is a manufacturing apparatus for a semiconductor device provided with a plurality of bonding heads. In a multi-head type manufacturing apparatus, generally, while a part of the bonding heads are performing a pressing process of pressing the chip to the substrate, other bonding heads perform other processes, such as a positioning process for horizontally positioning the bonding head or a grounding process for grounding the chip to the substrate. By adopting the above structure, the standby time of the bonding head can be reduced, and thus the bonding process can be made more efficient.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Laid-Open No. 06-216201

[0006] Patent Document 2: Japanese Patent Laid-Open No. 2002-324821 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] However, when performing a positioning process or a grounding process using other bonding heads while a part of the bonding heads are performing a pressing process, the positional accuracy of the chip may be impaired. That is, in the pressing process, a large load is applied to the stage by the bonding head, and the stage is deflected by the load. And when the stage is deflected, the horizontal position of the electrode provided on the substrate deviates from the original horizontal position. At this time, there is a problem that the accurate horizontal position of the electrode cannot be detected, or even if the bonding head is positioned at the original horizontal position, the relative position between the electrode and the chip still deviates.

[0009] Furthermore, Patent Document 1 discloses a technique: while pressing two film carriers (corresponding to chips) to a display element using two thermocompression bonding elements (corresponding to bonding heads), two other thermocompression bonding elements are grounded to two other film carriers and pressing is started. In the case of this technique, as described above, a positional deviation caused by the deflection of the stage may occur.

[0010] Moreover, Patent Document 2 discloses a technique of simultaneously pressing a plurality of chips using a plurality of crimping tools. However, the crimping tools of Patent Document 2 press the chips that have been temporarily bonded to the substrate in advance, that is, the chips that have been arranged in appropriate positions, and do not mention how to arrange the chips in appropriate positions at all.

[0011] As described above, in the prior art, the positional accuracy of the chips may be degraded due to the flexure of the stage. Therefore, in the present specification, a manufacturing apparatus and a manufacturing method of a semiconductor device that can further improve the positional accuracy of the chips are disclosed.

[0012] Technical means for solving the problem

[0013] The manufacturing apparatus of the semiconductor device disclosed in the present specification is characterized by including: a stage on which a substrate is placed; a plurality of bonding heads each having a bonding tool for holding a chip and movable in the vertical direction and independently movable horizontally; and a controller that causes the plurality of bonding heads to respectively perform a positioning process of positioning in the horizontal direction, a grounding process of descending until the chip is grounded to the substrate or other chips, and a pressing process of applying a load for bonding to the grounded chip. During a non-pressing period in which no bonding head performs the pressing process, the controller causes the plurality of bonding heads to independently perform the positioning process and the grounding process, and causes at least two bonding heads that have completed the positioning process and the grounding process to perform the pressing process in parallel in such a manner that their execution periods at least partially overlap.

[0014] At this time, it is also possible that the controller, after the at least two bonding heads have respectively completed their own grounding processes, maintains the grounded state and waits until the grounding process performed by other bonding heads is completed.

[0015] Moreover, it may further include: a single pick-up unit that sequentially supplies new chips to the plurality of bonding heads, and the controller causes the execution timings of the acceptance processes of the plurality of bonding heads to be staggered so that the execution times of the acceptance processes of accepting new chips by the plurality of bonding heads do not overlap with each other.

[0016] Moreover, it may further include: a plurality of pick-up units respectively provided corresponding to the plurality of bonding heads, which supply new chips to the corresponding bonding heads. The controller causes the plurality of bonding heads to respectively perform the acceptance process of accepting new chips, the positioning process, the grounding process, and the pressing process in parallel with each other, and a predetermined standby time is provided between the grounding process and the pressing process.

[0017] The method for manufacturing a semiconductor device disclosed in this specification manufactures a semiconductor device by bonding a chip to a substrate placed on a stage. The method for manufacturing the semiconductor device is characterized in that it has a bonding tool that holds the chip and can move in the vertical direction, and a plurality of bonding heads that can move horizontally independently of each other respectively perform an acceptance step of accepting a new chip, an alignment step of aligning in the horizontal direction, a grounding step of lowering until the chip touches the substrate or another chip, and a pressing step of applying a load for bonding to the grounded chip. During a non-pressing period in which none of the plurality of bonding heads perform the pressing step, the alignment step and the grounding step are independently performed, and at least two bonding heads that have completed the alignment step and the grounding step perform the pressing step in parallel in such a way that their execution periods at least partially overlap.

[0018] Effects of the Invention

[0019] According to the technology disclosed in this specification, the positional accuracy of the chip can be further improved. Description of the Drawings

[0020] Figure 1 It is a schematic diagram showing the structure of the manufacturing apparatus.

[0021] Figure 2 It is a graph showing the position of the bonding tool and the change in the applied load during the grounding process and the pressing process.

[0022] Figure 3 It is an image diagram showing the situation of the bonding process.

[0023] Figure 4 It is a diagram showing an example of the timing chart of the bonding process.

[0024] Figure 5 It is a diagram showing another example of the timing chart of the bonding process.

[0025] Figure 6 It is a diagram showing another example of the timing chart of the bonding process.

[0026] Figure 7 It is an image diagram showing the situation of the bonding process of the comparative example.

[0027] Figure 8 It is a diagram showing an example of the timing chart of the bonding process of the comparative example.

[0028] Description of Reference Numerals

[0029] 10: Manufacturing apparatus

[0030] 12: Pickup unit

[0031] 14: Bonding head

[0032] 14f: Bonding head (first head)

[0033] 14s: Bonding head (second head)

[0034] 16: Stage

[0035] 18: Controller

[0036] 19: Upper ejector pin

[0037] 20: Pickup head

[0038] 22: XY stage

[0039] 24: Bonding tool

[0040] 26: Head camera

[0041] 28: Processor

[0042] 30: Memory

[0043] 34: Controller

[0044] 100: Semiconductor chip

[0045] 110: Substrate

[0046] 120: Cutting tape

[0047] Fa: Ground load

[0048] Fb: Bonding load

[0049] O: Rotation axis

[0050] t1 to t8, t10 to t17, ta, tb, tc: Moments Detailed implementation manners

[0051] Hereinafter, the structure of the manufacturing apparatus 10 for semiconductor devices will be described with reference to the accompanying drawings. Figure 1 It is a schematic diagram showing the structure of the manufacturing apparatus 10. The manufacturing apparatus 10 manufactures semiconductor devices by bonding a plurality of semiconductor chips 100 to a substrate 110.

[0052] The manufacturing apparatus 10 includes a pick-up unit 12, two bonding heads 14f, 14s, a stage 16, and a controller 18. The pick-up unit 12 has an eject pin 19 that ejects the semiconductor chip 100 placed on a dicing tape 120, and a pick-up head 20 that holds the ejected semiconductor chip 100 with its bottom surface. The pick-up head 20 can rotate about a rotation axis O extending in the horizontal direction. By rotating the pick-up head 20 by 180 degrees, the picked-up semiconductor chip 100 can be inverted by 180 degrees in the thickness direction. Thereby, the surface of the semiconductor chip 100 adhered to the dicing tape 120 faces upward.

[0053] A substrate 110 is placed on the stage 16. Inside the stage 16, a suction mechanism for sucking and holding the substrate 110, a heater for heating the substrate 110, etc. are installed. On the surface of the substrate 110, a plurality of electrodes (not shown) that are electrically and mechanically bonded to the semiconductor chip 100 are formed.

[0054] Above the stage 16, two bonding heads 14f, 14s are provided. Hereinafter, one of the two bonding heads will be referred to as the "first head 14f", and the other will be referred to as the "second head 14s". Moreover, when it is not necessary to distinguish between the two, the suffix letter is omitted and it is referred to as the "bonding head 14".

[0055] The first head 14f and the second head 14s have substantially the same structure, that is, each bonding head 14 is connected to a corresponding XY stage 22 and can move independently of each other in the horizontal direction parallel to the upper surface of the stage 16. Moreover, each bonding head 14 has a bonding tool 24, a lifting mechanism, and a head camera 26. The bonding tool 24 sucks and holds the semiconductor chip 100 and can move in the vertical direction by the lifting mechanism. By lowering the bonding tool 24 toward the substrate 110, the semiconductor chip 100 is grounded to the substrate 110 and pressurized. Also, in the bonding tool 24, a heater for heating the held semiconductor chip 100 is provided.

[0056] The head camera 26 is mounted on the bonding head 14 with its optical axis extending downward, and photographs the substrate 110 etc. placed on the stage 16. The controller 18 calculates the relative positional relationship between the bonding head 14 and the substrate 110 based on the image etc. photographed by the head camera 26, and positions the bonding head 14 based on the calculation result.

[0057] The controller 18 controls the driving of each part of the manufacturing apparatus 10. The controller 18 is a computer physically having a processor 28 and a memory 30. For the "computer", it also includes a microcontroller in which a computer system is incorporated into an integrated circuit. Moreover, the processor 28 refers to a processor in a broad sense, including a general-purpose processor (such as a Central Processing Unit (CPU), etc.) or a dedicated processor (such as a Graphics Processing Unit (GPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a programmable logic element, etc.). Moreover, the operations of the processor 28 described below can be performed not only by one processor but also by multiple processors located at physically separated positions working in cooperation. Similarly, the memory 30 does not have to be a physically single element and may include multiple memories located at physically separated positions. Moreover, the memory 30 may include at least one of a semiconductor memory (such as a Random Access Memory (RAM), a Read Only Memory (ROM), a solid state drive, etc.) and a magnetic disk (such as a hard disk drive, etc.).

[0058] When manufacturing a semiconductor device, bonding terminals (such as bumps, etc., not shown) provided on the bottom surface of the semiconductor chip 100 are bonded to electrodes (not shown) formed on the surface of the substrate 110. In this example, the bonding terminals are bonded to the electrodes of the substrate 110 by Thermal Compression Bonding (TCB) technology. TCB is a technology in which the bonding terminals of the semiconductor chip 100 are pressure-bonded to the electrodes of the substrate 110 at a high pressure under a temperature condition lower than their respective melting points, and original bonding is achieved by means of atomic diffusion generated between the bonding surfaces. In the case of the TCB, the bonding load Fb applied to the semiconductor chip 100 is relatively large, and the time for the pressing process of pressing the semiconductor chip 100 against the substrate 110 using the bonding head 14 is relatively long.

[0059] Here, in this example, in parallel with the pressing process performed by the first head 14f, the pressing process performed by the second head 14s is executed. Moreover, the execution timing of each process of the two bonding heads 14f, 14s is adjusted to avoid a decrease in the positioning accuracy of the other bonding head 14s, 14f due to the pressing process performed by one of the bonding heads 14f, 14s.

[0060] For this, the comparative example and the present example are compared and described below. Figure 2 It is a graph showing the position of the bonding tool 24 and the transition of the applied load during the grounding process and the pressing process. Figure 3 It is an image diagram showing the bonding process of the present example. Figure 4 It is a diagram showing an example of the timing diagram of the bonding process of the present example. Moreover, Figure 7 It is an image diagram showing the bonding process of the comparative example. Figure 8 It is a diagram showing an example of the timing diagram of the bonding process of the comparative example. The comparative example is a process that emphasizes shortening the processing time of the bonding process.

[0061] In the bonding process of bonding the semiconductor chip 100 to the substrate 110, the controller 18 causes each bonding head 14 to sequentially perform an acceptance process, a positioning process, a grounding process, and a pressing process. The acceptance process is a process of accepting a new semiconductor chip 100 from the pickup unit 12. When the acceptance process is completed, the controller 34 performs a positioning process of positioning the bonding tool 24 in the horizontal direction so that the bonding terminals of the semiconductor chip 100 held by the bonding tool 24 are directly above the corresponding electrodes of the substrate 110. In the positioning process, as Figure 3 (a) of Figure 7 (a) of

[0062] shown, the substrate 110 is photographed by the head camera 26, and the horizontal position of the bonding head 14 relative to the substrate 110 is obtained based on the obtained photographed image. Figure 3 (b) of Figure 7 (b) of

[0063] When the positioning process is completed, the controller 34 causes the bonding tool 24 to descend as shown in Figure 2 and performs a grounding process of grounding the semiconductor chip 100 to the substrate 110. And when the grounding process is completed, the controller 34 performs a pressing process of applying a predetermined bonding load Fb to the semiconductor chip 100 using the bonding tool 24. By applying the bonding load Fb, the bonding terminals of the semiconductor chip 100 are bonded to the electrodes of the substrate 110. Furthermore, when applying the load, the substrate 110 and the semiconductor chip 100 can also be heated to a temperature lower than the melting temperature of the electrodes and the bonding terminals using the heaters provided on the stage 16 and the bonding tool 24. Figure 2 The upper part of Figure 2 shows the transition of the Z position of the bonding tool 24 during the grounding process and the pressing process, Figure 2As shown, in the grounding process, the bonding tool 24 is lowered toward the substrate 110. At time ta, when the semiconductor chip 100 starts to contact the substrate 110, the load gradually increases. And when the displacement of the bonding tool 24 stops in a state where a prescribed grounding load Fa is applied to the semiconductor chip 100, it is determined that the grounding is completed. Figure 2 In the example of Figure 2 , at time tb, it is determined that the grounding is completed. If the grounding is completed, the controller 18 drives the lifting mechanism provided in the bonding head 14 and starts the pressing process of applying a prescribed bonding load Fb to the semiconductor chip 1 hundred. When it becomes the time tc after the pressing has elapsed for a fixed time, the controller 34 raises the bonding tool 24 to end the pressing process.

[0064] Here, in this example, two bonding heads 14 are provided, but only one pickup unit 12 is provided. Of course, in this case, it is not possible to perform the receiving process by the first head 14f and the receiving process by the second head 14s in parallel. In this case, if shortening the processing time is prioritized, as long as, as Figure 8 shown in the comparative example, during the execution period t10 to the execution period t11 of the receiving process by the first head 14f, the second head 14s performs a process other than the receiving process (in the example of the figure, the pressing process), and during the execution period t11 to the execution period t12 of the receiving process by the second head 14s, the first head 14f performs a process other than the receiving process (in the example of the figure, the positioning process and the grounding process). If the above structure is adopted, the standby time during which the bonding head 14 does not perform any operation can be eliminated, and thus the time required for manufacturing the semiconductor device can be shortened.

[0065] However, in the structure of the comparative example, it is possible that the positioning accuracy of the other bonding head 14 may decrease due to the pressing process performed by one of the bonding heads 14 That is, in the comparative example, as Figure 8 shown, during the period (t12 to t14) in which the first head 14f is performing the pressing process, the second head 14s is performing the positioning process (hatched area with grids) and the grounding process (hatched area with horizontal lines). In the pressing process, as described above, a relatively large bonding load Fb is applied to the substrate 110 and even the stage 16. As a result, the stage 16 and the substrate 110 may be deflected centering on the pressing portion as Figure 7 shown in (b) of Figure 7 . In a state where the stage 16 is deflected, the horizontal position of the second head 14s with respect to the substrate 110 deviates compared to when the stage 16 is in a horizontal state. Therefore, if the positioning process or the grounding process is performed by the second head 14s in a state where the stage 16 is deflected due to the pressing process of the first head 14f, the semiconductor chip 100 held by the second head 14s cannot be grounded to an appropriate position, resulting in a decrease in the position accuracy of the chip bonding.

[0066] Therefore, in this example, the following structure is adopted: the execution period of the pressing process of the first head 14f is at least partially repeated with the execution period of the pressing process of the second head 14s. On the other hand, the positioning process and the grounding process are permitted only during the non-pressing period when no pressing process is executed on any of the bonding heads 14. That is, as Figure 4 shown, even if the first head 14f has completed the grounding process at time t3, the pressing process is not started but standby until time t4 when the grounding process of the second head 14s is completed. And after time t4 when the grounding process of the second head 14s is completed, the pressing process of the first head 14f is started. In other words, in this example, during the execution period of the pressing process of the first head 14f (t4 to t5), the positioning process and the grounding process of the second head 14s are not executed, and during the execution period of the pressing process of the second head 14s (t4 to t5), the positioning process and the grounding process of the first head 14f are not executed. By adopting the above structure, during the execution period of the positioning process and the grounding process, the flexure of the stage 16 caused by the pressing process will not occur, so the positioning and grounding can be accurately performed, and thus the position accuracy of chip bonding can be improved.

[0067] Moreover, in the case of TCB, the time required for the pressing process is several to more than ten times longer than the time required from the start of the process until the grounding process is completed. Thus, by using multiple bonding heads 14 to perform the pressing process with a long required time in parallel, the standby time of the bonding heads 14 can be shortened, and the increase in the time required for manufacturing the semiconductor device can be suppressed to a small amount. Furthermore, Figure 4 in the example of, the pressing process of the first head 14f and the pressing process of the second head 14s are started simultaneously. However, the start timing of the pressing processes of the two bonding heads 14 does not necessarily need to be simultaneous as long as it is after the grounding processes of both the first head 14f and the second head 14s are completed. That is, as long as the semiconductor chip 100 is once grounded to an appropriate position, even if the flexure of the stage 16 occurs subsequently, it is difficult to cause a position deviation. Therefore, as long as the grounding is performed, even if the pressing process by the other bonding head 14 is started and the flexure of the stage 16 occurs, the problem is small, so the start timing of the pressing processes of the two bonding heads 14 can also be different. However, ideally, the bias of the load applied to the stage 16 is small, so it is ideal to set the start timing of the pressing processes of the two bonding heads 14 to be approximately the same.

[0068] In any case, according to the manufacturing apparatus 10 of the semiconductor device disclosed in this specification, the positional accuracy of the semiconductor chip 100 can be further improved. Furthermore, the structures described so far are examples. As long as the positioning process and the grounding process are performed independently for the plurality of bonding heads 14 during the non-pressurization period in which no pressurization process is performed on any of the bonding heads 14, and at least two bonding heads 14 that have completed the positioning process and the grounding process perform the pressurization process in parallel in such a way that their execution periods at least partially overlap, other structures can also be appropriately changed.

[0069] For example, the number of bonding heads 14 provided in one manufacturing apparatus 10 is not limited to two, and may be a larger number. Figure 5 FIG. is an example of a timing chart when one manufacturing apparatus 10 has three bonding heads 14. Figure 5 In the example of, after the time t2 when the grounding processes for all three bonding heads 14 are completed, the pressurization process for each bonding head 14 is started. And, as Figure 5 shown, the start timing of the pressurization processes for the plurality of bonding heads 14 does not need to be simultaneous and may be offset.

[0070] Moreover, in the above example, only one pickup unit 12 for delivering a new semiconductor chip 100 is provided in the bonding head 14, but the pickup unit 12 may also be provided in the same number as the bonding heads 14. Figure 6 FIG. is an example of a timing chart when two pickup units 12 and two bonding heads 14 are provided. In this case, the pickup unit 12 supplies a new semiconductor chip 100 to the corresponding bonding head 14. In the case of such a structure, the two bonding heads 14 can perform the receiving process in parallel, so that the start timing of the subsequent positioning process, grounding process, and pressurization process can be made substantially the same. However, it is difficult to make the execution times of the respective processes in the plurality of bonding heads 14 exactly the same, and the end timing of the grounding process will deviate slightly. Therefore, as Figure 6 shown, a predetermined standby time (blank portion) can be provided between the grounding process and the pressurization process. By providing the standby time, the deviation in the end timing of the grounding process can be absorbed using the standby time, and each bonding head 14 can advance the process without considering the progress of the other bonding heads 14. As a result, the control of the plurality of bonding heads 14 can be simplified. Moreover, in the above description, the case of bonding the semiconductor chip 100 to the substrate 110 has been described as an example, but the technology disclosed in this specification can also be applied to the case of bonding one semiconductor chip 100 to another semiconductor chip 100.

Claims

1. A manufacturing apparatus for a semiconductor device, characterized in that, Comprising: A stage for placing a substrate; A plurality of bonding heads, each having a bonding tool for holding a chip and capable of moving vertically, and capable of moving horizontally independently of each other; A controller for causing the plurality of bonding heads to respectively perform a positioning process for positioning in the horizontal direction, a grounding process of lowering the chip until it is grounded to the substrate or another chip, and a pressing process of applying a load for bonding to the grounded chip; And A single pick-up unit for sequentially supplying new chips to the plurality of bonding heads, During a non-pressing period when no bonding head is performing the pressing process, the controller causes the plurality of bonding heads to independently perform the positioning process and the grounding process, and causes at least two bonding heads that have completed the positioning process and the grounding process to perform the pressing process in parallel in a manner where at least part of their execution periods overlap, The controller causes the execution timing of the acceptance process of the plurality of bonding heads to be staggered so that the execution times of the acceptance process of accepting new chips by the plurality of bonding heads do not overlap with each other.

2. The manufacturing apparatus for a semiconductor device according to claim 1, wherein After the controller causes each of the at least two bonding heads to complete its own grounding process, it maintains the grounded state and stands by until the grounding process performed by other bonding heads is completed.

3. A manufacturing apparatus for a semiconductor device, characterized in that, Comprising: A stage for placing a substrate; A plurality of bonding heads, each having a bonding tool for holding a chip and capable of moving vertically, and capable of moving horizontally independently of each other; A controller for causing the plurality of bonding heads to respectively perform a positioning process for positioning in the horizontal direction, a grounding process of lowering the chip until it is grounded to the substrate or another chip, and a pressing process of applying a load for bonding to the grounded chip; And A plurality of pick-up units provided corresponding to the plurality of bonding heads respectively, for supplying new chips to the corresponding bonding heads, During a non-pressing period when no bonding head is performing the pressing process, the controller causes the plurality of bonding heads to independently perform the positioning process and the grounding process, and causes at least two bonding heads that have completed the positioning process and the grounding process to perform the pressing process in parallel in a manner where at least part of their execution periods overlap, The controller causes the plurality of bonding heads to respectively perform the acceptance process of accepting new chips, the positioning process, the grounding process, and the pressing process in parallel with each other, and a predetermined standby time is provided between the grounding process and the pressing process to absorb the deviation of the end timing of the grounding process.

4. A method for manufacturing a semiconductor device, in which a chip is bonded to a substrate placed on a stage to manufacture a semiconductor device, characterized in that A plurality of bonding heads each having a bonding tool for holding the chip and capable of moving vertically and capable of moving horizontally independently of each other respectively perform a positioning step of positioning in the horizontal direction, a grounding step of lowering the chip until it is grounded to the substrate or another chip, and a pressing step of applying a load for bonding to the grounded chip. During a non-pressurizing period in which none of the plurality of bonding heads performs the pressurizing step, the positioning step and the grounding step are performed independently of each other. At least two bonding heads that have completed the positioning step and the grounding step perform the pressurizing step in parallel in such a manner that at least part of their execution periods is repeated. The execution timing of the acceptance process is staggered so that the execution times of the acceptance process of accepting new chips by the plurality of bonding heads do not overlap with each other.

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