JP6009860B2 - Manufacturing method of semiconductor device - Google Patents

Description

The present invention relates to a method for manufacturing a semiconductor device capable of suppressing voids and realizing high reliability.

In recent years, flip-chip mounting using a semiconductor chip having protruding electrodes (bumps) made of solder or the like is frequently used in order to cope with miniaturization and high integration of a semiconductor device that is increasingly developed.
In flip-chip mounting, a method is generally used in which a protruding electrode of a semiconductor chip and an electrode portion of a substrate or another semiconductor chip are joined and then an underfill is injected to perform resin sealing. . However, in recent years, semiconductor chips have been miniaturized, and the pitch between the protruding electrodes has become narrower. In addition, the gap between the semiconductor chips or between the semiconductor chip and the substrate has become narrower. For this reason, air is entrained when the underfill is injected, and voids are easily generated.

In order to suppress voids, a method of supplying a bonding material in advance to a substrate or a semiconductor chip is used instead of injecting an underfill after bonding of the protruding electrodes. Such a method is generally performed using a flip chip bonder. However, in such a method, since the bonding of the protruding electrodes and the curing of the bonding material are simultaneously performed by heating, it is not easy to achieve both the bonding of the protruding electrodes with high accuracy and the suppression of voids.

In order to improve production efficiency, a method using only a reflow apparatus capable of mass production without using a flip chip bonder has been studied. For example, in Patent Document 1, a predetermined liquid bonding material composition is applied to a position where a semiconductor element on a circuit forming surface of an inorganic substrate or an organic substrate is mounted, and then an electrode of the semiconductor element and a circuit of the substrate are reflowed. A manufacturing method of a semiconductor device is described in which the liquid bonding material composition is cured at the same time as bonding through bumps in a furnace.

In the method described in Patent Document 1, reflow preheating at a temperature lower than the melting point of solder and reflow main heating at a temperature higher than the melting point of solder are performed. At the time of preheating, the liquid bonding material composition has a sufficiently low viscosity, and the connection electrode portion of the semiconductor element and the printed circuit board come into contact with each other only by the weight of the semiconductor element. Thereafter, the connecting electrode portion is melted by this heating and soldered to the electrode of the printed circuit board, and the liquid bonding material composition is cured after the solder bonding.
However, in such a method, since the viscosity of the liquid bonding material composition at the time of preheating is low, when the substrate is warped, the liquid bonding material composition flows to the electrode part before bonding. Deviation may occur, and deviation may occur in the electrode part before joining due to vibration or wind pressure of the reflow furnace. In addition, the possibility of voids due to such a flow of the liquid bonding material composition, displacement of the electrode portion, foaming of the liquid bonding material composition during heating, etc. has not been sufficiently eliminated.

JP 2009-96886 A

An object of this invention is to provide the manufacturing method of the semiconductor device which can implement | achieve high reliability by suppressing a void.

The present invention includes an alignment step of aligning a semiconductor chip on which a protruding electrode having a tip portion made of solder is formed on a substrate through a bonding material, and heating the semiconductor chip to a temperature equal to or higher than a solder melting point. An electrode bonding step for melting and bonding the protruding electrode of the semiconductor chip and the electrode portion of the substrate, and heating the bonding material having a curing rate of 40% or less in a pressurized atmosphere with a curing rate of the material of 40% or less And a void removing step of removing the void.
The present invention is described in detail below.

In the method in which the inventor melts the protruding electrode of the semiconductor chip and the electrode portion of the substrate by heating to a temperature equal to or higher than the solder melting point and then cures the bonding material, Even if air is entrained in the bonding material by performing a void removal step in which the curing rate of the bonding material is set to a predetermined value or less and then heated in a pressurized atmosphere to remove voids. The present invention has been completed by finding that it can be removed and that electrode bonding can be performed well to achieve high reliability. By performing the void removing step, it is considered that not only the voids are not grown but also actively removed.

In the method for manufacturing a semiconductor device of the present invention, first, an alignment process is performed in which a semiconductor chip on which a protruding electrode made of solder is formed is aligned on a substrate via a bonding material. Such an alignment process is generally performed using a mounting apparatus such as a flip chip bonder.

Examples of the semiconductor chip include a semiconductor chip made of a semiconductor such as silicon or gallium arsenide and having a protruding electrode having a tip portion made of solder formed on the surface. Note that the protruding electrode having the tip made of solder may have the entire protruding electrode made of solder as long as it has the tip made of solder.

The method for supplying the bonding material is not particularly limited. For example, after a sheet-shaped bonding material is applied to a wafer in advance or a paste-shaped bonding material is applied or printed to form a coating film, a semiconductor chip is then formed. A method of dividing into pieces, a method of sticking a sheet-like bonding material on a substrate or a semiconductor chip, filling a syringe with a paste-like bonding material, attaching a precision nozzle to the tip of the syringe, and using a dispenser device on the substrate And a method of discharging the ink.

The bonding material is designed so that the curing rate is 40% or less when the protruding electrode of the semiconductor chip and the electrode portion of the substrate are melt bonded. The bonding material may be in the form of a sheet or a paste, and preferably contains a curable compound and a curing agent. The combination of the curable compound and the curing agent can control the curability of the bonding material.
The said curable compound is not specifically limited, For example, the compound hardened | cured by reaction, such as addition polymerization, polycondensation, polyaddition, addition condensation, ring-opening polymerization, is mentioned. Specific examples of the curable compound include urea resin, melamine resin, phenol resin, resorcinol resin, epoxy resin, acrylic resin, polyester resin, polyamide resin, polybenzimidazole resin, diallyl phthalate resin, xylene resin, alkyl- Examples thereof include thermosetting compounds such as benzene resin, epoxy acrylate resin, silicon resin, and urethane resin. Especially, since it is excellent in the reliability and joining strength of a semiconductor device, an epoxy resin and an acrylic resin are preferable and the epoxy resin which has an imide skeleton is more preferable.

The epoxy resin is not particularly limited. For example, bisphenol type epoxy resins such as bisphenol A type, bisphenol F type, bisphenol AD type and bisphenol S type, novolac type epoxy resins such as phenol novolak type and cresol novolak type, resorcinol type epoxy Resin, aromatic epoxy resin such as trisphenolmethane triglycidyl ether, naphthalene type epoxy resin, fluorene type epoxy resin, dicyclopentadiene type epoxy resin, polyether modified epoxy resin, NBR modified epoxy resin, CTBN modified epoxy resin, and These hydrogenated products can be mentioned. Among them, bisphenol F type epoxy resin, resorcinol type epoxy resin, and polyether-modified epoxy resin are preferable because a bonding material having a low viscosity can be obtained.

Among the bisphenol F-type epoxy resins, as commercial products, for example, EXA-830-LVP, EXA-830-CRP (manufactured by DIC) and the like can be mentioned. Moreover, EX-201 (made by Nagase ChemteX Corporation) etc. are mentioned as a commercial item among the said resorcinol type epoxy resins. Moreover, as a commercial item among the said polyether modified epoxy resins, EX-931 (made by Nagase ChemteX), EXA-4850-150 (made by DIC), EP-4005 (made by ADEKA) etc. are mentioned, for example. It is done. Moreover, as a commercial item among the said dicyclopentadiene type epoxy resins, HP-7200HH (made by DIC), EP-4088L (made by Adeka) etc. are mentioned, for example.

The above-mentioned curable compound has a preferable upper limit of moisture absorption of 1.5% and a more preferable upper limit of 1.1%. Examples of the curable compound having such a moisture absorption rate include naphthalene type epoxy resins, fluorene type epoxy resins, dicyclopentadiene type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins and the like.

The said hardening | curing agent is not specifically limited, A conventionally well-known hardening | curing agent can be suitably selected according to the said sclerosing | hardenable compound. When using an epoxy resin as the curable compound, examples of the curing agent include latent heat-curing acid anhydride-based curing agents such as trialkyltetrahydrophthalic anhydride, phenol-based curing agents, amine-based curing agents, and dicyandiamide. For example, a cationic curing agent and a cationic catalyst-type curing agent. These curing agents may be used alone or in combination of two or more.

Although the compounding quantity of the said hardening | curing agent is not specifically limited, When using the hardening | curing agent which reacts equally with the functional group of the said sclerosing | hardenable compound, it is 60-100 equivalent with respect to the functional group amount of the said sclerosing | hardenable compound. preferable. Moreover, when using the hardening | curing agent which functions as a catalyst, as for the compounding quantity of the said hardening | curing agent, a preferable minimum is 1 weight part with respect to 100 weight part of said curable compounds, and a preferable upper limit is 20 weight part.

The bonding material may contain a curing accelerator in addition to the curing agent in order to adjust the curing speed, physical properties of the cured product, and the like.
The said hardening accelerator is not specifically limited, For example, an imidazole series hardening accelerator, a tertiary amine type hardening accelerator, etc. are mentioned. Of these, an imidazole curing accelerator is preferred because it is easy to control the reaction system for adjusting the curing speed and the physical properties of the cured product. These hardening accelerators may be used independently and may use 2 or more types together.

The imidazole-based curing accelerator is not particularly limited. For example, 1-cyanoethyl-2-phenylimidazole in which the 1-position of imidazole is protected with a cyanoethyl group, an imidazole-based curing accelerator whose basicity is protected with isocyanuric acid (trade name “ 2MA-OK ", manufactured by Shikoku Kasei Kogyo Co., Ltd.), 2MZ, 2MZ-P, 2PZ, 2PZ-PW, 2P4MZ, C11Z-CNS, 2PZ-CNS, 2PZCNS-PW, 2MZ-A, 2MZA-PW, C11Z-A, 2E4MZ-A, 2MAOK-PW, 2PZ-OK, 2MZ-OK, 2PHZ, 2PHZ-PW, 2P4MHZ, 2P4MHZ-PW, 2E4MZ · BIS, VT, VT-OK, MAVT, MAVT-OK (above, Shikoku Chemical Industries, Ltd. Manufactured), Fuji Cure 7000 (manufactured by T & K TOKA), and the like. These imidazole type hardening accelerators may be used independently and may use 2 or more types together.

The compounding quantity of the said hardening accelerator is not specifically limited, A preferable minimum is 1 weight part with respect to 100 weight part of said curable compounds, and a preferable upper limit is 10 weight part.

When an epoxy resin is used as the curable compound and the curing agent and the curing accelerator are used in combination, the blending amount of the curing agent used is equivalent to the theoretically required equivalent to the epoxy group in the epoxy resin to be used. The following is preferable. If the blending amount of the curing agent exceeds the theoretically required equivalent, chlorine ions may be easily eluted by moisture from a cured product obtained by curing the bonding material. That is, when the curing agent is excessive, for example, when the elution component is extracted with hot water from the cured product of the obtained bonding material, the pH of the extracted water becomes about 4 to 5, so that chloride ions are generated from the epoxy resin. May elute in large quantities. Therefore, it is preferable that the pH of pure water after 1 g of the cured product of the obtained bonding material is immersed in 10 g of pure water at 100 ° C. for 2 hours is 6 to 8, and the pH is 6.5 to 7.5. It is more preferable.

The bonding material may contain a diluent in order to reduce the viscosity.
The diluent preferably has an epoxy group, and the preferable lower limit of the number of epoxy groups in one molecule is 2, and the preferable upper limit is 4. If the number of epoxy groups in one molecule is less than 2, sufficient heat resistance may not be exhibited after the bonding material is cured. If the number of epoxy groups in one molecule exceeds 4, distortion due to curing may occur, or uncured epoxy groups may remain, which may result in poor bonding strength or poor bonding due to repeated thermal stress. May occur. A more preferable upper limit of the number of epoxy groups in one molecule of the diluent is 3.
The diluent preferably has an aromatic ring and / or a dicyclopentadiene structure.

The preferable upper limit of the weight loss at 120 ° C. and the weight loss at 150 ° C. is 1%. If the weight loss at 120 ° C. and the weight loss at 150 ° C. exceed 1%, the unreacted material volatilizes during or after the bonding material is cured, which adversely affects productivity or performance of the semiconductor device. Sometimes.
The diluent preferably has a lower curing start temperature and a higher curing rate than other curable compounds.

The preferable lower limit of the blending amount of the diluent in the bonding material is 1% by weight, and the preferable upper limit is 20% by weight. If the blending amount of the diluent is out of the above range, the viscosity of the bonding material may not be sufficiently reduced.

It is preferable that the bonding material further contains a thixotropic agent. By containing the thixotropic agent, the bonding material can achieve a desired viscosity behavior.
The thixotropy imparting agent is not particularly limited, and examples thereof include fine metal particles, calcium carbonate, fumed silica, inorganic fine particles such as aluminum oxide, boron nitride, aluminum nitride, and aluminum borate. Of these, fumed silica is preferable. Moreover, as the thixotropy-imparting agent, a thixotropy-imparting agent subjected to surface treatment can be used as necessary. In particular, it is preferable to use particles having a hydrophilic group on the surface as the thixotropic agent. Specific examples of the particles having a hydrophilic group on the surface include fumed silica having a hydrophilic group on the surface.

When a particulate thixotropy imparting agent is used as the thixotropy imparting agent, the preferable upper limit of the average particle diameter is 1 μm. When the average particle diameter of the thixotropy-imparting agent exceeds 1 μm, the bonding material may not exhibit the desired thixotropy.

The blending amount of the thixotropy imparting agent in the bonding material is not particularly limited, but a preferred lower limit is 0.5% by weight and a preferred upper limit is 20% by weight. If the blending amount of the thixotropy-imparting agent is less than 0.5% by weight, sufficient thixotropy may not be imparted to the bonding material. If the amount of the thixotropy-imparting agent exceeds 20% by weight, the exclusion property of the bonding material may be lowered. A more preferable lower limit of the amount of the thixotropy-imparting agent is 3% by weight, and a more preferable upper limit is 10% by weight.

The bonding material preferably further contains a polymer compound having a functional group capable of reacting with the curable compound. By including such a polymer compound, the bonding reliability when heat distortion occurs is improved.

In the case of using an epoxy resin as the curable compound as a polymer compound having a functional group capable of reacting with the curable compound, for example, an amino group, a urethane group, an imide group, a hydroxyl group, a carboxyl group, an epoxy group, etc. For example, a polymer compound. Among these, a polymer compound having an epoxy group is preferable. By adding the polymer compound having an epoxy group, the cured product of the bonding material exhibits excellent flexibility. That is, the cured product of the bonding material has excellent mechanical strength, heat resistance and moisture resistance derived from the epoxy resin as the curable compound, and excellent flexibility derived from the polymer compound having the epoxy group. Therefore, the heat cycle resistance, solder reflow resistance, dimensional stability and the like are excellent, and high bonding reliability or high conduction reliability is exhibited.

The polymer compound having an epoxy group is not particularly limited as long as it is a polymer compound having an epoxy group at the terminal and / or side chain (pendant position). For example, an epoxy group-containing acrylic rubber, an epoxy group-containing butadiene rubber, Examples thereof include bisphenol type high molecular weight epoxy resin, epoxy group-containing phenoxy resin, epoxy group-containing acrylic resin, epoxy group-containing urethane resin, and epoxy group-containing polyester resin. Among these, an epoxy group-containing acrylic resin is preferable because a polymer compound containing a large amount of epoxy groups can be obtained, and the cured product has better mechanical strength or heat resistance. These polymer compounds having an epoxy group may be used alone or in combination of two or more.

As the polymer compound having a functional group capable of reacting with the curable compound, the polymer compound having the epoxy group, particularly when the epoxy group-containing acrylic resin is used, the weight average molecular weight of the polymer compound having the epoxy group is A preferred lower limit is 10,000. When the weight average molecular weight is less than 10,000, the film forming property of the bonding material becomes insufficient, and the flexibility of the cured product of the bonding material may not be sufficiently improved.

As the polymer compound having a functional group capable of reacting with the curable compound, a polymer compound having the epoxy group, particularly when an epoxy group-containing acrylic resin is used, the epoxy equivalent of the polymer compound having the epoxy group is preferable. The lower limit is 200, and the preferable upper limit is 1000. When the epoxy equivalent is less than 200, the flexibility of the cured product of the bonding material may not be sufficiently improved. When the epoxy equivalent exceeds 1000, the mechanical strength or heat resistance of the cured product of the bonding material may be insufficient.

Although the compounding quantity of the high molecular compound which has a functional group which can react with the said curable compound is not specifically limited, A preferable minimum is 1 weight part and a preferable upper limit is 150 weight part with respect to 100 weight part of said curable compounds. When the blending amount of the polymer compound having a functional group capable of reacting with the curable compound is less than 1 part by weight, the bonding material may not have sufficient reliability against thermal strain. When the blending amount of the polymer compound having a functional group capable of reacting with the curable compound exceeds 150 parts by weight, the heat resistance of the bonding material may be lowered.

It is preferable that the bonding material further contains a surface-treated silica filler. Although the said surface-treated silica filler is not specifically limited, The silica filler surface-treated with the phenylsilane coupling agent is preferable.

The amount of the surface-treated silica filler is not particularly limited, but a preferable lower limit is 30 parts by weight and a preferable upper limit is 400 parts by weight with respect to 100 parts by weight of the curable compound. When the blending amount of the surface-treated silica filler is less than 30 parts by weight, the bonding material may not be able to maintain sufficient reliability. When the compounding amount of the surface-treated silica filler exceeds 400 parts by weight, the viscosity of the bonding material becomes too high, and the coating stability may be lowered.

The bonding material may contain a solvent as necessary.
The solvent is not particularly limited, and examples thereof include aromatic hydrocarbons, chlorinated aromatic hydrocarbons, chlorinated aliphatic hydrocarbons, alcohols, esters, ethers, ketones, glycol ethers (cellosolves), and fats. Examples thereof include cyclic hydrocarbons and aliphatic hydrocarbons.

The said joining material may contain an inorganic ion exchanger as needed.
Among the inorganic ion exchangers, examples of commercially available products include IXE series (manufactured by Toagosei Co., Ltd.). A preferable upper limit of the amount of the inorganic ion exchanger in the bonding material is 10% by weight, and a preferable lower limit is 1% by weight.

The bonding material may contain other additives such as an adhesion promoter such as a bleed inhibitor and an imidazole silane coupling agent, if necessary.

In the bonding material, the preferable lower limit of the minimum melt viscosity in the temperature range from room temperature to the solder melting point is 0.1 Pa · s, and the preferable upper limit is 10 ⁴ Pa · s. If the minimum melt viscosity is less than 0.1 Pa · s, the fillet may protrude too much and contaminate other devices. If the minimum melt viscosity exceeds 10 ⁴ Pa · s, the void may not be sufficiently removed.
The minimum melt viscosity in the temperature range from room temperature to the solder melting point can be measured using a rheometer.

The method for producing the bonding material is not particularly limited, for example, a curable compound and a curing agent, if necessary, a curing accelerator, a polymer compound having a functional group capable of reacting with the curable compound, a thixotropic agent, A method of producing a paste-like bonding material by mixing a predetermined amount of other additives and the like, and applying the resin composition obtained by mixing in the same manner on a release film, followed by drying, Examples thereof include a method for producing a sheet-like bonding material. The mixing method is not particularly limited, and examples thereof include a method using a homodisper, a universal mixer, a Banbury mixer, a kneader and the like.

In the method for manufacturing a semiconductor device of the present invention, the temperature is then heated to a temperature equal to or higher than the solder melting point so that the curing rate of the bonding material is 40% or less, and the protruding electrode of the semiconductor chip and the electrode portion of the substrate are melted. An electrode joining step for joining is performed.
By performing such an electrode bonding step, and then performing a void removing step of removing the void by heating the bonding material having a curing rate of 40% or less in a pressurized atmosphere, air is temporarily involved in the bonding material. Even in this case, voids can be removed and electrode bonding can be performed satisfactorily. Such an electrode bonding step is also generally performed using a mounting apparatus such as a flip chip bonder.

In the electrode bonding step, for example, using a mounting device such as a flip chip bonder, the protruding electrode of the semiconductor chip and the electrode portion of the substrate are brought into contact, and then the temperature is raised to the solder melting point or higher to To melt. In this case, as a method of setting the curing rate of the bonding material to 40% or less while performing electrode bonding satisfactorily, for example, the temperature at which the protruding electrode of the semiconductor chip and the electrode portion of the substrate are brought into contact with each other, or the temperature at which the solder is melted It is preferable to control the total time (mounting time) for performing contact and melting of the solder.

The preferable lower limit of the contact temperature is 120 ° C., and the preferable upper limit is 210 ° C. When the contact temperature is less than 120 ° C., the fluidity of the bonding material becomes insufficient, and the fillet is not formed well, and the reliability may be lowered. When the contact temperature exceeds 210 ° C., the solder is in a molten state at the time of contact, and there is a case where the contact is not good due to the bonding material in which the protruding electrode of the semiconductor chip and the electrode portion of the substrate are interposed.
Since the solder melting point is usually about 225 to 235 ° C., the preferable lower limit of the temperature for melting the solder is 240 ° C., and the preferable upper limit is 280 ° C.
The preferable lower limit of the mounting time is 1 second, and the preferable upper limit is 10 seconds. If the mounting time is less than 1 second, the temperature cannot be raised above the solder melting point, and proper electrode bonding may not be obtained. When the mounting time exceeds 10 seconds, the curing rate of the bonding material may exceed 40%.

If the curing rate of the bonding material exceeds 40%, voids cannot be sufficiently removed when air is entrained in the bonding material. The curing rate of the bonding material is preferably 30% or less, and more preferably 20% or less. Moreover, the minimum of the hardening rate of the said joining material is not specifically limited.
In addition, the hardening rate (%) of a joining material means the value calculated | required by following formula (1).
Curing rate of bonding material (%) = (1−Dh / Di) × 100 (1)
In formula (1), Di represents the heating value in the initial state of the bonding material calculated by the differential scanning calorimeter, and Dh represents the heating value after the heat treatment of the bonding material calculated by the differential scanning calorimeter. .

In the method for manufacturing a semiconductor device of the present invention, a void removing step is then performed in which the bonding material having a curing rate of 40% or less is heated in a pressurized atmosphere to remove voids.
Under a pressurized atmosphere means a pressure atmosphere higher than normal pressure (atmospheric pressure). By performing the void removing step, the void can be removed even when air is caught in the bonding material. Here, it is considered that the voids can be positively removed rather than merely growing. In the void removal step, the bonding material is also cured, but the bonding material may be completely cured when removing the void, or the bonding material is cured to an intermediate stage when removing the void, A two-stage temperature profile that raises the temperature to completely cure the bonding material may be performed. In addition, a curing step for completely curing the bonding material may be performed separately. In particular, it is preferable to perform a two-stage temperature profile in the void removal process.

Examples of a method for heating the above-mentioned bonding material having a curing rate of 40% or less in a pressurized atmosphere include a method using a pressure curing oven (for example, PCO-083TA manufactured by NTT Atvans Technology).
At this time, the preferable lower limit of the pressure is 0.1 MPa, and the preferable upper limit is 10 MPa. If the pressure is less than 0.1 MPa, voids may not be sufficiently removed when air is entrained in the bonding material. When the pressure exceeds 10 MPa, the bonding material itself is deformed, which may adversely affect the reliability of the semiconductor device. The more preferable lower limit of the pressure is 0.3 MPa, and the more preferable upper limit is 1 MPa.

Further, the heating temperature when heating the above-mentioned bonding material having a curing rate of 40% or less in a pressurized atmosphere is preferably set with reference to the minimum melt viscosity of the bonding material. It is preferably within the range of ± 20 ° C. of the temperature showing the melt viscosity.

In the method for manufacturing a semiconductor device of the present invention, a mounting device such as a flip chip bonder incorporated in a pressurized container is used, and the process from the alignment step to the void removing step is performed in a pressurized atmosphere as a continuous step. You may go on. In this case, it is not necessary to use another device or transport to another device in order to create a pressurized atmosphere, and it is possible to reduce the adjustment of pressure, thereby reducing the production efficiency. Absent.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the semiconductor device which can suppress a void and can implement | achieve high reliability can be provided.

Examples of the present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.
In addition, the particle size measuring machine (Coulter counter ZB / C-1000, the product made by Coulter Electronics) was used for the measurement of the particle diameter as described in the following Examples and Comparative Examples.

Example 1
(1) Manufacture of bonding material paste According to the composition described in Table 1, a bonding material paste was manufactured by stirring and mixing the materials shown below using a homodisper. When the minimum melt viscosity of the obtained bonding material paste was measured with a rheometer, it was 1 Pa · s at 150 ° C.
1. Epoxy resin bisphenol F type epoxy resin (EXA-830-CRP, manufactured by DIC Corporation)
2. Epoxy group-containing high molecular compound epoxy group-containing acrylic resin (Blenmer CP-30, manufactured by NOF Corporation)
3. Rubber-modified epoxy resin NBR-modified epoxy resin (EPR-4033, manufactured by Adeka)
4). Hardener acid anhydride (YH-306, manufactured by Mitsubishi Chemical Corporation)
5. Curing accelerator imidazole compound (2MA-OK, manufactured by Shikoku Chemicals)
6). Adhesion imparting agent imidazole silane coupling agent (SP-1000, manufactured by Nikko Materials)
7). Thixotropy imparting agent fumed silica (surface hydrophilic group-containing thixotropy imparting agent, QS-40, manufactured by Tokuyama Corporation)
8). Silica filler spherical silica (SE-4050-SPE, manufactured by Admatechs, average particle size 1 μm, maximum particle size 5 μm)

(2) Manufacture of semiconductor device (2-1) Positioning step and electrode bonding step The obtained bonding material paste is filled into a 10 mL syringe (manufactured by Iwashita Engineering Co., Ltd.), and a precision nozzle (manufactured by Iwashita Engineering Co., Ltd., nozzle) at the syringe tip A tip diameter of 0.3 mm was attached, and a dispenser device (SHOT MASTER300, manufactured by Musashi Engineering Co., Ltd.) was used to apply on the substrate at a discharge pressure of 0.4 MPa, a gap between the substrate and the needle of 200 μm, and an application amount of 1.5 mg. . Using a flip chip bonder (FC-3000S, manufactured by Toray Engineering Co., Ltd.), a semiconductor chip (a protruding electrode having a tip portion made of solder is formed on the surface via the applied bonding material paste, thickness 100 μm, WALTS -TEG MB50-0101JY (manufactured by Waltz) is aligned on the substrate and mounted at 170 ° C., 20N for 2 seconds, 250 ° C., 20N for 2 seconds, stage temperature 70 ° C. The electrode and the electrode part of the substrate were melt-bonded to obtain a mounting body.
At this time, the curing rate of the bonding material paste was 15%. Note that the curing rate (%) of the bonding material paste was prepared by separately preparing a sample for measuring the curing rate under the same conditions, peeling off the semiconductor chip from the obtained sample, scraping a part of the bonding material paste, and DSC 6220 It calculated | required by Formula (1) from the emitted-heat amount measured at the temperature increase of 10 degree-C / min by Seiko Instruments (made by Seiko Instruments).

(2-2) Void Removal Step About the obtained mounting body, void removal was performed under the following pressure and heating conditions using a pressure curing oven (PCO-083TA NTT Advanced Technology) to obtain a semiconductor device. .
<Pressurization and heating conditions>
STEP1: Hold at 40 ° C for 5 minutes, 0.5 MPa
STEP 2: Constant temperature rise to 150 ° C in 30 minutes, 0.5 MPa
STEP3: Hold at 150 ° C. for 30 minutes, 0.5 MPa
STEP 4: Constant heating up to 170 ° C in 10 minutes, 0.5 MPa
STEP5: Hold at 170 ° C. for 30 minutes, 0.5 MPa
STEP6: Constant temperature drop to room temperature in 60 minutes, 0.5 MPa

(Example 2)
The conditions at the time of melt-bonding the protruding electrode of the semiconductor chip and the electrode portion of the substrate using a flip chip bonder are changed to 170 ° C., 20N for 4 seconds load, 250 ° C., 20N for 3 second load, and bonding at this time A semiconductor device was obtained in the same manner as in Example 1 except that the curing rate of the material paste was 35%.

(Comparative Example 1)
The conditions at the time of melt-bonding the protruding electrode of the semiconductor chip and the electrode part of the substrate using a flip chip bonder were changed to 170 ° C., 20N for 8 seconds load, 250 ° C., 20N for 3 second load, and bonding at this time A semiconductor device was obtained in the same manner as in Example 1 except that the curing rate of the material paste was 45%.

(Evaluation)
The following evaluations were performed on the semiconductor devices obtained in Examples 1 and 2 and Comparative Example 1. The results are shown in Table 1.

(1) Presence / absence of voids Using an ultrasonic exploration imaging apparatus (C-SAM D9500, manufactured by Nihon Burns), the voids of the mounting body before and after the void removal process were observed and evaluated according to the following criteria.
○ Little void was observed.
Δ: Slight voids were observed.
X Conspicuous peeling due to voids was observed.

(2) Connection reliability The connection reliability was evaluated by performing a temperature cycle test on 10 obtained semiconductor devices. In the temperature cycle test, precondition conditions were set to JEDEC LEVEL3 test condition B, and the conditions were −55 ° C. to 125 ° C. and 1000 cycles. The resistance after the test was conducted within ± 5% of the initial value, and the non-defective product rate was evaluated by obtaining the non-defective product rate among 10 samples.

(Example 3)
(1) Production of Bonding Material Sheet According to the composition shown in Table 2, the following materials were stirred and mixed using a homodisper to prepare a resin composition. On the release PET film (thickness 50 μm), the resulting resin composition was applied by a comma coating method so that the thickness of the resin layer after drying was 30 μm, and dried at 100 ° C. for 5 minutes to form a resin layer Formed. Next, another release PET film (thickness 25 μm) was bonded to the obtained resin layer with a laminator to obtain a bonding material sheet. When the minimum melt viscosity of the obtained bonding material sheet was measured with a rheometer, it was 300 Pa · s at 160 ° C.
1. Epoxy resin dicyclopentadiene type epoxy resin (HP-7200HH, manufactured by DIC)
Dicyclopentadiene type epoxy resin (EP4088L, manufactured by Adeka)
2. Epoxy group-containing acrylic resin Glycidyl group-containing acrylic resin (G-2050-M, weight average molecular weight 200,000, manufactured by NOF Corporation)
Glycidyl group-containing acrylic resin (G-0250SP, weight average molecular weight 10,000, manufactured by NOF Corporation)
3. Hardener acid anhydride (YH-309, manufactured by Mitsubishi Chemical Corporation)
4). Curing accelerator Liquid imidazole compound at normal temperature (Fujicure 7000, manufactured by T & K TOKA)
5. Silica filler phenyltrimethoxysilane surface-treated spherical silica (SX009-MJF, manufactured by Admatechs, average particle size 0.05 μm)

(2) Manufacturing of semiconductor device (2-1) Positioning step and electrode bonding step The release PET film (thickness 25 μm) of the obtained bonding material sheet is peeled off, and a vacuum laminator (ATM-812M manufactured by Takatori Co., Ltd.) is used. Then, the bonding material sheet was bonded to a semiconductor chip (80 μm thick, WALTS-TEG MB50-0101JY, manufactured by Waltz Co., Ltd. having a protruding electrode having a tip made of solder formed on the surface) at 80 ° C. and 80 Pa. . The release PET film (thickness 50 μm) of the bonding material sheet is peeled off, and the semiconductor chip is aligned on the substrate via the bonding material sheet using a flip chip bonder (FC-3000S, manufactured by Toray Engineering Co., Ltd.). By mounting at a temperature of 40 ° C. for 2 seconds, loading at 250 ° C. and 20N for 1 second, and a stage temperature of 120 ° C., the protruding electrode of the semiconductor chip and the electrode portion of the substrate were melt-bonded to obtain a mounting body.
At this time, the curing rate of the bonding material sheet was 10%. The curing rate (%) of the bonding material sheet was determined in the same manner as in Example 1.

(2-2) Void removal process About the obtained mounting body, it carried out similarly to Example 1, and obtained the semiconductor device.

Example 4
The conditions at the time of melt-bonding the protruding electrode of the semiconductor chip and the electrode portion of the substrate using a flip chip bonder were changed to 150 ° C., 20N for 5 seconds load, 250 ° C., 40N for 3 second load, and bonding at this time A semiconductor device was obtained in the same manner as in Example 3 except that the curing rate of the material sheet was 35%.

(Comparative Example 2)
The conditions at the time of melt-bonding the protruding electrode of the semiconductor chip and the electrode portion of the substrate using a flip chip bonder are changed to 150 ° C., 40N for 8 seconds load, 250 ° C., 20N for 4 seconds load, and bonding at this time A semiconductor device was obtained in the same manner as in Example 3 except that the curing rate of the material sheet was 50%.

(Evaluation)
The semiconductor devices obtained in Examples 3 and 4 and Comparative Example 2 were evaluated in the same manner as in Examples 1 and 2 and Comparative Example 1. The results are shown in Table 2.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the semiconductor device which can suppress a void and can implement | achieve high reliability can be provided.

Claims (2)

An alignment step of aligning a semiconductor chip on which a protruding electrode having a tip made of solder is formed on a substrate via a bonding material;
The protruding electrode of the semiconductor chip and the electrode portion of the substrate are brought into contact with each other at a temperature of 120 ° C. or higher and 210 ° C. or lower, and then heated to a temperature of the solder melting point or higher, whereby the curing rate of the bonding material is 30% or lower And an electrode bonding step of melt bonding the protruding electrode of the semiconductor chip and the electrode portion of the substrate,
Void removal for removing voids by heating the bonding material having a curing rate of 30% or less in a pressure range of 0.1 MPa or more and 10 MPa or less in a range of ± 20 ° C. at which the bonding material exhibits a minimum melt viscosity. And a method of manufacturing a semiconductor device. The method for manufacturing a semiconductor device according to claim 1, wherein the bonding material has a minimum melt viscosity of 10 ⁴ Pa · s or less in a temperature range from room temperature to a solder melting point.