JP5014945B2 - Semiconductor device - Google Patents

Description

  The present invention relates to a semiconductor device, and more particularly to a semiconductor device that suppresses migration of wiring.

  As a semiconductor device in which electronic components are mounted on a wiring board, a semiconductor device (COF: Chip On Film) in which a semiconductor element is bonded and mounted on a flexible wiring board, or a semiconductor in which semiconductor elements are continuously connected on the flexible wiring board An apparatus (TCP: Tape Carrier Package) is known. COF and TCP are mainly applied to a semiconductor device on which a liquid crystal driver IC is mounted.

  In recent years, in order to meet the demand for increasing the number of outputs of a liquid crystal driver, a fine pitch of a wiring pattern of a flexible wiring board on which a liquid crystal driver IC is mounted has been rapidly advanced. At present, COF is more suitable for finer wiring patterns than TCP, and therefore, the liquid crystal driver IC is mainly mounted as COF.

  Hereinafter, a conventional COF assembly method will be described with reference to FIG.

  First, a method for manufacturing the flexible wiring board 50 will be described. First, a metal layer having a barrier function is formed on the polyimide substrate 51 by a sputtering method, and a copper foil is further formed by a metalizing method (copper plating treatment is performed). Next, a photoresist is applied and cured on the copper foil, and then the photoresist is subjected to pattern exposure and developed to form a photoresist pattern having a desired wiring pattern shape. Then, after etching the copper foil and the metal layer having a barrier function according to the photoresist pattern, the desired pattern shape is transferred by peeling the photoresist. Thereby, a barrier layer 52 having a wiring pattern shape and a conductor layer 53 made of copper are formed. The wiring 59 is completed by uniformly applying a tin plating 58 having a thickness of 0.4 to 0.6 μm to the entire surface of the conductor pattern. Further, in order to protect the wiring 59, a solder resist 57 is covered and protected on a portion of the surface of the wiring 59 that is not involved in the connection with the semiconductor chip. Thereby, the flexible wiring board 50 is completed.

  The produced flexible wiring board 50 is bonded to a semiconductor chip on which gold bumps 54 (projection electrodes) are formed. At this time, the tin plating 58 and the gold bump 54 are bonded to tin-gold eutectic. This bonding process is called inner lead bonding (ILB).

  After the ILB, for the purpose of protecting the semiconductor chip 55, an underfill (that is, thermosetting) sealing resin 56 is filled between the semiconductor chip 55 and the flexible wiring board 50, and the sealing resin is applied by heat treatment. Harden.

A final electrical property test is then performed to complete the COF assembly.
JP-A-11-144527 (Publication date: May 28, 1999)

  In such a semiconductor device, recently, further increase in the number of outputs has been demanded, and the voltage applied to the wiring 59 has been increased and the fine pitch of the wiring pattern has been advanced. However, the conventional semiconductor device cannot cope with the high-voltage and fine pitch of the wiring 59, and migration between the wirings 59 has occurred. In migration, when a DC voltage is applied to opposing wires under high humidity, the metal of the wiring material is ionized and eluted by an electrochemical reaction, and the wiring material precipitates and grows at a location that is not the original wiring location. It is a phenomenon that goes on. That is, when the voltage applied to one wiring 59 is increased, the potential difference from the voltage applied to the adjacent wiring 59 is increased, migration is likely to occur between the wirings 59, and the space between the wirings 59 is refined. The electric field intensity exerted on the adjacent wiring 59 by the wiring 59 is increased, and migration is likely to occur.

  When migration occurs, metal ions are also deposited between the wirings 59, thereby causing a short circuit between the wirings 59, resulting in a dielectric breakdown. Therefore, the reliability of the semiconductor device is lost. Therefore, suppressing the occurrence of migration over a long period of time is an important issue in securing the reliability of the semiconductor device.

  As a method for suppressing the occurrence of migration, firstly, in order to prevent high humidity, it is conceivable to provide moisture-proof means for preventing moisture from entering between the wirings. As a moisture-proof means, it can be considered that moisture resistance is imparted to the base material of the flexible wiring board, the solder resist, and the sealing resin, which serve as a moisture intrusion route to the wiring. However, since it is necessary for any of these members to use a water-permeable organic polymer material, it is difficult to completely block the ingress of moisture. In addition, there is a method of applying a waterproof coating, but it requires a lot of labor and cost, and the effect of suppressing migration is insufficient.

  Secondly, there is a method of accelerating the elution of metal ions in the wiring material and reducing the mixing of halogen ions such as chloride ions. However, halogen ions are already mixed in the raw materials used, and it is difficult to completely remove impurity ions such as halogen ions.

  Thirdly, a method of reducing the dissolution rate of metal ions in the wiring material by reducing the electric field strength applied to the wiring is conceivable. However, in order to achieve high-density mounting of semiconductor devices and higher performance of semiconductor chips, it is unavoidable to refine the connection pitch between the mounted semiconductor chip and the flexible wiring board or increase the voltage applied to the wiring. Therefore, it is inevitable that the electric field strength applied to the wiring pattern is increased.

  As described above, in the case of a COF semiconductor device, when the wiring is refined or a high voltage is applied to the wiring, the occurrence of migration cannot be prevented without cost, which hinders the enhancement of the functionality of the semiconductor device. It was.

  On the other hand, in Patent Document 1, in order to prevent migration of silver ions generated in a conductive paste that adheres an electronic component to a substrate, a silver ion binder that forms ionized silver ions and a chain is mixed with the conductive paste. Is described. However, such a conductive paste cannot be applied to semiconductor wiring, and wiring migration cannot be solved.

  An object of the present invention is to provide a highly reliable semiconductor device capable of preventing the occurrence of migration due to deposition of metal ions from wiring.

In order to solve the above problems, a semiconductor device according to the present invention has a COF structure or a TCP structure including a wiring board in which a plurality of wirings are arranged on a base material and a semiconductor element mounted on the wiring board. In the semiconductor device, the substrate is a film-like flexible substrate,
A metal ion binder is applied to the surface of the wiring, and the metal ion binder contains at least one compound selected from benzotriazoles, triazines, and these isocyanuric acid adducts, and is sealed Resin is filled between the semiconductor element and the flexible substrate, enters between the wirings around the connection part of the semiconductor element, and a solder resist is formed between the wirings so as to cover the wiring surface. are entered in form between, and wherein the distance between the wiring Ru der less 50 [mu] m.

Thus, the metal ions of the material released from the wires in contact with the wiring and Sessu that metal ion binding agent, so to capture metal ions, possible to prevent the metal ions are precipitated.

  When metal ions flowing out of the wiring are deposited, the metal grows from the wiring (migration), and finally the wiring is connected to the adjacent wiring. In this case, the insulation between the wirings is destroyed, and the semiconductor element cannot be connected to the external device satisfactorily, causing malfunction.

  According to the present invention, metal deposition from such wiring is prevented, so that metal growth is also prevented, and the semiconductor device does not cause such a malfunction. In addition, since such semiconductor devices are required to have finer wiring and higher voltage, the present invention can improve the performance of the semiconductor device by preventing the deposition of metal ions from the wiring. It becomes.

  The semiconductor device of the present invention further includes a sealing resin disposed between the wiring substrate and the semiconductor element so that at least a part thereof is in contact with the wiring, and the sealing resin includes a metal ion binder. It is characterized by including.

  Here, the sealing resin is generally provided for the purpose of protecting the wiring board, the semiconductor element, its connecting portion, and reinforcing the connection.

  According to this, since the metal ion binder is contained in the sealing resin, the metal ion binder contained in the sealing resin can act on the wiring. That is, the metal ions flowing out from the wiring come into contact with and captured by the metal ion binder in the sealing resin, so that the metal ions remain in the sealing resin and do not precipitate.

  Therefore, deposition of metal ions from the wiring can be prevented only by adding a metal ion binder to the sealing resin without increasing the number of manufacturing steps and the number of members in the conventional semiconductor device. Therefore, the growth of the metal from the wiring is prevented, and the malfunction of the semiconductor device is prevented.

  The semiconductor device of the present invention is characterized in that, when the sealing resin is filled between the wiring substrate and the semiconductor element, the viscosity is 50 mPa · s or more and 1250 mPa · s or less.

  The sealing resin is cured after being filled without a gap between the wiring board and the semiconductor element in a state of fluidity before curing. Therefore, even when a metal ion binder is added, it should preferably have fluidity that can be filled without any gaps.

  Therefore, before the sealing resin is cured, that is, when it is filled between the wiring board and the semiconductor element, by setting the viscosity within the above range, it can be easily applied and there is no gap between the wiring board and the semiconductor element. The sealing resin is provided with fluidity that can be filled completely.

  When the viscosity is less than 50 mPa · s, there is a problem that the fluidity is too high and the sealing resin flows out or cannot adhere to the semiconductor element side, particularly to the side surface of the semiconductor element. On the other hand, if the viscosity is greater than 1250 mPa · s, the fluidity is too low to easily flow out of the dispenser, and voids may remain in the sealing resin.

  In the semiconductor device of the present invention, the sealing resin contains the metal ion binder in an amount of 0.5 wt% to 10.0 wt%.

  According to this, it can be easily applied in a state before curing, has fluidity that can be filled without a gap between the wiring board and the semiconductor element, and has a sufficient migration suppressing effect by the metal ion binder. .

  When the content of the metal ion binder is lower than 0.5% by weight, the effect of suppressing migration is insufficient, and when the content is higher than 10% by weight, the viscosity becomes high and it is difficult to apply. May remain.

  In the semiconductor device of the present invention, the wiring is formed on the surface of the base material, and the base material contains a metal ion binder.

  According to this, since the metal ion binder is contained in the base material, the metal ion binder contained in the base material can act on the wiring. That is, the metal ions flowing out from the wiring come into contact with the metal ion binder in the base material and are captured, so that the metal ions remain in the base material and do not precipitate.

  Therefore, precipitation of metal ions from the wiring can be prevented only by adding the metal ion binder to the base material without increasing the number of manufacturing steps and the number of members in the conventional semiconductor device. Therefore, the growth of the metal from the wiring is prevented, and the malfunction of the semiconductor device is prevented.

Further, the semiconductor device of the present invention may comprise a metal ion binding agent on SL solder resist.

  Here, the solder resist is generally provided to prevent a short circuit or disconnection in the wiring, and covers an area that is not electrically connected in the wiring to prevent adhesion of dust or mechanical stress. It is to prevent receiving.

  According to this, since the metal ion binder is contained in the solder resist, the metal ion binder contained in the solder resist can act on the wiring. That is, the metal ions that have flowed out of the wiring come into contact with the metal ion binder of the solder resist that comes into contact with the metal ions and are trapped, so that the metal ions remain in the solder resist and do not precipitate. Therefore, the growth of the metal from the wiring is also prevented, so that the malfunction of the semiconductor device is prevented.

  Therefore, by adding a metal ion binder to the solder resist material without increasing the number of manufacturing steps and the number of members in the conventional semiconductor device, the growth of the metal from the wiring can be prevented and the malfunction of the semiconductor device can be prevented. Can be removed.

  The semiconductor device according to the present invention is characterized in that the metal ion binder includes at least one compound selected from benzotriazoles, isocyanuric acid adducts of benzotriazoles, and isocyanuric acid adducts of triazines. .

According to this, since these compounds can be captured by forming a complex with metal ions that flow out of wiring such as copper ions, precipitation can be prevented .

  Moreover, the semiconductor device of the present invention is characterized in that the semiconductor element is mounted on the wiring board by a tape carrier method.

  Here, the tape carrier system is one in which semiconductor element mounting regions are arranged in the longitudinal direction of a tape-like flexible substrate. This method is advantageous for automation of semiconductor device manufacturing because semiconductor elements can be mechanically continuously mounted in the mounting area when a semiconductor is mounted, and the product can be handled reel-to-reel. It is.

  In such a semiconductor device, in recent years, with higher density mounting, higher functionality, and higher output, there has been a demand for particularly finer wiring pitch and higher voltage. Preventing the precipitation can improve the performance of the semiconductor device.

  Further, the semiconductor device of the present invention is characterized in that a liquid crystal display element is mounted.

  In such a semiconductor device, a fine pitch and a high voltage of the wiring are particularly required. Therefore, according to the present invention, it is possible to improve the performance of the semiconductor device by preventing the precipitation of metal ions from the wiring. .

As described above, the semiconductor device of the present invention is a semiconductor device having a COF structure or a TCP structure, including a wiring board having a plurality of wirings arranged on a base material and a semiconductor element mounted on the wiring board. , The substrate is a film-like flexible substrate,
A metal ion binder is applied to the surface of the wiring, and the metal ion binder contains at least one compound selected from benzotriazoles, triazines, and these isocyanuric acid adducts, and is sealed Resin is filled between the semiconductor element and the flexible substrate, enters between the wirings around the connection part of the semiconductor element, and a solder resist is formed between the wirings so as to cover the wiring surface. The interval between the wirings is 50 μm or less.

Thus, the metal ions of the material released from the wires in contact with the wiring and Sessu that metal ion binding agent, so to capture metal ions, possible to prevent the metal ions are precipitated. Therefore, the growth of metal from the wiring is also prevented, so that the malfunction of the semiconductor device is prevented.

  The present invention forms a complex with a metal ion in order to solve the problem of causing migration due to ionization and precipitation of wiring material in a semiconductor device of a system such as COF (Chip On Film). The metal ion binder is mixed in the main constituent material in contact with the wiring, or the surface of the wiring is uniformly coated. Thereby, precipitation of metal ions due to migration can be suppressed, and a highly reliable COF that can cope with finer wiring patterns and higher voltages can be provided.

  An embodiment of the present invention will be described below with reference to FIGS.

  1A is a plan view of the semiconductor device of the present invention, FIG. 2 is a cross-sectional view taken along the plane AA ′ in FIG. 1A, and FIG. 3 is a cross-sectional view taken along line BB in FIG. 'A cross-sectional view of the plane.

  As shown in FIG. 2, the semiconductor device 11 of the present invention includes a flexible wiring substrate 10, a semiconductor chip 5, and a sealing resin 6.

  The flexible wiring board 10 is formed by laminating a plurality of wirings 9 and a solder resist 7 in this order on a base film (base material) 1. The wirings 9 are formed so that the semiconductor chip 5 can be properly connected to an external device. This is a mounting board. The base film 1 is a film made of polyimide and serves as a base material for the flexible wiring board 10. The wiring 9 can be connected to the semiconductor chip 5 on which one end is mounted, and the other end can be connected to an external device, whereby the semiconductor chip 5 and the external device are electrically connected. That is, the gold bump 4 and the wiring 9 on the semiconductor chip 5 are bonded by forming a gold-tin eutectic alloy by thermocompression bonding. The solder resist 7 is a protective cover for preventing the wiring 9 from being short-circuited or disconnected.

  Here, the wiring 9 is linearly formed on the surface of the base film 1 so as to go from the mounting position of the semiconductor chip 5 toward the side of the base film 1. The wiring 9 includes a barrier layer 2, a conductive layer 3, and a tin plating 8. The barrier layer 2 is a layer made of a chromium-nickel alloy provided on the base film 1 side of the wiring 9. The barrier layer 2 has a function of protecting the conductor layer 3 and a function of improving the adhesion of the wiring 9 to the base film 1. The conductive layer 3 is made of copper and has a function of leading electricity well in the wiring 9. Tin plating 8 is applied to the entire surface of the conductive layer 3. The wiring 9 has a fine pitch of 30 μm between adjacent wirings 9.

  Further, the solder resist 7 is provided on the base film 1 so as to cover the wiring 9, and the formation position is a peripheral portion slightly spaced from the mounting position of the semiconductor chip 5. In this way, the solder resist 7 prevents short-circuiting and disconnection by protecting all areas of the wiring 9 that are not electrically connected. In other words, when the distance between the wires 9 (wiring pitch) is a narrow pitch of about 30 μm, for example, shorting due to dust from the outside or disconnection due to mechanical stress from outside tends to occur. The solder resist 7 protects it. The solder resist 7 also has a function of improving the electrical insulation characteristics of the wiring 9 and the bending resistance of the flexible wiring board 10.

  The semiconductor chip 5 has protruding bumps 4 made of gold on the joint surface with the flexible wiring board 10. In the semiconductor chip 5, the bump 4 is bonded to the wiring 9 by thermocompression bonding on the flexible wiring substrate 10 by forming a gold-tin eutectic alloy. As a result, one end of the wiring 9 is mounted with being connected to the semiconductor chip 5.

  The sealing resin 6 is located between the side surface and the bonding surface of the semiconductor chip 5 and the mounting surface of the flexible wiring board 10 and has a function of protecting the semiconductor chip 5.

  Here, a method for manufacturing the semiconductor device 11 will be described.

  The semiconductor device 11 is formed in a line in the longitudinal direction of a polyimide film 40 with a long sprocket hole 41 as shown in FIG. That is, the semiconductor chip mounting area is formed in a line on the polyimide film 40, and the semiconductor chip 5 is mounted on this mounting area. At the time of use, the individual semiconductor chips 5 are separated together with the polyimide film 40 at the broken line portions to form the semiconductor devices 11 shown in FIG. In addition, in the following description, the part in the broken-line part in the polyimide film 40 and the polyimide film after cut | disconnecting are called the polyimide base material 1. FIG.

  The manufacturing method will be described in detail. As shown in FIG. 2, first, a metal layer made of a nickel-chromium alloy is formed on the polyimide substrate 1 by sputtering. Then, a copper foil is formed on the surface of the metal layer by a metalizing method (that is, a copper plating process is performed). Next, a photoresist is applied / cured on the copper foil, and then a wiring pattern is pattern-exposed / developed on the photoresist to form the photoresist in a desired pattern shape. Then, the metal layer and the copper foil are etched according to the photoresist pattern, and then the photoresist is stripped. Thereby, a desired pattern shape is formed in the metal layer and the copper foil. Then, the entire pattern thus formed is plated with tin 8 having a thickness of 0.4 to 0.6 μm to form the wiring 9. Further, the solder resist 7 is coated on the periphery of the wiring 9 spaced from the mounting region of the semiconductor chip 5.

  Then, the semiconductor chip 5 is bonded to the mounting region of the semiconductor chip 5 by the gold-tin eutectic of the bump 4 (projection electrode) provided on the semiconductor chip 5 and the tin plating 8 of the wiring 9. In addition, this heating / compression bonding step using gold-tin eutectic is called inner lead bonding (ILB).

  After the ILB, for the purpose of protecting the semiconductor chip, an underfill (that is, thermosetting resin) sealing resin is filled between the semiconductor chip 5 and the flexible wiring substrate 10, and the sealing resin is cured by heat treatment. .

  Thereafter, a final connection test is performed to complete the assembly of the semiconductor device.

  In the semiconductor device manufactured in this manner, particularly in a high temperature and high humidity environment, the metal contained in the wiring 9 (that is, the metal that is the material of the barrier layer 2, the conductor layer 3, and the tin plating 8) is ionized, and the metal Ions (mainly copper ions) are easily generated. As shown in FIG. 4, the metal ions are deposited outside the wiring 9 and appear as a deposited metal 20 between the wirings (migration), which causes the electrical insulation with the adjacent wiring 9 to be broken. The dielectric breakdown due to migration is likely to occur when the distance between the wirings 9 is 50 μm or less, particularly 30 μm or less. Therefore, in order to prevent the precipitation of the metal ions, the metal ions can be captured by the metal ion binder before the generated copper ions are precipitated.

  That is, when producing at least one member in contact with the wiring 9, the metal ion binder is mixed with the material of the member or applied directly to the wiring 9. The members in contact with the wiring 9 are the sealing resin 6, the base film 1, the solder resist 7, and the like.

  For example, as shown in FIG. 2, the sealing resin 6 is filled between the semiconductor chip 5 and the flexible wiring substrate 10, and enters between the wirings 9 around the connection portion of the bump 4 of the semiconductor chip 5. Yes. Therefore, if a metal ion binder that forms a complex with metal ions is mixed in the sealing resin 6, the metal ions that flow out from the wiring 9 to the sealing resin 6 are contained in the sealing resin 6. Captured by the binder. Thereby, the metal ion solubility in the sealing resin 6 increases. That is, more metal ions are allowed to flow into the sealing resin 6 and remain. Therefore, an increase in metal ions in the wiring 9 can be suppressed, and precipitation of metal ions from the entire wiring 9 can be delayed.

  Similarly, since the solder resist 7 is formed so as to cover the wiring 9 as shown in FIGS. 2 and 3, the solder resist 7 enters between the wirings 9. Therefore, if a metal ion binder that forms a complex with metal ions is mixed in the solder resist 7, the metal ions that flow out from the wiring 9 to the solder resist 7 become the metal ion binder contained in the solder resist 7. Be captured. Thereby, the metal ion solubility in the solder resist 7 increases. That is, more metal ions are allowed to flow into the sealing resin 6 and remain. Therefore, metal ions in the wiring 9 can be suppressed, and deposition of metal ions from the entire wiring 9 can be delayed.

  Further, since the base film 1 has the wiring 9 formed on the surface thereof, it is in contact with the entire barrier layer 2 of the wiring 9. Therefore, if a metal ion binder that forms a complex with metal ions is mixed in the base film 1, the metal ions that flow out of the wiring 9 and flow on the base film 1 are the metal ion binders. Captured. Thereby, the metal ion solubility in the base film 1 increases. That is, more metal ions can remain in the base film 1. Therefore, an increase in metal ions in the wiring 9 can be suppressed, and deposition of metal ions can be delayed.

  Further, by applying a metal ion binder to the wiring 9, the metal ions flowing through the wiring 9 are captured by the metal ion binder. Thereby, increase of the metal ion in the wiring 9 can be suppressed, and precipitation of a metal ion can be delayed. In addition, as a method of applying a metal ion binder to the wiring 9, a method of immersing the flexible wiring board 10 in a metal ion binder solution immediately after forming a wiring pattern in the manufacturing process of the flexible wiring board 10, or a metal ion The method of apply | coating a binder to the wiring 9 surface by spraying is mentioned.

  Thus, if the precipitation of metal ions flowing out from the wiring 9 is suppressed, the electrical insulation between the wirings 9 of the semiconductor device is stabilized even in a high humidity environment, and a short circuit can be suppressed.

  As the metal ion binder, a compound that forms a complex with copper ions or other metal ions may be used. Thereby, for example, generated copper ions are captured by forming a complex with the metal ion binder, and copper is prevented from being deposited between the patterns of the wiring 9. Therefore, electrical connection with the adjacent wiring 9 is prevented.

  Examples of the metal ion binder include benzotriazole, triazine, or isocyanuric adducts thereof.

  The benzotriazole series includes 1H-benzotriazole-1-methanol (chemical formula (2)), which is an adduct of methanol, as well as the basic form of benzotriazole represented by chemical formula (1), and an alkyl group added to the triazole side. And those having an alkyl group added to the benzene side (Chemical Formula (4)).

  The triazine system is represented by the chemical formula (5). For example, 2,4-diamino-6-vinyl-S-triazine represented by the chemical formula (6) or 2,4-diamino compound represented by the chemical formula (7) is used. Examples include diamino-6- [2′-ethyl-4-methylimidazole- (1)]-ethyl-S-triazine and 2,4-diamino-6-methacryloyloxyethyl-S-triazine represented by the chemical formula (8). It is done.

  The isocyanuric acid adduct is obtained by adding isocyanuric acid represented by the chemical formula (9) to the above triazine-based or benzotriazole-based compound. An isocyanuric acid adduct of a triazine-based compound is represented by the chemical formula (10). For example, 2,4-diamino-6-vinyl-S-triazine isocyanuric acid represented by the chemical formula (11) or the chemical formula (12) 2,4-diamino-6-methacryloyloxyethyl-S-triazine shown.

  An experiment for examining the migration suppression effect of these metal ion binders will be described below. In the experiment, a comb-tooth wiring pattern for measuring electrical insulation shown in FIG. 5A was used. In the comb-tooth wiring pattern, a substrate 30 made of polyimide, a comb-tooth electrode 31a connected to the cathode, and a comb-tooth electrode 31b connected to the anode are 30 μm apart from each other (distance C in FIG. 5B). It is formed as follows. The comb electrodes 31a and 31b are obtained by tin plating on copper having a thickness of 8 μm.

  This comb-teeth wiring pattern is equivalent to the wiring pattern of the semiconductor device, and the ease of occurrence of wiring migration in the semiconductor device can be observed in a pseudo manner, and migration can be measured as a leakage current. That is, when metal ions flowing out from the comb electrodes 31a and 31b precipitate and migrate, a metal grows between the comb electrodes 31a and 31b as shown in FIG. The electrodes 31a and 31b are connected. At this time, when a voltage is applied to the comb-tooth electrodes 31a and 31b, the leak current increases rapidly. Therefore, the connection between the comb-tooth electrodes 31a and 31b can be observed by measuring the leak current.

  In the experiment, the metal ion binders shown in Table 1 were dispersed in pure water so as to have a predetermined concentration, and a predetermined amount was dropped on the entire surface of the comb-tooth wiring pattern uniformly. After the dropping, a predetermined DC voltage was applied to the comb-tooth electrodes 31a and 31b, and then left in an indoor environment, and a change in leak current value was measured every predetermined time. The results are shown in Table 1.

  According to this, the pure water of the comparative example has no migration suppressing effect, and benzotriazole, 1H-benzotriazole-1-methanol, 2,4-diamino-6-vinyl-S-triazine and isocyanuric acid are very There was a good migration suppression effect. Also, 2,4-diamino-6-methacryloyloxyethyl-S-triazine isocyanuric acid, 2,4-diamino-6- [2′-ethyl-4-methylimidazole- (1)]-ethyl-S-triazine There was also an effect of suppressing migration. Furthermore, a slight migration suppressing effect was also observed in 2-vinyl-4,6diamino-S-triazine.

  Next, for a metal ion binder having a very excellent migration suppressing effect, the dissolution with a resin (property that can be dispersed without agglomeration by mixing) was investigated. As a result, benzotriazole, 1H-benzotriazole-1-methanol was Good compatibility with resin and well dispersed in resin. On the other hand, 2,4-diamino-6-methacryloyloxyethyl-S-triazine / isocyanuric acid had poor compatibility with the resin and was difficult to disperse in the resin.

  When such a metal ion binder having poor compatibility with the resin component is mixed with the resin component, the metal ion binder does not disperse in the sealing resin but aggregates, resulting in a state in which the metal ion binder exists non-uniformly. In particular, 2,4-diamino-6-vinyl-S-triazine / isocyanuric acid adducts are difficult to mix with resin components such as acid anhydrides, and tend to cause aggregation. Accordingly, when such a resin, for example, the sealing resin 6 is used, a portion where the capture of metal ions is difficult to occur is generated.

  Therefore, when a metal ion binder that is difficult to disperse in the resin, such as 2,4-diamino-6-vinyl-S-triazine / isocyanuric acid adduct, is used as the metal ion binder. Must be finely pulverized and uniformly dispersed and mixed. At this time, the metal ion binder is preferably pulverized until the average diameter is 0.5 μm or less, more preferably 1 μm or less. Furthermore, in order to prevent aggregation of the metal ion binder, it is also effective to perform a filtration treatment using a 1 μm mesh fine cut filter. Further, as a mixing method for finely pulverizing and uniformly dispersing the metal ion binder, it is preferable to knead the sealing resin using a roll mill device or a bead mill device and perform a mixing process.

  Next, the case where a metal ion binder is mixed with the sealing resin 6 will be described as an example, and the production of the sealing resin material mixed with the metal ion binder will be described.

  As a resin component of the sealing resin 6, an epoxy resin, an acid anhydride, or the like is used. To this, the above-described metal ion binder, dye, and curing accelerator in the form of fine powder are added and kneaded. The blending ratio may be, for example, 99.6% by weight of the epoxy resin and the curing agent, 2.5% by weight of the metal ion binder, and 0.9% by weight of the dye and the curing accelerator.

  Here, in the sealing resin 6, the content of the metal ion binder capable of satisfactorily suppressing migration and obtaining good fluidity was examined.

  First, the content of the metal ion binder necessary for exhibiting the migration suppressing function was examined. As an experimental method, 2,4-diamino-6-vinyl-S-triazine isocyanuric acid adduct as a metal ion binder was added to an epoxy resin at 0, 0.5, 1.5, 2.5, 5 Prepare a resin added so as to be 0.0, 10.0, 15.0% by weight, uniformly cover the entire surface of the comb-teeth wiring pattern of FIG. 5, and apply a DC voltage of 40 V in an atmosphere of 85 ° C. The leakage current was examined by leaving it in an environment of 85% RH. Here, a roll mill or a bead mill apparatus was used for mixing the metal ion binder and the resin. These resins are mainly composed of an epoxy resin and a metal ion binder. As the metal ion binder 0% by weight, the epoxy resin and the curing agent are 99.3% by weight, the dye and the curing accelerator. In which 0.7% by weight is contained.

  The results are shown in FIG. The horizontal axis in FIG. 7 is the standing time, and the vertical axis is the result of measuring the change in the insulation resistance value between the comb electrodes 31a and 31b calculated from the leakage current. According to this, in the resin without the addition of a metal ion binder, dielectric breakdown occurred due to migration due to copper deposition generated from the wiring after 500 hours. On the other hand, it can be seen that the resin added with 0.5% of the metal ion binder did not cause dielectric breakdown until 700 hours later, and the migration of the wiring 9 was delayed. And in resin containing 1.5% of a metal ion binder, after good insulation was maintained until 900 hours later, the insulation deteriorated. Therefore, the decrease in insulation was further delayed, and the insulation was not completely destroyed until the observed 1000 hours. Other resins having a metal ion binder addition amount of 2.5 wt% or more had stable electrical insulation even after 1000 hours as observed. That is, it was found that as the amount of the metal ion binder added increases, the electrical insulation is better even in a high temperature and high humidity environment. Therefore, in order to apply a resin containing a metal ion binder and obtain a good migration suppression effect, the resin preferably contains 0.5% by weight or more of the metal ion binder, particularly 2.5 wt. % Or more is preferable.

  Next, the content in the metal ion binder capable of maintaining the fluidity required for the sealing resin was examined. That is, the above-described metal ion binder has a function of forming a complex with a metal ion, and when mixed with a resin, promotes curing of the resin from its molecular structure. Accordingly, if the metal ion binder is mixed too much with the sealing resin 6, the viscosity of the sealing resin 6 increases excessively, and it becomes difficult to fill the sealing resin 6. That is, the sealing resin 6 is filled between the semiconductor chip 5 and the flexible wiring board 10 by a dispenser. However, when the viscosity of the sealing resin 6 is high, stable discharge from the dispenser cannot be performed. Further, the sealing resin fills the gap between the semiconductor chip 5 and the flexible wiring board 10 without gaps due to its fluidity. However, when the viscosity of the sealing resin 6 is high, the fluidity becomes low, and the semiconductor It becomes impossible to fill the sealing resin between the chip 5 and the flexible wiring board 10 without a gap. Therefore, when mixing a metal ion binder with the sealing resin 6, it is necessary to consider the increase in viscosity so that the fluidity is not impaired. Note that the viscosity of the sealing resin 6 suitable for emphasis is 50 mPa · s or more and 1250 mPa · s or less, and more preferably 200 mPa · s or more and 1000 mPa · s or less.

  For this purpose, in the sealing resin 6, it is preferable to mix so that it may become 10 weight% or less, and it is more preferable to mix so that it may become 5 weight% or less.

  Here, the result of measuring the viscosity of the sealing resin in which 2,4-diamino-6-vinyl-S-triazine / isocyanuric acid adduct was added to the epoxy resin as a metal ion binder by 0 wt% to 15 wt% was measured. It shows in Table 2. The sealing resin used here is mainly composed of an epoxy resin and a metal ion binder.

  According to this, the sealing resin (0% by weight) containing no metal ion binder has a viscosity of 850 mPa.s. In contrast to s, the viscosity of the sealing resin increases in correlation with the amount of the metal ion binder added. When the metal ion binder is 5% by weight or less, the viscosity is 1000 mPa.s. The resin dischargeability (property that the resin flows out from the dispenser) and the filling property (property that can fill the space between the semiconductor chip 5 and the flexible wiring board 10 without gaps) are good. However, when the metal ion binder is 10% by weight, the viscosity is 1250 mPa.s. s, and the resin discharge stability and filling properties are slightly impaired. And when a metal ion binder will be 15 weight%, a viscosity will be 1500 mPa.s. s, and the resin cannot be discharged smoothly from the dispenser. Furthermore, when the space between the semiconductor chip 5 and the flexible wiring substrate 10 is filled, a portion that cannot be partially filled as shown in FIG. 8 is generated, and bubbles 21 are formed in this portion. Thus, if bubbles 21 are formed between the semiconductor chip 5 and the flexible wiring board 10, the semiconductor chip 5 is not reliably fixed to the flexible wiring board 10, and connection failure may occur. In addition, moisture accumulates in the bubbles, which may cause a reduction in the reliability of semiconductor chip protection.

  Moreover, in order to suppress the increase in the viscosity of the sealing resin, there is a method of adjusting the action of the curing accelerator used for the sealing resin. For example, it is conceivable to suppress the curing reaction at low temperatures by impregnating the components of the curing accelerator in capsules or to suppress the curing reaction at low temperatures by adjusting the molecular structure of the curing accelerator.

  Furthermore, the resin life may be shortened and the impurity ion concentration may be prevented from increasing by adjusting the viscosity of the sealing resin and the effect accelerator to be added.

  In addition, when mixing the metal ion binder into the solder resist 7, when the material of the solder resist 7 is in a state before being cured, by mixing 0.5% by weight or more of the metal ion binder and then curing it, It becomes a solder resist capable of suppressing migration of the wiring 9. In addition, when the solder resist 7 is formed by printing, it is preferable that the mixing of the metal ion binder is 10.0% by weight or less so as to obtain characteristics suitable for printing.

  Moreover, when mixing a metal ion binder with the base film 1, before the material of the base film 1 hardens | cures, it mixes 0.5 weight% or more of metal ion binders, and is hardened after that, and the wiring 9 Migration can be suppressed. In this case, the metal ion binder is preferably mixed in an amount of 10.0% by weight or less in order to ensure material characteristics.

  Moreover, when apply | coating a metal ion binder to the wiring 9, it is preferable to mix a metal ion binder of 0.5 weight% or more, using a pure water as a solvent, for example. Thereby, migration of the wiring 9 can be suppressed.

  As described above, the present invention can suppress the dielectric breakdown with the adjacent wiring even in the fine pitch wiring. Therefore, the present invention can be particularly preferably applied to a semiconductor device in which a base material is a flexible substrate, a tape carrier type semiconductor device, and a semiconductor device equipped with a liquid crystal display blocking, which require finer wiring and higher voltage.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. Embodiments are also included in the technical scope of the present invention.

  In addition, the present invention can be configured as follows.

  In a semiconductor device in which a semiconductor element is mounted on a film-like flexible substrate on which a wiring pattern is formed, in order to improve the electrical insulation characteristics between the wiring patterns, in a sealing resin for protecting a semiconductor chip, in a solder resist, or A first semiconductor device characterized in that a migration inhibitor (metal ion binder) is added to, mixed in, or applied to the surface of the wiring pattern in the base substrate.

  In the first semiconductor device, the migration inhibitor used is a benzotriazole, triazine, isocyanuric acid, a substance having a composition of triazine and isocyanuric acid adduct, a sealing resin, a solder resist, or a base substrate. A second semiconductor device characterized by being added to, mixed with, or applied to the surface of the wiring pattern.

In the first or second semiconductor device described above, in the sealing resin, the solder resist, or the base substrate in order to suppress the increase in the viscosity of the resin and the aggregation of the migration inhibitor that occur when the migration inhibitor to be used is added. The migration inhibitor is 0.5 to
3. A third semiconductor device using a material added and mixed by 10.0% by weight.

  In the first semiconductor device, in order to suppress the increase in viscosity that occurs when the migration inhibitor used as a protective sealing resin is added into the resin, a curing accelerator having an effect of suppressing the increase in viscosity is used. The fourth semiconductor device is characterized by being protected by a sealing resin having a viscosity of 50 to 1250 mPa · s after viscosity adjustment.

  In a semiconductor device in which a semiconductor element is mounted on a film-like flexible substrate on which a wiring pattern is formed, in order to improve electrical insulation characteristics between wiring patterns, a migration inhibitor is used on the surface of the wiring pattern on the flexible substrate. A fifth semiconductor device characterized by using a flexible substrate that has been subjected to a surface treatment (impregnated or sprayed with a migration inhibitor) and coated with a migration inhibitor on the surface of the wiring pattern.

  In the first to fifth semiconductor devices, the film-like flexible substrate is in the form of a long tape, and the semiconductor device is a tape carrier type semiconductor device in which semiconductor elements are continuously mounted on the flexible substrate. 6. Semiconductor device of 6.

  A seventh semiconductor device according to any one of the first to fifth semiconductor devices, wherein the semiconductor device is a liquid crystal module semiconductor device on which a liquid crystal display element and peripheral components are mounted.

  The semiconductor device of the present invention is suitable for a semiconductor device having a narrow wiring pitch, for example, a semiconductor device or a tape whose base material is a flexible substrate, because it prevents metal deposition from wiring and prevents dielectric breakdown between wirings. The present invention can be applied to a carrier type semiconductor device and a semiconductor device equipped with liquid crystal display blocking.

(A) is a top view which shows the semiconductor device concerning embodiment of this invention, (b) is drawing which shows the state mounted in the tape carrier in the manufacturing process of this semiconductor. It is sectional drawing which shows the A-A 'cross section of the semiconductor device of Fig.1 (a). It is sectional drawing which shows the B-B 'cross section of the semiconductor device of Fig.1 (a). It is a top view which shows the semiconductor device which raise | generated migration. It is a top view which shows the comb-tooth wiring board for measuring the migration suppression effect of sealing resin, (a) is drawing which expanded the A section of the whole (b). It is a top view which shows the case where the comb-tooth wiring of FIG. 5 raise | generated migration. It is drawing which shows the migration inhibitory effect of sealing resin containing a metal ion binder. It is sectional drawing which shows sealing resin containing the bubble at the time of filling a semiconductor device with sealing resin with high viscosity. It is sectional drawing of the conventional semiconductor device.

Explanation of symbols

1 Base film (base material)
5 Semiconductor chip (semiconductor element)
6 Sealing resin 7 Solder resist 8 Tin plating 9 Wiring 10 Semiconductor device 11 Flexible wiring board (wiring board)

Claims (7)

A wiring board in which a plurality of wires are arranged on a base material;
In a semiconductor device having a COF structure or a TCP structure, including a semiconductor element mounted on the wiring board,
The substrate is a film-like flexible substrate,
A metal ion binder is applied to the surface of the wiring,
The metal ion binder includes at least one compound selected from benzotriazoles, triazines, and these isocyanuric acid adducts,
A sealing resin is filled between the semiconductor element and the flexible substrate, and is inserted between the wirings around the connection part of the semiconductor element.
Furthermore, the solder resist is formed so as to enter between the wirings so as to cover the wiring surface,
A semiconductor device, wherein an interval between the wirings is 50 μm or less.   The semiconductor device according to claim 1, wherein the sealing resin has a viscosity of 50 mPa · s or more and 1000 mPa · s or less when filled between the wiring substrate and the semiconductor element.   The semiconductor device according to claim 1, wherein the metal ion binder has an average diameter of 1 μm or less. The wiring is formed on the substrate surface,
The semiconductor device according to any one of claims 1 to 3, wherein the base material contains a metal ion binder. The metal ion binding agent is a semiconductor device according to claim 1, characterized in that the 1H- benzotriazol-1-methanol in any one of four. Semiconductor device, the semiconductor device according to any one of claims 1, characterized in that mounted on the wiring board by a tape carrier system 5. The semiconductor device according to any one of 6 claim 1, characterized in that the liquid crystal display device is mounted.

Images