JP2004172356A - Method for manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for preventing a deviation of a semiconductor chip and for highly precisely bonding the chip. <P>SOLUTION: A face adsorbing the semiconductor chip 5 of a collet 2c is disposed at a tip of a bonding head 2b arranged in a bonding processing part of a flip chip bonder, and has a function for adsorbing and holding the semiconductor chip 5. The face is coated with a coating material 2d having a friction coefficient higher than a metal constituting the collet 2c, ceramic, for example. Thus, the deviation of the semiconductor chip 5 from the collet 2c when the semiconductor chip 5 is joined with an interposer 3A. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a semiconductor device manufacturing technique, and is particularly effective when applied to the manufacture of a semiconductor device including a step of die bonding to an interposer or a mounting substrate, which is a chip supporting member for supporting a semiconductor chip on which an integrated circuit is formed. Technology.
[0002]
[Prior art]
A flip chip bonder is known as a semiconductor manufacturing apparatus for bonding a semiconductor chip to a chip supporting member by flip chip mounting. Chip bonding using this flip chip bonder is performed, for example, as follows (see Non-Patent Document 1).
[0003]
First, a semiconductor chip is picked up by a flip head and inverted, and then the semiconductor chip is sucked by a collet attached to a bonding head. Subsequently, after correcting the positional relationship between the semiconductor chip and the chip support member, the collet is lowered to make the bump electrodes provided on the main surface of the semiconductor chip and the pad electrodes of the chip support member directly adhere to each other. The semiconductor chip and the chip supporting member are joined by applying heat or the like and pressure bonding.
[0004]
[Non-patent document 1]
“2001 Edition Latest Semiconductor Assembly / Packaging Technology”, Press Journal, P.S. 103-109
[0005]
[Problems to be solved by the invention]
However, the present inventor has studied and found that the following problems occur when joining the semiconductor chip and the chip supporting member.
[0006]
A collet for adsorbing a semiconductor chip is usually made of metal, and its chip adsorbing surface is processed flat so as not to damage the back surface of the semiconductor chip. However, if there is variation in the height of the bump electrodes of the semiconductor chip, the semiconductor chip tilts when the bump electrodes of the semiconductor chip and the pad electrodes of the chip support member are pressed, and the collet has a relatively small frictional force. Since the chip is made of metal and its chip suction surface is flat, the semiconductor chip is displaced from the collet by the force acting in the rotating direction, and the target bonding accuracy cannot be obtained.
[0007]
When the diameter of the vacuum suction hole provided in the collet is increased to increase the suction force, the area of the chip suction surface is reduced, and the semiconductor chip is likely to be displaced. It becomes.
[0008]
By making the chip suction surface of the collet rough, displacement of the semiconductor chip can be prevented. However, by repeating the bonding operation, the metal constituting the bump electrode formed on the semiconductor chip, for example, gold (Au) adheres to the chip suction surface to form a projection, and the bump electrode of the semiconductor chip and the chip supporting member are formed. When the pressure is applied to the pad electrode, the protrusion hits the semiconductor chip, and the semiconductor chip is broken.
[0009]
Although the protrusions can be removed by a cleaning mechanism, the throughput of the flip chip bonder is reduced, and the mechanism of the flip chip bonder is complicated.
[0010]
An object of the present invention is to provide a technique capable of performing high-precision chip bonding while preventing a semiconductor chip from shifting.
[0011]
The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.
[0012]
[Means for Solving the Problems]
The following is a brief description of an outline of typical inventions disclosed in the present application.
[0013]
The present invention includes a step of arranging a chip supporting member on a mount stage, a step of adsorbing a semiconductor chip to a collet, and a step of pressing the semiconductor chip adsorbed to the collet to a chip supporting member. The surface for adsorbing the chip is coated with a material having a higher coefficient of friction than the material forming the collet.
[0014]
The present invention includes a step of arranging a chip supporting member on a mount stage, a step of adsorbing a semiconductor chip to a collet, and a step of pressing the semiconductor chip adsorbed to the collet to a chip supporting member. A sheet is interposed between the chip and the chip.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all the drawings for describing the embodiments, components having the same function are denoted by the same reference numerals, and the repeated description thereof will be omitted.
[0016]
(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a flip chip bonder according to the first embodiment, and FIG. 2 is a schematic diagram illustrating an enlarged bonding processing unit of the flip chip bonder.
[0017]
A flip chip bonder is a manufacturing apparatus that performs bonding of a semiconductor chip (hereinafter, simply referred to as a chip) to a chip supporting member when assembling a CSP (Chip Size Package), for example, and performs bonding between the chip and the chip supporting member. Things.
[0018]
In the bonding section 2 of the flip chip bonder 1, a mount stage 2a, which is a stage for supporting the chip supporting member 3, and a bonding head 2b provided above and opposed to the mount stage 2a are installed. The chip 5 picked up from the semiconductor wafer 4 is sucked and held by the collet 2c at the tip of the bonding head 2b. The surface of the collet 2c for adsorbing the chip 5 is coated with a coating material 2d having a higher coefficient of friction than the metal constituting the collet 2c, for example, ceramic.
[0019]
The mount stage 2a and the bonding head 2b apply a load, heat, and the like to the chip support member 3 and the chip 5 to join them. The mount stage 2a is mounted on an XY table 6 that is movable in the XY directions, and is guided by a Z movement mechanism, thereby being movable in the XYZ directions. The bonding head 2b is installed so as to be rotatable and movable in the XYZ directions.
[0020]
Further, in the bonding section 2, for example, an optical probe 2e equipped with an optical system having two upper and lower visual fields is arranged between the chip 5 held by the collet 2c and the chip supporting member 3 mounted on the mount stage 2a. It is provided movably as possible. The information captured by the upper and lower two-field optical system is processed by the recognition unit 7, and the positions of the recognition mark of the chip supporting member 3 and the recognition mark of the chip 5 are obtained based on the information.
[0021]
The wafer setting section 8 picks up a wafer support 8a on which the diced semiconductor wafer 4 is placed, and picks up the chips 5 to be bonded from the diced semiconductor wafer 4 mounted on the wafer support 8a. And a flip head 8b for turning over the chip 5 turned over and transferring it to the collet 2c. In the wafer setting section 8, pick-up of the chips 5 from the diced semiconductor wafer 4 and transfer of the chips 5 to the bonding head 2b are performed.
[0022]
The transfer of the semiconductor wafer 4 to the wafer setting unit 8 is performed by the wafer lifter 9. The chip support member 3 is sent out to the transport unit 10 by the loader 11, and the chip support member 3 after chip bonding is accommodated in the unloader 12.
[0023]
FIG. 3 is a cross-sectional view of a main part of a tape-type CSP to which chip bonding has been performed using the flip chip bonder according to the first embodiment. Here, a case where a sheet-like thin-film wiring board is used as an example of the chip supporting member will be described. Therefore, the flip chip bonder bonds a chip to a sheet-like wiring board which is a chip supporting member.
[0024]
The CSP 13 has a small external size slightly larger than that of the chip 5, and has a plurality of pads, which are surface electrodes, on the outer peripheral portion of the main surface 5 a (the surface on which the semiconductor integrated circuit is formed) of the chip 5. The case where 5b is arranged will be described. The place where the pad 5b is provided is not particularly limited, and may be an outer peripheral portion of the main surface 5a of the chip 5, an inner side (for example, a center pad arrangement), or both. It may be.
[0025]
The configuration of the CSP 13 is a thin film tape having a lead 3a connected to the pad 5b of the chip 5 and having a wiring 3b connected to the lead 3a and also connected to a bump electrode 14 as an external terminal. The interposer 3A, the elastomer 15 which is an elastic member disposed between the interposer 3A and the chip 5, and the pad 5b and the lead 3a formed by sealing the resin in the opening 3c of the interposer 3A. And a sealed portion 16.
[0026]
Here, the thin-film tape-shaped interposer 3A is formed of, for example, a polyimide-based film base material. The sealing material used for the sealing portion 16 is, for example, an epoxy-based thermosetting resin or the like, and resin sealing is performed by molding or potting.
[0027]
Next, a chip bonding method of the tape-type CSP according to the first embodiment will be described in the order of steps with reference to FIGS.
[0028]
First, after a semiconductor integrated circuit is formed on the main surface of the semiconductor wafer 4 according to a well-known manufacturing process, a wafer inspection is performed for each of a plurality of chips 5 partitioned by scribe lines, and non-defective products and defective products are selected.
[0029]
Next, as shown in FIG. 4, after grinding the back surface of the semiconductor wafer 4 with a grinder and finishing polishing by wet etching, a dicing tape 17 is adhered to the back surface of the semiconductor wafer 4 and a peripheral portion of the dicing tape 17 is formed. Is bonded and fixed to the carrier jig 18. Next, the semiconductor wafer 4 is diced using a diamond blade 19 or the like, so that the chips 5 are singulated. At this time, the dicing tape 17 is not cut completely in order to adhere the individual chips 5 to the dicing tape 17.
[0030]
Next, as shown in FIG. 5, the diced semiconductor wafer 4 is set on the wafer support 8a of the wafer setting section 8 by the wafer lifter 9. The semiconductor wafer 4 is divided into individual chips 5. Subsequently, the chip 5 on which the chip bonding is performed is vacuum-adsorbed by the flip head 8b to separate the chips 5 from the dicing tape 17 one by one. The chip 5 peeled off from the dicing tape 17 is moved to the bonding processing unit 2 with its front and back reversed while being sucked and held by the flip head 8b.
[0031]
Thereafter, as shown in FIG. 6, the back surface 5c of the chip 5 is sucked and held by the collet 2c provided at the tip of the bonding head 2b, and the chip 5 is made to wait above the mount stage 2a. The surface of the collet 2c on which the chip 5 is sucked is coated with a coating material 2d having a higher coefficient of friction than the metal forming the collet 2c, thereby preventing the chip 5 from shifting. On the other hand, the interposer 3A is sent out from the loader 11 to the transport section 10, and the interposer 3A is arranged on the mount stage 2a of the bonding section 2 from the transport section 10 (see FIG. 1).
[0032]
Further, an optical system capable of imaging the recognition mark of the chip 5 and the recognition mark of the interposer 3A is mounted between the chip 5 supported by the collet 2c and the interposer 3A mounted on the mount stage 2a so as to face the chip 5. Optical probe 2e is arranged. Subsequently, the position information of the recognition mark of the chip 5 and the interposer 3A is obtained using the optical probe 2e, and the positions of the chip 5 and the interposer 3A are determined based on the amount of displacement between the chip 5 and the interposer 3A obtained from the position information. to correct.
[0033]
Next, as shown in FIG. 7, the chip 5 and the interposer 3A are aligned based on the corrected positions of the chip 5 and the interposer 3A, and a load is applied to the chip 5 and the interposer 3A by the mount stage 2a and the bonding head 2b. The two are joined by applying heat or heat, and chip bonding is performed. Here, since the chip 5 is held by the collet 2c via the coating material 2d having a relatively high coefficient of friction, the displacement of the chip 5 from the collet 2c caused when the chip 5 and the interposer 3A are joined to each other. Can be prevented.
[0034]
After the chip mounting, the interposer 3A is sent to the unloader 12 and stored therein (see FIG. 1).
[0035]
Thereafter, lead bonding, molding, ball attachment, selection and marking are performed, and the CSP 13 shown in FIG. 3 is substantially completed. In the lead bonding, the pads 5b of the chip 5 and the leads 3a of the interposer 3A are connected using an inner lead bond or the like. In the molding, the pad 5b and the lead 3a of the chip 5 are sealed with a resin by potting or the like using a sealing resin, thereby forming a sealing portion 16. In the ball attachment, a predetermined number of bump electrodes 14 are formed by mounting one solder ball as an external terminal on each of lands at predetermined positions connected to the wiring 3b of the interposer 3A.
[0036]
In the first embodiment, an example in which the present invention is applied to the chip bonding of the tape-type CSP 13 has been described. However, the present invention can also be applied to a carrier-type CSP or a bare chip.
[0037]
FIG. 8 is a cross-sectional view of a main part of a carrier-type CSP to which chip bonding has been performed using the flip chip bonder according to the first embodiment.
[0038]
Pad electrodes 21 and 22 are formed on the upper and lower surfaces of the interposer 3B, respectively. The interposer 3B is made of, for example, a ceramic material such as alumina, borosilicate glass or mullite, or a build-up wiring board. The pad electrodes 21 and 22 are electrically connected to each other by an internal wiring formed of, for example, tungsten (W) or molybdenum (Mo) formed inside the interposer 3B. The internal wiring may be a multilayer wiring connected by through-holes.
[0039]
A bump electrode 23 is joined to the pad electrode 21 on the lower surface of the interposer 3B. An underfill resin 24 is provided between the chip 5 and the interposer 3B to mechanically reinforce the bump electrodes 23 and improve the connection life. The underfill resin 24 is made of, for example, an epoxy resin. The bump electrode 23 is connected to a base electrode (not shown) formed on the main surface side of the chip 5. That is, the chip 5 is chip-bonded to the pad electrode 21 of the interposer 3B via the bump electrode 23.
[0040]
FIG. 9 is a cross-sectional view of a main part of a bare chip on which chip bonding has been performed using the flip chip bonder according to the first embodiment.
[0041]
The chip 5 is bonded to the pad electrode 25 formed on the upper surface of the mounting substrate 3C via a bump electrode 26 made of, for example, gold or solder, and an underfill resin is provided between the chip 5 and the mounting substrate 3C. 27 are filled. By providing the underfill resin 27, the stress caused by the difference in the thermal expansion coefficient between the mounting board 3C and the chip 5 can be borne by the entire chip 5, so that the stress concentration at the base of the bump electrode 26 is reduced. be able to.
[0042]
As described above, according to the first embodiment, the surface of the collet 2c provided at the tip of the bonding head 2b for adsorbing the chip 5 is coated with the coating material 2d having a higher friction coefficient than the metal forming the collet 2c. By doing so, it is possible to prevent the chip 5 from being displaced from the collet 2c when joining the chip 5 and the chip supporting member 3, and it is possible to perform high-precision bonding.
[0043]
(Embodiment 2)
FIG. 10 is an enlarged schematic view of a bonding portion of the flip chip bonder according to the second embodiment.
[0044]
The bonding processing unit 28 of the flip chip bonder 1 has substantially the same configuration as the bonding processing unit 2 shown in FIG. 2 of the first embodiment, and the chip 5 picked up from the semiconductor wafer 4 is attached to the tip of the bonding head 2b. It is sucked and held by the provided collet 2c. However, by disposing a sheet 2f, for example, a laminate material, between the chip suction surface of the collet 2c and the chip 5, displacement of the chip 5 from the collet 2c is prevented.
[0045]
In the sheet 2f, as shown in FIG. 10, for example, holes 2g are provided in accordance with the positions of the chip suction holes provided in the collet 2c. The sheet 2f is supplied from a reel 29 attached to the bonding section 28. The reel 29 moves up and down and has a structure capable of supplying a sheet 2f between the chip 5 and the collet 2c during bonding. If the chip 5 is displaced or the chip 5 is broken due to a foreign substance, for example, a projection made of metal constituting the bump electrode of the chip 5 attached to the sheet 2f, the reel 29 is rotated to rotate the sheet 2f. Unused parts are supplied. The number of processes may be set in advance, and a new sheet 2f may be supplied when a predetermined number of processes is reached.
[0046]
As described above, according to the second embodiment, the sheet 2f is interposed between the chip 5 and the collet 3 so that the chip 5 and the collet 2c of the chip 5 when joining the chip supporting member 3 are joined. Shift can be prevented. Further, by installing the reel 29 around which the sheet 2f is wound on the bonding processing section 28, when foreign matter adheres to the sheet 2f, the reel 29 can be rotated to automatically supply an unused portion of the sheet 2f. A mechanism is not required, the throughput of the flip chip bonder is improved, and the mechanism of the flip chip bonder can be simplified.
[0047]
As described above, the invention made by the inventor has been specifically described based on the embodiment of the invention. However, the invention is not limited to the embodiment and can be variously modified without departing from the gist thereof. Needless to say, there is.
[0048]
For example, in the above embodiment, the case where the present invention is applied to the tape type CSP, the carrier type CSP, and the bare chip has been described. However, the present invention is not limited to this, and the chip is flip-chip mounted on the chip supporting member. The present invention can be applied to any semiconductor device to be joined.
[0049]
【The invention's effect】
The effects obtained by typical aspects of the invention disclosed in the present application will be briefly described as follows.
[0050]
The chip suction surface of the collet provided at the tip of the bonding head is coated with a coating material having a higher coefficient of friction than the metal constituting the collet, or by interposing a sheet between the chip and the collet, the semiconductor chip and The displacement of the chip from the collet at the time of joining with the chip supporting member can be prevented, and highly accurate bonding can be performed.
[0051]
In addition, when foreign matter adheres to the sheet, the unused portion of the sheet can be supplied by rotating the reel around which the sheet is wound, eliminating the need for a cleaning mechanism, improving the throughput of the flip chip bonder, and improving the flip chip bonder. The mechanism of the chip bonder can be simplified.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a flip chip bonder according to a first embodiment.
FIG. 2 is an enlarged schematic view of a bonding portion of the flip chip bonder according to the first embodiment.
FIG. 3 is a cross-sectional view of a main part of a tape-type CSP on which chip bonding has been performed using the flip chip bonder according to the first embodiment.
FIG. 4 is a cross-sectional view illustrating a dicing step of the semiconductor wafer according to the first embodiment;
FIG. 5 is a cross-sectional view showing a state in which the singulated semiconductor chip according to the first embodiment is vacuum-adsorbed by a flip head.
FIG. 6 is a cross-sectional view showing a state where the semiconductor chip according to the first embodiment is on standby above a mount stage.
FIG. 7 is a sectional view showing a die bonding step according to the first embodiment;
FIG. 8 is a cross-sectional view of a main part of a carrier-type CSP to which chip bonding has been performed using the flip chip bonder according to the first embodiment.
FIG. 9 is a cross-sectional view of a main part of a bare chip on which chip bonding has been performed using the flip chip bonder according to the first embodiment;
FIG. 10 is an enlarged schematic view of a bonding portion of the flip chip bonder according to the second embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Flip chip bonder 2 Bonding processing part 2a Mounting stage 2b Bonding head 2c Collet 2d Coating material 2e Optical probe 2f Sheet 2g Hole 3 Chip support member 3A Interposer 3B Interposer 3C Mounting substrate 3a Lead 3b Wiring 3c Opening 4 Semiconductor wafer 5 Semiconductor chip 5a Main surface 5b Pad 5c Back surface 6 XY table 7 Recognition unit 8 Wafer setting unit 8a Wafer support 8b Flip head 9 Wafer lifter 10 Transport unit 11 Loader 12 Unloader 13 CSP
14 Bump electrode 15 Elastomer 16 Sealing part 17 Dicing tape 18 Carrier jig 19 Diamond blade 21 Pad electrode 22 Pad electrode 23 Bump electrode 24 Underfill resin 25 Pad electrode 26 Bump electrode 27 Underfill resin 28 Bonding processing part 29 Reel

Claims (5)

(A) arranging a chip supporting member on a mount stage;
(B) adsorbing the semiconductor chip to the collet;
(C) pressing the semiconductor chip adsorbed on the collet to the chip supporting member,
A method for manufacturing a semiconductor device, wherein a surface of the collet on which the semiconductor chip is adsorbed is coated with a material having a higher friction coefficient than a material forming the collet. (A) arranging a chip supporting member on a mount stage;
(B) adsorbing the semiconductor chip to the collet;
(C) pressing the semiconductor chip adsorbed on the collet to the chip supporting member,
A method of manufacturing a semiconductor device, wherein a surface of the collet for adsorbing the semiconductor chip is coated with ceramic. (A) arranging a chip supporting member on a mount stage;
(B) adsorbing the semiconductor chip to the collet;
(C) pressing the semiconductor chip adsorbed on the collet to the chip supporting member,
A method for manufacturing a semiconductor device, wherein a sheet is interposed between the collet and the semiconductor chip. (A) arranging a chip supporting member on a mount stage;
(B) adsorbing the semiconductor chip to the collet;
(C) pressing the semiconductor chip adsorbed on the collet to the chip supporting member,
A method for manufacturing a semiconductor device, wherein a sheet made of a laminate material is interposed between the collet and the semiconductor chip. (A) arranging a chip supporting member on a mount stage;
(B) a step of disposing a sheet having both ends wound around a reel between the collet and the semiconductor chip;
(C) adsorbing the semiconductor chip to the collet via the sheet;
(D) pressing the semiconductor chip adsorbed on the collet to the chip supporting member,
A method of manufacturing a semiconductor device, wherein the sheet is moved by rotating the reel.

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