JP5583080B2 - Wafer processing tape and semiconductor processing method using the same - Google Patents

Description

  The present invention relates to a wafer processing tape used in a manufacturing process of a semiconductor device and a semiconductor processing method using the same, and in particular, a dicing process of dividing a semiconductor wafer and an adhesive layer by a thin grindstone that rotates at a high speed, and cutting. The present invention relates to a dicing die bonding tape used in a die bonding step of picking up an individual semiconductor wafer together with an adhesive layer separated into pieces and laminating it on a substrate, and a semiconductor processing method using the same.

  As a wafer processing tape used in a semiconductor device manufacturing process, a dicing die bonding tape in which a dicing tape (adhesive tape) and a thermosetting adhesive film containing an epoxy resin component are laminated has been proposed ( For example, Patent Documents 1 to 3). These dicing die-bonding tapes can firmly bond a semiconductor chip and a substrate by thermosetting by including a compound having an epoxy group in an adhesive layer (adhesive film). In addition, by making the pressure-sensitive adhesive layer of the dicing tape energy-ray curable, the adhesive strength of the dicing tape can be reduced by UV irradiation, etc., and the interface between the pressure-sensitive adhesive layer and the adhesive layer can be easily peeled off. It is possible to pick up a semiconductor wafer separated into semiconductor chips by dividing from a dicing tape together with an adhesive layer separated into pieces by dividing.

The dicing die bonding tape as described above is capable of reliably cutting and dividing the semiconductor wafer and the adhesive layer, picking up one by one, and providing the die bonding process with a high yield, and the semiconductor chip and There is also a demand for the ability to firmly bond the substrate.
However, when the adhesive layer is cut together with a semiconductor wafer with a thin grindstone that rotates at high speed, the above-mentioned dicing die-bonding tape is used when a part of the adhesive layer that should have been separated is re-adhered and picked up. In addition, a so-called “double die error” occurs in which a part of the semiconductor chip is connected to the adjacent semiconductor chip and is used in the die bonding process, resulting in a deterioration in process yield.

  In order to suppress the occurrence of “double die error”, it is at least necessary to try to destroy the re-adhesion by expanding the dicing tape to increase the distance between the semiconductor chips to some extent. Accordingly, the support base material of the dicing tape is required to have uniform extensibility, and as such a dicing tape, the support base material is an ethylene- (meth) acrylic acid binary copolymer or ethylene- (meth) acrylic acid- ( A tape made of a meth) acrylic acid alkyl ester terpolymer or an ionomer resin obtained by chelating and crosslinking them with metal ions has been proposed (for example, Patent Documents 4 to 8).

JP 2002-226996 A JP 2005-303275 A JP 2006-299226 A JP-A-5-156219 Japanese Patent Laid-Open No. 5-21234 JP 2000-345129 A Japanese Patent Laid-Open No. 2003-158098 JP 2007-88240 A

  However, even with such a dicing tape, the effect of suppressing the occurrence of a double die error is not always sufficient, and there is a problem that a double die error occurs occasionally. Therefore, in order to further suppress the occurrence of a double die error, it is required to sufficiently suppress the re-adhesion between semiconductor chips during pickup.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a wafer processing tape capable of sufficiently suppressing re-adhesion between semiconductor chips during pickup and a semiconductor processing method using the same. To do.

The invention described in claim 1
When a thermosetting adhesive layer containing a compound having an epoxy group is laminated on the pressure-sensitive adhesive layer of a pressure-sensitive adhesive tape composed of a support substrate and a pressure-sensitive adhesive layer, and the bonded semiconductor wafer is separated into pieces In the wafer processing tape in which the semiconductor wafer, the adhesive layer and the pressure-sensitive adhesive layer are cut, and the support base material is cut to a predetermined depth in the thickness direction ,
The supporting substrate is made of an ionomer resin obtained by crosslinking an ethylene- (meth) acrylic acid binary copolymer or an ethylene- (meth) acrylic acid- (meth) acrylic acid alkyl ester ternary copolymer with a metal ion. ,
The weight fraction of the (meth) acrylic acid component in the copolymer is 1% or more and less than 10%, and the degree of neutralization of the (meth) acrylic acid in the ionomer resin is 50% or more. It is characterized by being.

The invention according to claim 2 is the wafer processing tape according to claim 1,
The pressure-sensitive adhesive layer has a structure of one layer or two or more layers, and at least one of them is formed of an energy ray curable pressure-sensitive adhesive.

The invention according to claim 3 is a semiconductor processing method using the wafer processing tape according to claim 1 or 2,
Bonding the semiconductor wafer to the wafer processing tape;
Next, the semiconductor wafer and the adhesive layer and the pressure-sensitive adhesive layer of the wafer processing tape are cut using a thin grindstone that rotates at high speed, and the supporting base material of the wafer processing tape is 10 μm in the thickness direction. Cutting the semiconductor wafer and the adhesive layer into pieces,
Next, in a state where the adhesive tape of the wafer processing tape is expanded, the step of picking up the semiconductor wafers that are separated into pieces,
It is characterized by having.

The invention according to claim 4 is the semiconductor processing method according to claim 3,
The support substrate has a thickness of 60 μm or more,
In the step of dividing into pieces, the support base material is cut by 10 to 30 μm in the thickness direction.

Below, the background that led to the completion of the present invention will be described.
In the dicing process using a thin grindstone that rotates at a high speed, the present inventors have developed a so-called “double die error” in which an adhesive layer that should have been separated is partially reattached. It has been found that the aggregate of cutting waste including the waste of the agent layer is clogged between adjacent semiconductor chips as shown in FIG. 6, thereby causing re-adhesion between adjacent semiconductor chips. .

  Re-adhesion between adjacent semiconductor chips by cutting waste containing such an adhesive component can be destroyed by expanding the dicing tape (adhesive tape) in the pickup process to widen the distance between the semiconductor chips. In some cases. In order to widen the distance between all semiconductor chips, the support base material of the dicing tape is required to be uniformly expandable. As a material of such a support base material, an ethylene- (meth) acrylic acid binary copolymer is used. Alternatively, an ethylene- (meth) acrylic acid- (meth) acrylic acid alkyl ester ternary copolymer, or an ionomer resin obtained by crosslinking either of them with a metal ion can be used.

However, when the re-adhesion is strong, in order to destroy all the re-adhesion, the uniform extensibility of the supporting base material is not sufficient, and the re-adhesion part must be embrittled.
If the compound having epoxy group is removed from the adhesive layer of the dicing die bonding tape, the adhesive component in the cutting waste generated in the dicing process as the adhesive performance of the adhesive layer due to thermal curing decreases. Adhesive strength derived from is also reduced. As a result, the re-adhesion part between adjacent semiconductor chips also becomes brittle, and the occurrence of double die error can be suppressed. In such a case, the adhesive force of the adhesive layer to the semiconductor chip is reduced and the original performance is reduced. Will be damaged.
Therefore, as a measure for suppressing the occurrence of double die error, a method that embrittles re-adhesion between semiconductor chips by cutting waste containing an adhesive component without reducing the compound having an epoxy group contained in the adhesive layer Is required.

  As a result of intensive studies, the present inventors have found that an ethylene- (meth) acrylic acid binary copolymer or an ethylene- (meth) acrylic acid- (meth) acrylic acid alkyl ester used as a support substrate for a dicing die bonding tape. It has been found that the occurrence of double die error can be suppressed by making the proportion of the (meth) acrylic acid component in the ternary copolymer smaller than a predetermined amount and ionizing with metal ions. By suppressing the (meth) acrylic acid component of the ionomer resin used for the support substrate and forming a stable complex with the metal ion to reduce the reaction activity, the carboxyl group of the (meth) acrylic acid component and the adhesive layer Since the reaction with the compound having an epoxy group in the inside can be suppressed, the adhesive force between the substrate waste component and the adhesive waste component in the cutting waste generated in the dicing process is reduced, and the cutting waste is reduced. The adhesion part between semiconductor chips can be embrittled.

It is (meth) acrylic in a copolymer (binary copolymer, ternary copolymer) that has the effect of suppressing the occurrence of double die error while imparting sufficient uniform extensibility to the support substrate. An ionomer resin in which the weight fraction of the acid component is less than 10% and the degree of neutralization of (meth) acrylic acid in the ionomer resin is 50% or more, more preferably, the weight fraction of the (meth) acrylic acid component is It is an ionomer resin having a neutralization degree of 3% to 5% and a (meth) acryl neutralization degree of 50% or more.
If the weight fraction of the (meth) acrylic acid component in the copolymer in the support substrate (ionomer resin) is 1% or more, uniform supportability can be expected from the support substrate, and if it is 3% or more, further Uniform expandability of the support substrate can be expected.

The weight fraction of the (meth) acrylic acid component in the copolymer in the ionomer resin can be quantified by combining NMR and methods such as pyrolysis GC-ms spectrum measurement.
For example, the alkyl group in the alkyl ester domain of the ethylene- (meth) acrylic acid- (meth) acrylic acid alkyl ester terpolymer can be identified from the peak of the pyrolysis GC-ms spectrum.
In addition, if ¹ H-NMR is used, the hydrogen peak of the α-position hydrogen of the (meth) acrylic acid unit or the methyl group of the (meth) acrylic acid unit in the ionomer resin of the ethylene- (meth) acrylic acid binary copolymer. Can be quantified by comparing the integrated value of with the integrated value of the peak of hydrogen in ethylene units. When the peak derived from the methyl group of the (meth) acrylic acid unit and the peak derived from the ethylene end having a chemical shift or the ester end of the (meth) acrylic acid alkyl ester are observed partially overlapping each other, Since the peak derived from the methyl group of the (meth) acrylic acid unit appears on the lower magnetic field side, the fraction of the (meth) acrylic acid component can be estimated by the lower magnetic field side integration. Also for ethylene- (meth) acrylic acid- (meth) acrylic acid alkyl ester terpolymers, α-position hydrogen of (meth) acrylic acid and (meth) acrylic acid alkyl ester is obtained using ¹ H-NMR. Alternatively, from the peak of the hydrogen of the methyl group of the (meth) acrylic acid unit, the total of the (meth) acrylic acid fraction and the (meth) acrylic acid alkyl ester fraction can be quantified, and the (meth) acrylic acid alkyl ester unit Since the fraction of only the (meth) acrylic acid alkyl ester can be quantified from the hydrogen peak bonded to the 1st carbon of the alkyl group, the weight fraction of (meth) acrylic acid can be calculated.

Furthermore, by setting the degree of neutralization of (meth) acrylic acid by metal ions to 50% or more, the (meth) acrylic acid component of the ionomer resin is suppressed, and a stable complex is formed with the metal ions to reduce the reaction activity. Since the reaction between the carboxyl group of the (meth) acrylic acid component and the compound having the epoxy group in the adhesive layer can be suppressed, the base material scrap component and the adhesive in the cutting waste generated in the dicing process The adhesion force between the chip components can be reduced, and the adhesion portion between the semiconductor chips due to the cutting chips can be embrittled. As a result, the occurrence of a double die error can be accurately suppressed. The degree of neutralization of the (meth) acrylic acid can be quantified by various spectroscopic analyzes such as ICP emission analysis. For example, it is possible to simultaneously identify a metal ion species in an ionomer and quantify its weight fraction by ICP emission analysis. Furthermore, if the weight fraction of (meth) acrylic acid in the ionomer is known by a method combining NMR and pyrolysis GC-ms spectrum measurement, the degree of neutralization can be quantified together with the information on the metal ions.
By applying such support base material to wafer processing tapes such as dicing die bonding tape, the occurrence of double die errors can be suppressed, and in addition, the amount of cut into the support base material in the dicing process can be reduced. The deeper the effect, the greater the effect. On the other hand, if the amount of cut into the support base is increased more than necessary, there is a risk of breakage during tape expansion.
If the depth of cut into the supporting substrate is 10 μm or more in the thickness direction, there is a sufficient effect in suppressing the occurrence of double die error, and the supporting substrate is cut to 30 μm or less in the thickness direction. If the thickness of the material is 60 μm or more, the supporting substrate can be prevented from being broken.

  Further, the pressure-sensitive adhesive layer of the above-mentioned dicing die bonding tape has a structure of one layer or two or more layers, and at least one of them is formed of an energy ray-curable pressure-sensitive adhesive, so that the semiconductor wafer is strengthened in the dicing process. The adhesive force of the dicing tape can be effectively reduced by irradiating energy rays after dicing, and an excessive load is applied to the semiconductor chip during the pick-up process. Therefore, the semiconductor chip and the separated adhesive layer can be easily peeled from the surface of the pressure-sensitive adhesive layer of the dicing tape.

  According to the wafer processing tape of the present invention, the weight fraction of the (meth) acrylic acid component in the copolymer is 1% or more and less than 10%, and the neutralization of (meth) acrylic acid in the ionomer resin. Since the degree is 50% or more, the re-adhesion between the semiconductor chips at the time of pickup can be sufficiently suppressed, and the occurrence of a double die error can be further suppressed.

  Further, according to the semiconductor processing method of the present invention, the wafer processing tape supporting substrate is arranged in the thickness direction in the step of using the wafer processing tape of the present invention and separating the semiconductor wafer and the adhesive layer into pieces. Since the cutting is performed by 10 μm or more, the re-adhesion between the semiconductor chips at the time of pickup can be further sufficiently suppressed, and the occurrence of double die error can be further suppressed.

It is sectional drawing which shows schematic structure of the dicing die-bonding tape which concerns on embodiment of this invention. It is a figure for demonstrating the rough usage method of a dicing die-bonding tape, Comprising: It is the figure which bonded the semiconductor wafer on the dicing die-bonding tape. It is a figure for demonstrating the process (dicing process) subsequent to FIG. It is a figure for demonstrating the subsequent process (expanding process) of FIG. It is a figure for demonstrating the process (pickup process) subsequent to FIG. It is the electron micrograph which copied a mode that the cutting waste generated at the time of dicing was clogged between semiconductor chips.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the present embodiment, a dicing die bonding tape will be described as an example of the wafer processing tape.

FIG. 1 is a cross-sectional view showing a dicing die bonding tape 10 of this embodiment.
As shown in FIG. 1, the dicing die bonding tape 10 has an adhesive layer 13 laminated on a dicing tape 12 as an adhesive tape comprising a support base 12a and an adhesive layer 12b formed thereon. Configured. FIG. 1 shows a state in which a release liner 11 is provided on a dicing die bonding tape 10 in order to protect the adhesive layer 13.

In addition, the adhesive layer 12b may be comprised by the adhesive layer of one layer, and may be comprised by what laminated | stacked the adhesive layer of two or more layers.
In addition, the dicing tape 12 and the adhesive layer 13 may be cut (precut) into a predetermined shape in advance according to the use process and the apparatus.
The dicing die bonding tape 10 may be in a form cut for each semiconductor wafer, or in a form in which a plurality of long sheets formed in a roll shape are wound. There may be.

(How to use dicing die bonding tape)
In the manufacturing process of the semiconductor device, the dicing die bonding tape 10 is used as follows.
FIG. 2 shows a state where the semiconductor wafer 1 and the ring frame 20 are bonded to the dicing die bonding tape 10.

  First, as shown in FIG. 2, the dicing tape 12 is attached to the ring frame 20, and the semiconductor wafer 1 is attached to the adhesive layer 13. There is no restriction on the order of these attachments, and the dicing tape 12 may be attached to the ring frame 20 after the semiconductor wafer 1 is attached to the adhesive layer 13, or the dicing tape 12 may be attached to the ring frame 20. The bonding of the semiconductor wafer 1 to the adhesive layer 13 may be performed simultaneously.

And the dicing process of the semiconductor wafer 1 is implemented using the thin grindstone 21 which rotates at high speed (FIG. 3). At that time, the adhesive layer 13 and the pressure-sensitive adhesive layer 12b are cut and cut together with the semiconductor wafer 1, and the support base 12a is cut by 10 μm to 30 μm in the thickness direction.
In addition, you may cut to the predetermined depth from the semiconductor wafer 1 surface by one time of cutting, and you may cut to the predetermined depth by multiple times of cutting.
Specifically, in order to dice the semiconductor wafer 1 and the adhesive layer 13 with the thin grindstone 21, the dicing die bonding tape 10 is sucked and supported from the dicing tape 12 side by the suction stage 22.
Then, the semiconductor wafer 1 and the adhesive layer 13 are cut into semiconductor chips and separated into pieces by the thin grindstone 21 that rotates at high speed.

When the pressure-sensitive adhesive layer 12b of the dicing tape 12 has a structure of one layer or two or more layers, and at least one of the layers is formed of an energy ray curable pressure-sensitive adhesive, the lower surface side of the dicing tape 12 ( It is desirable to cure the pressure-sensitive adhesive layer 12b and reduce its adhesive strength by irradiating energy rays from the support base 12a side.
Further, when the pressure-sensitive adhesive layer 12b is formed by laminating two or more pressure-sensitive adhesive layers, one or all of the pressure-sensitive adhesive layers are formed with an energy ray-curable pressure-sensitive adhesive, and irradiated with energy rays. You may make it harden | cure and reduce the adhesive force of this one layer or all the layers of each adhesive layer.
Note that the adhesive force of the dicing tape 12 may be reduced by external stimulation such as heating, instead of irradiation with energy rays.

Thereafter, as shown in FIG. 4, an expanding process is performed in which the dicing tape 12 holding the diced semiconductor wafer 1 (that is, the semiconductor chip 2) and the diced adhesive layer 13 is stretched in the radial direction of the ring frame 20. .
Specifically, the hollow cylindrical push-up member 30 is raised from the lower surface side of the dicing tape 12 with respect to the dicing tape 12 holding the plurality of semiconductor chips 2 and the adhesive layer 13, and the dicing tape 12 is The ring frame 20 is stretched in the radial direction. This expands the distance between the semiconductor chips 2 by the expanding process, destroys the re-adhesion (re-adhesion) between the semiconductor chips 2 due to the cutting waste generated in the dicing process, and prevents the occurrence of double die errors in the pick-up process. can do.

After performing the expanding process, as shown in FIG. 5, the pick-up process for picking up the semiconductor chip 2 is performed with the dicing tape 12 in the expanded state.
Specifically, the semiconductor chip 2 is pushed up by the pin 31 from the lower surface side of the dicing tape 12 and the semiconductor chip 2 is adsorbed from the upper surface side of the dicing tape 12 by the adsorption jig 32, thereby attaching the semiconductor chip 2 to the adhesive layer 13. Pick up with.

Then, after performing the pickup process, the die bonding process is performed.
Specifically, the semiconductor chip 2 is adhered and laminated to a lead frame, a package substrate, or the like by an adhesive layer 13 (adhesive film) picked up together with the semiconductor chip 2 in the pickup process.

  Hereinafter, each component of the dicing die bonding tape 10 of this embodiment will be described in detail.

(Adhesive layer)
The adhesive layer 13 is peeled off from the dicing tape 12 and attached to the semiconductor chip 2 when the semiconductor chip 2 is picked up after the semiconductor wafer 1 or the like is bonded and diced, and the semiconductor chip 2 is attached to the substrate or lead frame. It is used as an adhesive when it is fixed to the like. Therefore, the adhesive layer 13 has sufficient adhesion reliability for bonding and fixing the semiconductor chip 2 to a substrate, a lead frame, or the like in the die bonding step.

The adhesive layer 13 is obtained by forming a film of an adhesive in advance, includes at least one compound having an epoxy group, and other known polyimide resins, polyamide resins, polyether resins, polyester resins, polyesters as necessary. Polymer components such as imide resins, phenoxy resins, polysulfone resins, polyphenylene sulfide resins, polyether ketone resins, chlorinated polypropylene resins, acrylic resins, polyurethane resins, epoxy resins, polyacrylamide resins, melamine resins, and mixtures thereof, and inorganic fillers Or a hardening accelerator may be included. Further, a silane coupling agent or a titanium coupling agent may be added as an additive in order to increase the adhesive force to the substrate, the lead frame or the like.
The compound having an epoxy group is not particularly limited as long as it is cured and exhibits an adhesive action, but an epoxy resin having a bifunctional group or more and less than 500 to 5000 is preferable. Examples of such epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, alicyclic epoxy resins, aliphatic chain epoxy resins, phenol novolac type epoxy resins, and cresol novolac types. Epoxy resin, bisphenol A novolak type epoxy resin, diglycidyl etherified product of biphenol, diglycidyl etherified product of naphthalenediol, diglycidyl etherified product of phenol, diglycidyl etherified product of alcohol, and alkyl substitution products thereof , Bifunctional epoxy resins such as halides and hydrogenated products, and novolac type epoxy resins. Moreover, what is generally known, such as a polyfunctional epoxy resin and a heterocyclic ring-containing epoxy resin, can also be applied.
These can be used alone or in combination of two or more.
Furthermore, components other than the epoxy resin may be included as impurities within a range that does not impair the characteristics.

The thickness of the adhesive layer 13 is not particularly limited, but is usually preferably about 5 to 100 μm.
The adhesive layer 13 may be laminated on the entire surface of the dicing tape 12, but an adhesive film that has been cut (pre-cut) into a shape corresponding to the semiconductor wafer 1 to be bonded in advance is laminated to form the adhesive layer. 13 may be formed. When the adhesive film corresponding to the semiconductor wafer 1 is laminated, as shown in FIG. 2, the adhesive layer 13 is provided in the portion where the semiconductor wafer 1 is bonded, and the portion where the dicing ring frame 20 is bonded. Only the dicing tape 12 is present without the adhesive layer 13. In general, since the adhesive layer 13 is difficult to peel off from the adherend, the ring frame 20 can be bonded to the dicing tape 12 by using a pre-cut adhesive film, and the ring frame 20 can be peeled off when the tape is peeled off after use. The effect that it is hard to produce the adhesive residue on is obtained.

(Dicing tape)
The dicing tape 12 has a sufficient adhesive force so that the semiconductor wafer 1 does not peel when dicing the semiconductor wafer 1, and the adhesive layer 13 is easily picked up when picking up the semiconductor chip 2 after dicing. As shown in FIG. 1, an adhesive layer 12b is provided on a support base 12a.

The support base 12a is made of an ionomer resin obtained by crosslinking an ethylene- (meth) acrylic acid binary copolymer or an ethylene- (meth) acrylic acid- (meth) acrylic acid alkyl terpolymer with a metal ion. .
The weight fraction of the (meth) acrylic acid component in the copolymer is 1% or more and less than 10%, and the degree of neutralization of acrylic acid in the ionomer resin is 50% or more.

Here, the weight fraction of the (meth) acrylic acid component in the copolymer is expressed by the following structural formula 1 when the support substrate 12a is made of an ionomer resin obtained by crosslinking an ethylene-acrylic acid binary copolymer with a metal ion. It is specified by “m · Mw _m / (n · Mw _n + m · Mw _m )”.
When the support substrate 12a is made of an ionomer resin obtained by crosslinking an ethylene-methacrylic acid binary copolymer with metal ions, “b · Mw _b / (a · Mw _a + b · Mw _b ) in the following structural formula 2 ”.
When the support substrate 12a is made of an ionomer resin obtained by crosslinking an ethylene-acrylic acid-acrylic acid alkyl ester terpolymer with a metal ion, “m · Mw _m / (n · Mw _{n) in the following} structural formula 3 + M · Mw _m + l · Mw _l ) ”.
The supporting substrate 12a is ethylene - methacrylic acid - If the alkyl methacrylate terpolymer consisting ionomer resins crosslinked with metal ions, the following structural formula _{4 "b · Mw b / (} a · Mw a + B · Mw _b + c · Mw _c ) ”.

  Further, the degree of neutralization of (meth) acrylic acid in the ionomer resin is defined as the degree to which the (meth) acrylic acid portion of the ionomer resin is ionized (neutralized) by metal ions (for example, Vol. 32, No. 2, 65-69, 2004). In addition, m is m in the following structural formula 1 or the following structural formula 3 (that is, the number of repeating units of acrylic acid), and b is b in the following structural formula 2 or the following structural formula 4 (that is, repeating of methacrylic acid). Unit number).

The kind of metal ion of the ionomer resin is not particularly limited, but Zn ion is preferable from the viewpoint of contamination.
In addition, you may add antioxidant, an antiblocking agent, a leveling agent, etc. to an ionomer resin as needed.

The thickness of the support base 12a is not particularly specified, but even when the support base 12a is cut during dicing, the support base 12a may have a thickness of 60 μm or more in terms of providing strength that does not break when the dicing tape 12 is expanded. preferable.
In consideration of the case where the semiconductor chip 2 is pushed up from the lower surface side of the dicing tape 12 by the pin 31 and picking up the adhesive layer 13 and the pressure-sensitive adhesive layer 12b is promoted at the time of pickup, the thickness of the support base 12a is 150 μm or less. It is preferable from the viewpoint of substrate rigidity.
In addition, in order to prevent peeling of the pressure-sensitive adhesive layer 12b and the support base material 12a, corona discharge, plasma irradiation, ultraviolet irradiation, and other activities are performed on the surface of the support base material 12a before the pressure-sensitive adhesive layer 12b is laminated. The treatment may be performed.
In addition, the lower surface of the support substrate 12a (the surface opposite to the surface on which the pressure-sensitive adhesive layer 12b is formed) is coated on the surface to prevent blocking when the dicing die bonding tape 10 is wound in a roll shape. A fine coating may be provided, or a known coating method that imparts slipperiness may be applied.

The pressure-sensitive adhesive layer 12b is not particularly defined as long as it firmly holds the semiconductor wafer 1 during dicing and can be easily peeled off from the adhesive layer 13 during pick-up, but it has a single-layer or two-layer structure. It is preferable that at least one of them is formed of an energy ray curable pressure-sensitive adhesive.
In addition, the thickness of the pressure-sensitive adhesive layer 12b is not particularly limited and may be appropriately set, but is preferably 5 to 30 μm.

  As the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 12b, known chlorinated polypropylene resins, acrylic resins, polyester resins, polyurethane resins, epoxy resins, addition-reactive organopolysiloxane resins, silicon acrylate resins, used for pressure-sensitive adhesives, Such as ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-acrylic acid copolymer, polyisoprene, styrene-butadiene copolymer and hydrogenated products thereof. It is preferable to prepare by appropriately blending a radiation-polymerizable compound into various elastomers and mixtures thereof. Various surfactants and surface smoothing agents may be added.

Examples of the radiation-polymerizable compound include a low molecular weight compound having at least two photopolymerizable carbon-carbon double bonds in a molecule that can be three-dimensionally reticulated by light irradiation, and a photopolymerizable carbon-carbon double bond group. A polymer or oligomer having a substituent as a substituent is used.
Specifically, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butylene glycol diacrylate, 1,6 hexanediol diacrylate For example, acrylate, polyethylene glycol diacrylate, oligoester acrylate, silicon acrylate, etc., acrylic acid, copolymers of various acrylic esters, and the like are applicable.
In addition to the acrylate compounds as described above, urethane acrylate oligomers can also be used. The urethane acrylate oligomer includes a polyol compound such as a polyester type or a polyether type, and a polyvalent isocyanate compound (for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diene). A terminal isocyanate urethane prepolymer obtained by reacting isocyanate, 1,4-xylylene diisocyanate, diphenylmethane 4,4-diisocyanate, etc.) with an acrylate or methacrylate having a hydroxyl group (for example, 2-hydroxyethyl) Acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, polyethylene glycol acrylate, polyethylene glycol methacrylate, etc.) Obtained by the reaction.

The pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 12b may be a mixture of two or more selected from the above resins.
The material of the above-mentioned pressure-sensitive adhesive mentioned as the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 12b contains as many nonpolar groups as possible in the molecular structure such as a trifluoromethyl group, a dimethylsilyl group, and a long-chain alkyl group. It is desirable for facilitating peeling from the adhesive layer 13 containing a highly polar epoxy group.
The pressure-sensitive adhesive (resin) that forms the pressure-sensitive adhesive layer 12b includes a radiation polymerizable compound that cures the pressure-sensitive adhesive layer 12b by irradiating the pressure-sensitive adhesive layer 12b, an acrylic pressure-sensitive adhesive, and photopolymerization initiation. It can also be prepared by appropriately blending an agent, a curing agent and the like.
When using a photopolymerization initiator, for example, isopropyl benzoin ether, isobutyl benzoin ether, benzophenone, Michler's ketone, chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, benzyldimethyl ketal, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethylphenyl Propane or the like can be used.

According to the wafer processing tape (dicing die bonding tape 10) described above, the pressure-sensitive adhesive layer 12b of the dicing tape 12 as a pressure-sensitive adhesive tape comprising the support base 12a and the pressure-sensitive adhesive layer 12b has an epoxy group. A thermosetting adhesive layer 13 containing a compound is laminated, and the support base 12a is made of an ethylene- (meth) acrylic acid binary copolymer or ethylene- (meth) acrylic acid- (meth). The acrylic acid alkyl ester terpolymer is made of an ionomer resin crosslinked with metal ions, and the weight fraction of the (meth) acrylic acid component in the copolymer (binary copolymer, ternary copolymer) is 1% or more and less than 10%, and the degree of neutralization of (meth) acrylic acid in the ionomer resin is 50% or more.
Therefore, the support base 12a has uniform expandability, and the re-adhesion part between the semiconductor chips 2 can be embrittled, so that the re-adhesion between the semiconductor chips 2 during pickup can be sufficiently suppressed, and double die error It is possible to further suppress the occurrence of

  Further, according to the dicing die bonding tape 10 described above, since the adhesive layer 13 includes a compound having an epoxy group, the semiconductor chip 3 can be firmly bonded onto the substrate by the adhesive layer 13.

  Further, according to the dicing die bonding tape 10 described above, the pressure-sensitive adhesive layer 12b has a structure of one layer or two or more layers, and at least one of them is formed of an energy ray curable pressure-sensitive adhesive. The semiconductor chip 2 and the separated adhesive layer 13 can be easily peeled from the surface of the pressure-sensitive adhesive layer 12b of the dicing tape 12.

In addition, according to the semiconductor processing method using the dicing die bonding tape 10 described above, the semiconductor wafer 1 is bonded to the dicing die bonding tape 10 and then the thin grindstone 21 that rotates at high speed is used for the semiconductor. The wafer 1 and the adhesive layer 13 and the adhesive layer 12b of the dicing die bonding tape 10 are cut, and the support base 12a of the dicing die bonding tape 10 is cut by 10 μm or more in the thickness direction, so that the semiconductor wafer 1 and The step of dicing the adhesive layer 13 (dicing step), and then the dicing tape 12 of the dicing die bonding tape 10 is expanded, and the separated semiconductor wafer 2 (that is, the semiconductor chip 1) is formed. Pick up one by one with the separated adhesive layer 13 Extent and (expanding step and the pickup step), a has.
Accordingly, the dicing die bonding tape 10 is used, and the support base material 12a of the dicing die bonding tape 10 is cut in the thickness direction by 10 μm or more in the dicing process, so that the semiconductor chips 2 can be more easily bonded to each other at the time of pickup. It is possible to more sufficiently suppress the occurrence of double die error.

Moreover, according to the semiconductor processing method using the dicing die bonding tape 10 described above, the thickness of the support base material 12a is 60 μm or more, and in the step of dividing into pieces (dicing step), the support base material 12a is formed. It is designed to cut 10 to 30 μm in the thickness direction.
Therefore, since the thickness of the support base material 12a is 60 μm or more and the support base material 12a is cut in the thickness direction by 10 to 30 μm in the dicing step, the strength enough to prevent the support base material 12a from breaking even when the dicing tape 12 is expanded. And the re-adhesion between the semiconductor chips 2 at the time of pickup can be suppressed almost completely.

  Next, examples of the present invention will be described, but the present invention is not limited to these examples.

First, while preparing support base material (base film) AK and adjusting an adhesive composition, it adjusts so that the thickness after drying of an adhesive composition may be set to 20 micrometers on a support base material. The pressure-sensitive adhesive composition thus applied was applied and dried at 110 ° C. for 3 minutes to prepare a pressure-sensitive adhesive sheet (dicing tape) having a pressure-sensitive adhesive layer formed on a supporting substrate.
Next, the adhesive composition was prepared and applied to the release liner made of a polyethylene-terephthalate film from which the adhesive composition was released so that the thickness after drying was 60 μm. And dried at 110 ° C. for 3 minutes to form an adhesive film (adhesive layer) on the release liner.
And after cutting the produced adhesive sheet and adhesive film into the shape shown in FIG. 1, the adhesive film is bonded to the adhesive layer side of the adhesive sheet to produce samples of Examples 1 to 5 and Comparative Examples 1 to 6. did.
Below, the preparation methods of support base material AK, the adjustment method of an adhesive composition and an adhesive composition are shown.

(Preparation of support substrate A)
A resin bead of ethylene-methacrylic acid binary copolymer zinc ionomer having a weight fraction of methacrylic acid component of 1% and a neutralization degree of the methacrylic acid of 60% is melted at 140 ° C. and thickened using an extruder. A support base A was obtained by forming into a 100 μm long film.

(Preparation of support substrate B)
A resin bead of ethylene-methacrylic acid binary copolymer zinc ionomer having a weight fraction of methacrylic acid component of 3% and a degree of neutralization of the methacrylic acid of 50% is melted at 140 ° C. and thickened using an extruder. A support base B was obtained by forming into a 100 μm long film.

(Preparation of support substrate C)
A resin bead of ethylene-methacrylic acid binary copolymer zinc ionomer having a methacrylic acid component weight fraction of 5% and a methacrylic acid neutralization degree of 50% is melted at 140 ° C. and thickened using an extruder. A support substrate C was obtained by forming into a 100 μm long film.

(Preparation of support substrate D)
A resin bead of ethylene-methacrylic acid binary copolymer zinc ionomer having a methacrylic acid component weight fraction of 9% and a neutralization degree of the methacrylic acid of 60% is melted at 140 ° C. and thickened using an extruder. A support base D was obtained by forming into a 100 μm long film.

(Preparation of support substrate E)
Ethylene-methacrylic acid-butyl methacrylate terpolymer having a methacrylic acid component weight fraction of 9%, a methacrylic acid butyl ester component weight fraction of 12%, and a neutralization degree of the methacrylic acid of 70%. Zinc ionomer resin beads were melted at 140 ° C. and formed into a long film having a thickness of 100 μm using an extruder, whereby a supporting substrate E was obtained.

(Preparation of support substrate F)
A resin bead of ethylene-methacrylic acid binary copolymer zinc ionomer having a methacrylic acid component weight fraction of 10% and a neutralization degree of the methacrylic acid of 60% is melted at 140 ° C. and thickened using an extruder. A support base F was obtained by forming into a 100 μm long film.

(Preparation of support base G)
A resin bead of commercially available low density polyethylene (Petrocene 217: manufactured by Tosoh Corporation) with a methacrylic acid component weight fraction of 0% is melted at 140 ° C. and formed into a long film with a thickness of 100 μm using an extruder. The support base material G was obtained by molding.

(Preparation of support substrate H)
An ethylene-methacrylic acid binary copolymer resin bead having a methacrylic acid component weight fraction of 5% and a neutralization degree of the methacrylic acid of 0% is melted at 140 ° C., and the thickness is 100 μm using an extruder. A support base material H was obtained.

(Preparation of support substrate I)
A resin bead of ethylene-methacrylic acid butyl methacrylate terpolymer having a methacrylic acid component weight fraction of 9% and a neutralization degree of the methacrylic acid of 0% is melted at 140 ° C., and an extruder is used. A support film I was obtained by forming into a long film having a thickness of 100 μm.

(Preparation of support substrate J)
A resin bead of ethylene-methacrylic acid binary copolymer zinc ionomer having a weight fraction of methacrylic acid component of 1% and a neutralization degree of methacrylic acid of 30% is melted at 140 ° C. and thickened using an extruder. A support base J was obtained by forming into a 100 μm long film.

(Preparation of support substrate K)
A resin bead of ethylene-methacrylic acid binary copolymer zinc ionomer having a weight fraction of methacrylic acid component of 5% and a neutralization degree of the methacrylic acid of 40% is melted at 140 ° C. and thickened using an extruder. A support base K was obtained by forming into a 100 μm long film.

(Adjustment of adhesive composition)
20 weight of trimethylolpropane trimethacrylate as a compound having a radiation curable carbon-carbon double bond to an n-butyl acrylate / 2-hydroxyethyl methacrylate copolymer (average molecular weight 500,000, glass transition temperature -40 ° C.) And 7 parts by weight of polyisocyanate compound coronate L (trade name, manufactured by Nippon Polyurethane Co., Ltd.) as a curing agent, and 5 parts by weight of Irgacure 184 (trade name, manufactured by Nippon Ciba-Geigy Co., Ltd.) as a photopolymerization initiator A curable pressure-sensitive adhesive composition was obtained.

(Adjustment of adhesive composition)
As a compound having an epoxy group, 100 parts by weight of a cresol novolac type epoxy resin is added to 100 parts by weight of an acrylic copolymer (glycidyl acrylate type copolymer), and further an epoxy curing agent is added to 10 parts by weight of a xylene novolac type phenol resin. As a mixture, 5 parts by weight of 2-phenylimidazole and 0.5 parts by weight of xylenediamine were blended, and 60 parts by weight of nanosilica filler having an average particle size of 0.012 μm was added to obtain an adhesive composition.

<Example 1>
The adjusted pressure-sensitive adhesive composition was applied to the support substrate A to prepare a dicing tape, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Example 1.

<Example 2>
The adjusted pressure-sensitive adhesive composition was applied to the support substrate B to prepare a dicing tape, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Example 2.

<Example 3>
A dicing tape was prepared by applying the adjusted pressure-sensitive adhesive composition to the support substrate C, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Example 3.

<Example 4>
A dicing tape was prepared by applying the adjusted pressure-sensitive adhesive composition to the support substrate D, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Example 4.

<Example 5>
A dicing tape was prepared by applying the adjusted pressure-sensitive adhesive composition to the support substrate E, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Example 5.

<Comparative Example 1>
A dicing tape was prepared by applying the adjusted pressure-sensitive adhesive composition to the support substrate F, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Comparative Example 1.

<Comparative example 2>
A dicing tape was prepared by applying the adjusted pressure-sensitive adhesive composition to the support base G, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Comparative Example 2.

<Comparative Example 3>
The adjusted pressure-sensitive adhesive composition was applied to the supporting substrate H to prepare a dicing tape, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Comparative Example 3.

<Comparative example 4>
The adjusted pressure-sensitive adhesive composition was applied to the support substrate I to prepare a dicing tape, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Comparative Example 4.

<Comparative Example 5>
A dicing tape was prepared by applying the adjusted pressure-sensitive adhesive composition to the support substrate J, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Comparative Example 5.

<Comparative Example 6>
A dicing tape was prepared by applying the adjusted pressure-sensitive adhesive composition to the support substrate K, and the adjusted adhesive composition was laminated on the dicing tape to prepare a sample of Comparative Example 6.

<Evaluation method>
(Pickup test)
A silicon wafer having a thickness of 50 μm and a diameter of 200 mm was heated and bonded to each sample of Examples 1 to 5 and Comparative Examples 1 to 6 at 70 ° C., and was diced into a size of 5 mm × 5 mm using a dicing apparatus (DFD 6340 manufactured by Disco). did. At that time, the adhesive layer and the pressure-sensitive adhesive layer of the dicing die bonding tape were cut and divided, and the apparatus was adjusted so that the supporting base material was cut at a predetermined depth (0 μm, 10 μm, 20 μm) in the thickness direction.
Next, each sample that had been diced was irradiated with ultraviolet rays of 200 mJ / cm ² using a metal halide lamp.
After that, for each sample, using a pickup device (CAP-300II manufactured by Canon Machinery), 100 times for each sample with 5% expansion added to the dicing tape of each sample by the method shown in FIG. Attempts were made to pick up, and among them, cases where individual semiconductor chips could be picked up were counted as successes. Cases where two or more semiconductor chips were reattached and picked up were counted as failures.
The evaluation results are shown in Tables 1 and 2.

From the results in Table 1, the weight fraction of the (meth) acrylic acid component in the copolymer in the support substrate is 1% or more and less than 10%, and the degree of neutralization of (meth) acrylic acid in the ionomer resin is the sample satisfies examples 1-5 that is 50% or more, when cutting the supporting Jimotozai, it was found that the occurrence of re-adhesion during pickup is suppression. In particular, it was found that when the support base material was cut in the thickness direction by 20 μm, the occurrence of re-adhesion during pick-up could be completely suppressed.
On the other hand, from the results of Table 2, the weight fraction of the (meth) acrylic acid component in the copolymer in the support substrate is 1% or more and less than 10%, and the (meth) acrylic acid in the ionomer resin In the samples of Comparative Examples 1 to 6 that do not satisfy the condition that the degree of neutralization is 50% or more, when the supporting base material is not cut, the same degree as when the supporting base materials of the samples of Examples 1 to 5 are not cut. It was also found that re-adhesion occurs at the time of pick-up at a rate higher than that, and re-adhesion occurs at the time of pick-up even if the support substrate is cut.
From the above, the weight fraction of the (meth) acrylic acid component in the copolymer in the support substrate is 1% or more and less than 10%, and the degree of neutralization of (meth) acrylic acid in the ionomer resin is 50% or more. If so, it can be seen that the occurrence of a double die error can be sufficiently suppressed. Furthermore, it turns out that generation | occurrence | production of a double die error can be further suppressed if a support base material is cut 10 micrometers or more in the thickness direction.

1 semiconductor wafer 2 semiconductor chip 10 dicing die bonding tape (wafer processing tape)
11 Release liner 12 Dicing tape (adhesive tape)
12a Support substrate 12b Adhesive layer 13 Adhesive layer 20 Ring frame 21 Thin grindstone 22 Adsorption stage 30 Push-up member 31 Pin 32 Adsorption jig

Claims (4)

When a thermosetting adhesive layer containing a compound having an epoxy group is laminated on the pressure-sensitive adhesive layer of a pressure-sensitive adhesive tape composed of a support substrate and a pressure-sensitive adhesive layer, and the bonded semiconductor wafer is separated into pieces In the wafer processing tape in which the semiconductor wafer, the adhesive layer and the pressure-sensitive adhesive layer are cut, and the support base material is cut to a predetermined depth in the thickness direction ,
The supporting substrate is made of an ionomer resin obtained by crosslinking an ethylene- (meth) acrylic acid binary copolymer or an ethylene- (meth) acrylic acid- (meth) acrylic acid alkyl ester ternary copolymer with a metal ion. ,
The weight fraction of the (meth) acrylic acid component in the copolymer is 1% or more and less than 10%, and the degree of neutralization of the (meth) acrylic acid in the ionomer resin is 50% or more. A tape for wafer processing, characterized in that there is.   2. The wafer processing tape according to claim 1, wherein the pressure-sensitive adhesive layer has a structure of one layer or two or more layers, and at least one of them is formed of an energy ray-curable pressure-sensitive adhesive. In the semiconductor processing method using the wafer processing tape according to claim 1 or 2,
Bonding the semiconductor wafer to the wafer processing tape;
Next, the semiconductor wafer and the adhesive layer and the pressure-sensitive adhesive layer of the wafer processing tape are cut using a thin grindstone that rotates at high speed, and the supporting base material of the wafer processing tape is 10 μm in the thickness direction. Cutting the semiconductor wafer and the adhesive layer into pieces,
Next, in a state where the adhesive tape of the wafer processing tape is expanded, the step of picking up the semiconductor wafers that are separated into pieces,
A semiconductor processing method characterized by comprising: The support substrate has a thickness of 60 μm or more,
The semiconductor processing method according to claim 3, wherein in the step of dividing into pieces, the support base material is cut in a thickness direction by 10 to 30 μm.