KR20060104918A - Printed circuit board and method for manufacturing the printed circuit board - Google Patents

Abstract

The printed wiring board of this invention is a printed wiring board in which the wiring pattern which consists of electroconductive metals was formed in the insulating film surface, and the organosilicon compound is affixed on the surface of the said printed wiring board. The printed wiring board of the present invention selectively etches the conductive metal layer formed through the adhesive layer on the surface of the insulating film to form a wiring pattern of a desired shape, and then performs plating treatment on the wiring pattern, and then coexists with the organosilicon compound. It can manufacture by heating and attaching an organosilicon compound to the surface of a printed wiring board.

According to the present invention, it is possible to prevent the growth of a dendrite-like metal between the wiring patterns, so that even if a high voltage is applied, a short circuit due to migration between the wiring patterns is unlikely to occur.

Description

Printed circuit board and method for manufacturing the printed circuit board

1 is a diagram illustrating an example of a printed wiring board on which a comb-shaped electrode is formed.

2 is a cross-sectional view taken along the line A-A of FIG.

3 is a graph showing a change in resistance value when a direct current voltage of 60 V is applied to a printed wiring board at 85 ° C. and 85% RH.

[Short description of reference signs]

10. Printed wiring board

11..Insulation film

13. Adhesive layer

15..wiring pattern

20..Plus play

30..Minus play

The present invention relates to a printed wiring board excellent in migration resistance and a method of manufacturing such a printed wiring board. In more detail, this invention relates to the printed wiring board which has a fine pitch, and is hard to produce the short circuit by a migration even when an applied voltage is high, and the method of manufacturing such a printed wiring board.

With the development of the electronics industry, the demand for printed wiring boards for mounting electronic components such as IC (Integrated Circuit) chips and LSI (Large Integrated Circuit) chips is increasing rapidly.

In such a printed wiring board, there is a high demand for miniaturization, light weight, and high functionality of electronic devices, and wiring patterns formed on the printed wiring board are gradually thinning, and printed wiring boards with pitch widths of less than 30 µm have already been put into practical use. .

Various electronic components are mounted in electronic devices, and the electronic components are generally driven with weak electric power. For example, 50V is applied to electronic components for controlling power circuits and electronic components for driving display devices. Some higher voltages may be applied.

If a high voltage is naturally applied to the printed wiring board mounting such an electronic component, and the wiring pattern interval with the adjacent wiring pattern is narrow, wiring is performed inside the adhesive layer used when the conductive metal foil is adhered to the surface of the insulating film, especially the insulating film. The metal which forms a pattern may grow on a dendrite, reach | attach adjacent wiring patterns, and may short-circuit. It is a short circuit caused by the so-called migration. That is, when a DC voltage of 50 V or more is applied to the wiring pattern, metal ions grow in the dendrite form from the positive electrode pattern toward the negative electrode pattern.

Therefore, it is considered impossible to make the pitch width of a wiring pattern into 50 micrometers or less in the printed wiring board which applies high voltage of 50V or more or 60V or more, and what is called a rough pitch printed wiring board with a pitch width of 50 micrometers or more is generally used.

Thus, the adhesive which is hard to produce the metal diffusion in a dendrite because the metal diffuses into a dendrite form in the adhesive bond layer is also developed. However, such adhesives are very expensive, and in reality, such expensive adhesives cannot be used for printed wiring boards mounted on general electronic devices which are highly competitive.

SUMMARY OF THE INVENTION An object of the present invention is to provide a thinned printed wiring board, which is unlikely to cause a short circuit even when a high voltage is applied.

Moreover, an object of this invention is to provide the method of manufacturing the thinned printed wiring board which a short circuit does not produce even if a high voltage is applied.

The printed wiring board of this invention is a printed wiring board in which the wiring pattern which consists of electroconductive metals was formed in the insulating film surface, and the organosilicon compound is affixed on the surface of the said printed wiring board.

In the printed wiring board of the present invention, the organosilicon compound is preferably attached to at least the adhesive layer surface between the wiring patterns.

The printed wiring board of the present invention selectively etches the conductive metal layer formed through the adhesive layer on the surface of the insulating film to form a wiring pattern of a desired shape, and then performs plating treatment on the wiring pattern, and then coexists with the organosilicon compound. It can manufacture by heating and attaching an organosilicon compound to the surface of a printed wiring board.

By coexisting the printed wiring board with the organosilicon compound in the heat treatment process in manufacturing the printed wiring board of the present invention, the organosilicon compound is adhered to the surface of the printed wiring board, in particular, the conductive metal is removed by etching and exposed to the exposed adhesive layer surface. Moisture becomes difficult to adhere to the surface of the adhesive layer. The growth (diffusion) of the dendrite phase metal is considered to involve moisture adhering to or adsorbing to the adhesive layer. By attaching the organosilicon compound to the surface of the adhesive layer as in the present invention, the surface of the adhesive layer is in a hydrophobized state, whereby a state in which moisture is hardly adhered to the surface of the adhesive layer is formed. Therefore, since there is little growth of a dendrite-like metal in the printed wiring board of this invention, even if a pitch width is 30 micrometers or less and high voltage is applied to 50V or more, it will become difficult to form a short circuit between wiring patterns in the printed wiring board of this invention. .

The organosilicon compound is affixed to the surface of the insulating film of the printed wiring board of the present invention, especially the surface of the adhesive layer formed on the surface of the insulating film, and by moving the organosilicon compound in this manner, the metal moves by migration from the wiring pattern. This is less likely to occur, and a short circuit is unlikely to occur even when the voltage is continuously supplied to the printed wiring board of the present invention for a long time.

In particular, according to the present invention, a printed wiring board in which a wiring pattern is formed with a fine pitch having a pitch width of 30 μm or less, and even a printed wiring board which applies a voltage of 50 V or more, preferably 60 V or more between such wiring patterns, is migrated. The occurrence of short circuit can be prevented.

Next, the printed wiring board of this invention and the method of manufacturing this printed wiring board are demonstrated concretely.

1 is a printed wiring board having a comb-shaped electrode manufactured by the method of the present invention, FIG. 2 is a cross-sectional view schematically showing an A-A cross section which is the cross section, and the pitch width of the comb-shaped electrode is 30 µm.

The printed wiring board 10 of this invention has the insulating film 11 and the wiring pattern 15 arrange | positioned at the surface of this insulating film 11, as shown to FIG.

In the printed wiring board 10 of this invention, the insulating film 11 is a polyimide film, a polyimide amide film, a polyester film, a polyphenylene sulfide film, a polyetherimide film, a fluororesin film, a liquid crystal polymer film, etc. Can be mentioned. That is, these insulating films 11 have acid and alkali resistance to such an extent that they are not corroded to etching solutions used for etching, alkaline solutions used for cleaning, and the like, and are greatly thermally deformed by heating such as when mounting electronic components. It does not have heat resistance. As the insulating film 11 which has such a characteristic, a polyimide film is preferable.

Such insulating film 11 usually has an average thickness of 5 µm to 150 µm, preferably 5 µm to 125 µm, and particularly preferably 25 µm to 75 µm.

In the insulating film 11 as described above, necessary punching holes such as a sprocket hole, a device hole, a bending slit, a positioning hole, and the like are punched out by punching.

The wiring pattern 15 is formed by selectively etching the conductive metal disposed on the surface of the insulating film 11. The conductive metal for forming this wiring pattern 15 is normally arrange | positioned by sticking a conductive metal foil on the surface of the insulating film 11 via the adhesive bond layer 13. Then, by applying a photosensitive resin on the surface of the conductive metal foil and exposing and developing the formed photosensitive resin layer, a desired pattern made of the photosensitive resin cured is formed, and the conductive metal layer is selectively etched using the thus formed pattern as a masking material. The wiring pattern 15 of the form can be formed.

Copper foil, aluminum foil, etc. are mentioned as a conductive metal foil used by this invention. In particular, in this invention, it is preferable to use copper foil as an electroconductive metal foil. As copper foil, generally, it is possible to use an electrolytic copper foil and a rolled copper foil, but in consideration of peeling strength and versatility, it is preferable to use an electrolytic copper foil.

The wiring pattern 15 formed on the printed wiring board of the present invention is a very thin wiring pattern having a pitch width of usually 30 mu m or less, and in order to form such a thin wiring pattern 15, a very thin conductive metal layer It is preferable to form For example, in order to form the wiring pattern 11 whose pitch width is 30 micrometers or less, it is preferable to use the conductive metal foil which has an average thickness of 12 micrometers or less normally, Preferably it is 10 micrometers or less. However, when using an electrolytic copper foil as an electroconductive metal foil, since the thickness of the electrolytic copper foil which can be handled alone is about 15 micrometers, it is the thing which handles a thin electrolytic copper foil alone and sticks to the surface of the insulating film 11 Very difficult.

Therefore, in the present invention, for example, a conductive metal layer, which can be handled alone when the conductive metal layer is formed, is adhered to the surface of the insulating film via the adhesive layer 13 and then formed thereon. It is preferable to form a photosensitive resin layer on the surface of the conductive metal layer thus produced after adjusting the average thickness to 12 µm or less, preferably 10 µm or less by etching.

In addition to the method of forming a wiring pattern by applying a photosensitive resin after adjusting the thickness of the conductive metal layer as described above, a conductive metal layer having a thickness of, for example, 12 µm or less, preferably 10 µm or less, is formed on the surface of the support. Using the laminated conductive metal foil with a support, the adhesive metal 13 is adhered to the surface of the insulating film 11 by adhering the conductive metal layer of the conductive metal with the support to the surface of the insulating film 11 and then peeling the support. A conductive metal layer having a thickness of 12 μm or less, preferably 10 μm or less may be disposed through the via.

For example, by arranging the thin conductive metal layer as described above via the adhesive layer 13 on the surface of the insulating film, a wiring pattern having a pitch width of 30 μm or less, preferably a pitch width of 25 μm to 30 μm can be formed. .

In the present invention, the adhesive layer 13 for adhering the conductive metal foil as described above can be formed using an adhesive that is commonly used when manufacturing a printed wiring board. As an example of such an adhesive agent, an epoxy resin adhesive, a urethane resin adhesive, a polyimide adhesive, an acrylic adhesive, a polyamide adhesive, etc. are mentioned.

The thickness of the adhesive layer 13 formed by such an adhesive is normally 3 micrometers-50 micrometers, Preferably it exists in the range of 6 micrometers-25 micrometers.

In the printed wiring board of the present invention, a conductive metal layer is usually formed by adhering a conductive metal foil using an adhesive as described above, and a photosensitive resin is applied to the surface of the thus formed conductive metal layer to form a photosensitive resin layer. By exposing and developing a resin layer, the pattern of the desired shape which consists of hardened | cured material of the photosensitive resin is formed, and the conductive metal layer is selectively etched using this pattern as a masking material, and the wiring pattern 15 of a desired shape is formed.

In the photosensitive resin layer formed on the surface of the conductive metal layer arranged as described above, there are types in which the light-irradiated portion is cured and types in which the light-irradiated portion is soluble, but any type of photosensitive resin may be used in the present invention. have.

1 and 2 show an example in which the comb wiring pattern 15 is formed by etching the electrolytic copper foil using a pattern made of the photosensitive resin cured as described above. In the printed wiring board 10 shown in FIG. 1, the width W2 of the wiring pattern 15 is 14 μm, the distance W3 from the adjacent wiring pattern is 16 μm, and the pitch width W1 is 30 μm. to be. In addition, the thickness T1 of the wiring pattern 15 formed in this way is 5 micrometers, and it heat-presses the electrolytic copper foil (with an adhesive layer of thickness 12 micrometers) of thickness 15 micrometers which can be handled independently to the surface of an insulating film. After that, an example is used in which the entire surface of the electrolytic copper foil is etched to adjust the thickness of the conductive metal layer to 7 µm.

The present invention is suitable for a printed wiring board having a wiring pattern of the width W2 of the wiring pattern 15, which is usually 5 µm to 25 µm, preferably 10 µm to 20 µm. In addition, the distance W3 from the adjacent wiring pattern at this time is 5 micrometers-25 micrometers, Preferably it is 10 micrometers-20 micrometers, and pitch pitch W1 can be refine | miniaturized to about 25 micrometers or less by thinning copper foil. Can be. Moreover, the thickness of the wiring pattern 15 formed in the printed wiring board of this invention is 5 micrometers-18 micrometers normally, Preferably they are 7 micrometers-15 micrometers. As described above, the wiring pattern 15 formed on the printed wiring board 10 of the present invention has a narrow line width and a narrow pitch width, so that the distance between the wiring pattern 15 and the adjacent wiring pattern 15 is narrow. For example, even when an applied voltage of 50 V or more, and more than 60 V or more, is supplied for a long time, a short circuit due to diffusion of the dendrites is unlikely to occur. On the other hand, the printed wiring board 10 shown in FIG. 1 is a comb pattern for observing occurrence of a short circuit occurring between the wiring patterns 15 with the growth of the dendrites, and the reference numeral 20 denotes a positive voltage load. Pad 30 is a pad for negative voltage load.

The selective etching process of forming the wiring pattern 15 as described above is performed by etching the conductive metal using the cured product of the photosensitive resin as a masking material. The etching liquid used here can be suitably selected and used according to the kind of electroconductive metal. For example, when copper is used as the conductive metal, an etchant mainly composed of ferric chloride and HCl, an etchant such as sulfuric acid + hydrogen peroxide, an etchant mainly composed of cupric chloride + hydrochloric acid + hydrogen peroxide, NaClO ₂ , Ammonia alkali etchant containing Cu (NH ₃ ) ₄ Cl ₂ , NH ₄ OH, NH ₄ Cl and the like can be used.

At the time of an etching process, the insulating film which adhere | attached the conductive metal can also be immersed in etching liquid, It is also possible to spray on the insulating film which adhere | attached the conductive metal, making the said etching liquid into mist shape. Especially in the printed wiring board 10 of this invention, since the thin conductive metal layer is etched and the wiring pattern 15 is formed, it is preferable to spray an etching agent and to perform an etching process.

As described above, when the conductive metal layer is attached to the adhesive layer 13, the wiring pattern 13 is formed from the conductive metal layer, and a direct current voltage is loaded under humidity, the conductive metal grows in the dendrite form in the adhesive layer 13, and the wiring is formed. It becomes a factor which forms a short circuit between the patterns 13. For example, as shown in FIGS. 1 and 2, when a comb-shaped electrode is formed and a direct current voltage is applied to the comb-shaped electrode, a conductive metal grows in the form of dendrites from the positive electrode toward the negative electrode. When a comb electrode is applied with a direct current of 50 V or more and more than 60 V or more at a humidity of 85% RH and a temperature of 85 ° C., the densely comb electrode may be heated for 250 to 450 hours when the pitch width is 30 μm. The insulation state between adjacent wiring patterns is destroyed by the growth of a dry conductive metal. Therefore, when applying the high voltage of 50 V or more of applied voltage, it was considered that the printed wiring board which has the wiring pattern 13 thinned to 30 micrometers or less of pitch width is not suitable. That is, as described above, as shown in FIG. 1, when a comb-shaped electrode having a pitch width of 30 μm or less is formed and a DC voltage of 50 V or more is applied, the dendrite is applied to the adhesive layer 13 between the wiring patterns 15. The metal grows into the phase, and if the temperature and humidity are high, the dendrite phase metal grows in a short time, and in the case of 30 탆 pitch, the dendrite is applied within 500 hours when a direct current voltage of 50 V is applied at 85 ° C. and 85 RH%. It is common for the insulation state between the wiring patterns to be destroyed due to the growth of the phase metal. Therefore, in order to prevent the short circuit which arises in this way, in the printed wiring board whose pitch width is 30 micrometers or less, the voltage applied is restrict | limited and it is not used for the application to which the voltage exceeding 50V or more is applied.

In this way, after performing an etching process, the hardened | cured material of the photosensitive resin used as a masking material is removed by alkali washing. For this alkali washing, an alkali metal aqueous solution of about 3% to 5% can usually be used.

After the wiring pattern 15 is formed as described above, the surface of the formed wiring pattern is usually plated. As the plating treatment performed here, for example, tin plating treatment, solder plating treatment, lead-free / nam plating treatment, nickel plating treatment, gold plating treatment, nickel / gold plating treatment, zinc plating treatment, chromium plating treatment, silver plating treatment, Cu plating treatment Treatment and these composite plating treatments. Especially in this invention, it is preferable to perform tin plating process. The thickness of the plating layer thus formed is usually in the range of 0.01 µm to 1.0 µm, preferably 0.05 µm to 0.6 µm.

After the plating treatment as described above, the printed wiring board of the present invention is heat treated in the presence of an organosilicon compound. Thus, a small amount of organosilicon compound adheres to the printed wiring board surface of this invention by heat-processing in presence of an organosilicon compound.

As an organosilicon compound used here, the organosilicon compound which has a -Si * O- structure can be used, Especially in this invention, it is preferable to heat-process in presence of the organosilicon compound containing polydialkylsiloxane.

In the present invention, the heat treatment conditions are usually 50 ° C to 180 ° C, preferably 70 ° C to 160 ° C, 10 minutes to 120 minutes, and preferably 30 minutes to 90 minutes. Usually, the above heat treatment puts a reel into an oven in the state which wound the printed wiring board with the spacer tape on the reel, and heats it in the above conditions. In this case, a container containing the organosilicon compound is placed in the oven so that the organosilicon compound in the container is also heated together. On the other hand, when the printed wiring board of this invention is plate-shaped, and does not take the form of the above-mentioned tape, of course, it heat-processes without winding to a reel.

Thus, a part of organosilicon compound adheres to the surface of a printed wiring board by heat-processing the printed wiring board of this invention with an organosilicon compound in a sealed oven.

Therefore, for the printed wiring board of the present invention heat-treated in the presence of the organosilicon compound, the measurement of the standardized secondary ion detection intensity using a time-of-flight secondary ion mass spectrometer (TOF-SIMS) + element ion The species Si are usually detected at an intensity in the range of 0.081 to 0.4, preferably in the range of 0.1 to 0.3. As such a + element ion species Si, at least CH ₃ Si, HOSi, C ₃ H ₉ Si, C ₅ H ₁₅ OSi ₂ is detected and heated using an organosilicon compound containing polydialkylsiloxane. By processing such elements can be detected. In the present invention, the measurement conditions of the time-of-flight type secondary ion mass spectrometer (TOF-SIMS) include primary ion species: Ga ⁺ , primary acceleration voltage: 15 kV, primary current: 1 nA, and measurement range: 100 μm × 100 μm. to be.

In the present invention, the organosilicon compound is considered to be attached to the entire surface of the printed wiring board, and in particular, the organosilicon compound as described above adheres to the surface (exposed adhesive layer) of the adhesive layer to which the conductive metal is adhered. As a result, it is assumed that moisture is less likely to adhere to the adhesive layer, the diffusion of the dendrite phase of the metal is inhibited, and as a result, short circuit between the wiring patterns 15 is less likely to occur.

As described above, the printed wiring board is heat-treated in the presence of the organosilicon compound to attach the organosilicon compound to the surface of the printed wiring board, particularly the adhesive layer, and then a solder resist layer is formed or the cover layer is adhered to the wiring pattern. (15) to protect. The solder resist layer is formed by applying and curing the solder resist ink on the wiring pattern 15 using a screen printing technique so that the terminal portion at the end of the wiring pattern 15 is exposed. Moreover, the cover layer adhere | attaches the film which shape | molded the film with an adhesive bond layer previously on the wiring pattern 15 in the shape which the terminal part in the edge part of the wiring pattern 15 is exposed. The edge part of the wiring pattern 15 is exposed in the edge part of the soldering resist layer or cover layer formed in this way, and this exposed wiring pattern is used as an electronic component mounting terminal or an external terminal.

After forming a soldering resist layer or a cover layer as mentioned above, the exposed terminal part is plated normally. Examples of the plating of the terminal portion include tin plating, nickel plating, solder plating, lead-free solder plating, gold plating, nickel and gold plating, zinc plating, chromium plating, silver plating, Cu plating, and composite plating in combination of these. For example, when the bump which is a connection terminal formed in an electronic component, such as IC, is a gold bump, tin plating is performed on the exposed conductor part of a printed circuit board, and the ultrasonic wave is applied while heating, and the tin plating layer of a wiring board conductor is carried out. A gold tin process product is formed by the gold bump of an electronic component, and an electronic component can be mounted on this printed wiring board. In the case where the electronic component is mounted by wire bonding, good wire bonding can be performed using gold wires by gold plating the terminal portions or by nickel and gold plating.

Although the thickness of the plating layer formed in this way can be suitably selected according to the kind of plating, Usually, it is in the range of 0.01 micrometer-1 micrometer, Preferably it is 0.05 micrometer-0.6 micrometer.

On the other hand, in the heating step, the organosilicon compound is also attached to the surface of the wiring pattern, in particular, the terminal portion, but the organosilicon compound attached to the wiring pattern portion is almost removed in the process after the heating process, especially in the plating process. Thereafter, subsequent process operations are not disadvantageous.

3 shows a time-dependent change in the resistance value between wiring patterns when a direct current voltage of 60 V is applied to a printed wiring board having a comb-shaped electrode having a pitch width of 30 µm.

The graph shown by (2) of FIG. 3 shows the time change of the resistance value of the printed wiring board which does not heat in the presence of an organosilicon compound, and the resistance value falls rapidly between 250 hours and 450 hours. On the other hand, the graph shown by (1) is a time change of the resistance value of the printed wiring board of this invention which heated in the presence of an organosilicon compound, and adhered the organosilicon compound, and found the fall of a resistance value until 700 hours passed. It doesn't work. In addition, the measurement test of the said resistance value is 85 degreeC. It is conducted in an environment of 85% RH and this measurement is a facilitation test. Therefore, in this accelerated test, a printed wiring board on which no change in resistance value is found for more than 700 hours can be used without any problem for normal use. On the other hand, as shown in (2) of FIG. 3, a printed wiring board having a reduction time of a resistance value of less than 450 hours is less likely to cause problems in normal use, but there is a fear of insulation failure under strict use conditions, for example. Big.

Thus, the printed wiring board of this invention adheres a trace amount of an organic silicon compound to the surface of a printed wiring board, especially the surface of an adhesive bond layer, for example by heat-processing a printed wiring board in the presence of an organosilicon compound after performing a plating process. You can. Thus, since the organosilicon compound adheres to the surface of a printed wiring board, especially the surface of an adhesive bond layer, it becomes difficult to remarkably attach moisture to the surface of an adhesive bond layer, For example, 50V or more is preferable to the printed wiring board of this invention. Preferably, even if a high voltage of 60 V or more is continuously applied, the dendrite-like metal from the wiring pattern is difficult to grow, and short circuits are unlikely to occur between the wiring patterns.

Therefore, the printed wiring board of this invention can apply a high voltage, even if the wiring pattern formed is very thin.

Specifically, the printed wiring board of the present invention is a tape automated bonding tape (TAB) tape, a tape ball grid array (T-BGA) tape, a chip size package (CSP) tape, an application specific integrated circuit (ASIC) tape, a chip (Chip) It can be applied to on film tape, 2-metal (double-sided wiring) tape, multilayer wiring tape, flexible printed circuit (FPC) tape made of roll-to-roll.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1

Polyimide film (Ube) which coated adhesive (Toray Corporation product, # 7100) with thickness 30mm, electrolytic copper foil (Mitsui Metal Mining Co., Ltd. product, brand name: FQ-VLP) of thickness 15mm at 12 micrometers in thickness It was laminated to Heungsan Co., Ltd. product, a brand name UPILEX, and it hardened in the oven, and produced the three-layer board | substrate. This 3-layer laminated board was etched whole using etching liquid so that copper thickness might be set to 7 micrometers.

Subsequently, a positive photoresist (FR200, manufactured by Rohm and Hers, Inc.) was applied to the entire surface of the copper layer of the three-layer substrate in a thickness of 5 µm to form a photosensitive resin layer.

The photosensitive resin layer formed as mentioned above was exposed to ultraviolet rays using the photomask in which the comb pattern was formed in 30 micrometer pitch, and the pattern which consists of photosensitive resins developed and hardened with KOH solution was formed. The pattern thus formed was used as the masking material.

An etching solution containing cupric chloride, hydrochloric acid, and hydrogen peroxide was sprayed onto the three-layer substrate on which the masking material was disposed, and the copper layer exposed on the surface of the three-layer substrate was selectively etched to form a wiring pattern having a pitch of 30 탆. After etching, the masking material was peeled off by washing with a washing solution containing NaOH, washed with pure water and then pickled.

Subsequently, a tin plating layer having a thickness of 0.45 탆 was formed on the wiring pattern formed as described above using an electroless Sn plating solution (LT-34, manufactured by Rohm and Hers).

The printed wiring board thus obtained was placed in an oven heated to 120 ° C. and heated for 90 minutes. In this oven, an organosilicon compound (Hitachi Chemical Co., Ltd. product, SN9000) was previously placed in an open container. Thus, the printed wiring board was heat-treated in the presence of an organosilicon compound, and the organosilicon compound was made to adhere to the surface of a printed wiring board.

After the heat treatment, a part of the printed wiring board was cut out to prepare a sample, and the sample was placed in a constant temperature and humidity bath (PH-1K, manufactured by ESPEC Co., Ltd.) at 85 ° C and 85% RH while a voltage of 60 V DC was applied thereto. The insulation resistance value was measured.

The results are shown in FIG. 3 (1).

As shown in Fig. 3 (1), the deterioration of the insulation resistance value did not occur for this printed wiring board until 738 hours.

In addition, the same sample as above was cut out from the printed wiring board manufactured as mentioned above, and the surface of this sample was cut into TOF-SIMS (time-of-flight secondary ion mass spectrometer, measurement conditions: primary ion species: Ga ⁺ , primary acceleration voltage: 15 kV, primary current: 1 nA, measurement range: 100 μm × 100 μm), and the organic silicon compounds such as CH ₃ Si, HOSi, C ₃ H ₉ Si, and C ₅ H ₁₅ OSi ₂ were analyzed from the surface of the adhesive layer. Derived Si was detected with an intensity of 0.28.

Comparative Example 1

A printed wiring board was produced in the same manner as in Example 1 except that no organosilicon compound was disposed in the oven during the heat treatment.

As for the obtained printed wiring board, the insulation resistance value was measured similarly to Example 1, and the insulation resistance value fell in 345 hours.

Moreover, the sample was cut out from the manufactured printed wiring board as mentioned above, and the surface of this sample was analyzed by TOF-SIMS, but Si derived from an organosilicon compound was not detected.

The organosilicon compound is affixed on the surface of this adhesive bond layer at least by heat-processing a printed wiring board in the surface of the printed wiring board of this invention in the presence of an organosilicon compound. Thus, adhesion of moisture is prevented by the organosilicon compound adhering to the surface of an adhesive bond layer, and it can prevent that a metal flows out into a dendrite form from a wiring pattern.

Therefore, the printed wiring board of the present invention is capable of migration between wiring patterns even if a very fine pitch wiring board having a pitch width of, for example, 30 µm or less is applied, for example, a high voltage of 50 V or more, preferably 60 V or more. Short circuit due to occurrence is hard to occur.

Claims (20)

A printed wiring board having a wiring pattern made of a conductive metal formed on an insulating film surface, wherein an organosilicon compound is attached to the surface of the printed wiring board. The method of claim 1, The said wiring pattern is formed by selectively etching the conductive metal arrange | positioned through the adhesive bond layer on the insulating film surface, The printed wiring board characterized by the above-mentioned. The method of claim 2, The organosilicon compound is attached to at least the adhesive layer surface between wiring patterns, The printed wiring board characterized by the above-mentioned. The method of claim 1, And a plating layer formed on the surface of the conductive metal, wherein the wiring pattern is selectively etched. The method of claim 1, Standardized secondary ion detection intensity (primary ion species: Ga ⁺ , primary acceleration voltage: 15 kV, primary current: 1 nA) measured using a time-of-flight secondary ion mass spectrometer (TOF-SIMS) on the surface of the printed wiring board. And a measuring element: 100 × 100 μm) + element ion species Si strength is in the range of 0.081 to 0.4. The method of claim 1, The pitch width of the terminal part of the said wiring pattern is 30 micrometers or less, The printed wiring board characterized by the above-mentioned. The method of claim 1, The thickness of the conductive metal which forms the said wiring pattern is 12 micrometers or less, The printed wiring board characterized by the above-mentioned. The method of claim 1, The organosilicon compound adhering to the surface of the printed wiring board is a + element ion species detected by the time-of-flight secondary ion mass spectrometer (TOF-SIMS), and at least CH ₃ Si, HOSi, C ₃ H ₉ Si , C ₅ H ₁₅ OSi ₂ A printed wiring board, which can be obtained. The method of claim 1, The printed wiring board is a printed wiring board, characterized in that the solder resist layer is formed so as to expose the terminal portion of the wiring pattern or the cover layer is adhered. The method of claim 4, wherein The plating layer is a tin plating layer, the thickness of the tin plating layer is in the range of 0.01㎛ 1.0㎛ printed wiring board. The conductive metal layer formed through the adhesive layer on the surface of the insulating film is selectively etched to form a wiring pattern having a desired shape, and then the plating pattern is applied to the wiring pattern, and then heated in the presence of an organosilicon compound to print an organic silicon compound. The manufacturing method of the printed wiring board characterized by sticking to the surface of a wiring board. The method of claim 11, The said heating temperature is set in the range of 70 degreeC-160 degreeC, and a heating time is set in the range of 30 minute-90 minutes, and is heated, The manufacturing method of the printed wiring board characterized by the above-mentioned. The method of claim 11, The organosilicon compound is a polydialkylsiloxane, the method for producing a printed wiring board. The method of claim 11, A printed wiring board characterized by heating in the presence of the organosilicon compound to attach the organosilicon compound to the surface of the printed wiring board, and then forming a solder resist layer or adhering a cover layer to expose the terminal portion of the wiring pattern. Method of preparation. The method of claim 11, A method of manufacturing a printed wiring board, characterized in that the surface of the insulating film is adhered to the surface of the insulating film, and then the entire surface of the conductive metal foil is etched before the selective etching. The method of claim 11, A conductive metal layer is selectively etched to form a wiring pattern so that the pitch width of the terminal portion is 30 μm or less, thereby forming a wiring pattern. The method of claim 11, Standardized secondary ion detection intensity (primary ion species: Ga ⁺ , primary acceleration voltage: 15 kV, primary current: 1 nA,) measured using a time-of-flight secondary ion mass spectrometer (TOF-SIMS) on the surface of the printed wiring board. Measurement range: 100 micrometers x 100 micrometers) The organosilicon compound is made to adhere so that the + element ion species Si intensity may be in the range of 0.081-0.4, The manufacturing method of the printed wiring board. The method of claim 11, And the plating treatment is an electroless tin plating treatment. The method of claim 18, The thickness of the said electroless tin plating layer exists in the range of 0.01 micrometer-1.0 micrometer, The manufacturing method of the printed wiring board. The method of claim 11, A method of manufacturing a printed wiring board, wherein the etching solution is sprayed into a mist when selectively etching the conductive metal layer formed through the adhesive layer on the surface of the insulating film to form a wiring pattern having a desired shape.

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