JPH0821763B2 - Electronic circuit parts - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic circuit board on which, for example, an integrated circuit (IC) or the like is mounted, or an electronic device preferably used for a package in which a semiconductor integrated circuit element is stored, for example. Regarding circuit parts.

2. Description of the Related Art In recent years, in circuit wiring boards and the like, the miniaturization and high density of the circuit wiring formed have been improved more and more. Therefore, the circuit wiring board manufacturing technology has been developed to meet such demand. .

As a first conventional technique for manufacturing such a circuit wiring board, a high melting point metal material such as molybdenum or tungsten is screen-printed on a base material made of, for example, alumina ceramics, and then this is used for 15
A technique of baking at a temperature of about 00 ° C is known.

In such a conventional technique, since the screen printing technique is used to form the circuit wiring, the width of the circuit wiring is required to be at least about 100 μm, and therefore, there is a limitation on miniaturization and high density of the circuit wiring board. There is a problem that it will be done. Another problem with this conventional technique is that the ceramics used for the base material have an extremely high dielectric constant of, for example, about 10, making high-speed signal propagation difficult due to the resistance in the circuit. There is a problem in that high-speed operation of an electronic circuit or the like configured using is impossible.

As a second conventional technique for solving such a problem, for example, a polyimide film is formed on a base material such as ceramics, a metal material is vapor-deposited on the polyimide film, and then etching is performed to form a circuit having a desired pattern. A technique is used in which wiring is formed and this step is repeated to form a single-layer or multilayer circuit wiring board.

Compared with the above-mentioned first conventional technique, such a conventional technique has an advantage that the width of the circuit wiring can be narrowed to about 25 μm, and miniaturization and high density of the circuit wiring board can be improved. Further, the polyimide film that realizes electrical insulation between circuit wirings has a relatively small dielectric constant of 3 to 3.5, so that the signal propagation speed can be increased as compared with the case where the first conventional technique is used, and an electronic circuit configured. The processing speed of can be improved.

In addition, for example, integrated circuits (ICs) and large scale integrated circuits (LS
I), a metal layer as circuit wiring on polyimide resin in an interlayer insulating film or a protective film of a conductor layer on a substrate for electronic circuits on which hybrid integrated circuits and the like are mounted, or a package in which, for example, semiconductor integrated circuit elements are stored. The technique of forming a thin film is widely used. Polyimide resin has relatively high heat resistance and low dielectric constant among polymers from the viewpoint of electrical insulation, and is known to have wide resistance to various processing such as vapor deposition and plating. .

On the other hand, such a second conventional technique has a problem that the reliability of the adhesion strength between the polyimide resin film and the circuit wiring is unduly low. The indication of this problem will be described in detail in the section of Examples to be described later as experimental results in Comparative Examples to be compared with the present invention, but the outline will be given below. For example, a circuit wiring made of a metal material such as chromium, molybdenum, or titanium is subjected to a high-temperature storage test at 150 ° C, and when it is left for about 100 hours due to the oxidation of this wiring metal, the adhesion between the polyimide resin and the wiring metal It was confirmed that the strength was reduced from 5 kg / mm ² to about 1 kg / mm ² .

That is, conventionally, generally used polyimide resin, the general formula, And the functional group R1 is, for example, And the functional group R2 is, for example, Is. As a typical example, a polyimide resin having the following structural formula is generally used.

The above-mentioned conventionally used functional groups are electron-donating, and due to the thermally unstable bond state between such functional groups and metal atoms, the above-mentioned situation occurs. It has occurred.

That is, the bond between the polyimide resin and the metal is adhered by a chemical bond such as ≡C-O-M or ≡C-M, which is formed by donating outer shell electrons of the metal to the carbonyl group part of the polyimide resin. There is. With conventional polyimide resin, The fact that the electron density of the structure is low was confirmed by the present inventors. This fact is due to the fact that XPS (X-ray Photoelectron Spe
Confirmed by ctroscope (ESCA) analysis.

In the manufacturing process of the circuit wiring substrate as described above, a photolithography process and a curing process for forming a polyimide precursor into a polyimide structure are adopted, and these include various heat treatment processes. Further, the heat treatment step is included in the step of packaging the semiconductor integrated circuit element, and a heat generation phenomenon is observed during the operation of the integrated circuit as a product. Therefore, when the adhesion strength between the polyimide resin and the metal layer such as the circuit wiring is deteriorated under such a thermal environment, the circuit wiring is broken or the semiconductor integrated circuit element is peeled from the package. A serious situation will occur.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present invention has been made in view of the above-described problems, and significantly improves the reliability of the adhesion strength between a polyimide resin and a metal thin film, and is a thermal environment. Another object of the present invention is to provide an electronic circuit component whose reliability is significantly improved.

Means for Solving the Problems The present invention is an electronic circuit component formed by forming a metal thin film on a polyimide resin formed on the surface of a base material, wherein the polyimide resin is represented by the general formula: It is an electronic circuit component characterized by being represented by.

However, R1 is R2 is R3 is m and n are natural numbers suitable for forming the polyimide resin.

In a preferred embodiment of the present invention, at least the surface of the metal thin film which is in contact with the polyimide resin is molybdenum (M
o), chromium (Cr), titanium (Ti), tungsten (W), at least one element, or an alloy of two or more of these elements.

Further, a preferred embodiment of the present invention, as the base material,
At least one of ceramics, glass, and metal is selected.

A preferred embodiment of the present invention is characterized in that the polyimide resin layer is formed to have a layer thickness of 2 to 50 μm.

In a preferred embodiment of the present invention, the metal thin film has a thickness of 250.
It is characterized in that it is formed to ~ 4000Å.

Further, a preferred embodiment of the present invention is characterized in that at least one of aluminum (Al), copper (Cu), and gold (Au) is selected for a portion of the metal thin film which is not in contact with the polyimide resin layer.

Operation According to the present invention, the polyimide resin layer is formed on the surface of the base material forming the electronic circuit component, and the metal thin film is formed on the layer. At this time, as the polyimide resin, the kind represented by the third formula is selected. Further, in the third formula, functional groups R1, R2,
R3 is an electron-withdrawing group as described above. Thus, in the polyimide resin having the electron-withdrawing group R1, R2, R3,
Of the third formula The low electron density in the structural portion was confirmed by the inventors of the present invention by the ESCA analysis method as described in the prior art. Further, since the structural portion of the polyimide resin represented by the fourth formula has a low electron density, it becomes easy to receive electrons from the metal atoms of the metal thin film formed on the polyimide resin. Therefore, the polyimide resin and the metal are Outer shell electrons are donated to the carbonyl group of the polyimide to form a chemical bond of ≡C-O-M, or ≡C-M structure. This binding energy differs depending on whether the functional group adjacent to the structural portion represented by the fourth formula has an electron donating property or an electron withdrawing property. That is, if the adjacent functional group is an electron-withdrawing group, the electrons of the structural portion represented by the formula 4 are attracted to the adjacent functional group, and the electron density becomes lower, so that the binding energy between the polyimide resin and the metal atom is reduced. However, it is significantly higher than that of the polyimide resin having an electron-donating functional group described in the section of the prior art. Therefore, even if various treatments are performed at high temperature, the bond between the polyimide resin and the metal atom is not broken, and the reliability of the adhesion strength is dramatically improved.

Further, in the metal thin film formed on the polyimide resin layer, at least the surface in contact with the polyimide resin layer is at least one of molybdenum (Mo), chromium (Cr), titanium (Ti), and tungsten (W), or the like. It is formed from an alloy of two or more of Such a kind of metal may have a higher adhesion strength to the polyimide resin layer than aluminum (Al), copper (Cu), and gold (Au) that constitute a portion of the metal thin film that does not contact the polyimide resin layer. It has been confirmed.

This polyimide resin layer uses a polyimide resin precursor described below, is applied to the surface of the substrate by a so-called spinner method or spray method, by heat treatment at 300 ℃ ~ 400 ℃, to polymerize the polyimide resin precursor A polyimide resin film having a film thickness of 2 to 50 μm having a natural number of m and n suitable as a polyimide resin is formed.
Next, through holes for connection in the case of forming a multilayer structure are formed by photolithography or the like.

The metal thin film formed on this is applied on the polyimide resin layer by using a sputtering method, an ion plating method or the like, and is etched by the photolithography technique. At this time, the photoresist layer used as a mask is peeled and removed. As a result, a desired circuit wiring pattern is realized. By repeating such steps, a multilayer wiring circuit board can be realized.

Example (I) Manufacturing Process of Circuit Board 1 FIG. 1 is a cross-sectional view of a multilayer wiring circuit board (hereinafter abbreviated as circuit board) 1 of an example of the present invention. Referring to FIG. 1, a circuit board 1 includes an insulating substrate 2 made of, for example, a ceramic material, on which a first wiring layer 3 having a structure described later is formed, and a polyimide resin formed on the first wiring layer 3. It is connected to the second wiring layer 6 at a desired position through the through hole 5 of the layer 4. The second wiring layer 6 and the first wiring layer 3 are basically insulated by the polyimide resin layer 4.

Further, the polyimide resin layer 7 is formed on the second wiring layer 6, and the third wiring layer 9 is connected to the second wiring layer 6 at a desired position through the through hole 8 of the polyimide resin layer 7. The combination of such wiring layers 3 and 6 and the polyimide resin layers 4 and 7 formed thereon will be explained as two layers in this embodiment, but in general, the present invention can be applied to a multilayer structure having three or more layers. Are performed similarly.

FIG. 2 is a sectional view taken along the section line II-II in FIG. Referring to FIG. 2, the second wiring layer 6 sandwiched between the polyimide resin layers 4 and 7 is composed of the adhesive layers 10 and 11 which are the surfaces on the side in contact with the polyimide resins 4 and 7 and the adhesive layers 10 and 11. The wiring layer 12 is formed between them. The adhesion layers 10 and 11 are made of at least one element of molybdenum, chromium, titanium, or tungsten, or an alloy of two or more of these elements. In this embodiment, the adhesion layer 10 is made of molybdenum Mo alone, and the adhesion layer 11 is made of chromium Cr alone. The wiring layer 12 is made of at least one of aluminum Al, copper Cu, and gold Au. In this embodiment, the wiring layer 12 is made of a simple substance of copper Cu.

A manufacturing process of the circuit board 1 having the above-described structure will be described with reference to FIGS. 1 and 2.

(1) Manufacturing process of the first wiring layer 3 First, molybdenum-copper is formed on the insulating substrate 2 shown in FIG. 1 by a sputtering method. This is molybdenum with a thickness of 0.
2 μm and copper are formed to a film thickness of 0.4 μm by the same batch continuous sputtering. Subsequently, copper electroplating is performed to a film thickness of 3 μm. Subsequently, chromium is formed to a film thickness of 0.1 μm by sputtering.

(2) Processing Step of First Wiring Layer 3 A so-called negative resist is applied on the multilayer metal thin film obtained as described above by a spinner method. In the spinner method, the insulating substrate 2 on which the multilayer metal thin film is formed is
The resist is adsorbed and fixed on a predetermined stage, the liquid resist is dropped, and then this stage is rotated at 1000 rpm for 10 seconds. Due to the centrifugal force at this time, the liquid resist is uniformly diffused outward in the radial direction, and the resist is applied on the metal thin film with a uniform film thickness. At this time, what is applied is a so-called resist precursor, and it is necessary to vaporize the solvent from this precursor. Therefore, for example, heating at 30 ° C. for 40 minutes in an air atmosphere, so-called prebaking treatment is performed to semi-dry the liquid resist.

Next, in order to form a predetermined wiring pattern, a mask on which a predetermined wiring pattern is drawn is brought into close contact with the resist, and light is irradiated to expose the resist layer. By such so-called contact exposure, a resist pattern having the dimensions of the mask can be obtained. A so-called post-baking process is performed in order to develop the structure including the exposed resist layer by, for example, a xylene-based developer, and then to make the resist material have a structure resistant to the etching process described later. That is, heating is performed at 130 ° C. for 30 minutes in the air atmosphere to thermally crosslink the resist material to form a strong film. Further, this improves the adhesion to the underlying multi-layer metal thin film layer.

Next, the chromium layer having the above-described structure is etched by immersing the substrate on which the metal thin film layer and the resist layer are formed in 36% hydrochloric acid. Next, the copper layer below the chromium layer is etched. This is done by immersion in an aqueous solution of ammonium persulfate, followed by etching of the molybdenum layer. This is done by immersion in an aqueous potassium ferricyanide solution. After the metal thin film layer is completely etched in this manner, the resist layer is immersed in a stripping solution at 80 ° C. for 20 minutes to strip it. The stripping solution used here is of a type that is usually commercially available.

(3) Insulating Layer (Polyimide Resin Layer 4) Film Forming Step A polyimide precursor having a composition described below is applied onto the circuit board 1 after the etching step. This is done, for example, by the spinner method as described above,
The stage is rotated at 2000 rpm for 10 seconds, for example. As a result, the polyimide precursor is applied with a uniform film thickness.
Subsequently, heating is performed at 80 ° C. for 40 minutes in the air atmosphere to vaporize the solvent from the polyimide precursor and semi-dry it.

Then, the semi-dried polyimide precursor is heat-polymerized to mold a polyimide resin. This is to imidize the molecules constituting the polyimide precursor to form a polyimide resin film having a desired polyimide structure. As the processing conditions, for example, a conveyor type continuous furnace is used and heating is performed at 400 ° C. for about 1 hour in a nitrogen gas atmosphere. As a result, the polyimide precursor has a desired polyimide structure and is polymerized to obtain the insulating film (polyimide resin layer 4) having a film thickness of 10 μm.

(4) Processing Step of Insulating Layer (Polyimide Resin Layer 4) In this step, as shown in FIG.
This is a processing step for forming the through hole 5 and the like. Silicon oxide SiO ₂ is sputtered on the polyimide film after the curing treatment so as to have a film thickness of 3 μm. Subsequently, a positive resist is applied by the spinner method (1200 rpm, rotation for 10 seconds), and heated in an air atmosphere at 85 ° C. for 90 minutes to semi-dry the entire resist. Next, the contact exposure described above is performed to form a pattern for forming a predetermined through hole 5 and the like, and development is performed with an alkaline developing solution. Then, heat treatment (post-baking treatment) is performed at 135 ° C. for 30 minutes in the air atmosphere to thermally crosslink the resist material.

After that, it is immersed in an ammonium hydrogen fluoride aqueous solution,
The silicon oxide is etched. Subsequently, in order to peel off the resist layer, it is immersed in a commercially available stripping solution at 60 ° C. for 20 minutes. Then, the polyimide resin layer 4 is etched according to the pattern of silicon oxide. This is done using a reactive ion etching system. Next, the silicon oxide that has been the mask layer for etching the polyimide resin layer is removed. This is done by immersing in the aqueous solution of ammonium hydrogen fluoride.

(5) Film-forming process of second wiring layer 6 and insulating layer (polyimide resin layer 7) This is the first wiring layer 3 and insulating layer (polyimide resin) shown in (I)-(1) to (4) above. This is the same as the film forming process of the layer 4). By repeating this process, the multilayer printed circuit board 1 can be manufactured.

(II) Manufacturing Process of Polyimide Precursor A manufacturing method of the polyimide precursor used in the manufacturing process of the circuit board 1 described in the above (I) will be described.

Weigh 700 g of N-methyl-2-pyrrolidone solvent into 2 flasks. 2,5 diaminonitrobenzene 92g
Is added at 50 ° C. with stirring to dissolve completely. 2,
After the 5 diaminonitrobenzene has completely dissolved, 124 g of pyromellitic anhydride are added in small portions with stirring. Let it react for 30 minutes in this state. Then, the system temperature is raised to 80 ° C. and the reaction is continued for 30 minutes. The inside of this reaction system is a nitrogen gas atmosphere. The polyamidecarboxylic acid thus obtained is used as a polyimide precursor.

Here, n ′ is a relatively small natural number suitable for forming the precursor. Further, an aromatic diamine having one or two electron-withdrawing substituents (nitro group, carbonyl group) can be used instead of 2,5 diaminonitrobenzene. It has been confirmed by the present inventors that the polyimide resin layers 4 and 7 produced using such a polyimide precursor have the characteristics shown in Table 1 below.

(III) Reasons for limiting the film thickness of the polyimide resin layers 4, 7 and the wiring layers 3, 6, 9 (1) Regarding the polyimide resin layers 4, 7 (a) When the film thickness of the polyimide resin layers 4, 7 is 2 μm or less There is a risk that a short circuit may occur between the wiring layers 3, 6 and 9 above and below the pinholes generated in the polyimide resin layers 4 and 7.

When the circuit board 1 shown in FIG. 1 has a multi-layer structure, it is possible to flatten the unevenness due to the pattern formation of the wiring layer on the side of the insulating substrate 2 of a certain polyimide resin layer and the through holes of the similar polyimide resin layer. Therefore, it becomes difficult to finely process the upper metal layer.

When the capacitance increases and a high frequency signal is used, it causes waveform distortion of the signal.

It becomes difficult to control the characteristic impedance. That is,
Characteristic impedance (30-15
It has been confirmed by the present inventor that a film thickness of the polyimide resin layer of 2 to 50 μm is necessary to suppress the thickness to 0 Ω).

(A) When the film thickness is 50 μm or more The volume stress of the polymide resin layer increases, the adhesion of the polyimide resin layer decreases, and peeling occurs.

When the circuit board 1 has a multi-layer structure due to the thermal stress of the polyimide resin layer, stress is applied to the wiring layer in the through hole 8 as shown in FIG. 1, and in the configuration example of FIG. The reliability of electrical conduction between the layer 6 and the first wiring layer 3 is lost.

(2) Thickness of the adhesion layers 10 and 11 (see FIG. 2) (250 to 4000
Å) (a) In the case of 250 Å or less Adhesion layers 10 and 11 (molybdenum, chromium, titanium, tungsten, etc.) and wiring layers 12 (copper, aluminum, gold, etc.)
Are diffused into each other due to heat, and due to the Kirkendall effect, the wiring layer 12 comes into contact with the insulating substrate 2 or the polyimide resin layers 4 and 7 which is the underlying layer, and the adhesion strength is deteriorated.

(B) When the film thickness is 4000 Å or more The residual stress (tensile stress) of the adhesion layers 10 and 11 becomes large, and the stress is concentrated in the corners of the wiring layers 3, 6 and 9 formed in a predetermined pattern. Cracks occur in the polyimide resin layer that is the base.

(3) Regarding the film thickness of the wiring layer 12 of 0.5 to 15 μm (a) When the film thickness is 0.5 μm or less Since the electric resistance value is inversely proportional to the cross-sectional area, in this case, the electric resistance value unnecessarily increases and the circuit board It cannot be used as 1.

(B) When the film thickness is 15 μm or more, the residual stress of the wiring layers 4, 6, 9 formed including the wiring layer 12 becomes large, and cracks are generated in the underlying polyimide resin layers 4, 7, etc. .

When the wiring layer 12 is processed (etched), if the film thickness is large, the degree of etching in the width direction is undesirably increased, which makes fine wiring processing difficult.

(IV) Adhesion Strength Experiment Method The present invention uses the circuit board 1 described with reference to FIGS. 1 and 2 as one embodiment thereof, and the object of the present invention is, for example, the first embodiment. The adhesion strength between the polyimide resin layers 4 and 7 and the wiring layers 3, 6 and 9 above and below the polyimide resin layers 4 and 7 is improved. Therefore, a test piece 13 as shown in FIG. The adhesion strength between 14 and the metal layer 15 was measured.

(1) Method for producing test piece 13 Film-forming step of polyimide resin layer 14 The polyimide precursor described in the manufacturing step in the above (II) section is applied onto an insulating substrate 16 made of, for example, a ceramic material,
Apply by the spinner method described above (2000 rpm for 10 seconds).
Next, heating at 80 ° C for 40 minutes in air (prebaking)
Then, the polyimide precursor is semi-dried. After this, the above-mentioned cure processing is performed. That is, using a conveyor type continuous furnace, heating is carried out at 400 ° C. for a maximum of 1 hour in a nitrogen gas atmosphere, and thermal crosslinking is carried out to form a polyimide resin layer 14 having a film thickness of 10 μm.

Deposition process of metal layer 15 Molybdenum is 0.2 μm on the polyimide resin layer 14.
And copper are formed to a film thickness of 0.4 μm by a sputtering method. Copper is formed thereon by electrolytic plating to a film thickness of 3 μm.

Processing Step of Metal Layer 15 A negative resist precursor is applied on the metal layer 15 by a spinner method (1000 rpm for 10 seconds). afterwards,
Heating (prebaking) is performed at 80 ° C. for 40 minutes in the air atmosphere, and the above-mentioned contact exposure is performed using a 1 μm ² dot pattern mask. After that, development is performed using a xylene-based developer, and heating (post-baking) is performed at 30 ° C. for 30 minutes in the air atmosphere to thermally crosslink the resist.

Copper etching is performed on the resist on which the desired circuit wiring pattern is printed. This is done by immersing in an aqueous solution of ammonium persulfate, and the molybdenum layer is etched by immersing in an aqueous solution of potassium ferricyanide. After that, in order to remove the resist layer, an ordinary commercially available stripper (80
Soak for 20 minutes.

Solder dipping process Dipping is performed by immersing in molten solder (Pb: Sn = 60: 40, 250 ° C) for 5 seconds.

Measurement method A copper wire having a diameter of 1.5 μm is vertically soldered to the metal layer 15 of 1 mm ² described above. Next, after fixing the insulating substrate 16, the copper wire is pulled up vertically in the direction opposite to the insulating substrate 16. In this way, the load applied to the copper wire when the metal layer 15 is peeled off is taken as the adhesion strength.

(V) Measurement result Using a polyimide resin represented by the general formula, a high temperature storage test is performed in an air atmosphere at 150 ° C. At this time, the following third
As shown in the table, the test and the adhesion strength as described in the item of "Measurement method" are performed at each elapsed time. At this time, the functional groups R1, R2 and R3 used in the polyimide resin used according to the present invention and the conventional polyimide resin used as a comparative example are the following second groups.
They are as shown in Tables and Table 3.

The results of the adhesion strength test as described above for various combinations of the functional groups R1, R2 and R3 are shown in Table 4 below.

Symbol "-" in the column of polyimide structure in Table 4
Is a functional group of each of the prior art electron-donating groups shown in Tables 2 and 3 in arbitrary combination.

As described above, in the circuit board 1 of the present embodiment, the adhesion strength between the polyimide resin layers 4, 7 and the wiring layers 3, 6, 9 is improved, and the reliability regarding the adhesion strength even in a thermal environment is improved. Since it is improved, the life of the multilayer printed circuit board 1 can be remarkably extended.

As described above, the polyimide resin layers 4, 7 and the wiring layers 3, 6, 9
Since they realize a stable chemical bond with each other, deterioration of adhesion strength is prevented even during heat treatment in the photolithography process and the polyimide curing process in the manufacturing process of multilayer wiring, and the wiring layer 3 in the manufacturing process is prevented. The peeling of 6,6,9 is prevented.

It is possible to prevent such a situation that a defective connection occurs in the through hole portion of the polyimide resin layer 4 as described above. Further, the deterioration of the adhesion strength of the metal film can be prevented in the heat treatment process for chip attachment of the integrated circuit using the circuit board 1 of this embodiment.

It is possible to prevent the deterioration of the metal film adhesion strength of the die bonding portion, the wire bonding pad and the solder bump portion in the integrated circuit element described above.

In addition, the bond between the polyimide resin and the metal is stable and the reliability after that is significantly improved even by the thermal process when mounting an electronic circuit or the like on the circuit board 1.

FIG. 4 is a plan view of an integrated circuit device 17 according to another embodiment of the present invention, and FIG. 5 is a sectional view taken along the section line VV of FIG. This embodiment will be described with reference to FIGS. 4 and 5. A polyimide resin layer 20, a wiring layer 21, and a polyimide resin layer 22 are formed on an insulating substrate 19 made of a ceramic material or the like through the same steps as the manufacturing steps of the first embodiment described above. A package 18 including such an insulating substrate 19, polyimide resin layers 20 and 22 and a wiring layer 21.
In, the integrated circuit element of the uppermost polyimide resin layer 22
The peripheral portion on the 17 side is peeled off as shown in FIG. 5, and the integrated circuit element 17 and the wiring layer 21 are wire-bonded, for example.

As described above, in the manufacturing process of the package 18 for storing the integrated circuit element 17, various kinds of heat atmosphere are used, and by adopting the manufacturing process shown in the first embodiment, the package 18 is processed. Also, the same effect as the effect described in the above-described embodiment can be realized.

According to the present invention as described above, a polyimide resin layer,
The adhesion strength with the metal thin film formed on the surface has been remarkably improved, and the reliability of the adhesion strength has been remarkably improved as compared with the conventional technology even in a thermal environment. . Therefore, even under various heat treatment processes in the process of manufacturing electronic circuit parts or under heat generation condition processing steps in using the electronic circuit parts as products, the metal thin film realized as circuit wiring or the like is a polyimide resin layer. It is possible to improve the quality and reliability significantly without peeling off.

[Brief description of drawings]

FIG. 1 is a sectional view of a circuit board 1 according to an embodiment of the present invention, and FIG.
FIG. 4 is a sectional view of the vicinity of the second wiring layer 6, FIG. 3 is a sectional view of a test piece 13 for measuring adhesion strength, and FIG. 4 is a package 18 of an integrated circuit element 17 used as another embodiment of the present invention. A simplified plan view and FIG. 5 are sectional views taken along the section line V-V in FIG. 1 ... Circuit board, 2,16 ... Insulation board, 3 ... First wiring layer, 4,7,14,20,22 ... Polyimide resin layer, 5,8 ... Through hole, 6 ... Second Wiring layer, 9 ... Third wiring layer, 10,1
1 ... Contact layer, 12 ... Wiring layer, 17 ... Integrated circuit element, 18
……package

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display area H01L 23/14 H05K 1/05 A

Claims (6)

[Claims] 1. An electronic circuit component comprising a polyimide resin formed on a surface of a base material and a metal thin film formed on the polyimide resin, wherein the polyimide resin is of the general formula: An electronic circuit component characterized by being represented by. However, R1 is R2 is R3 is m and n are natural numbers suitable for forming the polyimide resin. 2. A surface of the metal thin film which is in contact with at least a polyimide resin is molybdenum (Mo), chromium (Cr),
The electronic circuit component according to claim 1, wherein the electronic circuit component is made of at least one element selected from titanium (Ti) and tungsten (W), or an alloy of two or more of these elements. 3. The electronic circuit component according to claim 1, wherein at least one of ceramics, glass and metal is selected as the base material. 4. The electronic circuit component according to claim 1, wherein the polyimide resin layer is formed to have a layer thickness of 2 to 50 μm. 5. The electronic circuit component according to claim 1 or 2, wherein the metal thin film is formed to have a film thickness of 250 to 4000Å. 6. The portion of the metal thin film that does not come into contact with the polyimide resin layer is selected from at least one of aluminum (Al), copper (Cu), and gold (Au). Alternatively, the electronic circuit component according to item 2.