Chip mounting apparatus and method of manufacturing semiconductor device

Abstract

The present application provides a kind of to further reduce the technology of stress applied to bare chip.The chip mounting device has push unit, the head with chuck that adsorbs bare chip, and control part.The control part is configured to use dome plate to adsorb cutting tape, using the head to land the chuck to the bare chip, using the chuck to adsorb the bare chip, from the dome plate, multiple blocks are raised, the outermost peripheral block in the multiple blocks is stopped rising at the height that the bare chip is peeled from the cutting tape, and the blocks outside the outermost peripheral block in the multiple blocks are further raised to a specified height.

Description

Technical Field

[0001] This disclosure relates to chip mounting apparatus, such as a chip mounting machine with a push-up unit. Background Technology

[0002] In a chip mounting machine that mounts semiconductor chips, referred to as bare chips, onto the surface of a wiring substrate or lead frame (hereinafter collectively referred to as a substrate), the following actions (operations) are typically performed repeatedly: the bare chip is transported onto the substrate using suction nozzles such as chucks, pressure is applied, and bonding materials are heated, thereby performing the mounting.

[0003] In the chip mounting process using chip mounting equipment such as chip mounters, there is a stripping process that peels off bare chips separated from semiconductor wafers (hereinafter referred to as wafers). In the stripping process, the bare chips are pushed up from the back of the dicing tape using an up-pushing unit, and peeled off one by one from the dicing tape held by the bare chip supply unit, and transported onto the substrate using suction nozzles such as collets.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: JP 2020-161534 Summary of the Invention

[0007] In recent years, the emergence of chip stacking and 3D-NAND (three-dimensional NAND flash memory) has made wafers (bare dies) thinner. As bare dies become thinner, their rigidity becomes extremely low compared to the adhesion of the dicing tape. Therefore, for example, to pick up thin bare dies of tens of μm or less, it is necessary to further reduce the stress applied to the bare die (stress reduction).

[0008] The subject of this disclosure is to provide a technique for further reducing the stress applied to a bare chip.

[0009] Other issues and new features become clear from the description in the instruction manual and the addition of accompanying drawings.

[0010] If we were to briefly summarize a representative summary of this disclosure, it would be as follows.

[0011] That is, the chip mounting apparatus includes a push-up unit, a head with a collet for adsorbing bare chips, and a control unit. The control unit is configured to use a dome plate to adsorb the dicing tape, use the head to drop the collet onto the bare chip, use the collet to adsorb the bare chip, raise multiple blocks from the dome plate, and stop rising at the height at which the bare chip is peeled off from the dicing tape, and raise the blocks other than the outermost block to a predetermined height.

[0012] Invention Effects

[0013] According to this disclosure, the stress applied to the bare chip can be further reduced. Attached Figure Description

[0014] Figure 1 This is a schematic diagram showing the configuration of the chip mounting apparatus in the embodiment.

[0015] Figure 2 yes Figure 1 The main cross-sectional view of the push-up unit is shown.

[0016] Figure 3 yes Figure 2 The top view of the push-up unit is shown.

[0017] Figure 4 This diagram illustrates the problem points when pushing the block up.

[0018] Figure 5 This is a diagram illustrating the block-pushing action in the implementation method.

[0019] Figure 6 This is a diagram illustrating the push-up sequence of RMS in the implementation method.

[0020] Figure 7 This diagram illustrates the problem points when pushing the block up.

[0021] Figure 8 This is a partial sectional view of the upward push element in the first modified example.

[0022] Figure 9 yes Figure 8 The top view of the push-up unit is shown.

[0023] Figure 10 This is a diagram illustrating the pushing action of the block in the first variation.

[0024] Figure 11 This is a diagram illustrating the structure and operation of the push-up unit in the second variation.

[0025] Figure 12 This is a diagram illustrating the structure and operation of the push-up unit in the second variation.

[0026] Figure 13 This is a diagram illustrating the structure and operation of the push-up unit in the second variation.

[0027] Figure 14 This is a top view of the main part of the push-up unit in the third variation.

[0028] Figure 15 This is a top view of the main part of the push-up element in the fourth variation.

[0029] Figure 16 This is a conceptual diagram of the chip mounting machine in the embodiment, viewed from above.

[0030] Figure 17 This means that in Figure 16 The diagram shows the actions of the pickup head and the mounting head when viewed from the direction of arrow A.

[0031] Figure 18 It is shown Figure 16 A schematic cross-sectional view of the main part of the bare chip supply section is shown.

[0032] Figure 19 It is used to explain its use. Figure 16 The flowchart shown illustrates a method for manufacturing semiconductor devices using a chip mounting machine.

[0033] The reference numerals in the attached figures are explained as follows:

[0034] 100 Chip Mounting Equipment

[0035] BH head

[0036] BL1, the first piece (the outermost piece)

[0037] BL2, the second piece (the inner piece)

[0038] BL3, third piece (inner piece)

[0039] BL4, fourth piece (inner piece)

[0040] BLK block

[0041] CLT collet

[0042] CNT Control Department

[0043] D bare chip

[0044] DP dome plate

[0045] DT cutting belt

[0046] TU push-up unit Detailed Implementation

[0047] Hereinafter, embodiments, modifications, and examples will be described using the accompanying drawings. However, in the following description, the same reference numerals will be used to refer to the same constituent elements, and repeated descriptions will sometimes be omitted. Furthermore, in order to make the description clearer, the drawings may sometimes schematically show the width, thickness, shape, etc. of each part compared to the actual form, but this is only an example and does not limit the interpretation of this disclosure.

[0048] <Implementation Method>

[0049] First, use Figure 1 The chip mounting apparatus described in the embodiment is explained. Figure 1 This is a schematic diagram showing the configuration of the chip mounting apparatus in the embodiment.

[0050] The chip placement apparatus 100 in this embodiment includes a control unit (control device) CNT, which has a main controller 81a, a work controller 81b, a monitor 83a, a touch panel 83b, and a buzzer 83g. The chip placement apparatus 100 also includes an XY stage 86a, a Z drive unit 86b, and a push unit TU controlled by the work controller 81b. The chip placement apparatus 100 also includes a head (placement head or pick-up head) BH that moves up and down using the Z drive unit 86b, and a collet CLT located at the front end of the head BH. The chip placement apparatus 100 also includes a sensor 87a for detecting the position of the push unit TU, a sensor 87b for detecting pressure and flow rate, and a sensor 87c for detecting the gas flow rate of the collet CLT. The push unit TU has the function of vacuum adsorption of the cutting tape and the function of blowing air onto the cutting tape.

[0051] Next, use Figure 2 as well as Figure 3 Explanation of the push-up unit TU. Figure 2 for Figure 1 The cross-sectional view of the push-up unit shown illustrates its contact with the cutting strip. Figure 3 yes Figure 2 The top view of the push-up unit is shown.

[0052] The dome plate DP located on the periphery of the upper surface of the push unit TU is provided with multiple suction ports DPa and multiple slots DPb connecting the multiple suction ports DPa. When the push unit TU is raised and its upper surface contacts the back of the cutting strip DT, the suction port DPa is depressurized by a suction mechanism (not shown). At this time, the back of the cutting strip DT is attracted from below and pressed tightly against the upper surface of the dome plate DP.

[0053] Four blocks BL1 to BL4, which push the cutting strip DT upwards, are assembled at the center of the pushing unit TU. The three outer blocks BL1 to BL3 are cylindrical, and the innermost block BL4 is columnar. Inside the first block BL1, which has the longest outer perimeter, is a second block BL2, which has a shorter outer perimeter than BL1; inside the second block BL2, which has a shorter outer perimeter than BL3; and inside the third block BL3, the fourth block BL4, which has the shortest outer perimeter.

[0054] Of the four blocks BL1 to BL4, the outermost block BL1, with the longest outer perimeter, has a perimeter that is slightly shorter than the bare chip D to be peeled. Therefore, the corner of the upper surface of block BL1, which forms the outer perimeter, is slightly inward compared to the outer edge of the bare chip D. This allows the force for peeling the bare chip D and the dicing tape DT to be concentrated at the starting point of the peeling process (the outermost perimeter of the bare chip D). Here, as... Figure 2 As shown in the dashed circle A, the portion of the bare chip D that protrudes outward from the outermost end of the outermost block BL1 is called the overhang (OH). The length of the overhang is preferably equal to or greater than the thickness of the cutting strip DT.

[0055] The thickness of the cutting strip DT is, for example, about 0.1 mm. The length of the protrusion is, for example, about 0.1 to 0.5 mm, more preferably 0.15 to 0.45 mm. The width of the part of block BL1 that contacts the cutting strip DT is, for example, about 0.3 to 0.6 mm, the width of block BL2 is, for example, about 0.6 to 1.2 mm, and the width of block BL3 is, for example, about 0.8 to 1.2 mm.

[0056] The height of the upper surface of each of the four blocks BL1 to BL4 is equal to that of the others in the initial state (when blocks BL1 to BL4 are not in motion), and is also equal to or lower than the height of the upper surface of the dome plate DP.

[0057] like Figure 1 As shown, the four blocks BL1 to BL4 can move up and down independently using the four drive shafts of the drive unit 86c, namely the needles NDL4 to NDL1. The drive unit 86c includes a motor (not shown) and a plunger mechanism that converts the rotation of the motor into up and down movement using a cam or connecting rod, thereby imparting up and down movement to the needles NDL4 to NDL1.

[0058] For example, the push-up unit TU can perform the following actions: simultaneously push up four blocks BL1 to BL4, then simultaneously push up the inner blocks BL2 to BL4, then simultaneously push up blocks BL3 and BL4, and then push up block BL4 again, forming a pyramid shape. Alternatively, for example, the push-up unit TU can simultaneously push up four blocks BL1 to BL4 and then lower them in the order of blocks BL1, BL2, and BL3. In this disclosure, the latter action is referred to as RMS (Reverse Multi Step).

[0059] To make this implementation method clearer, RMS will be used as an example. Figure 4 This section explains the issues encountered when separating the bare chip from the dicing tape. Figure 4 This diagram illustrates the problem points when pushing the block up. Figure 4 (a) is a cross-sectional view showing the state where all blocks are pushed up to the highest point simultaneously when the protrusion is very short. Figure 4 (b) is a cross-sectional view showing the state of all blocks being pushed up to the highest point simultaneously with the protruding minister.

[0060] like Figure 4 As shown in (a), by shortening the length (LO1) of the protrusion, even with a very low upward push height (H) of the outermost block BL1, the deformation of the picked-up bare chip (the bare chip to be peeled off) D is small, and peeling occurs at the periphery of the bare chip D. Consequently, the stress applied to the bare chip D is reduced. However, the peripheral bare chips (peripheral bare chips) Dp adjacent to the bare chip to be peeled off D are prone to deformation.

[0061] Set the upward push height (H) of block BL1 to the same as... Figure 4 In the case where the height (H) shown in (a) is the same, such as Figure 4 As shown in (b), the length (LO2) of the protrusion is set to be greater than that of the protrusion. Figure 4 The width (LO1) of the protrusion shown in (a) is long, thereby reducing the deformation of the surrounding bare chip Dp. However, as Figure 4 As shown in (b), the deformation increases during peeling of the outer periphery of the bare die D. Consequently, the stress applied to the bare die D increases. Furthermore, given the same dimensions of the bare die D, Figure 4 (b) shows the size of the block (WB2) compared to Figure 4 The size of the block (WB1) shown in (a) is small.

[0062] When using the outermost block BL1 as the starting point for stripping the target bare chip D, the aforementioned opposite problem exists. Therefore, it is necessary not only to reduce the size of the target bare chip D, but also to reduce the deformation of the surrounding bare chips Dp.

[0063] use Figure 5 This document outlines the implementation method that addresses the aforementioned problems. Figure 5 This is a diagram illustrating the block-pushing action in the implementation method. Figure 5 (a) is a cross-sectional view showing the state of the block during the pushing process. Figure 5 (b) is a cross-sectional view showing the final state of the push action on the block.

[0064] like Figure 5 As shown in (a), the size of the block is increased while the protrusion is shortened. Then, when pushing up the four blocks BL1 to BL4, the pushing up of the outermost block BL1 is stopped at the time point when the outer periphery of the bare chip D is peeled off, as shown in (a). Figure 5 As shown in (b), the inner blocks BL2 to BL4 are also pushed upwards, thereby preventing deformation of the surrounding bare chip Dp. In this way, the length (LO) of the protrusion is, for example, 0.1 to 0.5 mm. Furthermore, the height (H1) at which the outermost block BL1 stops is, for example, 0.075 to 0.12 mm. The height (H2) of pushing the inner blocks BL2 to BL4 upwards is, for example, 0.15 to 0.2 mm.

[0065] Next, use Figure 1 This section explains the method for setting and controlling the action of the push-up unit TU.

[0066] The main controller 81a and the working controller 81b are configured to control the needles NDL4 to NDL1 that drive the four blocks BL1 to BL4 respectively, based on a time map process that sets the step time, the speed of the block's rise or fall, and the height (position) of the block for each block and each step, in terms of the operation of the four blocks BL1 to BL4 of the push unit TU.

[0067] Multiple timemap processes with different settings are prepared in advance. The user selects a timemap process from among the multiple timemap processes using a GUI (Graphical User Interface) and inputs the settings for the selected timemap process. Alternatively, the user can communicate data from an external machine to a semiconductor manufacturing apparatus such as a chip mounter with the pre-entered settings for the timemap process, or install a semiconductor memory such as a magnetic disk (e.g., magnetic disk, floppy disk, or hard disk, optical disk, CD, DVD, optical disc, USB memory, or memory card) into the semiconductor manufacturing apparatus. In addition, the main controller 81a instructs the operation controller 81b to rewrite the timemap process in real time based on the status detected by sensors 87a, 87b, 87c, etc., so as to make changes to the upward operation.

[0068] In this way, by using the time-map process settings, the actions of each block BL1 to BL4 of the push-up unit TU can be automatically set during the push-up operation step, enabling the push-up unit TU to perform various actions. An example of its operation will be described below.

[0069] use Figure 6 Explain the actions of RMS. Figure 6 This is a diagram illustrating the push-up sequence of RMS in the implementation method.

[0070] (Step Zero: STEP0)

[0071] The pickup operation begins when the target bare die D on the cutting tape DT is positioned between the push unit TU and the collet CLT. Once positioning is complete, the control unit CNT evacuates the vacuum via the suction port DPa of the push unit TU and the gaps between blocks BL1-BL4, thereby adsorbing the cutting tape DT onto the upper surface of the push unit TU. At this point, the upper surfaces of the four blocks BL1-BL4 are at the same height as the upper surface of the dome plate DP (initial position). In this state, the control unit CNT supplies vacuum from a vacuum supply source not shown, causing the collet CLT to descend and land towards the equipment side of the bare die D while evacuating the vacuum.

[0072] (Step 1)

[0073] Subsequently, the control unit CNT simultaneously raises the four blocks BL1 to BL4 at a predetermined speed (s1). Here, the bare die D rises while being held by the collet CLT and the four blocks BL1 to BL4, but the periphery of the cutting tape DT is vacuum-adhered to the periphery of the push unit TU, i.e., the dome plate DP. Therefore, tension is generated around the bare die D, resulting in the peeling of the cutting tape DT beginning around the periphery of the bare die D. The control unit CNT stops the outermost block BL1 at a predetermined peeling height (H1), and continues to raise the inner blocks BL2 to BL4 at a predetermined speed (s1) until they reach a predetermined height (H2). By stopping the outermost block BL1, a portion of the support for the cutting tape DT is released, and the tension of the cutting tape DT facilitates its peeling. Here, s1 is, for example, 5 mm / sec.

[0074] (Step 2)

[0075] Next, the control unit CNT lowers the outermost block BL1 at a certain speed (s2) until it reaches the same height as the upper surface of the dome plate DP. Here, s2 is, for example, 5 mm / sec. Alternatively, the second block BL2 can be lowered to a predetermined height (H1) in parallel with the lowering of the outermost block BL1.

[0076] (Step 3)

[0077] Next, the control unit CNT lowers the second BL2 at a certain speed (s2) to the same height as the upper surface of the dome plate DP. Here, by lowering the second BL2 to the height of the upper surface of the dome plate DP, another part of the support of the cutting strip DT is released, and the tension of the cutting strip DT is also used to promote the peeling of the cutting strip DT.

[0078] (Step 4)

[0079] Next, the control unit CNT lowers the third BL3 at a certain speed (s2) until it reaches the same height as the upper surface of the dome plate DP. Here, by lowering the third BL3 to the height of the upper surface of the dome plate DP, another part of the support of the cutting strip DT is released, and the tension of the cutting strip DT is also used to promote the peeling of the cutting strip DT.

[0080] Subsequently, the control unit CNT pulls up the collet CLT from above, while simultaneously lowering the fourth BL4 at a certain speed (s3) to return it to its initial position. Here, s3 is, for example, 5 mm / sec. Thus, the operation of peeling the bare chip D from the cutting tape DT is completed.

[0081] The length (LO) of the protrusion is reduced so that the outermost block BL1 stops at a predetermined height (H1), while the inner blocks BL2 to BL4 rise further to a predetermined height (H2). Thus, when the outermost block BL1 acts as the peeling starting point, the deformation of the surrounding bare chip Dp and the target bare chip D is minimized while the height difference remains constant as the subsequent inner blocks BL2 to BL4 rise. This reduces stress on the target bare chip D and the surrounding bare chips Dp, preventing breakage or loss.

[0082] Furthermore, by reducing the length (LO) of the protrusion, the outer periphery of the target bare chip D can be peeled off using the cutting strip DT at a very low push height. Additionally, by making the outermost block BL1 lower than the total push height, deformation of the peripheral bare chips Dp can be reduced. Furthermore, by reducing the width (LO) of the protrusion, the distance from the end face of the outermost block BL1 to the end face of the target bare chip D is shortened, making the target bare chip D less prone to deformation. Finally, by reducing the total push height (H2) of blocks BL2 to BL4, the operation time is shortened, thereby improving productivity.

[0083] <Variation Example>

[0084] Hereinafter, several representative variations of the embodiments are illustrated. In the following description of the variations, the same reference numerals as those in the above embodiments may be used for parts having the same structure and function as those in the above embodiments. Furthermore, the descriptions in the above embodiments may be appropriately referenced to the extent that they do not contradict each other. In addition, a part of the above embodiments, and all or part of multiple variations, may be appropriately and in combination to the extent that they do not contradict each other.

[0085] (First variation)

[0086] First, to clarify this variation, we will address the issue of peeling the bare die from the dicing tape, using RMS as an example. Figure 7 Please provide an explanation. Figure 7 This diagram illustrates the problem points when pushing the block up. Figure 7 (a) is a cross-sectional view showing the state of the blocks other than the innermost block when the bare die size is increased without changing the block size. Figure 7 (b) is a cross-sectional view showing the state of the blocks other than the innermost block when the block size is increased.

[0087] like Figure 7 As shown in (a), when the size of the bare chip D increases without changing the size of block BLK (WB1), the width of the protrusion will increase. Here, the four blocks BL1 to BL4 of the push-up unit are collectively referred to as block BLK. In order to maintain a smaller width of the protrusion, as... Figure 7 As shown in (b), the size of BLK (WB2) needs to be increased to match the size of the bare chip D.

[0088] Therefore, given a fixed number of blocks in the push-up unit TU, when the size of the bare die D to be peeled is increased, the width of each of the four blocks BL1 to BL4 is increased, i.e., the peeling area is increased. However, in order to stably hold the bare die D in the collet CLT, peeling needs to be performed up to the vacuum suction hole of the collet CLT. Furthermore, to prevent deformation of the bare die D in the initial stage of the peeling process, the peeling area needs to be minimized as much as possible. Figure 7 As shown in (b), from the viewpoint of stress on the bare die during the upward pushing action of the cutting block, while keeping the length of the protrusion and the block width of the blocks BL1 to BL3 that are pulled down relatively small, the block width (WBL2) of the innermost block BL4 is increased by more than Figure 7(a) shows that the block width (WBL1) of block BL4 is large, even with an increased peeling area. By increasing the peeling area, the adhesive force of the cutting strip DT applied to the bare die D during peeling is increased, thus increasing the stress on the bare die D being peeled, raising concerns about pick-up errors or, in the worst case, damage to the bare die.

[0089] Therefore, in the first variation, the number of blocks of the push-up unit TU is increased compared to the implementation method. Using Figure 8 as well as Figure 9 Explain the push-up element in the first variation. Figure 8 This is a partial cross-sectional view of the push-up unit in the first modified example, showing its connection with the cutting strip. Figure 9 yes Figure 8 The top view of the push-up unit is shown.

[0090] Five blocks BL0 to BL4, which push the cutting strip DT upwards, are assembled at the center of the pushing unit TU. In this embodiment, a zeroth block BL0 with a longer outer perimeter is arranged outside the first block BL1. The zeroth block BL0 is cylindrical.

[0091] Among the five blocks BL0 to BL4, the outermost block BL0, which has the largest outer perimeter, has an outer perimeter that is one size smaller than the bare chip D that is being stripped.

[0092] The length (LO) of the protrusion is the same as in the embodiment. The width of the outermost block BL0, where it contacts the cutting strip DT, is, for example, about 0.3 to 0.6 mm. The width of the inner blocks BL1 to BL4 is the same as in the embodiment. Here, the area (peeling area) of the surface of the innermost block BL4 that contacts the cutting strip DT is preferably about 30% or less of the area of ​​the bare chip D.

[0093] The height of the upper surface of each of the five blocks BL0 to BL4 is equal in the initial state (when the five blocks BL0 to BL4 are not in operation). In addition, the height of the upper surface of the dome plate DP is equal or lower.

[0094] The five blocks BL0 to BL4 can move up and down independently using the five drive shafts of the drive unit 86c, namely the needle parts NDL5 to NDL1. The drive unit 86c has a motor and a plunger mechanism that uses a cam or connecting rod to convert the rotation of the motor into up and down movement, thereby imparting up and down movement to the needle parts NDL5 to NDL1.

[0095] use Figure 10 Explain the block push-up in the first variation. Figure 10 This diagram illustrates the pushing action of the block in the first variation example. Figure 10 (a) is a cross-sectional view showing the state of the block during the pushing process. Figure 10(b) shows a cross-sectional view of the final state of the push operation on the block.

[0096] like Figure 10 As shown in (a), the size of the blocks is increased to shorten the protrusion. Then, when pushing up five blocks BL0 to BL4, the pushing up of the outermost block BL0 is stopped at the time point when the outer periphery of the bare chip D is peeled off, as shown in (a). Figure 10 As shown in (b), deformation of the peripheral bare chip Dp is prevented by further pushing the inner blocks BL1 to BL4 upwards. The width (WO) of the protrusion is, for example, 0.15 to 0.45 mm. Furthermore, the height (H1) at which the outermost block BL0 stops is the same as in the embodiment, for example, 0.075 to 0.12 mm. The height (H2) at which the inner blocks BL1 to BL4 are pushed upwards is the same as in the embodiment, for example, 0.15 to 0.2 mm.

[0097] In the first variation, the RMS operates the same as in the implementation. The outermost block in the first variation, i.e., the zeroth block BL0, performs the same operation as the outermost block in the implementation, i.e., the first block BL1. The inner blocks in the first variation, i.e., blocks BL1 to BL4, perform the same operation as the inner blocks in the implementation, i.e., blocks BL2 to BL4.

[0098] (Second variation)

[0099] In the first variation, the five blocks BL0 to BL4 of the push-up unit TU are pushed upwards using a drive shaft, i.e., five needles NDL5 to NDL1. In contrast, in the second variation, instead of adding a drive shaft (needle) to the push-up unit TU itself, the four-stage push-up mechanism of the embodiment is used to increase the size of the push-up blocks. Figures 11-13 Explain the structure and operation of the push-up unit in the second variation. Figure 11 (a) is a cross-sectional view showing the initial state of the push-up unit in the second variation. Figure 11 (b) is a cross-sectional view showing the first state of the push-up unit in the second variation. Figure 12 (a) is a cross-sectional view showing the second state of the push-up unit in the second variation. Figure 12 (b) is a cross-sectional view showing the third state of the push-up unit in the second variation. Figure 13 (a) is a cross-sectional view showing the fourth state of the push-up unit in the second variation. Figure 13 (b) is a cross-sectional view showing the fifth state of the push-up unit in the second variation.

[0100] Five blocks BL0 to BL4, which push the cutting strip DT upwards, are assembled at the center of the pushing unit TU. Inside the zeroth block BL0, which has the longest outer perimeter, are arranged the following blocks: a first block BL1, a second block BL2, and a third block BL3, each with a shorter outer perimeter than BL0. Inside the third block BL3 is the fourth block BL4, which has the shortest outer perimeter. A compression coil spring CS and a spring-loaded pin SP connected to the first block BL1 are interposed between the outer zeroth block BL0 and the first block BL1. The inner blocks BL1 to BL4 each move up and down in conjunction with pins NDL4 to NDL1, which move up and down using a drive mechanism (not shown).

[0101] In the second variation, the length and width of the outer periphery of the five blocks BL0 to BL4, as well as the width of the protrusion, are the same as in the first variation. The height of the upper surface of each of the five blocks BL0 to BL4 is equal to that of each other in the initial state (when the five blocks BL0 to BL4 are not in motion), and is also equal to the height of the upper surface of the dome plate DP. A compression coil spring CS and a spring-pressing pin SP maintain the distance between the outermost zeroth block BL0 and the first block BL1.

[0102] In order to simultaneously push the five blocks BL0 to BL4 upwards, the needle parts NDL4 to NDL1 (not shown) are pressed upwards, thereby pushing up the inner blocks BL1 to BL4 that are respectively connected to the needle parts NDL4 to NDL1. Thus, as... Figure 11 As shown in (b), the outermost block BL0 is pushed upwards by the spring force of the compression helical spring CS, which is located between the outermost block BL0 and the first block BL1, thus simultaneously pushing up all five blocks BL0 to BL4. Then, by bringing a portion of the outermost block BL0 into contact with the dome plate DP, the rise of the outermost block BL0 stops at a predetermined height (H1) (first state). At this time, most of the area of ​​the bare die D to be peeled off is supported by the upper surfaces of the five blocks BL0 to BL4, and peeling of the bare die D at the interface with the cutting strip DT is effectively performed in the area outside the outer periphery (corner) of the upper surface of the outermost block BL0.

[0103] Furthermore, the compression helical spring CS needs to possess a spring force sufficient to lift the outermost block BL0 at least enough to resist the tension of the dicing tape DT. If the spring force of the compression helical spring CS is less than the tension of the dicing tape DT, the outermost block BL0 will not lift even when the push pin NDL4 is pushed up. Therefore, the upper surface of the outermost block BL0 cannot support the bare die D. In this case, because sufficient stress cannot be concentrated at the peeling point between the bare die D and the dicing tape DT, problems such as a decrease in peeling speed or excessive bending stress on the bare die D, causing it to break, may occur.

[0104] Next, as Figure 12 As shown in (a), the inner blocks BL1 to BL4 are simultaneously pushed upwards to a predetermined height (H2), and the dicing tape DT is pushed upwards (second state). As a result, the position of the outer periphery (corner) of the upper surface of the first block BL1 supporting the bare die D is moved further inwards than when it was supported by the outermost block BL0. Therefore, the separation of the bare die D from the dicing tape DT proceeds from the region further outwards than the outer periphery of the upper surface of the first block BL1 toward the center of the bare die D.

[0105] In order to push the four blocks BL1 to BL4 upwards simultaneously, the four needle parts NDL4 to NDL1 (not shown) are pushed upwards, and the four blocks BL1 to BL4 connected to the four needle parts NDL4 to NDL1 are further pushed upwards.

[0106] When the four blocks BL1 to BL4 are pushed upwards, in order to facilitate the separation of the bare chip D from the dicing tape DT, the internal pressure of the gap between the five blocks BL0 to BL4 is reduced, which attracts the dicing tape DT, which is in contact with the bare chip D, downwards. In addition, the internal pressure of the groove DPb is reduced, so that the dicing tape DT, which is in contact with the upper surface of the dome plate DP, adheres tightly to the upper surface of the dome plate DP.

[0107] Next, as Figure 12 As shown in (b), the first block BL1 is pulled downwards to the height (H0) of the outermost block BL0, and the back side of the bare chip D is supported on the upper surface of the inner blocks BL2 to BL4 (third state). In order to pull the first block BL1 downwards, the first block BL1 connected to the needle part NDL4 is pulled down by pulling down the needle part ND4. As a result, the position of the outer periphery (corner) of the upper surface of the second block BL2 supporting the bare chip D is moved further inwards than when it was supported by the first block BL1. Therefore, the peeling of the bare chip D from the dicing tape DT proceeds from the area outside the outer periphery of the upper surface of the second block BL2 towards the center of the bare chip D.

[0108] Next, as Figure 13As shown in (a), the first block BL1 is pulled down to the height of the initial state (the upper surface of the dome plate DP), thereby the outermost block BL0 also drops to the height of the initial state (the fourth state).

[0109] Next, as Figure 13 As shown in (b), the second BL2 is pulled down to the initial height (dome plate DP), and the back side of the bare chip D is supported by the upper surfaces of the inner blocks BL3 and BL4 (fifth state). To pull the second BL2 down, the second BL2, connected to the needle part NDL3, is pulled down by pulling down the needle part ND3. As a result, the outer periphery (corner) of the upper surface of the block BL3 supporting the bare chip D moves further inward than when supported by the second BL2. Therefore, the peeling of the bare chip D from the dicing tape DT proceeds from the area outside the outer periphery of the upper surface of the third BL3 towards the center of the bare chip D.

[0110] The third BL3 was pulled down to the initial height (DP of the dome plate) just like the second BL2.

[0111] Next, pull down the innermost block BL4 and pull up the collet CLT, thus completing the operation of peeling the bare chip D from the cutting tape DT.

[0112] The area of ​​the upper surface of the innermost block BL4 needs to be reduced to the point where the bare die D can be peeled from the dicing tape DT using only the attraction force of the collet CLT. If the area of ​​the upper surface of the innermost block BL4 is increased, the contact area between the bare die D and the dicing tape DT will increase, and the adhesion between them will also increase. Therefore, the force of the bare die D attracted by the collet CLT alone will not be enough to peel the bare die D from the dicing tape DT.

[0113] In the second variation, a zeroth block BL0, driven by a compression coil spring, is added to the outermost block (the first block BL1) of the multi-axis push-up unit in the previous embodiment. By hardware-linking the outermost block (the zeroth block BL0) and the inner first block BL1 in the second variation, the zeroth block BL0 and the first block BL1 can be pushed upwards with a height difference. This allows for a configuration without adding a drive shaft. Furthermore, it facilitates the setting of protrusions and setting conditions.

[0114] (Third variation)

[0115] In the first variation, the position of block BL0 is fixed at the outermost perimeter. In contrast, in the third variation, a structure is designed to divide the outermost perimeter block into multiple blocks, allowing for positional adjustments. Figure 14 Explain the push-up unit in the third variation. Figure 14 It is the upper surface of the key part of the push-up element in the third variation example. Figure 14 (a) is a diagram showing the outermost block configured on the innermost side. Figure 14 (b) is a diagram showing the outermost block in the configuration of the outermost side.

[0116] From a top view, the outermost block BL0 is formed by four L-shaped blocks BL0a to BL0b. The distance between the first block BL1 and the end DPc of the opening in the dome plate DP is set to be larger than the sum of the width of the outermost block BL0 and the gap between the blocks. The positions of the four blocks BL0a to BL0b can be adjusted individually. Therefore, the amount of the protrusion can be set to the optimal value using the same hardware.

[0117] In addition, Figure 14 In (a), the distance between the outermost blocks BL0a to BL0b and the end DPc of the opening of the dome plate DP is larger than the usual gap, reaching its maximum. The distance between the inner circumference of the outermost blocks BL0a to BL0b and the outer circumference of the first block BL1 is the usual gap. Figure 14 In (b), the distance between the outer periphery of the outermost blocks BL0a to BL0b and the end DPc of the opening of the dome plate DP is the normal gap. The distance between the inner periphery of the outermost blocks BL0a to BL0b and the outer periphery of the first block BL1 is larger than the normal gap, and is the maximum.

[0118] (Fourth variation)

[0119] In the fourth variation, the contact portion between the outermost peripheral block and the cutting strip DT can be replaced. (Using...) Figure 15 Explain the push-up unit in the fourth variation. Figure 15 It is the upper surface of the key part of the push-up element in the fourth variation example. Figure 15 (a) is a diagram showing the outermost block configured on the innermost side. Figure 15 (b) is a diagram showing the outermost block in the configuration of the outermost block.

[0120] Multiple blocks of different sizes (length of the outer perimeter) are prepared as the outermost block BL0. A mounting part corresponding to the final block BL0 is set between the first block BL1 and the end DPc of the opening of the dome plate DP, and is designed to be replaceable. Thus, by replacing only a part of the block BLK, the protrusion amount can be set to the optimal amount at a low cost. Here, the five blocks BL0 to BL4 of the push-up unit are collectively referred to as block BLK.

[0121] In addition, Figure 15 In (a), the distance between the outer periphery of the outermost block BL0 and the end DPc of the opening of the dome plate DP is larger than the usual gap, reaching its maximum. The distance between the inner periphery of the outermost block BL0 and the outer periphery of the first block BL1 is the usual gap. Figure 15In (b), the distance between the outer periphery of the outermost block BL0 and the end DPc of the opening of the dome plate DP is the normal gap. The distance between the inner periphery of the outermost block BL0 and the outer periphery of the first block BL1 is larger than the normal gap, and is the maximum.

[0122]

Example

[0123] Figure 16 This is a conceptual diagram of the chip mounting machine in the embodiment, viewed from above. Figure 17 This means that in Figure 16 The diagram shows the movement of the pickup head and the placement head when viewed from the direction of arrow A.

[0124] As an example of a chip mounting apparatus, a chip mounting machine 10 generally includes a bare chip supply unit 1 for supplying bare chips D mounted on a substrate S, a pick-up unit 2, an intermediate stage unit 3, a mounting unit 4, a transport unit 5, a substrate supply unit 6, a substrate removal unit 7, and a control unit 8 for monitoring and controlling the operation of each part. The Y-axis direction is the front-to-back direction of the chip mounting machine 10, and the X-axis direction is the left-to-right direction. The bare chip supply unit 1 is located near the front of the chip mounting machine 10, and the mounting unit 4 is located at the far side. Here, the substrate S is printed with one or more product areas (hereinafter referred to as package areas P) that will eventually become a package.

[0125] First, the bare die supply unit 1 supplies a bare die D mounted on the packaging area P of the substrate S. The bare die supply unit 1 includes a wafer holding stage 12 for holding a wafer 11 and a push-up unit 13 (shown in dashed lines) for pushing the bare die D from the wafer 11. The bare die supply unit 1 moves in the XY axis direction using a driving means (not shown) to move the picked-up bare die D to the position of the push-up unit 13.

[0126] The pickup unit 2 includes a pickup head 21 for picking up the bare chip D, a Y-drive unit 23 for moving the pickup head 21 in the Y-axis direction, and various drive units (not shown) for raising, lowering, rotating, and moving the collet 22 in the X-axis direction. The pickup head 21 has a collet 22 (also see) that holds the pushed-up bare chip D at its front end. Figure 17 The pickup head 21 picks up the bare chip D from the bare chip supply unit 1 and places it on the intermediate stage 31. The pickup head 21 has drive units (not shown) that cause the collet 22 to lift, rotate, and move along the X-axis.

[0127] The intermediate stage 3 has an intermediate stage 31 for temporarily mounting the bare chip D, and a stage recognition camera 32 for recognizing the bare chip D on the intermediate stage 31.

[0128] The mounting unit 4 picks up the bare die D from the intermediate stage 31 and mounts it onto the packaging area P of the transported substrate S, or mounts it by stacking it onto the bare die already mounted on the packaging area P of the substrate S. Similar to the pick-up head 21, the mounting unit 4 includes a collet 42 (also see) that holds the bare die D at its front end. Figure 17 The mounting head 41; the Y-drive unit 43 that moves the mounting head 41 in the Y-axis direction; and the substrate recognition camera 44 that identifies the mounting position by photographing the position recognition mark (not shown) of the packaging area P of the substrate S.

[0129] Using this configuration, the mounting head 41 corrects the pickup position / posture based on the camera data of the stage recognition camera 32, picks up the bare chip D from the intermediate stage 31, and mounts the bare chip D onto the substrate based on the camera data of the substrate recognition camera 44.

[0130] The transport unit 5 has a substrate transport claw 51 for gripping and transporting the substrate S, and a transport channel 52 for moving the substrate S. The substrate S is moved by driving a nut (not shown) of the substrate transport claw 51 provided in the transport channel 52 using a ball screw (not shown) provided along the transport channel 52.

[0131] According to this configuration, the substrate S moves from the substrate supply section 6 along the transport channel 52 to the mounting position, and after mounting, it moves to the substrate delivery section 7 and is delivered to the substrate delivery section 7.

[0132] The control unit (control device) 8 includes: a memory that stores programs (software) that monitor and control the operation of each part of the chip placement machine 10; and a central processing unit (CPU) that executes the programs stored in the memory.

[0133] Next, use Figure 18 Explain the structure of bare chip supply unit 1. Figure 18 It is shown Figure 16 A schematic cross-sectional view of the main parts of the bare chip supply department.

[0134] The bare die supply unit 1 includes a wafer holding stage 12 that moves in the horizontal direction (XY axis direction) and a push-up unit 13 that moves in the vertical direction. The wafer holding stage 12 includes an extension ring 15 that holds a wafer ring 14 and a support ring 17 that horizontally positions a dicing tape 16 held in the wafer ring 14 and to which multiple bare dies D are attached. The push-up unit 13 is disposed inside the support ring 17.

[0135] When the bare die supply unit 1 pushes up the bare die D, the expansion ring 15 holding the wafer ring 14 descends. As a result, the dicing tape 16 held in the wafer ring 14 is stretched, expanding the spacing of the bare dies D. The bare die D is then pushed up from below by the push unit 13, improving the pickability of the bare die D. Furthermore, the adhesive that bonds the bare die to the substrate changes from a liquid to a film, and a film-like adhesive material called a die-attach film (DAF) 18 is attached between the wafer 11 and the dicing tape 16. The wafer 11 with the die-attach film 18 is diced relative to the wafer 11 and the die-attach film 18. Therefore, in the peeling process, the wafer 11 and the die-attach film 18 are peeled off using the dicing tape 16. Furthermore, the die-attach film 18 is omitted hereafter, and the peeling process will be described.

[0136] Next, use Figure 19 This describes a method for manufacturing semiconductor devices using the chip mounting machine described in the embodiment. Figure 19 It shows that it was used Figure 16 The flowchart shown illustrates a method for manufacturing semiconductor devices using a chip mounting machine.

[0137] (Step S11: Wafer / Substrate Handling Process)

[0138] The wafer ring 14, which holds the dicing tape 16 with the bare dies D separated from the wafer 11 attached, is stored in a wafer cassette (not shown) and transferred into the die mounter 10. The control unit 8 supplies the wafer ring 14 from the wafer cassette filled with the wafer ring 14 to the bare die supply unit 1. Additionally, a substrate S is prepared and transferred into the die mounter 10. The control unit 8 uses the substrate supply unit 6 to mount the substrate S onto the substrate transport claw 51.

[0139] (Step S12: Pick-up process)

[0140] Control unit 8 peels off the bare die D as described above and picks up the peeled bare die D from wafer 11. Thus, the bare die D, peeled off from the dicing tape 16 along with the die-attach film 18, is held and held by chuck 22 and transported to the next process (step S13). Then, when chuck 22, which has transported the bare die D to the next process, returns to bare die supply unit 1, the next bare die D is peeled off from dicing tape 16 in the same order as described above. Thereafter, bare dies D are peeled off one by one from dicing tape 16 in the same order.

[0141] (Step S13: Mounting process)

[0142] The control unit 8 mounts the picked-up bare chip onto the substrate S or stacks it on the already mounted bare chip. The control unit 8 places the bare chip D picked up from the wafer 11 onto the intermediate stage 31, picks up the bare chip D again from the intermediate stage 31 using the mounting head 41, and mounts it onto the transported substrate S.

[0143] (Step S14: Substrate removal process)

[0144] The control unit 8 uses the substrate removal unit 7 to remove the substrate S with the bare chip D mounted on it from the substrate transport claw 51. The substrate S is then removed from the chip mounting machine 10.

[0145] In this manner, a bare die D is mounted on a substrate S using a die-attach film 18 and removed from a die-mounting machine. Subsequently, in a wire-mounting process, it is electrically connected to the electrodes of the substrate S via Au wires. Next, the substrate S with the bare die D mounted is moved into the die-mounting machine, and a second bare die D is stacked on top of the bare die D mounted on the substrate S using the die-attach film 18. After being removed from the die-mounting machine, it is electrically connected to the electrodes of the substrate S via Au wires in a wire-mounting process. After being peeled from the dicing tape 16 using the above method, the second bare die D is transported to a die-mounting process and stacked on top of the bare die D. After repeating the above process a predetermined number of times, the substrate S is transported to an injection molding process, where multiple bare dies D and Au wires are encapsulated using injection molding resin (not shown), completing the stacking and encapsulation process.

[0146] In this case, when assembling a stacked package that three-dimensionally mounts multiple bare chips onto a substrate, the thickness of the bare chips must be reduced to less than 0.02 mm to prevent an increase in package thickness. On the other hand, the thickness of the dicing tape is about 0.1 mm, so the thickness of the dicing tape is also 4 to 5 times the thickness of the bare chips.

[0147] When peeling such a thin bare chip from the dicing tape, the deformation of the bare chip, which follows the deformation of the dicing tape, is more likely to occur significantly, but damage to the bare chip can be reduced when picking it up from the dicing tape using the chip mounter of this embodiment.

[0148] The above describes the disclosure made by the inventors of this disclosure in detail based on the implementation methods, variations, and embodiments. However, this disclosure is not limited to the above implementation methods, variations, and embodiments, and various changes can be made.

[0149] For example, the implementation describes a number of blocks of four, and the variant describes a number of blocks of five, but the number of blocks can also be set to six or more depending on the bare chip size.

[0150] In addition, it is explained that the multiple blocks of the push-up unit are concentric quadrilaterals, but they can also be concentric circles or concentric ellipses, or the quadrilateral blocks can be arranged in parallel to form the unit.

[0151] In addition, while an example of using a sheet adhesive film is described in the embodiments, a pre-formed portion for applying adhesive to the substrate may also be provided without using a sheet adhesive film.

[0152] In addition, the embodiment describes a chip mounting machine that uses a pick-up head to pick up a bare chip from a bare chip supply unit and place it on an intermediate stage, and uses a mounting head to mount the bare chip placed on the intermediate stage onto a substrate. However, it is not limited to this and can be applied to a chip mounting apparatus that picks up a bare chip from a bare chip supply unit.

[0153] For example, it can also be applied to chip mounting machines that do not have an intermediate stage and a pickup head, and use a mounting head to mount bare chips from the bare chip supply section onto a substrate.

[0154] In addition, it can also be applied to flip chip mounting machines that do not have an intermediate stage, pick up bare chips from the bare chip supply section, rotate the pick-up head upwards, transfer the bare chips to the mounting head, and use the mounting head to mount them onto the substrate.

Claims

1. A chip mounting apparatus, characterized in that, have: The push-up unit has multiple blocks that contact the cutting strip and a dome plate located outside the multiple blocks and capable of adsorbing the cutting strip, and uses the multiple blocks to push the bare chip upward from below the cutting strip. The head has a clamp that adsorbs the bare chip and is capable of moving up and down; and The control unit controls the movement of the push-up unit and the head. The control unit is configured such that, The dome plate is used to adsorb the cutting strip. The head is used to grip and drop the die onto the bare chip. The bare chip is adsorbed using the clamp. The plurality of blocks are raised from the dome plate. The outermost block of the plurality of blocks stops rising at the height at which the bare chip is peeled from the dicing strip. The blocks on the inner side of the plurality of blocks, excluding the outermost block, are raised further from the peeling height to a predetermined height. This causes the outermost block to decrease from the height of the peel. The adjacent block that is inside the outermost block is lowered from the specified height. The block adjacent to the outer side of the innermost block, which is located on the innermost side, is lowered from the predetermined height.

2. The chip mounting apparatus according to claim 1, characterized in that, The control unit is configured to further utilize the head to raise the collet.

3. The chip mounting apparatus according to claim 2, characterized in that, It also has: Multiple drive shafts connected to each of the multiple blocks; and The drive unit that drives the plurality of drive shafts, The control unit is configured to use the drive unit to move the plurality of drive shafts up and down independently.

4. The chip mounting apparatus according to claim 2, characterized in that, It also has: Multiple drive shafts connected to each of the blocks other than the outermost peripheral block; A drive unit that drives the plurality of drive shafts; and A compression helical spring is provided between the outermost block and the adjacent block. The control unit is configured to use the drive unit to move the plurality of drive shafts up and down independently.

5. The chip mounting apparatus according to claim 2, characterized in that, The width of the portion of the outermost block that contacts the cutting strip is either the narrowest among the blocks or the same as the adjacent block. The width of the portion of the innermost block that contacts the dicing strip is the widest among the plurality of blocks, and the area of ​​the portion of the innermost block that contacts the dicing strip is less than 30% of the area of ​​the bare chip.

6. The chip mounting apparatus according to claim 2, characterized in that, The protrusion is less than the width of the portion of the outermost block that contacts the cutting strip and more than the thickness of the cutting strip. The protrusion is the distance between the outermost peripheral end of the outermost block and the outermost peripheral end of the bare chip.

7. The chip mounting apparatus according to claim 6, characterized in that, The protrusion is greater than 0.15 mm and less than 0.45 mm.

8. The chip mounting apparatus according to claim 2, characterized in that, The height of the outermost block is above 0.075 mm and below 0.12 mm. The specified height is above 0.15mm and below 0.2mm.

9. The chip mounting apparatus according to claim 1, characterized in that, The head is a pickup head. The chip mounting device also includes: An intermediate stage for mounting bare chips picked up using the pickup head; and A mounting head that mounts the bare chip placed on the intermediate stage onto a substrate or an already mounted bare chip.

10. The chip mounting apparatus according to claim 1, characterized in that, The outermost block is divided into multiple parts and configured to allow for positional adjustment in the outward direction.

11. The chip mounting apparatus according to claim 1, characterized in that, The outermost block is configured to allow for replacement of the portion that contacts the cutting strip.

12. A method for manufacturing a semiconductor device, characterized in that, include: A loading process is performed to load a wafer ring holding a dicing tape into a chip mounting apparatus equipped with a push-up unit and a head. The push-up unit has multiple blocks that contact the dicing tape and a dome plate located outside the multiple blocks that can hold the dicing tape. The multiple blocks are used to push the bare chip upward from below the dicing tape. The head has a collet that holds the bare chip and can move up and down. as well as In the pick-up process, the bare chip is pushed up by the push-up unit and picked up by the collet. In the picking process, The dome plate is used to adsorb the cutting strip. The head is used to grip and drop the die onto the bare chip. The bare chip is adsorbed using the clamp. The plurality of blocks are raised from the dome plate. The outermost block of the plurality of blocks stops rising at the height at which the bare chip is peeled from the dicing strip. The blocks, excluding the outermost block, are raised further from the peeling height to a predetermined height. This causes the outermost block to decrease from the height of the peel. The adjacent block that is inside the outermost block is lowered from the specified height. The block adjacent to the outer side of the innermost block among the plurality of blocks is lowered from the predetermined height. The head is used to raise the collet.

13. The method for manufacturing a semiconductor device according to claim 12, characterized in that, It also includes a mounting process, in which the bare chip is mounted onto a substrate or onto an already mounted bare chip.

14. The method for manufacturing a semiconductor device according to claim 13, characterized in that, The picking process also includes the step of placing the picked-up bare chip onto an intermediate stage. The mounting process also includes a step of picking up the bare chip from the intermediate stage.

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