JP2008251582A - Method of manufacturing chip provided with adhesive layer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a chip provided with an adhesive layer, concretely the chip wherein the adhesive layer having nearly the same shape as the bonding face of the chip and uniform thickness is provided on the bonding face thereof, and to provide a manufacturing method by which the chip provided with the adhesive layer can be efficiently obtained with high reliability. <P>SOLUTION: The method of manufacturing the chip 1 provided with the adhesive layer includes a step [1] to prepare a chip sticking film wherein a plurality of the chips are stuck at some spacing on a film that is provided with a base material 4 and adhesive layers 3A and 3B that are stacked thereon and are subjected to photolithography; a step [2] to expose the adhesive layer; and a step [3] to develop the exposed adhesive layer and remove the adhesive layer other than a portion with stuck chips. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a method for manufacturing a chip having an adhesive layer. More specifically, the present invention relates to a method for manufacturing a chip having an adhesive layer, and a manufacturing method using a film having a base material and a photolithographic adhesive layer laminated on the base material.

  In the manufacturing process of a semiconductor device, after a dicing process for cutting and separating a semiconductor wafer into individual chips, a die bonding process for die-bonding the chip and the substrate through an adhesive layer is performed through an expanding process or the like. .

  By the way, in recent years, thinning of chips has progressed, and in the case of thin chips, there are cases where they are usually separated into pieces by a dicing before grinding (DBG) process. That is, a groove (kerf) having a predetermined depth is formed from the wafer surface on which the semiconductor circuit is formed, a surface protection sheet is attached to the circuit surface, the back surface of the wafer is ground, and the wafer thickness is reduced. At the same time, it is finally divided into individual chips (see Patent Document 1). Next, when the obtained thin chip is die-bonded to the substrate, an adhesive layer having the same size as the surface needs to be formed on the die bonding surface of the chip.

Here, when a paste-like adhesive is used, it is difficult to form an adhesive layer with a uniform amount and thickness, and there is a problem that the adhesive rolls up to the chip surface during die bonding.
Therefore, there is a method in which an adhesive layer is formed on the die bonding surface of a thin chip using a die attach film (also referred to as DAF in this specification) composed of an adhesive layer and a base material, and the chip is fixed to the substrate. It has been adopted. In this case, after finally dividing into individual chips in the DBG step, and then sticking the DAF adhesive layer consisting of the adhesive layer and the base material to the ground surface and peeling the surface protective sheet, The adhesive layer exposed between the chips (the adhesive layer in the kerf width portion) must be cut.

Examples of the method for cutting the adhesive layer in the kerf width portion include a method of cutting with a blade (see Patent Document 2), a method of cutting with a laser (see Patent Document 3), and the like. In addition, a DAF adhesive layer composed of a stretchable base material and a brittle adhesive layer is attached to the ground surface, and the film is expanded to separate the gap between the chips. A method of breaking the layer (see Patent Document 4) has also been attempted.
JP-A-5-335411 Japanese Patent Laid-Open No. 2001-156027 Japanese Patent Laid-Open No. 2005-116739 JP 2006-203133 A

  However, the position of the thin chip may be displaced when the wafer is divided into individual chips by grinding the back surface of the wafer or when the DAF adhesive layer is adhered. Therefore, cutting with a blade may damage a misaligned chip, leaving room for improvement in production efficiency. In addition, the laser cutting is performed while reading the kerf width, but an expensive device is required, and further, there is a problem that the pyrolyzate or gasified adhesive layer is reattached (debris) to the chip surface and side surfaces. . Further, the cutting of the film by expanding the adhesive layer in the kerf width portion protrudes from the bonding surface of the chip and remains attached to the chip, so there is room for improvement in the reliability of the obtained semiconductor device.

  Note that the above-described problems may occur not only in thin chips obtained by the DBG process. For example, after a dicing process, after checking whether each chip is a non-defective product, only a non-defective chip may be attached to the DAF. Here, the above-described problem can also occur when the chip with the adhesive layer is peeled off from the DAF base material and die-bonded.

  Accordingly, an object of the present invention is to provide a method for manufacturing a chip having an adhesive layer, that is, a chip in which an adhesive layer having the same shape and a uniform thickness is formed on the bonding surface of the chip. It is in. Another object of the present invention is to provide a manufacturing method in which a chip having the adhesive layer can be obtained efficiently and with high reliability.

As a result of intensive studies, the present inventors have found that the above problems can be solved by a film having a specific adhesive layer, and have completed the present invention.
That is, a method for manufacturing a chip having an adhesive layer according to the present invention is as follows.
[1] A step of preparing a chip-attached film in which a plurality of chips are attached with a gap on the adhesive layer of a film having a base material and a photolithographic adhesive layer laminated on the base material When,
[2] exposing the adhesive layer;
[3] The step of developing the exposed adhesive layer and removing the adhesive layer other than the portion to which the chip is attached is included.

  The photolithographic adhesive layer is an adhesive layer formed from a positive photoresist composition, and the step [2] is preferably a step of exposing the adhesive layer from the chip side. .

  The photolithographic adhesive layer is an adhesive layer formed from a negative photoresist composition, and the step [2] exposes the adhesive layer from the substrate side through a mask. It is preferable that it is a process to perform.

The method of manufacturing a semiconductor device according to the present invention includes a step of fixing the chip to the substrate through the adhesive layer after obtaining the chip having the adhesive layer.
The film according to the present invention has a base material and a photolithographic adhesive layer laminated on the base material.

  The chip adhesion film according to the present invention is characterized in that a plurality of chips are adhered with a gap on the adhesive layer of the film.

  According to the method for manufacturing a chip having an adhesive layer of the present invention, an adhesive layer having the same shape and a uniform thickness can be formed on the bonding surface of the chip. Moreover, the chip | tip which has the said adhesive bond layer is obtained efficiently and with high reliability.

Hereinafter, the present invention will be described in detail.
A method for producing a chip having an adhesive layer according to the present invention comprises: [1] a plurality of adhesive layers on a film having a substrate and a photolithographic adhesive layer laminated on the substrate; A step of preparing a chip-attached film having chips attached with a gap; [2] a step of exposing the adhesive layer; and [3] developing the exposed adhesive layer to attach the chip. And a step of removing the adhesive layer other than the portion.

  Specifically, the photolithographic adhesive layer is an adhesive layer formed from a positive photoresist composition, and the adhesive layer formed from a negative photoresist composition. Therefore, each will be described below with reference to the drawings.

<When using a positive photoresist composition>
[Step [1]]
In the step [1], a plurality of chips 1 are placed on the adhesive layer 3A of the film 5A having the base material 4 and the positive photolithographic adhesive layer 3A laminated on the base material. A chip adhering film 10A adhering to each other is prepared (see FIGS. 1 and 2A). 2A is a cross-sectional view taken along line AA in FIG. As shown in FIG. 1, a plurality of chips 1 are attached on the adhesive layer 3 </ b> A, and a solid line between the chips 1 in FIG. 1 indicates a gap 2 between the chips 1. Therefore, the adhesive layer 3 </ b> A is exposed in the gap 2.

  As described above, the film 5A used in the step [1] has the base material 4 and the photolithographic adhesive layer 3A, and the photolithographic adhesive layer 3A is laminated on the base material 4. ing.

  The substrate 4 is not particularly limited, but polyethylene, polypropylene, polybutylene, polybutadiene, polymethylpentene, polyvinyl chloride, ethylene vinyl acetate copolymer, ethylene (meth) acrylic acid copolymer, ethylene (meth) acrylic acid. Examples thereof include resin films such as ester copolymers, polyethylene terephthalate, polybutylene terephthalate, polyurethane, polystyrene, polycarbonate, and ionomer. Moreover, the resin film which processed the surface of the said resin film with release agents, such as a silicone type, a fluorine type, and a long chain alkyl type, is mentioned.

The thickness of the base material 4 is preferably 10 to 1000 μm, more preferably 20 to 800 μm.
The photolithographic adhesive layer 3A is an adhesive layer formed from a positive photoresist composition.

The photo-modification mechanism of the positive photoresist composition is not particularly limited, and can be selected from all generally known systems. Specifically, o-naphthoquinonediazide and novolak systems (usually sulfonate esters are used for o-naphthoquinonediazide), poly (p-formyloxystyrene) systems, o-nitrobenzylcholine ester and methyl Methacrylate and methacrylic acid copolymer systems, dihydropyridine systems, and N-substituted maleimide / styrene copolymer systems.

These systems may be composite systems, and a thermosetting resin is appropriately mixed with the system to form a composition. As the thermosetting resin, an epoxy resin is preferably used.
It also uses photodegradation (systems that increase solubility through photodegradation and photodepolymerization to lower the molecular weight) and chemical amplification (systems consisting of alkali-soluble resins, dissolution inhibitors, and photoacid generators). The composition can be obtained by appropriately mixing a thermosetting resin in the system.

Examples of the alkali-soluble resin include hydroxy aromatic compounds such as phenol, cresol, ethylphenol, t-butylphenol, xylenol, naphthol, 1,4-dihydroxybenzene, 1,3-dihydroxybenzene, and formaldehyde, acetaldehyde, benzaldehyde, furfural, etc. A so-called novolak resin obtained by polycondensation with aldehyde, polyhydroxystyrene and derivatives thereof are preferably used.

  Examples of the compound containing the 1,2-naphthoquinonediazide group include 1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester, and 1,2-naphthoquinonediazide-5-sulfone. Examples include acid esters.

If necessary, the above composition may contain an organic solvent, an inorganic filler, an organic filler, a pigment, a dye, and the like.
The film 5A is obtained, for example, by appropriately adjusting the viscosity of the positive photoresist composition, applying the composition onto the substrate 4, drying by heating, and volatilizing the organic solvent.

In the film 5A, the thickness of the adhesive layer 3A is preferably 1 to 100 μm, more preferably 5 to 50 μm.
Until the obtained film is used in the present invention, the protective film is preferably laminated and stored on the adhesive layer 3A. The protective film is not particularly limited as long as it has appropriate peelability, and the same resin film as that of the specific example of the substrate 4 is used. When it has a protective film, it is preferable to use a film having a smaller adhesive force with the adhesive layer 3 </ b> A than the substrate 4.

The chip adhesion film 10A is obtained, for example, by a dicing before grinding (DBG) process using the above-described film 5A.
In the DBG process, as described in JP-A-5-335411, a groove (kerf) having a predetermined depth is formed from the wafer surface on which the semiconductor circuit is formed, and a surface protection sheet is applied to the circuit surface. Then, the back surface of the wafer is ground to reduce the thickness of the wafer, and finally, the wafer is divided into individual chips.
After sticking the film 5A of the present invention to the ground surfaces of the divided chips, the chip-adhering film can be obtained by peeling off the surface protection sheet. In addition, when peeling a surface protection sheet, it is preferable to adsorb and fix the film side.

As the wafer dicing apparatus, for example, a half cut wafer dicing apparatus DFD6361 manufactured by Disco Corporation is used. As the back grinding device, for example, a back grinding device DPG8760 manufactured by Disco Corporation is used. As a surface protection sheet, protection of various conventional articles,
Examples include various protective sheets that have been used for processing semiconductor wafers. In particular, in the present invention, surface protective sheets described in JP-A Nos. 2000-68237 and 2001-127029 are preferably used.

  According to such a DBG process, a chip attaching film 10A in which a plurality of thin chips 1 are attached with a gap 2 therebetween is obtained. The thickness of the chip 1 is usually 30 to 200 μm. When the conventional DAF is attached to the ground surface of the divided chips, the adhesive layer exposed between the chips must be cut with a blade or a laser when die-bonding the chip with the adhesive layer to the substrate. .

  However, the position of the thin chip is likely to shift when singulated or DAF is attached, and cutting with the blade or laser has a problem from the viewpoint of production efficiency. Furthermore, cutting with the blade may damage the misaligned chip, and the adhesive layer obtained by cutting with the laser is reattached to the chip surface and side surfaces from the pyrolyzate or gasified adhesive layer. There was a problem of debris. On the other hand, according to the present invention, even when the position of the thin chip is shifted, after the exposure and development processes described below, the bonding surface of the chip is substantially the same shape and uniform thickness as the surface. An adhesive layer having a thickness can be formed. Moreover, the chip | tip which has the said adhesive bond layer can be formed efficiently and with high reliability.

  Further, in the present invention, the chip adhesion film 10A may be a chip adhesion film in which chips obtained through, for example, an inspection process after the conventional dicing process are integrated.

  Specifically, first, in the dicing process, a wafer is stuck on a dicing tape, and the wafer is cut and separated into chips by a blade or the like. Next, for example, after checking whether or not each chip is a non-defective product if necessary, a plurality of non-defective chips are adhered on the film 5A with a predetermined gap to obtain a chip-attached film 10A. It is done.

[Step [2]]
In step [2], the adhesive layer 3A is exposed (see FIG. 2B).
Prior to exposure, it is preferable to fix the chip attachment film 10 </ b> A to the ring frame 6.

  Further, the adhesive layer 3A is exposed from the chip 1 side. When the positive photoresist composition is used, the part of the adhesive layer 3 </ b> A exposed in the development process described later is removed. Therefore, since the chip itself also serves as a mask, it is not necessary to prepare a mask as in the case of using a negative photoresist composition.

Examples of the irradiation light source 7 used in the step [2] include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, and a metal halide lamp. Further, various laser beams such as electron beam, X-ray, EUV, KrF excimer, ArF excimer may be used. The exposure amount is appropriately selected depending on the light source used, the thickness of the adhesive layer 3A, and the like. For example, in the case of ultraviolet irradiation from a high-pressure mercury lamp, when the thickness of the adhesive layer 3A is 5 to 20 μm, it is about 50 to 1000 mJ / cm ² .

[Step [3]]
In step [3], the exposed adhesive layer 3A is developed, and the adhesive layer 3A other than the portion to which the chip 1 is attached is removed (see FIG. 2C).

  Development can be carried out with an aqueous alkali solution, such as an aqueous alkali solution such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n- Primary amines such as propylamine, secondary amines such as diethylamine and di-n-propylamine, tertiary amines such as triethylamine and methyldimethylamine, tetramethylammonium hydroxide, trimethylhydroxyethylammonium hydro And quaternary ammonium salts such as oxides. Moreover, you may add and use alcohol, surfactant, etc. to these.

Examples of the development method include shower development, spray development, immersion development, and paddle development.
Development conditions are usually 20-60 ° C. for 1-10 minutes.

In this way, the chip 20A having the adhesive layer is manufactured.
In the present invention, after the chip 20A having the adhesive layer is manufactured, the semiconductor device may be manufactured by proceeding to the step of fixing the chip 20A to the substrate. Further, the chip 20A may be stored and transported in a state where the chip 20A is supported by the base material 4 through an adhesive layer from which a desired portion is removed. In this way, only good chips can be transported to the next process or the user, thereby simplifying the process management. In this case, the base material 4 has a role as a die sort film for storing and transporting the chip A. In addition, you may store and convey in the state before removing an adhesive bond layer.

<When using a negative photoresist composition>
[Step [1]]
In the step [1], a plurality of chips 1 are placed on the adhesive layer 3B of the film 5B having the base material 4 and the negative photolithographic adhesive layer 3B laminated on the base material. A chip adhering film 10B adhering to each other is prepared (see FIG. 3A). 3A is a cross-sectional view taken along the line AA in FIG.

  As described above, the film 5B used in the step [1] includes the base material 4 and the photolithographic adhesive layer 3B, and the photolithographic adhesive layer 3B is laminated on the base material 4. ing.

  As the substrate 4, the same resin film as in the case of the film 5 </ b> A is used. However, since the adhesive layer 3 </ b> B is exposed from the substrate 4 side as described later, the light that does not absorb the irradiated light is used. A transparent film is preferably used.

The photolithographic adhesive layer 3B is an adhesive layer formed from a negative photoresist composition.
The negative photoresist composition includes, for example, a photosensitive resin capable of alkali development and a photopolymerization initiator.

  The alkali-developable photosensitive resin is a compound having a hydrophilic group such as a carboxyl group, a hydroxyl group or an amide group and a double bond group such as an acrylate group, a methacrylate group, a vinyl group or an aryl group. In particular, it is used without being limited to the molecular weight or structure, and can be appropriately selected in consideration of the physical properties, polarity, compatibility of the other compound and the overall alkali developability.

Examples of the photopolymerization initiator include acetophenones, benzophenones, and thioxanthones.
These systems may be composite systems, and a thermosetting resin is appropriately mixed with the system to form a composition. As the thermosetting resin, an epoxy resin is preferably used.

If necessary, the composition may contain a photosensitive polyfunctional monomer, an organic solvent, an inorganic filler, an organic filler, a pigment, a dye, and the like.
In the case of the film 5A, the manufacturing method of the film 5B, the point that the protective film is preferably laminated and stored on the adhesive layer 3B until used in the present invention, and the thickness of the adhesive layer 3B in the film 5B are also used. It is the same.

  The chip attachment film 10B may be a film obtained by a DBG process, similarly to the chip attachment film 10A. Moreover, this chip adhesion film 10B can be obtained by using the film 5B instead of the film 5A in the DBG process described above. Further, similarly to the chip attachment film 10A, the chip attachment film 10B may be a film in which chips obtained through, for example, an inspection process are integrated after the conventional dicing process.

[Step [2]]
In step [2], the adhesive layer 3B is exposed (see FIG. 3B).
Prior to exposure, it is preferable to fix the chip attachment film 10B to the ring frame 6 as in the case of the chip attachment film 10A.

  Further, the adhesive layer 3 </ b> B is exposed from the substrate 4 side through the mask 8. The mask 8 has a pattern such that the adhesive layer 3B exposed between the chips 1 is not exposed, and the mask 8 is disposed at a position where the adhesive layer 3B exposed between the chips 1 is not exposed. . Therefore, when a negative photoresist composition is used, the part of the adhesive layer 3B that has not been exposed in the development step described later is removed.

About the irradiation light source 7 used for process [2], and the exposure amount, the means similar to the case of the chip | tip adhesion film 10A and the exposure amount comparable are used.
[Step [3]]
In step [3], the exposed adhesive layer 3B is developed, and the adhesive layer 3B other than the portion to which the chip 1 is attached is removed (see FIG. 3C).

Development can be performed with an alkaline aqueous solution, and the alkaline aqueous solution, the development method, and the development conditions are the same as in the case of the chip-attached film 10A.
In this way, the chip 20B having the adhesive layer is manufactured.

  In the present invention, as in the case of the chip 20A, after the chip 20B having the adhesive layer is manufactured, the process may proceed to the step of fixing the chip 20B to the substrate to manufacture the semiconductor device. Further, the chip 20B may be stored and transported in a state where it is supported by the base material 4 via an adhesive layer from which a desired portion has been removed. In this case, the base material 4 has a role as a die sort film for storing and transporting the chips B. In addition, you may store and convey in the state before removing an adhesive bond layer.

<Method for Manufacturing Semiconductor Device>
As described above, the method for manufacturing a semiconductor device according to the present invention includes manufacturing a chip having an adhesive layer obtained by using a positive photoresist composition or a negative photoresist composition, and then further manufacturing the adhesive. A step of fixing the chip to the substrate via the layer (fixing step).

  Specifically, first, a chip 20A or 20B having an adhesive layer is picked up. If the expansion is performed as necessary, the gap between the chips is widened, and the chip recognition of the pickup device is improved.

  The chip 20A or 20B having the picked-up adhesive layer is die-bonded on a predetermined substrate, and the chip and the substrate are firmly fixed by heat-curing the adhesive layer. Although it depends on the adhesive layer, the heating temperature is usually 100 to 200 ° C., and the heating time is usually 10 to 200 minutes. In addition, this heat curing condition may be step curing, and examples of the heat curing device include a normal heating oven, a heating and pressing oven, a hot plate, and an electromagnetic induction heating device. The apparatus / method is not limited.

  Usually, following the above-described fixing step, an assembling step for assembling a substrate on which the adhesive layer has been heat-cured into a semiconductor device is performed. For example, a wire bonding process for connecting wires, a molding process using a sealing resin, and the like are performed. In this way, a semiconductor device is manufactured. According to the present invention, since a chip having an adhesive layer that is substantially the same shape as the bonding surface and has a uniform thickness is used, a semiconductor device having high efficiency and high reliability can be obtained.

FIG. 1 is a diagram for explaining a method for producing a chip having an adhesive layer of the present invention. FIG. 2 is a diagram for explaining a method of manufacturing a chip having an adhesive layer according to the present invention. FIG. 3 is a diagram for explaining a method for manufacturing a chip having an adhesive layer according to the present invention.

Explanation of symbols

1: Chip 2: Gap 3A: Photolithographic adhesive layer 3B: Photolithographic adhesive layer 4: Substrate 5A: Film 5B: Film 6: Ring frame 7: Irradiation light source 8: Mask 10A: Chip adhesion film 10B: chip adhesion film 20A: chip with adhesive layer 20B: chip with adhesive layer

Claims (6)

[1] A step of preparing a chip-attached film in which a plurality of chips are attached with a gap on the adhesive layer of a film having a base material and a photolithographic adhesive layer laminated on the base material When,
[2] exposing the adhesive layer;
[3] A method for producing a chip having an adhesive layer, comprising: developing the exposed adhesive layer and removing the adhesive layer other than the part to which the chip is attached. The photolithographic adhesive layer is an adhesive layer formed from a positive photoresist composition;
The method of manufacturing a chip having an adhesive layer according to claim 1, wherein the step [2] is a step of exposing the adhesive layer from the chip side. The photolithographic adhesive layer is an adhesive layer formed from a negative photoresist composition;
The method of manufacturing a chip having an adhesive layer according to claim 1, wherein the step [2] is a step of exposing the adhesive layer from the substrate side through a mask.   A method for manufacturing a semiconductor device, comprising: obtaining a chip having the adhesive layer according to claim 1, and further fixing the chip to a substrate through the adhesive layer.   A film comprising a base material and a photolithographic adhesive layer laminated on the base material.   A chip adhering film comprising a plurality of chips adhering to the adhesive layer of the film according to claim 5 with a gap therebetween.

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