JP6159220B2 - Stripping composition and stripping method - Google Patents

Description

  The present invention relates to a peeling composition and a peeling method.

  In recent years, with the enhancement of functions of mobile phones, digital AV devices, IC cards, and the like, there is an increasing demand for miniaturization, thinning and high integration of semiconductor silicon chips. For example, a system-in-package (SiP) in which multiple semiconductor chips are mounted in a single semiconductor package makes the mounted chips smaller, thinner and more integrated, and electronic devices have higher performance and smaller size. In addition, it has become a very important technology for realizing weight reduction. In order to meet such demands for thinning and high integration, not only conventional wire bonding technology, but also through electrode technology that stacks chips with through electrodes and forms bumps on the back of the chip I need it.

  By the way, in the manufacture of semiconductor chips, the semiconductor wafer itself is thin and fragile, and the circuit pattern has irregularities, so that it is easily damaged when an external force is applied during conveyance to the grinding process or dicing process. Therefore, a wafer handling system has been developed that maintains the strength of the wafer and prevents the occurrence of cracks and warpage of the wafer by bonding a plate made of glass, hard plastic or the like called a support plate to the wafer to be ground. . Since the wafer strength can be maintained by the wafer handling system, the transport of the thinned semiconductor wafer can be automated.

  The wafer and the support plate are bonded together using an adhesive tape, a thermoplastic resin, an adhesive, or the like. After thinning the wafer to which the support plate is attached, the support plate is peeled from the substrate before dicing the wafer. For example, when the wafer and the support plate are bonded together using the dissolution type adhesive described in Patent Document 1, the wafer is supported after the adhesive layer formed from the adhesive is dissolved by the peeling composition. Peeling from the plate.

JP 2012-092283 A (released May 17, 2012) Special Publication 2004-524431 (Announced August 12, 2004)

  However, the conventional peeling composition may not have sufficient solubility in an adhesive layer formed with an adhesive as described in Patent Document 1. For example, when a peeling composition that is not sufficiently soluble in the adhesive layer formed to temporarily fix the wafer and the support plate in the wafer handling system is used, the wafer may be damaged due to poor peeling or the wafer may be damaged. Adhesive residue may remain on top.

  Moreover, patent document 2 does not disclose about the peeling composition which can melt | dissolve an adhesive rapidly.

  This invention is made | formed in view of such a situation, and makes it the main subject to provide the peeling composition for peeling the adhesive agent which can melt | dissolve an adhesive agent rapidly.

In order to solve the above problems, a peeling composition according to the present invention is a peeling composition for peeling an adhesive,
The following chemical formula (I)

It includes a trans form of a compound having a skeleton represented by

  Further, the peeling method according to the present invention includes a support, a substrate supported by the support, and the substrate in a laminate including the support and the adhesive layer to which the substrate is bonded. A method of peeling the support, characterized in that it includes a contact step of bringing the peeling composition according to the present invention into contact with the adhesive layer.

  ADVANTAGE OF THE INVENTION According to this invention, the composition for peeling for peeling an adhesive agent which can melt | dissolve an adhesive agent rapidly can be provided.

It is a graph which shows the dissolution rate ratio of the adhesive agent by a peeling composition.

[Peeling composition]
The stripping composition according to the present invention is a stripping composition for stripping an adhesive and has the following chemical formula (I)

A trans isomer of a compound having a skeleton represented by

  Thus, since the peeling composition according to the present invention includes a trans isomer of a compound having a skeleton represented by the chemical formula (I), it is possible to quickly dissolve the adhesive to be peeled. Moreover, if the purity and isomer ratio of the compound of the above chemical formula (I) are controlled, the solubility of the adhesive can be stably maintained.

  In the stripping composition according to the present invention, the compound may be a derivative into which another substituent is introduced with the skeleton represented by the chemical formula (I) as a basic skeleton. Examples of the derivative include 1-methyldecalin, 1-ethyldecalin, decalin-1-one, decalin-2-one, decalin-1-ol, decalin-4-ol, and the like. In addition, the peeling composition which concerns on this invention may contain the compound illustrated here independently, and may contain 2 or more types together.

  The stripping composition according to the present invention is more preferably decahydronaphthalene as the compound having a skeleton represented by the chemical formula (I). With decahydronaphthalene, the dissolution rate with respect to the adhesive, in particular, the dissolution rate with respect to the hydrocarbon-based adhesive becomes higher.

  In the stripping composition according to the present invention, the purity of the compound having a skeleton represented by the chemical formula (I) is preferably 95% or more, more preferably 98% or more, and 99% or more. Is more preferable. When the purity is 95% or more, more stable solubility can be maintained, and the adhesive can be dissolved without causing poor peeling of the adhesive.

  “Purity” means a value determined by mass conversion of the total amount of trans and cis forms of a compound detected using gas chromatography (GC) unless otherwise specified.

  The stripping composition according to the present invention only needs to contain a trans isomer of a compound having a skeleton represented by the above chemical formula (I). Here, the trans / cis ratio of the compound is more preferably 1.0 or more, further preferably 1.5 or more, and particularly preferably 3.0 or more. In addition, when two or more compounds having a skeleton represented by the above chemical formula (I) are included, the purity and trans / cis ratio of the total of the trans isomer and cis isomer of the two or more compounds included are included. What is necessary is just to obtain | require as ratio.

The “trans / cis ratio” of the compound having the skeleton represented by the above chemical formula (I) is the peak in each chemical shift of the ¹ H-NMR trans isomer and the cis isomer, or the trans isomer of GC unless otherwise specified. And the ratio determined based on the peaks at the respective retention times of the cis isomers.

  In the stripping composition according to the present invention, the ratio of the trans isomer of the compound having the skeleton represented by the chemical formula (I) is 50% by weight when the total of the trans isomer and the cis isomer is 100% by weight. Preferably, it is 60% by weight or more, more preferably 75% by weight or more. If the trans body is contained in an amount of 50% by weight or more, stable solubility can be obtained, and the adhesive can be peeled off more rapidly.

  In the peeling composition according to the present invention, the adhesive to be peeled is not particularly limited, but a hydrocarbon adhesive is more preferable.

  The stripping composition according to the present invention can dissolve the hydrocarbon-based adhesive more rapidly and can reduce the residue.

  Examples of the hydrocarbon adhesive include an adhesive containing a cycloolefin copolymer and a styrene elastomer.

  The stripping composition according to the present invention may contain other components as long as the effects of the present invention are not impaired.

  As a use of the peeling composition according to the present invention, it can be used for separating a temporarily bonded laminate used in the production of various products. For example, in a wafer handling system, after a semiconductor wafer is temporarily fixed to a support plate and subjected to various processing treatments, the support plate is suitably used for peeling from the semiconductor wafer. It is possible to prevent the adhesive residue from remaining on the wafer.

[Method for producing stripping composition]
The peeling composition according to the present invention is not particularly limited, but may be arbitrarily prepared from, for example, a commercially available or natural compound having a skeleton represented by the above chemical formula (I). Further, for example, a peeling composition produced by hydrogenating naphthalene or a naphthalene derivative and containing a compound having a target purity and trans / cis ratio may be prepared. The stripping composition containing decahydronaphthalene, which is a water additive of naphthalene, may contain a partial water additive such as tetrahydronaphthalene.

  Examples of the method for adjusting the trans / cis ratio and purity of the compound having a skeleton represented by the chemical formula (I) include distillation. Further, a distillation treatment may be performed to adjust the purity. Moreover, you may prepare the peeling composition by mixing the compound of the said Chemical formula (I) which consists only of a trans body, and the compound of the said Chemical formula (I) which consists only of a cis body in arbitrary ratios.

[Peeling method]
The peeling method according to the present invention includes a support, a substrate supported by the support, and the support in the laminate including the support and the adhesive layer bonding the substrate. A method for peeling a body, which includes a contact step of bringing the peeling composition according to the present invention into contact with the adhesive layer.

  Since the peeling method according to the present invention uses a peeling composition containing a trans isomer of a compound having a skeleton represented by the chemical formula (I), it is possible to quickly dissolve an adhesive to be peeled. For this reason, the peeling defect of an adhesive agent can be prevented. Accordingly, it is possible to prevent the substrate from being damaged due to poor peeling of the adhesive.

  Here, in the peeling method according to the present invention, the peeling composition may be prepared so that the purity of the compound of the chemical formula (I) and the ratio of the trans isomer are increased. Thereby, the solubility of the composition for peeling with respect to an adhesive agent can be improved more, and the peeling defect of an adhesive agent can be prevented.

  Moreover, you may adjust conditions, such as the processing time in a contact process, based on the ratio of the trans body in the compound of the said chemical formula (I) used for a peeling composition. Thereby, based on the composition for peeling, the suitable conditions for peeling an adhesive agent can be calculated | required. Accordingly, it is possible to stably maintain the solubility of the adhesive and prevent the adhesive from being peeled off.

  The laminate is formed in order to maintain the strength of the substrate in the wafer handling system, and is a support, a substrate supported by the support, and an adhesive bonding the support and the substrate together. With layers.

  The support is, for example, a member that plays a role of supporting the substrate in the process of thinning the substrate, and is bonded to the substrate with an adhesive. The support is made of glass or silicon having a thickness of 500 to 1000 μm, for example. The support may be provided with a hole penetrating the support in the thickness direction.

  Examples of the substrate include a semiconductor wafer that is a conventionally known material.

  An adhesion layer is a member for bonding a support body and a board | substrate, and is formed with the adhesive agent which the composition part for peeling which concerns on this invention makes peeling object. The adhesive to be peeled is more preferably a hydrocarbon adhesive.

(Contact process)
In the contact step included in the peeling method according to the present invention, the peeling composition according to the present invention is brought into contact with the adhesive layer. As a method for bringing the peeling composition into contact with the adhesive layer, for example, the peeling composition according to the present invention is brought into contact with the adhesive between the substrate and the support by means of a spray or a dispensing nozzle. A method can be mentioned. As a result, the adhesive is dissolved to peel the substrate from the support, and the substrate surface peeled from the support is washed and dried. If the substrate thus obtained is subjected to subsequent processing, no liquid trace residue is produced on the substrate surface, so that it is possible to prevent a decrease in electrical characteristics and a decrease in yield of the substrate.

  If a hole penetrating in the thickness direction of the support is provided, when the substrate is peeled from the support, the peeling composition according to the present invention is interposed between the support plate and the substrate through the hole. Can be poured into. For this reason, the composition for peeling can be made to contact an adhesive agent efficiently, and an adhesive layer can be dissolved more suitably. For this reason, a board | substrate can be more easily peeled from a support plate.

  In addition, for example, when the adhesive layer is formed of a separation layer and an adhesive that are altered by laser irradiation, the support plate is first peeled from the wafer by laser irradiation, and then the adhesive residue remaining on the wafer is removed. You may melt | dissolve and remove with the peeling composition of this invention.

  The present invention includes not only a method of peeling the substrate and the support using the peeling composition according to the present invention, but also a substrate processing method such as forming an electrode on the substrate peeled from the support.

  Examples will be shown below, and the embodiments of the present invention will be described in more detail. Of course, the present invention is not limited to the following examples, and it goes without saying that various aspects are possible in detail. Further, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims, and the present invention is also applied to the embodiments obtained by appropriately combining the disclosed technical means. It is included in the technical scope of the invention. Moreover, all the literatures described in this specification are used as reference.

[Peel test]
(Preparation of materials)
As an object to be peeled used in the peeling test, the following chemical formula (II)

  (In the formula, m: n = 80: 20 (molar ratio)) is dissolved in decahydronaphthalene so that the concentration after dissolution is 25%. Thus, an adhesive composition was prepared. With respect to the peelability of this adhesive composition, the peelability of the stripping compositions of Examples 1 to 7 and Comparative Example 1 in which the proportion of the trans isomer was different in decahydronaphthalene having a purity of 99% was evaluated. The purity and the trans ratio of the stripping compositions of Examples 1 to 7 and Comparative Example 1 are shown in Table 1 below.

  “Purity” in Table 1 was measured using gas chromatography (manufactured by Agilent, product name “Technologies”).

“Trans: cis” in Table 1 is the result of calculating the ratio (mass ratio) of the trans isomer and cis isomer in decahydronaphthalene by ¹ H-NMR (manufactured by BRUKER, product name “AVANCE-600”). It is. From the ratio, the “trans / cis ratio” is calculated. For reference, the “trans / cis ratio” of Example 2 is 4.0, which is 4.0 (4.0 / 1 = 4.0).

  The “trans isomer ratio” in Table 1 indicates the ratio of the trans isomer contained in decahydronaphthalene, and is calculated from the above-mentioned “trans: cis”.

(Evaluation of solubility)
The peelability of the stripping composition was evaluated based on the dissolution rate with respect to the adhesive. Specifically, the above adhesive composition was spin-coated on a 12-inch silicon substrate, and baked at 100 ° C., 160 ° C., and 220 ° C. for 3 minutes to form an adhesive layer (film thickness: 15 μm). Only this adhesive layer (coating film) was immersed in the stripping composition at room temperature (23 ° C.), and the end point was when the adhesive layer on the silicon substrate was completely dissolved. The dissolution rate was calculated by peeling film thickness (nm) / peeling time (second (s)). The results are shown in Table 2 and FIG. FIG. 1 is a graph showing the dissolution rate ratio of the adhesive by the peeling composition, where the vertical axis indicates the dissolution rate ratio (%), and the horizontal axis indicates the proportion (%) of the trans form of decahydronaphthalene. The “dissolution rate ratio” in FIG. 1 and Table 2 is calculated on the basis of the dissolution rate of the peeling composition (Comparative Example 1) made of decahydronaphthalene having a cis isomer ratio of 100%.

  As shown in Table 2, in the stripping compositions of Examples 1 to 7, a good dissolution rate can be obtained as compared with the stripping composition (Comparative Example 1) composed of decahydronaphthalene having only a cis form. It was. From this, the peeling composition of Examples 1-7 containing the trans form of decahydronaphthalene can dissolve the adhesive more rapidly than the peeling composition of Comparative Example 1 containing no trans form. I was able to confirm. Moreover, as shown in FIG. 1 and Table 2, in Examples 1-7, the dissolution rate became faster and the dissolution rate ratio tended to increase as the proportion of the trans isomer increased. In particular, in Example 4 where the proportion of the trans form of decahydronaphthalene was 50%, a dissolution rate ratio of 120% or more was obtained with respect to Comparative Example 1.

(Evaluation of peelability)
Then, the laminated body was produced using the above-mentioned adhesive composition, and the peelability when peeling a support body from the board | substrate of the said laminated body was evaluated. For the evaluation of peelability, the stripping composition of Example 4 and the stripping composition of Comparative Example 1 were used.

  The adhesive composition solution was spin-coated on a 12-inch silicon substrate, and baked at 100 ° C., 160 ° C., and 220 ° C. for 3 minutes to form an adhesive layer (film thickness: 15 μm). Next, this silicon substrate was bonded to a perforated glass support (12 inches) through an adhesive layer while heating at 215 ° C. to prepare a laminate.

  Peeling of the support from the substrate in the laminate is performed after the semiconductor wafer substrate thinning process, the photolithography process, and the like, and then the peeling compositions of Example 4 and Comparative Example 1 are removed from the holes of the glass support. This was done by pouring, dissolving the adhesive composition and removing the glass support.

  Compared with the peeling composition of Comparative Example 1, the peeling composition of Example 4 had a faster dissolution rate of the adhesive, and was able to peel the glass support more easily from the semiconductor wafer substrate.

[Evaluation of cleanability]
Next, the silicon substrate from which the glass support was peeled was spray-washed using the peeling composition of Example 4 and Comparative Example 1, and the detergency was evaluated by determining the presence or absence of the adhesive layer residue. As a result, no adhesive residue was observed on the semiconductor wafer substrate from which the glass support was peeled off using the peeling composition of Example 4, and good cleanability could be obtained.

  The stripping composition of the present invention can be used to separate a temporarily bonded laminate used in the production of various products. In particular, it can be suitably used in a manufacturing process in which a semiconductor wafer or chip is temporarily fixed to various supports and processed.

Claims (5)

A stripping composition for stripping an adhesive,
The following chemical formula (I)

In looking containing the trans isomer of a compound having a skeleton represented,
A stripping composition, wherein the purity of the compound is 95% or more . The stripping composition according to claim 1 , wherein the ratio of the trans isomer of the compound is 50% or more when the total of the trans isomer and the cis isomer of the compound is 100%. The stripping composition according to claim 1 or 2 , wherein the compound is decahydronaphthalene. The peeling composition according to any one of claims 1 to 3 , wherein the adhesive to be peeled is a hydrocarbon-based adhesive. A method of peeling the support from the substrate in a laminate comprising a support, a substrate supported by the support, and an adhesive layer bonding the support and the substrate. ,
The peeling method characterized by including the contact process which makes the said adhesive layer contact the peeling composition of any one of Claims 1-4 .

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