JP3618080B2 - Die bonding sheet sticking apparatus and die bonding sheet sticking method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sticking device which sticks a sheet functioning as a protective sheet at the time of dicing a semiconductor chip and also functioning as an adhesive for die bonding to the rear of a wafer. SOLUTION: This die bonding sheet sticking device is equipped with a wafer carrier which takes out a wafer stored in a wafer supplier and carries it, an alignment part which positions a wafer taken out of the wafer supplier, a sheet sticker which sticks a die bonding sheet equipped with a separation sheet and a base material having a heat sensitive adhesive layer to the rear of a wafer by heating it, and a sheet separator which separates the separation sheet of the die bonding sheet from the wafer where the die bonding sheet is stuck in the sheet sticker, and this sheet sticker is equipped with a cutting means which cuts the heat sensitive adhesive base material of the die bonding sheet into the external form of the wafer before sticking the die bonding sheet to the rear of the wafer.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a die bonding sheet that also functions as an adhesive material for die bonding when a semiconductor chip is die bonded to a lead frame after being diced in a manufacturing process of a small electronic component such as a semiconductor chip. The present invention relates to a die bonding sheet sticking apparatus and a method for sticking a die bonding sheet.
[0002]
[Prior art]
Conventionally, for example, in order to manufacture a semiconductor wafer such as silicon (hereinafter simply referred to as “wafer”), it is manufactured in a large-diameter disk shape, a circuit pattern is formed on the surface, and the surface is protected. After protecting the surface with the tape and grinding the back surface, the back surface of the wafer is attached to the ring frame via the adhesive sheet, and then the protective tape on the surface is peeled off. It is cut and separated (diced) into chips, and in this state, it is transferred to the following processes such as cleaning, drying, and die bonding.
[0003]
[Problems to be solved by the invention]
By the way, conventionally, as shown in FIG. 11, as a method of sticking the adhesive sheet on the back surface of the wafer, the wafer W is placed on the holding table 200, and the base sheet is placed on the back surface W <b> 3 of the wafer W. While sticking the adhesive sheet 202 which consists of 204 and the adhesive layer 206, the cutter 210 is cut | disconnected by rotating the cutter 210 along the external shape (outer periphery) W4 of the wafer W from the upper direction.
[0004]
Recently, however, there is a demand for increasingly thin semiconductor chips such as IC cards, and the demand for thin semiconductor chips from the conventional 300 μm to about 100 to 50 μm has increased in recent years. In order to obtain such a chip, an extremely thin wafer having the above thickness is required.
In the case of such an ultra-thin wafer, when the adhesive sheet 202 is cut with such a cutter 210, the outer peripheral portion W4 of the wafer W may be damaged or the wafer may be cracked.
[0005]
In addition, in order to prevent such wafer damage and wafer breakage, conventionally, in another process, the adhesive sheet is cut in advance into the outer shape of the wafer, and this is attached to the back surface of the wafer. Has been done.
Further, conventionally, an ultraviolet curable adhesive sheet is used as the adhesive sheet, and when the semiconductor chip cut and separated into a large number of chips is die-bonded (transferred) to the lead frame, the ultraviolet curable adhesive sheet is irradiated with ultraviolet rays. By doing so, the adhesive strength of the sheet is reduced, and die bonding is performed using the suction collet.
[0006]
In die bonding, an adhesive is separately applied to the lead frame, and a semiconductor chip is die bonded thereon.
However, in any case, such a separate process is required, a complicated process is required, and the cost is high.
The present invention provides a series of processes for attaching a die bonding sheet, which also functions as an adhesive for die bonding, to the back surface of a wafer when die bonding a semiconductor chip to a lead frame after dicing. Another object of the present invention is to provide a wafer die bonding sheet sticking apparatus that can be continuously and automatically performed without cracking.
[0007]
[Means for Solving the Problems]
The die bonding sheet sticking apparatus of the present invention includes a wafer supply unit that accommodates a plurality of wafers,
A wafer transfer unit comprising transfer means for taking out and transferring the wafer accommodated in the wafer supply unit;
An alignment unit that performs wafer positioning of the wafer taken out from the wafer supply unit via the wafer transfer unit of the wafer transfer unit;
The wafer positioned at a predetermined reference position in the alignment unit is transported through a transport unit, and the die bonding sheet made of a base material having a release sheet and a heat-sensitive adhesive layer is heated to heat the wafer. A sheet sticking part to be attached to the back surface of
A sheet peeling part provided with a sheet peeling means for peeling the release sheet of the die bonding sheet from the wafer to which the die bonding sheet is stuck in the sheet sticking part;
A cutting means for cutting the base material having the heat-sensitive adhesive layer of the die bonding sheet on the outer shape of the wafer before the sheet adhering portion adheres the die bonding sheet to the back surface of the wafer. It is characterized by providing.
[0008]
By configuring in this way, the wafer is taken out from the wafer cassette containing a plurality of wafers, the alignment for performing wafer positioning, and the die bonding sheet made of the base material having the release sheet and the heat-sensitive adhesive layer is attached to the back surface of the wafer. It is possible to continuously and automatically carry out a series of steps of sticking to the wafer, peeling the release sheet of the die bonding sheet, and storing the wafer in the wafer cassette.
[0009]
Moreover, it functions as an adhesive for die bonding when the semiconductor chip is die-bonded to the lead frame after being diced.
Therefore, unlike the conventional case, there is no need to apply an adhesive to the lead frame during die bonding, and the semiconductor chip can be picked up and picked up by the suction collet simply by heating the die bonding sheet. The heat-sensitive adhesive layer functions as an adhesive to the lead frame and can be directly thermocompression bonded.
[0010]
In addition, before sticking the die bonding sheet to the backside of the wafer, the die bonding sheet is cut with a cutter as before, since the substrate having the die bonding sheet's heat-sensitive adhesive layer is cut to the outer shape of the wafer. In doing so, there is no possibility that the outer peripheral portion of the wafer is damaged or the wafer is cracked, and it is not necessary to cut the die bonding sheet in advance in a separate process as in the prior art.
[0011]
Further, the die bonding sheet sticking apparatus of the present invention is a vertically movable cutting in which the cutting means rises from below the die bonding sheet and comes into contact with a base material having a heat-sensitive adhesive layer of the die bonding sheet. A blade device;
When the cutting blade device is raised to the upper position, the cutting and pressing device presses the die bonding sheet downward from above the die bonding sheet to cut the base material having the heat-sensitive adhesive layer of the die bonding sheet. It is characterized by providing.
[0012]
By comprising in this way, the base material which has the heat sensitive adhesive layer of the said die bonding sheet | seat can be cut | disconnected easily and correctly.
Further, in the die bonding sheet sticking apparatus of the present invention, the sheet sticking unit has a mount table provided with a heater for placing the wafer and heating the wafer,
The die bonding sheet is pressed downward from above the die bonding sheet heated by the mount table, and the back surface of the wafer placed on the mount table is attached to the thermosensitive adhesive layer of the die bonding sheet. It has a sticking press device which sticks to the substrate which has.
[0013]
By comprising in this way, a die-bonding sheet can be heated and the base material which has the said heat-sensitive adhesive layer can be easily and reliably stuck on the back surface of the said wafer.
Further, in the die bonding sheet sticking apparatus of the present invention, the mount table has an adsorption portion that protrudes upward at an outer peripheral portion of the mount table and adsorbs an outer peripheral portion of the surface of the wafer;
And an air blow space portion formed on an inner peripheral side of the suction portion and supporting the surface of the wafer upward from below with compressed air.
[0014]
As a result, the mounting table and the circuit pattern on the surface of the wafer do not come into contact with each other, so that the circuit pattern is not damaged, and the entire surface of the wafer is supported by the compressed air. The wafer is not cracked, broken or damaged when pressed downward by the sticking pressing device when sticking the sheet.
Further, in the die bonding sheet sticking device of the present invention, the sticking pressing device includes a fixed roller and a pressing movement roller,
The fixed roller holds the upstream side of the wafer of the die bonding sheet,
The pressing and moving roller is configured to adhere the die bonding sheet to the back surface of the wafer by moving to the downstream side.
[0015]
With this configuration, the fixed roller holds the upstream side of the wafer of the die bonding sheet, and the pressing movement roller moves to the downstream side, so that the air between the back surface of the wafer and the die bonding sheet is Since it is discharged from the downstream side, air is not trapped between the back surface of the wafer and the die bonding sheet, and the die bonding sheet can be reliably adhered to the back surface of the wafer.
[0016]
Moreover, the die bonding sheet sticking apparatus of the present invention includes the mount table on which the sheet peeling unit places the wafer,
The mounting table has a suction portion that protrudes upward at an outer periphery of the mount table and sucks the outer periphery of the surface of the wafer; and
And an air blow space portion formed on an inner peripheral side of the suction portion and supporting the surface of the wafer upward from below with compressed air.
[0017]
This prevents contact with the circuit pattern on the surface of the wafer, so that the circuit pattern is not damaged and the entire surface of the wafer is supported upward by the compressed air. When peeling the wafer, the wafer is not broken, broken or damaged.
Further, in the die bonding sheet sticking apparatus of the present invention, the sheet peeling means includes a fixed roller and a pair of peeling moving rollers,
The fixed roller holds the downstream side of the die bonding sheet,
The die bonding sheet is wound and sandwiched between the pair of peeling movement rollers, and the peeling movement roller moves to the upstream side of the die bonding sheet, whereby the peeling of the die bonding sheet from the wafer. The sheet is configured to peel off.
[0018]
Thereby, the release sheet of the die bonding sheet can be reliably and easily peeled from the wafer.
Furthermore, in the method for attaching the die bonding sheet of the present invention, the die bonding sheet comprising the release sheet and the base material having the heat-sensitive adhesive layer is attached to the back surface of the wafer. Before, a die bonding sheet cutting step of cutting a substrate having a heat-sensitive adhesive layer of the die bonding sheet on the outer shape of the wafer,
A die bonding sheet adhering step for adhering to the back surface of the wafer by heating the die bonding sheet cut into the outer shape of the wafer in the die bonding sheet cutting step;
And a sheet peeling step of peeling the release sheet of the die bonding sheet from the wafer to which the die bonding sheet is stuck in the die bonding sheet sticking step.
[0019]
By configuring in this way, the die bonding sheet is made of a base material having a release sheet and a heat-sensitive adhesive layer, so that it functions as a protective tape during dicing, and after being diced, a semiconductor chip is placed on the lead frame When die bonding is performed, it also functions as an adhesive for die bonding.
[0020]
Therefore, unlike the conventional case, there is no need to apply an adhesive to the lead frame during die bonding, and the semiconductor chip can be picked up and picked up by the suction collet simply by heating the die bonding sheet. The substrate having the heat-sensitive adhesive layer functions as an adhesive to the lead frame and can be directly thermocompression bonded.
[0021]
In addition, before sticking the die bonding sheet to the backside of the wafer, the die bonding sheet is cut with a cutter as before, since the substrate having the die bonding sheet's heat-sensitive adhesive layer is cut to the outer shape of the wafer. In doing so, there is no possibility that the outer peripheral portion of the wafer is damaged or the wafer is cracked, and it is not necessary to cut the die bonding sheet in advance in a separate process as in the prior art.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of a die bonding sheet sticking device of the present invention is described based on an accompanying drawing.
1 is a top view of the entire apparatus of the embodiment of the die bonding sheet sticking apparatus of the present invention, FIG. 2 is a view taken in the direction of arrows II-II of the die bonding sheet sticking apparatus of FIG. 1, and FIG. It is a III direction arrow line view of 1 die-bonding sheet sticking apparatuses.
[0023]
In FIG. 1, reference numeral 1 denotes a semiconductor wafer die bonding sheet sticking apparatus (hereinafter simply referred to as "sticking apparatus 1") of the present invention as a whole.
As shown in FIG. 1, the bonding apparatus 1 includes a wafer supply unit 10 that stores a plurality of wafers W, a wafer transfer unit 20 that transfers a wafer W stored in the wafer supply unit 10, and a wafer transfer unit 20. As shown in FIG. 4, the alignment unit 30 that positions the wafer W taken out from the wafer supply unit 10 and the back surface W3 of the wafer W positioned by the alignment unit 30 (that is, the surface on which the circuit pattern is not formed). Then, a sheet (hereinafter referred to as “die bonding sheet 2”) constituted by pasting a release sheet on both surfaces of a base material (hereinafter referred to as “heat-sensitive adhesive base material 7”) having a heat-sensitive adhesive layer on both sides is pasted. A sheet bonding unit 40 and a wafer W on which the die bonding sheet 2 is bonded by the sheet bonding unit 40 are used to peel the release sheet 4 (4A) of the die bonding sheet 2 from. And a preparative peeling unit 50.
[0024]
As such a die bonding sheet 2, for example, the base material 6 can be made of a PET (polyethylene terephthalate) resin and the heat-sensitive adhesive layer 5 can be made of a polyimide resin. The substrate is not limited to this, and any substrate having a heat-sensitive adhesive layer may be used.
As shown in FIGS. 1 and 3, in the wafer supply unit 10, a wafer carrier (wafer transfer container) 12 or a wafer supply box (not shown) in which the wafers W are stacked and stored is a lift drive motor 14. By a driving device such as a ball screw mechanism 16, the wafer supply unit 10 is detachably disposed so as to be movable up and down. A plurality of shelves (not shown) having convex portions formed in the wafer carrier 12 contain a plurality of wafers W in each stage of the shelves. In FIG. 3, two upper and lower wafer carriers 12 that are used alternately are shown in order to continuously operate the sticking apparatus 1.
[0025]
Further, although not shown, a wafer detection sensor (light transmission type or light reflection type sensor or the like) is attached to the wafer supply unit 10, and each stage of the wafer W is moved by the sensor while moving the wafer carrier 12 up and down. The position, the number of sheets, etc. can be detected. The wafer supply unit 10 may be a wafer supply box in which buffer sheets are laid and stacked between wafers in order to protect the circuit surface.
[0026]
As shown in FIG. 1, the wafer transfer unit 20 is a robot having a multi-axis movable arm 22, and the movable arm 22 moves the wafers W in the order of arrows (1) to (4) shown in FIG. 1. The wafer supply unit 10, the alignment unit 30, the mount table 42, and the sheet peeling unit 50 can be transported.
[0027]
A suction member 24 connected to a vacuum source (not shown) is provided at the tip of the movable arm 22, and the wafer W is sucked and fixed by a negative pressure by the suction member 24 that sucks the wafer W on the movable arm 22. It can be done.
The wafer transfer unit 20 configured as described above detects the step position, the number, etc. of the wafers W of the wafer carrier 12 of the wafer supply unit 10 and moves the wafer transfer unit 20 up and down based on the results. The wafer W accommodated in the shelf of the wafer carrier 12 is picked up and taken out by the suction member 24 of the movable arm 22 as indicated by an arrow (1) shown in FIG.
[0028]
Then, the wafer W taken out from the wafer supply unit 10 is sucked and fixed to the suction member 24 at the tip of the movable arm 22 with the circuit surface facing upward, and on the turntable 32 of the alignment unit 30 for positioning the wafer by the movable arm 22. (Arrow (2) in FIG. 1).
In the alignment unit 30, although not shown, a sensor (not shown) is formed by rotating an orientation flat (orientation flat) part or V notch part in which a peripheral part is linearly formed as a reference part formed on the wafer W by rotating the wafer W. , And alignment (positioning) is performed.
[0029]
In this way, the wafer W that has been aligned by the alignment unit 30 is released from the suction of the turntable 32, is sucked and fixed on the movable arm 22, and is further attached by a reversing mechanism (not shown) attached to the movable arm 22. The wafer W is turned upside down 180 °, and the wafer W is transferred to the mounting table 42 of the wafer heating and bonding unit 45 of the sheet bonding unit 40 for bonding the die bonding sheet 2 to the back surface of the wafer W with the back surface of the wafer W facing up. (Arrow (3) in FIG. 1).
[0030]
As shown in FIGS. 1, 2, and 5, the sheet sticking unit 40 includes a wafer heating sticking unit 45 that receives the aligned wafer W transported by the movable arm 22, and a sheet feeding that feeds the die bonding sheet 2. The feeding unit 44 includes a sheet cutting unit 46 that cuts the die bonding sheet 2, and an adhesion pressing unit 48 that adheres the die bonding sheet 2 to the back surface of the wafer W.
[0031]
In the wafer heating and sticking unit 45, the wafer W transported by the movable arm 22 is transferred onto the mount table 42 and is sucked and held. 1, 2, and 5, the mount table 42 is moved along the guide rail 60 by a drive mechanism such as a cylinder mechanism (not shown) as indicated by an arrow A in the standby position 41 (wafer W transfer). It is possible to move between the mounting position (dotted line position in FIG. 5) and the sticking position (solid line position in FIG. 5).
[0032]
As shown in FIGS. 2 and 5, the sheet feeding unit 44 includes a die bonding sheet 2 wound around a feeding roller 62, and the die bonding sheet 2 fed from the feeding roller 62 is guided to a guide roller 64, It passes through the peeling roller 66 and the tension roller 68 and reaches the cutting / sticking position 70.
At this time, the release sheet 4B of the die bonding sheet 2 is abruptly folded back by the release roller 66 to be released from the die bonding sheet 2, and is wound around the release material winding portion 75 via the guide roller 72. It has become.
[0033]
As shown in FIG. 5, the die bonding sheet 2 that has reached the cutting / sticking position 70 has a cutting blade device 76 (FIG. 9) configured to be movable up and down along the guide rail 74 at the sheet cutting portion 46. Ascending as indicated by an arrow B from below the die bonding sheet 2, the cutting blade 78 formed in the outer shape of the wafer W is raised to a position where it contacts the heat-sensitive adhesive substrate 7 of the die bonding sheet 2.
[0034]
At this time, as shown in FIG. 6 and FIG. 7, the sheet cutting and pressing device 82 that can move up and down along the guide rail 80 moves downward, and the cutting and pressing roller 84 provided below the guide pressing device 82 moves the guide rail 86. The die bonding sheet 2 is pressed downward from above the die bonding sheet 2 by moving in the direction C along the direction perpendicular to the feeding direction of the die bonding sheet 2 along The adhesive adhesive base material 7 is cut into the outer shape of the wafer W so that a cut 88 is formed (FIG. 9). At this time, the exact position of the cut 88 is adjusted by adjusting the rising amount of the cutting blade device 76 by driving the cylinder 90 by a control device (not shown).
[0035]
At this time, the mount table 42 is at the standby position 41 (dotted line position in FIG. 5).
Thus, after the cut 88 is formed in the heat-sensitive adhesive base material 7 of the die bonding sheet 2 in the outer shape of the wafer W, the cutting blade device 76 moves downward, and the sheet cutting and pressing device 82 is raised, Each moves to the standby position. At this time, the cutting and pressing roller 84 also returns to the original position.
[0036]
In this state, the mount table 42 at the standby position 41 (dotted line position in FIG. 5) moves to the sticking position (solid line position in FIG. 5) as shown by an arrow A in FIGS.
As shown in FIG. 8, the mount table 42 has an outer peripheral portion protruding upward, and an adsorption portion 92 that adsorbs the outer peripheral portion W <b> 1 of the surface of the wafer W is formed. An air blow space portion 94 is formed on the inner peripheral side of the.
[0037]
The suction portion 92 is formed with a width of about 3 mm from the outer diameter of the wafer W and abuts on a portion of the wafer W where the circuit pattern is not formed, so that it does not affect the circuit pattern of the wafer W. It has become. The suction portion 92 is connected to a vacuum source (not shown) and sucks the outer peripheral portion W1 of the wafer W by the action of negative pressure.
[0038]
The air blow space 94 is supplied with compressed air P at a constant pressure via an air supply pipe 96 connected to an air supply source (not shown), and the surface W2 of the wafer W is entirely moved upward at a constant pressure. (Arrow P in FIG. 8).
In this state, the mount table 42 moves to the attachment position (solid line position in FIG. 5), and as shown in FIG. 8, on the back surface W3 of the wafer W (that is, the surface on which the circuit pattern is not formed) The die W is brought into contact with the heat-sensitive adhesive substrate 7 of the die bonding sheet 2 in which the cut 88 is formed in the outer shape of the wafer W. At this time, the exact position of the back surface W3 of the wafer W is adjusted by adjusting the rising amount of the mount table 42 by driving the cylinder 98 by a control device (not shown).
[0039]
The mount table 42 is provided with a heater 43, and the heat-sensitive adhesive layer 5 of the die bonding sheet 2 is heated via the wafer W, so that the adhesiveness is increased. Such a temperature is set to a temperature that does not affect the performance of the wafer W, although it depends on the type of the heat-sensitive adhesive.
In this state, the die pressing sheet 48 presses the die bonding sheet 2 downward from above the die bonding sheet 2 by the sticking pressing part 48, and the back surface W 3 of the wafer W placed on the mount table 42 is heated. The adhesive adhesive substrate 7 is attached.
[0040]
That is, as shown in FIGS. 2, 5, and 8, the sticking pressing portion 48 includes a fixed roller 102 and a pressure moving roller 104 disposed on the downstream side thereof. While holding the upstream side of the wafer W of the die bonding sheet 2 and the pressing movement roller 104 pressing the die bonding sheet 2 downward from above, it moves downstream in the direction of arrow D in FIG. The heat-sensitive adhesive substrate 7 of the die bonding sheet 2 is adhered to the back surface W3 of W (FIG. 8).
[0041]
In this way, the fixed roller 102 holds the upstream side of the wafer W of the die bonding sheet 2, and the pressing movement roller 104 moves to the downstream side, so that the back surface W 3 of the wafer W and the die bonding sheet 2 are thermally bonded. Since air between the base material 7 is discharged from the downstream side, air is not trapped between the back surface W3 of the wafer W and the heat-sensitive adhesive base material 7 of the die bonding sheet 2, and the wafer W is reliably The heat-sensitive adhesive base material 7 of the die bonding sheet 2 can be adhered to the back surface W3.
[0042]
At this time, since the entire surface W2 of the wafer W is supported upward by the air, when the pressing moving roller 104 presses the sticking pressing portion 48 by sticking the die bonding sheet 2 downward. The wafer W is not broken, broken or damaged.
As described above, after the heat-sensitive adhesive substrate 7 of the die bonding sheet 2 is adhered to the back surface W3 of the wafer W by the adhesion pressing part 48, the adsorption of the adsorption part 92 of the mount table 42 is released and the mount The table 42 is moved from the sticking position (solid line position in FIG. 5) to the standby position 41 (dotted line position in FIG. 5), and a new wafer W that has been aligned again by the alignment unit 30 is transferred to the wafer transfer unit. It is conveyed to the mount table 42 by 20 movable arms 22.
[0043]
On the other hand, in the state where the heat-sensitive adhesive base material 7 of the die bonding sheet 2 pre-cut is attached to the back surface W3 of the wafer W, the die bonding sheet 2 is peeled from the downstream side while the wafer W is attached. It is conveyed to the section 50.
In the sheet peeling part 50, the peeling sheet 4 </ b> A of the die bonding sheet 2 is peeled from the wafer W to which the part of the die bonding sheet 2 on which the heat-sensitive adhesive base material 7 is pre-cut is stuck in the sheet sticking part 40. .
[0044]
That is, as shown in FIG. 2 and FIG. 10, the die bonding sheet 2 is wound and sandwiched between the pair of peeling moving rollers 108 and 110 in the sheet peeling unit 50 as shown in FIGS. 2 and 10. It is guided by the fixed roller 112 and is taken up by the residue take-up roller 114.
Further, as shown in FIGS. 1, 2 and 10, the die bonding sheet 2 is provided with a mount table 116 having the same structure as the mount table 42 of the sheet adhering portion 40. Along with this, it is configured to be movable up and down (F direction) by a driving mechanism such as the cylinder mechanism 120.
[0045]
That is, the mount table 116 is formed on the inner peripheral side of the suction portion 122 and the suction portion 122 that sucks the outer peripheral portion W1 of the surface of the wafer W, with the outer peripheral portion of the mount table 116 protruding upward. An air blow space portion 126 is provided that supports the surface W2 from above through compressed air P from above via an air supply pipe 124. However, the mount table 116 is not provided with a heater.
[0046]
Therefore, in the sheet peeling part 50, it conveys to the downstream sheet peeling part 50 in the state in which the thermosensitive adhesive base material 7 of the die bonding sheet 2 was stuck to the back surface W3 of the wafer W, as shown in FIG. With respect to the die bonding sheet 2 thus mounted, the mount table 116 rises in the direction of arrow F in FIG. 10, and the outer peripheral portion W 1 of the wafer W is sucked by the suction portion 122 of the mount table 116. Then, the compressed air P is supplied at a constant pressure through an air supply pipe 124 connected to an air supply source (not shown), and the surface W2 of the wafer W is entirely supported at a constant pressure.
[0047]
In this state, as indicated by an arrow E in FIG. 10, the die bonding sheet sandwiched between the pair of peeling movement rollers 108 and 110 by moving the pair of peeling movement rollers 108 and 110 upstream as the sheet peeling means. 2 shows a heat-sensitive adhesive group in which the release sheet 4A is pre-cut in a state where the heat-sensitive adhesive base material 7 is adhered to the back surface W3 of the wafer W by a cut (pre-cut) 88, as shown by a dotted line in FIG. The material 7 is peeled off together with the cutting residue. The peeled release sheet 4 </ b> A is guided by the fixed roller 112 and taken up by the take-up roller 114.
[0048]
At the time of peeling, since the entire surface W2 of the wafer W is supported upward by the compressed air P, the wafer W is cracked, broken, or damaged when the peeling sheet 4A of the die bonding sheet 2 is peeled off. There is nothing to do.
After the peeling operation is completed, the mount table 116 is lowered in the direction of arrow F in FIG. 10, the suction of the suction unit 122 is released, and the wafer W is suction-fixed on the movable arm 22 and the wafer supply unit 10 is accommodated in a shelf of the wafer carrier 12, or a buffer sheet for protecting the circuit surface is laid between the wafers in a wafer storage box (not shown) while being stacked and stored in a wafer storage box for storing the wafer W. It may be.
[0049]
The above cycle is repeated.
In addition, the wafer W in which the heat-sensitive adhesive base material 7 of the die bonding sheet 2 is attached to the back surface W3 of the wafer W in this way is transferred to each process such as a dicing process, cleaning, drying, and die bonding.
[0050]
【The invention's effect】
According to the present invention, from the wafer cassette containing a plurality of wafers, the wafer is taken out, the alignment for performing wafer positioning, the back surface of the wafer of the die bonding sheet comprising the release sheet and the substrate having the heat-sensitive adhesive layer It is possible to continuously and automatically carry out a series of steps of sticking to the wafer, peeling the release sheet of the die bonding sheet, and storing the wafer in the wafer cassette.
[0051]
Moreover, since the die bonding sheet is a sheet provided with a release sheet and a base material having a heat-sensitive adhesive layer, it functions as a protective tape during dicing, and after dicing, a semiconductor chip is placed on the lead frame. When die bonding is performed, it also functions as an adhesive for die bonding.
Therefore, unlike the conventional case, there is no need to apply an adhesive to the lead frame at the time of die bonding, and at the time of die bonding, the semiconductor chip is picked up by the suction collet simply by heating the die bonding sheet. In addition, the substrate having the heat-sensitive adhesive layer of the die bonding sheet functions as an adhesive to the lead frame and can be directly thermocompression bonded.
[0052]
Furthermore, since the base material having the heat-sensitive adhesive layer of the die bonding sheet is cut (pre-cut) on the outer shape of the wafer before the base material having the heat-sensitive adhesive layer of the die bonding sheet is attached to the back surface of the wafer, When cutting the die bonding sheet with a cutter like this, there is no risk that the outer periphery of the wafer will be damaged or the wafer will break, and the die bonding sheet is cut in advance in a separate process as in the past. It is an extremely excellent invention that has a number of unique and remarkable effects.
[Brief description of the drawings]
FIG. 1 is a top view of an entire apparatus of an embodiment of a die bonding sheet sticking apparatus of the present invention.
2 is a view taken in the direction of arrows II-II of the die bonding sheet sticking apparatus of FIG.
3 is a view in the direction of arrow III of the die bonding sheet sticking apparatus of FIG.
FIG. 4 is a partially enlarged cross-sectional view of a die bonding sheet used in the present invention.
FIG. 5 is a schematic perspective view for explaining the operation of the die bonding sheet sticking apparatus of the present invention.
FIG. 6 is a front view of a sheet cutting portion of the die bonding sheet sticking apparatus of the present invention.
7 is a side view of the sheet cutting portion of FIG. 6. FIG.
FIG. 8 is a schematic cross-sectional view for explaining the operation of the sticking pressing portion of the die bonding sheet sticking apparatus of the present invention.
FIG. 9 is a schematic cross-sectional view illustrating the operation of the sheet cutting unit of the die bonding sheet sticking apparatus of the present invention.
FIG. 10 is a schematic cross-sectional view for explaining the operation of the sheet peeling portion of the die bonding sheet sticking apparatus of the present invention.
FIG. 11 is a schematic cross-sectional view illustrating a conventional method for attaching an adhesive sheet.
[Explanation of symbols]
1 Adhering device (die bonding sheet adhering device)
2 Die bonding sheet
4A, 4B release sheet
5 Heat-sensitive adhesive layer
6 Base material
7 Heat-sensitive adhesive substrate (substrate having a heat-sensitive adhesive layer)
10 Wafer supply section
12 Wafer carrier
14 Lifting drive motor
16 Ball screw mechanism
20 Wafer transfer part
22 Movable arm
24 Suction member
30 Alignment part
32 Turntable
40 Sheet sticking part
42, 116 Mount table
44 Sheet feeding section
45 Wafer heating sticking part
46 Sheet cutting part
48 Adhesion pressing part
50 Sheet peeling part
60 guide rail
62 Feeding roller
64 Guide roller
66 Peeling roller
68 Tension roller
70 Cutting and sticking position
72 Guide roller
75 Release material winding part
76 Cutting blade device
78 Cutting blade
80 guide rail
82 Sheet cutting and pressing device
84 Cutting pressure roller
86 Guide rail
90 cylinders
92 Adsorption part
94, 126 Air blow space
96 Air supply pipe
98 cylinders
102 Fixed roller
104 Press moving roller
108, 110 Peeling movement roller (sheet peeling means)
112 Fixed roller (sheet peeling means)
114 Waste winding part
118 Guide rail
120 Cylinder mechanism
122 Adsorption part
124 Air supply pipe
200 holding table
202 Adhesive sheet
204 Base sheet
206 Adhesive layer
210 cutter
W wafer
W1 outer periphery
W2 surface
W3 back side

Claims (8)

A wafer supply unit for accommodating a plurality of wafers;
A wafer transfer unit comprising transfer means for taking out and transferring the wafer accommodated in the wafer supply unit;
An alignment unit that performs wafer positioning of the wafer taken out from the wafer supply unit via the wafer transfer unit of the wafer transfer unit;
The wafer positioned at a predetermined reference position in the alignment unit is transported through a transport unit, and the die bonding sheet made of a base material having a release sheet and a heat-sensitive adhesive layer is heated to heat the wafer. A sheet sticking part to be attached to the back surface of
A sheet peeling part provided with a sheet peeling means for peeling the release sheet of the die bonding sheet from the wafer to which the die bonding sheet is stuck in the sheet sticking part;
A cutting means for cutting the base material having the heat-sensitive adhesive layer of the die bonding sheet on the outer shape of the wafer before the sheet adhering portion adheres the die bonding sheet to the back surface of the wafer. A die bonding sheet sticking device comprising: A cutting blade device capable of moving up and down, wherein the cutting means rises from below the die bonding sheet and contacts the base material having the heat-sensitive adhesive layer of the die bonding sheet;
When the cutting blade device is raised to the upper position, the die bonding sheet is pressed downward from above the die bonding sheet to cut only the base material having the heat-sensitive adhesive layer of the die bonding sheet. The die bonding sheet sticking apparatus according to claim 1, further comprising a cutting and pressing device. A mounting table provided with a heater for placing the wafer and heating the wafer;
The die bonding sheet is pressed downward from above the die bonding sheet heated by the mount table, and the back surface of the wafer placed on the mount table is placed on the thermosensitive adhesive layer of the die bonding sheet. The die-bonding sheet sticking apparatus according to claim 1, further comprising a sticking pressing device that sticks to a base material having an adhesive. The mounting table has a suction portion that has an outer peripheral portion of the mount table that protrudes upward and sucks the outer peripheral portion of the surface of the wafer; and
The die bonding sheet sticking apparatus according to claim 3, further comprising: an air blow space portion formed on an inner peripheral side of the suction portion and supporting a surface of the wafer upward from below by compressed air. The sticking pressing device includes a fixed roller and a pressing movement roller,
The fixed roller holds the upstream side of the wafer of the die bonding sheet,
The die bonding sheet according to any one of claims 3 to 4, wherein the pressing and moving roller is configured to adhere the die bonding sheet to a back surface of the wafer by moving to the downstream side. Sticking device. The sheet peeling unit includes the mount table on which the wafer is placed,
The mounting table has a suction portion that protrudes upward at an outer periphery of the mount table and sucks the outer periphery of the surface of the wafer; and
6. The die bonding according to claim 1, further comprising: an air blow space portion that is formed on an inner peripheral side of the suction portion and supports the surface of the wafer from above under compressed air. Sheet sticking device. The sheet peeling means includes a fixed roller and a pair of peeling moving rollers,
The fixed roller holds the downstream side of the die bonding sheet,
The die bonding sheet is wound and sandwiched between the pair of peeling movement rollers, and the peeling movement roller moves to the upstream side of the die bonding sheet, so that the peeling sheet of the die bonding sheet is removed from the wafer. The die bonding sheet sticking apparatus according to any one of claims 1 to 6, wherein the die bonding sheet sticking apparatus is configured to peel off. A die bonding sheet comprising a release sheet and a substrate having a heat sensitive adhesive layer is bonded to the outer surface of the wafer before the die bonding sheet is attached to the back surface of the wafer. The die bonding sheet cutting step for cutting only the base material having the adhesive layer,
A die bonding sheet adhering step for adhering to the back surface of the wafer by heating the die bonding sheet cut into the outer shape of the wafer in the die bonding sheet cutting step;
Wherein the die bonding sheet sticking step the wafer in which the die bonding sheet is attached, the die bonding sheet sticking method which comprises a sheet peeling step of peeling off the release sheet of the die bonding sheet.

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