JP2005093788A - Semiconductor device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor device exhibiting satisfactory connection reliability by using a thermosetting adhesive film and conducting flip chip connection by metal bonding by the use of supersonic vibration, and to provide a manufacturing method for obtaining high productivity. <P>SOLUTION: The method for manufacturing the semiconductor device comprises steps of (a) preparing a semiconductor chip having a projecting connection terminal, a substrate on which a wiring pattern is formed, and a thermosetting adhesive film; (b) forming an adhesive resin layer by applying the thermosetting adhesive film on the surface of the substrate; (c) electrically connecting the projecting connection terminal of the semiconductor chip and the wiring pattern on the surface of the substrate, and adhering the semiconductor chip and the substrate by the adhering resin layer by applying the supersonic vibration in a heated/pressurized condition after positioning the projecting connection terminal of the semiconductor chip and the wiring pattern on the surface of the substrate; (d) and applying heat treatment to make a curing reaction rate of the adhesive resin layer not less than 80%. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a semiconductor device and a manufacturing method thereof.

  With the recent progress of miniaturization and high functionality of electronic devices, development of semiconductor chip mounting technology corresponding to thinning and high-speed transmission is required. Among them, as a form of electrically connecting the semiconductor chip having protruding connection terminals (bumps) and the substrate, the surface on which the bumps of the semiconductor chip are formed and the surface on which the wiring pattern of the substrate is formed are opposed to each other. Thus, flip-chip connection technology that directly connects bumps and wiring patterns has attracted attention.

As a flip chip connection technique, a semiconductor chip is formed by using a C4 method (for example, see Non-Patent Document 1) for electrically connecting a solder bump formed on a semiconductor chip and a wiring pattern on the substrate side, and using an anisotropic conductive adhesive resin. A method of electrically connecting bumps formed on the substrate and the wiring pattern on the substrate side via conductive particles (see, for example, Non-Patent Document 2), a state in which the bump formed on the semiconductor chip and the wiring pattern on the substrate side are in contact with each other A method is known in which a thermosetting adhesive resin is cured and the contact state is maintained by its contraction force (for example, Non-Patent Document 3).
Japanese Patent Laid-Open No. 08-330880 JP 2000-178522 A Hideo Aoki, and four others, "Eutectic Solder Flip Chip Technology-Bumping and Assembly Process Development for CSP / BGA", 47th Electronic Component and Technology Conference, the United States, Institute of Electrical and Electronics Engineers, 5 May 1997, p. 325-330 Shinichi Fujiwara and 4 others, “Degradation mechanism of flip chip connection using anisotropic conductive film and connection reliability design technology”, 7th Symposium on Microjoining and Assembly Technology in Electronics, Japan Welding Society Microjoining Research Committee, February 2001, p. 179-184 Hidenobu Nishikawa, 4 others, “Flip Chip Joining Technology Using Resin Encapsulated Sheet”, 6th Symposium on Microjoining and Assembly Technology in Electronics, Japan Welding Society Microjoining Research Committee, February 2000, p. 107-110 Ryoichi Sugawara, 5 others, “Ultrasonic flip chip bonding technology for multi-pin LSI chips”, 7th Symposium on Microjoining and Assembly Technology in Electronics, Japan Welding Society Microjoining Research Committee, February 2001, p. 161-166

  In the C4 system, the use of solder that does not contain lead has been studied from the viewpoint of lead-free soldering. However, as the reflow temperature increases, the thermal stress increases and the connection reliability may decrease. In order to ensure, it is necessary to use a substrate material having high heat resistance. Also, in order to achieve high connection reliability, an underfill process that fills and hardens the liquid resin between the semiconductor chip and the substrate is required, but it takes a long time to fill the narrow gap, and productivity Decreases.

  In the connection method using anisotropic conductive adhesive resin and the method of maintaining the contact state by the shrinkage force of the thermosetting adhesive resin, it takes 10 to 20 seconds to cure the adhesive resin, and the viewpoint of improving the productivity Therefore, shortening of connection time is required. In addition, since the bump and the wiring pattern are electrically connected by mechanical contact, the adhesive force between the adhesive resin and the semiconductor chip surface is reduced, or the contact portion is caused by the thermal expansion of the adhesive resin when left at high temperature. As a result of generating a force that separates the contact resistance, the connection resistance may increase or conduction failure may occur.

  On the other hand, recently, a flip chip connection method using metal bonding using ultrasonic vibration has attracted attention (for example, see Non-Patent Document 4). The features of this method are 1) that bumps and wiring patterns can be metal-bonded at low temperatures (room temperature to 200 ° C), and 2) the time required for connection is 1 second or less, and heat There is a possibility of realizing high connection reliability by reducing stress and forming a metal joint, and high productivity by short-time connection. There has been an example in which a small chip such as a SAW (Surface Acoustic Wave) filter has been flip-chip connected to a ceramic substrate (for example, Japanese Patent Laid-Open No. 08-330880). It was limited to the case where the underfill process of filling with was unnecessary. However, when flip chip connection is used to connect a larger chip and a resin substrate using ultrasonic vibration, an underfill process is indispensable to ensure reliability, and it takes a long time to fill a narrow gap with liquid resin. Therefore, there is a possibility that productivity may be reduced.

  Therefore, the present invention provides a semiconductor device exhibiting good connection reliability and a manufacturing method for realizing high productivity by performing flip chip connection by metal bonding using ultrasonic vibration using a thermosetting adhesive film. The purpose is to do.

The present invention is characterized by the following.
(1) In the method for manufacturing a semiconductor device, (a) a step of preparing a semiconductor chip having protruding connection terminals, a substrate on which a wiring pattern is formed, and a thermosetting adhesive film, (b) a thermosetting adhesion to the substrate surface. A step of forming an adhesive resin layer by attaching a film; (c) by aligning the protruding connection terminals of the semiconductor chip and the wiring pattern on the substrate surface, and then applying ultrasonic vibration in a heated and pressurized state. A step of electrically connecting the protruding connection terminal of the semiconductor chip and the wiring pattern on the surface of the substrate and bonding the semiconductor chip and the substrate with an adhesive resin layer; and (d) setting the curing reaction rate of the adhesive resin layer to 80% or more. A method for manufacturing a semiconductor device, comprising a step of performing a heat treatment.
(2) In the method of manufacturing a semiconductor device, (a) a step of preparing a semiconductor chip having a protruding connection terminal, a substrate on which a wiring pattern is formed, and a thermosetting adhesive film, (b) a protruding connection terminal of the semiconductor chip A process of forming an adhesive resin layer by attaching a thermosetting adhesive film to the surface having a surface, (c) after aligning the protruding connection terminals of the semiconductor chip and the wiring pattern of the substrate surface, in a heated and pressurized state A step of electrically connecting the protruding connection terminal of the semiconductor chip and the wiring pattern on the substrate surface by applying ultrasonic vibration and bonding the semiconductor chip and the substrate with an adhesive resin layer; (d) curing of the adhesive resin layer; A method for manufacturing a semiconductor device, comprising a step of performing a heat treatment to increase a reaction rate to 80% or more.
(3) The method of manufacturing a semiconductor device according to (2), further comprising a step of dividing the semiconductor device into individual semiconductor chips after the step (b).
(4) The method for manufacturing a semiconductor device includes a step of heat-treating the substrate on which the adhesive resin layer is formed or the semiconductor chip on which the adhesive resin layer is formed before the step (c) ( A method for manufacturing a semiconductor device according to any one of 1) to (3).
(5) In the method of manufacturing a semiconductor device, the heat treatment in the step (d) is a heat treatment of at least two stages or more, wherein the method of manufacturing a semiconductor device according to any one of (1) to (4) .
(6) In the method for manufacturing a semiconductor device, the thermosetting adhesive film is a thermosetting adhesive film having a viscosity of 4000 Pa · s or less at any temperature of 50 to 250 ° C. (1) to (5) A method for manufacturing the semiconductor device according to claim 1.
(7) A semiconductor device manufactured by the method for manufacturing a semiconductor device according to any one of (1) to (6).

  According to the present invention, it is possible to connect a chip and a substrate in a short time of 1 second or less through a thermosetting adhesive film using metal bonding by ultrasonic vibration, and a liquid resin is provided in the gap between the chip and the substrate. It is possible to omit the underfill process for filling the semiconductor device, and to provide a semiconductor device that realizes high connection reliability and a method for manufacturing a semiconductor device that realizes high productivity.

  In the substrate of the step (a), the substrate electrically connected to the semiconductor chip having the protruding connection terminal may be a normal circuit substrate or a semiconductor chip. In the case of a circuit board, the wiring pattern can also be formed by etching away unnecessary portions of a metal layer such as copper formed on the surface of an insulating substrate such as glass epoxy, polyimide, or ceramic. It can also be formed. Moreover, the wiring pattern does not need to be composed of a single metal, and may contain a plurality of metal components such as gold, silver, copper, nickel, indium, palladium, tin, lead, and bismuth. You may have the structure where the metal layer was laminated | stacked. When the substrate is a semiconductor chip, the wiring pattern is usually made of aluminum, but a metal layer such as gold, silver, copper, nickel, indium, palladium, tin, lead, or bismuth is formed on the surface by plating. May be.

  In the semiconductor chip having the projecting connection terminal in the step (a), the projecting connection terminal of the semiconductor chip is formed by using a gold stud bump or a metal ball formed by using a gold wire on the electrode of the semiconductor chip by thermocompression bonding or ultrasonic wave. Those fixed by thermocompression bonding and those formed by plating or vapor deposition may be used. The protruding connection terminal does not need to be made of a single metal, and may contain a plurality of metal components such as gold, silver, copper, nickel, indium, palladium, tin, lead, and bismuth. You may have the structure where the metal layer was laminated | stacked. Further, the semiconductor chip having the protruding connection terminal may be in the state of a semiconductor wafer having the protruding connection terminal.

  In the thermosetting adhesive film of the step (a), the thermosetting component contained in the thermosetting adhesive film includes an epoxy resin, a bismaleimide triazine resin, a polyimide resin, a cyanoacrylate resin, a phenol resin, and an unsaturated polyester resin. , Melamine resin, urea resin, polyisocyanate resin, furan resin, resorcinol resin, xylene resin, benzoguanamine resin, diallyl phthalate resin, siloxane modified epoxy resin, siloxane modified polyamideimide resin, benzocyclobutene resin, or unvulcanized (uncrosslinked) Natural rubber, nitrile rubber, butadiene rubber, silicone rubber, isobutylene rubber and the like can be used. These resins may be a copolymer system or a mixed system.

  In addition, thermosetting adhesive films are phenolic, imidazole, hydrazide, boron trifluoride-amine complexes, sulfonium salts, amine imides, polyamine salts, dicyandiamide and other hardeners that react with the thermosetting components. A coupling agent that increases the strength, an inorganic filler such as silica or a metal oxide, and a thermoplastic resin such as a phenoxy resin may be included in order to make film formation easier.

  The viscosity of the thermosetting adhesive film is preferably 4000 Pa · s or less at any temperature of 50 to 250 ° C. If it exceeds 4000 Pa · s, the resin is present between the protruding connection terminal of the semiconductor chip and the wiring pattern. It may remain and cause poor connection. More preferably, it is 3000 Pa · s or less, and particularly preferably 1000 Pa · s or less.

  The viscosity can be measured using a commercially available dynamic viscoelasticity measuring apparatus, and the measurement is performed fully automatically. When a sample is sandwiched between two parallel plates in a thermostatic chamber heated to a predetermined temperature, and a minute sinusoidal twist distortion is applied to one plate, the elastic modulus and strain are determined from the stress and strain generated on the other plate. Viscosity is calculated. Generally, the measurement frequency is 0.5 to 10 Hz, and the polymer material behaves as a viscoelastic body, so that a storage elastic modulus derived from an elastic component and a loss elastic modulus derived from a viscous component are obtained. When the viscosity is η (Pa · s), the measurement frequency is f (Hz), and the loss elastic modulus G ″ (Pa), the viscosity is given by the general formula (I).

  In step (b), in order to apply the thermosetting adhesive film to the area where the semiconductor chip on the substrate surface is mounted, place the adhesive film cut into individual pieces in the application area and apply it by heating and pressing. May be. The position and area for attaching the adhesive film is arbitrary within the area where the semiconductor chip is mounted, but it is attached so as to cover at least part of the wiring pattern electrically connected to the protruding connection terminal of the semiconductor chip. Is preferred.

  In the step (b), in order to affix the thermosetting adhesive film to the semiconductor chip having the protruding connection terminals, the adhesive film cut into pieces may be affixed by heating and pressing. Also, after sticking the thermosetting adhesive film with a roll laminator or the like in the state of a semiconductor wafer having protruding connection terminals (step (b)), the adhesive film is adhered by dicing, and the protruding connection terminals are The semiconductor chip may be cut into individual pieces.

  After the thermosetting adhesive film is attached to the semiconductor chip on the surface of the substrate where the semiconductor chip is mounted or the protruding connection terminal, the semiconductor chip and the substrate may be connected as they are. In order to reduce the components and suppress the generation of bubbles called voids between the semiconductor chip and the substrate, it is preferable to perform heat treatment with an adhesive film attached before step (c).

  In addition, when a thermosetting adhesive film is attached in the state of a semiconductor wafer having protruding connection terminals, it may be heat-treated after being cut into pieces as a semiconductor chip to which the thermosetting adhesive film is attached, Heat treatment may be performed before cutting into individual pieces. Moreover, since the viscosity of a thermosetting adhesive film falls by heat-processing before a process (c), the embedding property to a wiring pattern is improved and the void generation | occurrence | production by bubble entrainment can be reduced.

  When performing the heat treatment before the step (c), it is desirable to perform the treatment at a temperature lower than the curing reaction start temperature of the thermosetting adhesive film to be used or shorter than the reaction start time. The curing reaction start temperature may be obtained from the intersection of the tangent line and the baseline of the exothermic curve before reaching the exothermic peak in the chart obtained by DSC (Differential Scanning Calorimeter), or the viscosity and the heating temperature. The temperature at which the viscosity starts to rise may be obtained by plotting the above relationship. The curing reaction start time may be obtained by plotting the relationship between the processing time of the sample heat-treated at a predetermined temperature and the calorific value obtained by DSC, and obtaining the time until the calorific value starts decreasing, or the viscosity and processing The time until the viscosity starts to rise may be obtained by plotting the time relationship.

  In the step (c), in order to electrically connect the semiconductor chip and the substrate, the substrate is fixed to the stage, the semiconductor chip is fixed to the bonding head attached in parallel to the ultrasonic vibration direction, and the bonding head is pressed from above. A device having a mechanism is used. Such devices are commercially available.

  When applying ultrasonic vibration in a heated and pressurized state, the conditions for connecting the semiconductor chip and the substrate are as follows: connection temperature: 50-250 ° C., pressure: 0.1-10 MPa, ultrasonic frequency: 20- 200 kHz, amplitude of vibration: 0.01 μm or more, pressurization time: 0.1 second or more, application time of ultrasonic wave: 0.05 second or more, and the timing of pressurization and ultrasonic application exceeds the pressurization time. Application of the sound wave may be performed at an arbitrary timing as long as the application of the sound wave is satisfied and the application of the ultrasonic wave is completed within the pressurization time. Thereby, it is possible to electrically connect the protruding connection terminal of the semiconductor chip and the wiring pattern on the surface of the substrate by metal bonding, and bond the semiconductor chip and the substrate with the adhesive resin layer.

  If the connection temperature is less than 50 ° C., the adhesive resin remains between the bump and the wiring pattern, and there is a possibility that the connection is not connected or the connection resistance is increased. When the connection temperature exceeds 250 ° C., the thermal stress derived from the difference in thermal expansion coefficient between the semiconductor chip and the substrate increases, and the connection portion may be damaged. In the case of a resin substrate, if the temperature exceeds 250 ° C., the substrate is softened and ultrasonic vibrations are absorbed, which may prevent metal bonding. More preferably, it is the range of 50-200 degreeC.

  If the pressure is less than 0.1 MPa, the resin may remain between the connecting terminals facing each other, which may result in disconnection or increase in connection resistance. If the pressure exceeds 10 MPa, the connection terminals and wiring are destroyed. There is a risk of being. More preferably, it is the range of 0.3-4.0 MPa.

  If the frequency of the ultrasonic wave is less than 20 kHz, the connection terminals and wiring may be destroyed. If the frequency exceeds 200 kHz, ultrasonic vibrations are not transmitted to the connection part, and the resin remains between the connection terminals facing each other. However, there is a possibility that the connection resistance becomes high due to the lack of connection or insufficient metal bonding. More preferably, it is the range of 40-100 kHz.

  If the amplitude of the ultrasonic vibration is less than 0.01 μm, the resin remains between the connecting terminals facing each other and is not connected, or the diffusion resistance of the metal is insufficient, resulting in an increase in connection resistance or connection reliability. May decrease. More preferably, it is the range of 0.1-10 micrometers.

  If the pressurization time is less than 0.1 seconds, the resin may remain between the connecting terminals facing each other, may not be connected, or the connection resistance may increase, connection reliability may decrease, When the pressurization time is lengthened, the productivity is lowered. Therefore, the pressurization time is preferably shortened, and is preferably within 10 seconds.

  If the application time of the ultrasonic wave is less than 0.05 seconds, the metal surface is insufficiently removed due to insufficient removal of organic substances and oxides on the metal surface, resulting in insufficient metal bonding, high connection resistance, and low connection reliability. There is a case. Further, when the amplitude is increased or the frequency is decreased, if the application time is lengthened, the connection terminal or the wiring may be destroyed. More preferably, it is within 5 seconds, and if it exceeds 5 seconds, the productivity may be lowered.

  In step (d), after electrically connecting the protruding connection terminals of the semiconductor chip and the wiring pattern on the surface of the substrate, heat treatment is performed so that the curing reaction rate of the adhesive resin layer becomes 80% or more, thereby achieving high connection. Reliability can be ensured. It is more preferable to perform heat treatment so that the curing reaction rate is 90% or more.

  In order to perform the heat treatment so that the curing reaction rate of the adhesive resin layer becomes 80% or more, it may be left on a heat stage or left in a heating oven. This heat treatment step can be performed for a plurality of semiconductor devices at once, and does not lead to a decrease in productivity.

  The heat treatment is preferably performed at a temperature higher than the curing start temperature. However, immediately after connecting the semiconductor chip and the substrate, the curing reaction rate of the adhesive resin layer is less than 80%. Therefore, if the heat treatment is performed from the beginning at a temperature higher than the curing start temperature, the thermal expansion between the semiconductor chip and the substrate will occur. There is a possibility that the thermal stress derived from the coefficient difference is concentrated on the connection portion and damage is generated in the connection portion. Therefore, it is more preferable to start the heating at a temperature lower than the curing start temperature and to perform the treatment at a heating temperature of at least two stages. The curing reaction start temperature can be obtained from DSC as described above.

  For the measurement of the curing reaction rate of the thermosetting resin, a method by DSC (differential scanning thermal analysis) can be used. DSC is based on the zero principle method of supplying or removing the amount of heat so as to cancel out the temperature difference from the standard sample that does not generate heat or endotherm within the measurement temperature range. Measurement can be performed automatically. The reaction of the thermosetting resin is an exothermic reaction, and when the sample is heated at a constant temperature increase rate, the sample reacts to generate reaction heat. The amount of heat generation is output to a chart, and the area of the region surrounded by the heat generation curve and the base line is defined as the amount of heat generation based on the baseline. The measurement is performed in a range that sufficiently covers the temperature at which the curing reaction is completed from room temperature. For example, in the case of an epoxy resin, measurement is performed at a temperature increase rate of 5 to 20 ° C./min from room temperature to 250 ° C., and the above-described calorific value is obtained. The curing reaction rate of the thermosetting resin is determined as follows. First, the total calorific value of the uncured sample is measured, and this is defined as A (J / g). Next, the calorific value of the measurement sample is measured, and this is defined as B. The curing reaction rate C (%) of the measurement sample is given by the general formula (II).

  In addition, when an epoxy resin is used as the thermosetting resin, the peak intensity or area intensity of the Raman spectrum of the epoxy group measured with a visible laser-excited Raman spectrometer or near-infrared laser-excited Raman spectrometer is used. It is also possible to evaluate the reaction hardening rate (for example, JP 2000-178522 A).

(1) Preparation of wiring board A dry film resist is laminated on the surface of the copper layer of the glass epoxy copper clad laminate, a photomask that transmits light is superimposed on the shape of the wiring pattern, and ultraviolet light is applied to develop with a developer. Thus, an etching resist was formed. A glass epoxy substrate is formed by treating with an etching solution containing ferric chloride as a main component, stripping the etching resist, and forming a nickel layer having a thickness of 5 μm and a gold layer having a thickness of 0.05 μm by electroless plating. A wiring board 3 having a wiring pattern 2 formed on the surface of 1 was prepared (see FIG. 1A).
(2) Preparation of semiconductor chip having protruding connection terminals A semiconductor chip was prepared in which gold stud bumps 6 were formed on the aluminum electrodes 5 of the semiconductor chip 4 using gold wires (see FIG. 1B).
(3) Preparation of thermosetting adhesive film 100 g of phenoxy resin (product name YP50S manufactured by Toto Kasei Co., Ltd.) and 150 g of polyfunctional epoxy resin (product name EP180S65 manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent 212) are added to 583 g of ethyl acetate. In a dissolved solution, 250 g of a liquid epoxy resin (epoxy equivalent 185) containing a microcapsule-type latent curing agent was added and stirred, and then fused silica (average particle size 0.5 μm) was added to 100 parts by weight of the resin composition. A thermosetting adhesive resin varnish was prepared by dispersing 100 parts by weight and 2 parts by weight of fine particle silica (average particle size 0.01 μm) with respect to 100 parts by weight of the resin composition. After applying this varnish on the surface of the separator film 7 (product name Teflon film manufactured by DuPont Co., Ltd.) with a roll coater, the varnish was dried in an oven at 70 ° C. for 10 minutes to prepare a thermosetting adhesive film 8. The reaction start temperature of the thermosetting adhesive film 8 was 110 ° C., and the melt viscosity at 150 ° C. was 3400 Pa · s.
(4) Affixing the thermosetting adhesive film The thermosetting adhesive film 8 formed on the surface of the separator film 7 is cut out to approximately the same size as the semiconductor chip, and the adhesive film 8 covers at least a part of the wiring pattern 3. And attached by a thermocompression bonding apparatus (not shown) (see FIG. 1C).
(5) Heat treatment (preheating)
After the separator film 7 was peeled off, the wiring board 3 on which the thermosetting adhesive film 8 was attached was left on a heat stage (not shown) heated to 100 ° C. for 1 minute (see FIG. 1D).
(6) The wiring substrate 3 to which the connection thermosetting adhesive film 8 is attached is fixed to the stage 9 of the ultrasonic bonding apparatus, and the semiconductor chip 4 is bonded to the bonding head 9 so that the gold stud bump 6 and the wiring pattern 2 face each other. And fixed the position. While the stage 10 is heated to 50 ° C. and the bonding head 9 is heated to 150 ° C., the ultrasonic vibration adjusted to a frequency of 50 kHz and an amplitude of 2.5 μm is applied to the wiring substrate 3 while pressing the semiconductor chip 4 to a pressure of 1.8 MPa. The gold stud bump 6 and the wiring pattern 2 were electrically connected to the semiconductor chip 4 for 5 seconds (see (e) and (f) of FIG. 1).
(7) Heat treatment (after cure)
The semiconductor device 11 was produced by leaving it in an oven heated to 150 ° C. for 2 hours (see (g) of FIG. 1).

(1) Preparation of substrate A wiring substrate 3 similar to that of Example 1 was prepared (see FIG. 1A).
(2) Preparation of semiconductor chip having protruding connection terminals A semiconductor chip having gold stud bumps 6 formed on an aluminum electrode 5 was prepared in the same manner as in Example 1 (see FIG. 1B).
(3) Preparation of thermosetting adhesive film Solid epoxy resin (product name EP1004, manufactured by Japan Epoxy Resin Co., Ltd.) in 235 g of 2-butanone in which 350 g of spherical silica (product name QS-4, manufactured by Mitsubishi Rayon Co., Ltd.) was dispersed. Equivalent 875) 120 g, bisphenol A type epoxy resin (Japan Epoxy Resin Co., Ltd., product name EP828, Epoxy Equivalent 185) 235 g dissolved in a solution of imidazole curing agent (Shikoku Kasei Kogyo Co., Ltd. product name 2P4MHZ) 18 g A thermosetting adhesive resin varnish was prepared. After applying this varnish on the surface of a separator film (product name Teflon film manufactured by DuPont Co., Ltd.) using a roll coater (not shown), it is dried in an oven at 70 ° C. for 10 minutes, whereby a thermosetting adhesive film. 8 was produced. The reaction start temperature of the thermosetting adhesive film 8 was 150 ° C., the minimum viscosity at 150 ° C. was 100 Pa · s or less, and the viscosity of 200 Pa · s or less could be maintained for 300 seconds.
(4) Application of thermosetting adhesive film The thermosetting adhesive film 8 was applied to the wiring board 3 in the same manner as in Example 1 (see FIG. 1C).
(5) Heat treatment (preheating)
After the separator film 7 was peeled off, the wiring board 3 to which the thermosetting adhesive film 8 was attached was left on a heat stage (not shown) heated to 150 ° C. for 3 minutes (see FIG. 1D).
(6) After positioning the semiconductor chip 4 and the wiring board 3 in the same manner as in the connection example 1, the semiconductor chip 4 is pressed at 0.9 MPa with the stage 10 heated to 50 ° C. and the bonding head 9 heated to 200 ° C. While pressing against the wiring board 3, ultrasonic vibration adjusted to a frequency of 50 kHz and an amplitude of 2.5 μm is applied to the semiconductor chip 4 for 0.5 seconds to electrically connect the gold stud bump 6 and the wiring pattern 2 (FIG. 1). (See (e) and (f)).
(7) Heat treatment (after cure)
The semiconductor device 11 was manufactured by leaving it in a heated oven at 100 ° C. for 2 hours, 125 ° C., 1 hour, 150 ° C. for 2 hours (see FIG. 1G).

(1) Preparation of Substrate A wiring substrate 14 having a wiring pattern 13 formed on the surface of a glass epoxy substrate 12 was prepared in the same manner as in Example 1 (see FIG. 2A).
(2) Preparation of Semiconductor Wafer A semiconductor wafer 17 having a gold stud bump 16 formed on an aluminum electrode 15 using a gold wire was prepared (see FIG. 2B).
(3) Preparation of thermosetting adhesive film After preparing a thermosetting adhesive resin varnish having the same composition as in Example 1 as a thermosetting adhesive resin, a varnish is applied to the surface of the separator film 18 (not shown). ) And then dried in an oven at 70 ° C. for 10 minutes to produce a thermosetting adhesive film 19.
(4) Application of thermosetting adhesive film and dicing The thermosetting adhesive film 19 formed on the surface of the separator film 18 is attached to the entire bump forming surface of the semiconductor wafer 17 using a roll laminator (not shown). It was. The surface of the semiconductor wafer 17 where the bumps are not formed is attached to the dicing film 20 and the separator film 18 is peeled off, and then a thermosetting adhesive film 19 is attached to the bump forming surface using a dicing apparatus (not shown). The semiconductor chip 21 was cut out (see (c) to (e) of FIG. 2).
(5) Heat treatment (preheating)
The semiconductor chip 21 to which the thermosetting adhesive film 19 was attached was left on a heat stage (not shown) heated to 100 ° C. for 3 minutes.
(6) The semiconductor chip 21 to which the temporarily fixed thermosetting adhesive film 19 is attached is fixed to the head of an alignment apparatus (not shown) heated to 100 ° C., and the wiring board 14 is fixed to the stage of the alignment apparatus. did. After aligning the gold stud bump 16 and the wiring pattern 13, the semiconductor chip 21 was temporarily fixed to the wiring substrate 14 by applying pressure at a pressure of 0.2 MPa for 3 seconds (see FIG. 2F).
(7) The wiring substrate 14 to which the connection semiconductor chip 21 is temporarily fixed is fixed to the stage 22 of the ultrasonic bonding apparatus, the stage 22 is heated to 50 ° C., and the bonding head 23 is heated to 200 ° C. Ultrasonic vibration adjusted to a frequency of 50 kHz and an amplitude of 2.5 μm is applied to the semiconductor chip 21 for 0.5 seconds while being pressed against the wiring board 14 at .8 MPa, and the gold stud bump 16 and the wiring pattern 13 are electrically connected ( (See (g) of FIG. 2).
(7) Heat treatment (after cure)
The semiconductor device 24 was produced by leaving it in an oven heated to 150 ° C. for 2 hours (see (h) of FIG. 2).

(Comparative Example 1)
In Example 1, after connecting the semiconductor chip and the wiring board, a semiconductor device was manufactured without performing heat treatment (after-cure).

(Comparative Example 2)
In Example 2, after connecting the semiconductor chip and the wiring board, a semiconductor device was manufactured without performing heat treatment (aftercuring).

(Comparative Example 3)
In Example 1, a semiconductor device was manufactured without applying ultrasonic vibration.

(Comparative Example 4)
In Example 2, a semiconductor device was manufactured without applying ultrasonic vibration.

(Comparative Example 5)
In Example 2, after connecting the gold stud bump 27 and the wiring pattern 28 without using a thermosetting adhesive film, the aluminum electrode 30 of the semiconductor chip 29 was dissolved by immersing in hydrochloric acid or sodium hydroxide aqueous solution. The semiconductor chip 29 was removed. With respect to the gold stud bump 27 remaining on the wiring pattern 28, a shear test was performed using the shear tool 31 (see (a) to (c) of FIG. 4).

(Comparative Example 6)
In Example 2, after the gold stud bump 33 and the wiring pattern 34 were connected using the thermosetting adhesive film 32, the thermosetting adhesive film 32 was immersed in 2-butanone without performing after-curing treatment. The semiconductor chip 35 was removed by dissolving the aluminum electrode 36 of the semiconductor chip 35 by subsequently immersing it in hydrochloric acid or a sodium hydroxide aqueous solution. With respect to the gold stud bump 33 remaining on the wiring pattern 34, a shear test was performed using a shear tool 37 (see FIGS. 5A to 5D).

  As a result of measuring the reaction hardening rate of the adhesive resin layer of the semiconductor device manufactured in Example 1, Example 3, and Comparative Example 1 by DSC, it was 95% in Example 1 and Example 3, and 30% in Comparative Example 1. It was. Further, these semiconductor devices were left in a bath at 30 ° C. and a relative humidity of 60% for 168 hours and then subjected to IR reflow treatment (265 ° C. maximum) three times. As a result, the semiconductors fabricated in Example 1 and Example 3 While no defect was found in the device, an open defect occurred in the semiconductor device manufactured in Comparative Example 1 (evaluated with five samples).

  As a result of measuring the reaction hardening rate of the adhesive resin layer of the semiconductor device produced in Example 2 and Comparative Example 2 by DSC, it was 95% in Example 2 and less than 10% in Comparative Example 2. In addition, these semiconductor devices were left in a bath at 30 ° C. and a relative humidity of 60% for 168 hours and then subjected to IR reflow treatment (265 ° C. maximum) three times. As a result, the semiconductor device manufactured in Example 2 was defective. On the other hand, in the semiconductor device manufactured in Comparative Example 2, an open defect occurred (evaluated with 5 samples).

  In the semiconductor device manufactured in Comparative Example 3, an open defect occurred before the heat treatment (after cure), and the semiconductor chip and the wiring board could not be electrically connected.

  In the semiconductor device manufactured in Comparative Example 4, an open defect occurred before the heat treatment (after cure), and the semiconductor chip and the wiring board could not be electrically connected.

  In Comparative Example 5, when the gold stud bump and the wiring pattern were connected without using the thermosetting adhesive film, all the bumps were transferred onto the wiring pattern. Further, when the shear strength of the transferred bump was measured (shear speed 200 μm / s), it showed an average of 0.77 N, and the fracture mode was the interface between the bump and the wiring pattern as shown in the photograph (see FIG. 6B). It was not peeling but a break in the gold bump. On the other hand, in Comparative Example 6, when the gold stud bump and the wiring pattern were connected using the thermosetting adhesive film, all the bumps were transferred onto the wiring pattern. When the shear strength of the transferred bump was measured (shear rate 200 μm / s), it showed an average of 0.7 N, and the fracture mode was the interface between the gold bump and the wiring pattern as shown in the photograph (see FIG. 7B). It was not peeling but a break in the gold bump. From the above results, even when the gold stud bump and the wiring pattern were connected using the thermosetting adhesive film, it was confirmed that the bump and the wiring pattern were bonded to each other by ultrasonic vibration.

It is a side view explaining each process of the manufacturing process of the semiconductor device shown in Example 1 and 2. It is a side view explaining each process of the manufacturing process of the semiconductor device shown in Example 3. It is the figure which looked at the position which affixes a thermosetting adhesive film on a wiring board from the top. It is a side view explaining the evaluation method in the comparative example 5. It is a side view explaining the evaluation method in the comparative example 6. It is a photograph which shows the connection part (a) of the semiconductor device produced using the thermosetting adhesive film in the comparative example 5, and the fracture | rupture mode (b) after a shear test. It is a photograph which shows the connection part (a) of the semiconductor device produced using the thermosetting adhesive film in the comparative example 6, and the fracture | rupture mode (b) after a shear test.

Explanation of symbols

1, 12: Glass epoxy board 2, 13, 25, 28, 34: Wiring pattern 3, 14: Wiring board 4, 21, 29, 35: Semiconductor chip 5, 15, 30, 36: Aluminum electrode 6, 16, 27 33: Gold stud bump 7, 18: Separator film 8, 19, 26, 32: Thermosetting adhesive film 9, 22: Joining head 10, 23: Stage 11, 24: Semiconductor device 17: Semiconductor wafer 20: Dicing film 31, 37: Share tool

Claims (7)

In a method for manufacturing a semiconductor device,
(A) a step of preparing a semiconductor chip having a protruding connection terminal, a substrate on which a wiring pattern is formed, and a thermosetting adhesive film;
(B) a step of attaching a thermosetting adhesive film to the substrate surface to form an adhesive resin layer;
(C) After aligning the protruding connection terminals of the semiconductor chip and the wiring pattern on the surface of the substrate, applying ultrasonic vibration in a heated and pressurized state, thereby applying the wiring pattern on the protruding surface of the semiconductor chip and the substrate surface. Electrically connecting the semiconductor chip and the substrate with an adhesive resin layer,
(D) A method for manufacturing a semiconductor device, comprising a step of performing a heat treatment for setting a curing reaction rate of the adhesive resin layer to 80% or more. In a method for manufacturing a semiconductor device,
(A) a step of preparing a semiconductor chip having a protruding connection terminal, a substrate on which a wiring pattern is formed, and a thermosetting adhesive film;
(B) a step of forming an adhesive resin layer by attaching a thermosetting adhesive film to the surface of the semiconductor chip having a protruding connection terminal;
(C) After aligning the protruding connection terminals of the semiconductor chip and the wiring pattern on the surface of the substrate, applying ultrasonic vibration in a heated and pressurized state, thereby applying the wiring pattern on the protruding surface of the semiconductor chip and the substrate surface. Electrically connecting the semiconductor chip and the substrate with an adhesive resin layer,
(D) A method for manufacturing a semiconductor device, comprising a step of performing a heat treatment for setting a curing reaction rate of the adhesive resin layer to 80% or more.   3. The method of manufacturing a semiconductor device according to claim 2, further comprising a step of dividing the semiconductor device into individual semiconductor chips after the step (b).   2. The method of manufacturing a semiconductor device, comprising a step of heat-treating a substrate on which an adhesive resin layer is formed or a semiconductor chip on which an adhesive resin layer is formed before the step (c). 3. A method for manufacturing a semiconductor device according to any one of 3 above.   5. The method of manufacturing a semiconductor device according to claim 1, wherein the heat treatment in the step (d) is at least two stages of heat treatment.   6. The semiconductor according to claim 1, wherein the thermosetting adhesive film is a thermosetting adhesive film having a viscosity of 4000 Pa · s or less at any temperature of 50 to 250 ° C. in the method of manufacturing a semiconductor device. Device manufacturing method. A semiconductor device manufactured by the method for manufacturing a semiconductor device according to claim 1.

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