JPH08288102A - Electronic component and its manufacture - Google Patents

Abstract

PURPOSE: To provide an electronic component and its manufacturing method with which edge part electrodes can be formed, regardless of a manufacturing process and functional element material, the fine pattern edge part electrodes and the multilayer edge part electrodes can be realized easily, the high precision, the high reliability, the size reduction, the low profile, the cost reduction, etc., can be achieved and, further, the multilayer structure of electrodes corresponding to various purposes can be realized easily. CONSTITUTION: Edge part electrodes 5 which are connected to extraction electrodes 3 or to internal electrodes are formed on the edge part of a chip or a substrate 1 which has functional elements at least either in the interior or on the surface. Photoresist layers are formed on the areas on the edge part of the chip or the substrate 1 except the areas for the extraction electrodes 3 or the internal electrodes by an intaglio printing method, a screen printing method or a photolithography method. Then conducting material is deposited by a vacuum film forming method and, after that, the photoresist layers are removed to form the edge part electrodes 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitor formed inside or on the surface of a chip made of an insulating material (including a magnetic material or a dielectric material) or a printed board.
Inductor or resistor or composite of these,
The present invention relates to an electronic component in which an end electrode is provided at an end of a chip on which one or more functional elements are formed, and a manufacturing method thereof, and more particularly, to an end electrode and a forming method thereof.

[0002]

2. Description of the Related Art A method of forming electrodes on the end surface of a chip is
To describe a resistance network having a plurality of end electrodes, there are the following three examples. (Example 1) On the surface of the same insulating substrate, silver to be the upper electrode, silver /
Palladium, a conductor paste such as gold, a resistance paste such as ruthenium oxide to be a resistor, and a glass paste to be a protective film, by a series of thick film process of firing by screen printing, the upper electrode, A plurality of resistors and a protective film are formed. After that, a conductor paste made of silver, silver / palladium, gold, or the like is attached to the end of the convex chip by dipping, dipping, or the like, dried, and then baked to form an end electrode. (Example 2) A through hole serving as an end electrode is provided on an insulating substrate made of alumina or the like, and when the conductor paste is printed on the through hole portion, the conductor paste is sucked from the lower surface of the through hole at that time so that the entire through hole is formed. The conductive paste is wrapped around, then dried and fired. And
A plurality of resistors and a protective film are formed by a series of thick film processes in which a resistance paste is printed on the conductor layer of the through hole portion so that the end portions overlap each other, and a glass paste is printed on the resistance paste and baked. After that, the through hole portion is divided into two by dividing along the snap groove formed on the substrate in advance or by dicing or laser scribing to form a concave end electrode. (Example 3) An upper electrode, a plurality of resistors and a protective film are formed on the same insulating substrate by a thick film process, and the substrate is divided into chips by snap grooves, dicing, and laser scribing which are formed on the substrate in advance. To do. If necessary, the edge may be chamfered by a barrel. After that, the conductor paste is directly transferred and printed on the end surface of the chip by intaglio printing or screen printing, and an end electrode is formed through a series of thick film processes.

The end electrodes formed by the above method are plated with nickel and tin or solder to form a surface mount resistance network. In addition to the capacitor (C) and the resistor (R), an inductor (L) or a surface mount electronic component in which a functional element is formed by laminating two or more of these by a thick film process,
The end electrodes are formed by the same method.

[0004]

As described above, since the end electrodes are conventionally formed by the thick film process, there are the following problems. (1) Vapor deposition, sputtering, ion plating,
When forming passive elements such as resistors, capacitors, and inductors by a vacuum film forming method (thin film process) such as CVD, firing conditions for end electrodes (in air, 600 ° C. to 900 ° C.)
At (° C.), there are problems such as oxidation of the film formed by the vacuum film formation method and evaporation of the composition material, and it is difficult to use both thin and thick film processes together. For this reason, it is impossible to obtain superiority in the case of the thin film process, that is, superiority in electrical characteristics, reliability, stability of the thin film and in-plane distribution of resistance value. Also, in thick film processes such as screen printing, there is a limit in pattern resolution and positional accuracy, and the advantage of miniaturization and low profile by the photolithography technology that enables fine pattern formation and high density cannot be used We cannot meet the demands for higher precision, higher reliability, and lower prices. (2) When a resin such as polyimide, epoxy, or phenol is used for the protective film, if the end electrodes are formed by a thick film process, there is a problem in the heat resistance of the resin, and a low melting point metal or fusible material is used. When a material having no resistance to the heat history at the time of forming the end electrodes by the thick film process is used, there is a problem in heat resistance as in the case of the resin. (3) It is difficult to form an end electrode with a narrow pitch in forming an end electrode having an uneven shape or an intaglio plate or an end electrode by screen printing, because there are limitations in processing accuracy of an insulating substrate, transfer, and printing. (4) When a conductor paste is used to form the end electrodes, there are problems that there are few selection options of the paste and that the end electrodes cannot have a multilayer structure, and the adhesion to the adherend substrate, that is, the end portion However, it is difficult to obtain ohmic contact at the junction between the electrode and the lead-out electrode or the internal electrode, and it is impossible to take measures such as forming a barrier layer having a role of preventing diffusion between materials. (5) Since a printed circuit board in which a copper plating film or a rolled foil is processed on a substrate made of glass epoxy, phenol, etc. has a low heat resistance temperature, it is difficult to directly form the substrate by a thick film process. There is a problem that the surface mounting type cannot be formed unless a material for taking out such as a frame is used.

In view of the above-mentioned problems, the present invention can form the end electrodes regardless of the manufacturing process or the material for forming the functional element, which facilitates fine patterning and multi-layering of the end electrodes. An object of the present invention is to provide an electronic component and a manufacturing method thereof, which can achieve high precision, high reliability, downsizing, low profile, low price, etc., and can easily form a multi-layered electrode according to various purposes. And

[0006]

In the electronic component of the present invention, an end electrode connected to a take-out electrode or an internal electrode is provided at the end of a chip or substrate having a functional element formed on at least one of the inside and the surface thereof. The electronic component to be formed is characterized in that the end electrode is formed by a vacuum film forming method.

Further, according to the method of manufacturing an electronic component of the present invention, a lead-out electrode or an end electrode connected to the internal electrode is formed at the end of a chip or substrate having a functional element formed on at least one of the inside and the surface thereof. In the method of manufacturing an electronic component, a lift-off resist is formed by an intaglio printing method, a screen printing method or photolithography in an area excluding the extraction electrode or the internal electrode on the end surface of the chip or the substrate, and then conductive by a vacuum film forming method. The end electrodes are formed by depositing the body and then removing the lift-off resist.

[0008]

In the present invention, the end electrodes are formed by the vacuum film formation method, and in performing the vacuum film formation,
The lift-off method is used. The lift-off resist is formed by
It can be formed at a low temperature by any of the intaglio printing method, the screen printing method and the photolithography method. Further, since the subsequent conductor film is also formed by the vacuum film forming method, it can be formed at a low temperature in all the steps of forming the end electrodes. Therefore, restrictions on manufacturing processes and materials are alleviated. Further, by using the film forming apparatus for a multilayer film, a multilayer end electrode structure can be adopted. Further, when the film is formed by the vacuum film forming method, it is possible to solve the problem of resistance to plating during barrel plating and the problem of ohmic contact with the connection portion with the extraction electrode or the internal electrode in the case of the thick film process. Further, the lift-off resist is formed by a method of embedding and transferring the resist in an intaglio plate molded with a silicone resin or the like, or a method by screen printing, according to the chip size, the chip shape, or the end electrode pitch to be formed. Either a photoresist effective for forming a fine pattern or a forming method using a photolithography technique is selected.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1A is a perspective view showing an embodiment of an electronic component according to the present invention, and FIGS.
FIG. 6 is a sectional view taken along line EE and FF of FIG. In this embodiment, a nickel-chromium resistance film 2 and an upper electrode 3 as a take-out electrode are formed on an insulating substrate 1 made of alumina or the like by a vacuum film forming method such as vapor deposition or sputtering, and formed on the resistive film 2. The protective film 4 made of an epoxy resin is covered so that a part of the upper electrode 3 is exposed, and the upper electrode 3 is divided into individual chips.
Is formed. Here, the end electrode 5 is formed by using a thin film formed of copper or silver by a lift-off method as a base film, and nickel plating and tin plating or solder plating on the base film.

FIGS. 2 and 3 are process diagrams showing the method of manufacturing the electronic component of FIG. 1 in a cross-sectional view or a plan view for one chip, respectively. As shown in the cross-sectional view of FIG. A nickel-chromium-based thin film 2 serving as a resistance film is formed on an alumina substrate or a dielectric substrate 1 having an electrode inside alumina by vapor deposition or sputtering.
Next, as shown in the cross-sectional view of FIG. 2B, a copper thin film 3a to be a base film of the upper electrode is formed by vapor deposition or sputtering. Next, as shown in the sectional view of FIG. 2C, after the photosensitive resist 6 is formed on the entire surface, as shown in the sectional view of FIG. 2D and the plan view of FIG. The exposed copper thin film 3 is exposed and developed so that the copper thin film 3a serving as the underlying film of FIG.
A nickel film 3b is formed on a by plating, and then the resist 6 is peeled off as shown in the sectional view of FIG.

The surface of the substrate 1 on which the resist 6 has been peeled off is covered with a nickel film 3b and a base film 3a made of a copper thin film. From this state, the copper thin film 3a is etched with an aqueous solution of ammonium persulfate to form a film. 2 (H)
As shown in the cross-sectional view of FIG.
The copper thin film 3a other than the portion covered with b is removed, and the lowermost nickel-chromium thin film 2 is exposed.

Next, as shown in the sectional view of FIG. 2 (J), a photosensitive resist 6 is applied again, and the resistance pattern is exposed, developed and baked, and the cerium nitrate-based etching for dissolving the nickel-chromium thin film 2 is performed. Etching with solution, Figure 2
As shown in the plan view of (K), the nickel-chromium thin film 2
To form a resistance pattern. Then, as shown in the cross-sectional views of FIGS. 2 (K) and 2 (L), epoxy is applied to an area excluding a part of the upper electrode 3 and a cut margin (scribe line) during dicing for the purpose of protecting the resistance pattern. After printing a system resin or the like by screen printing, the resin is cured to form the protective film 4.

The substrate 1 on which the protective film 4 has been formed is cut into a desired chip shape by dicing, and if necessary, barrel processing is performed to chamfer the chip edge portion.

The next step, which is the formation of the end electrodes 5, is shown in FIG.
As shown in the side view (corresponding to the left side view or the right side view of FIG. 2L) of FIG. 2A and the part of FIG. Mask it. There are three masking methods. One of them is a method of embedding a lift-off resist 8 in an intaglio plate made by molding a silicon resin and transferring it to the end of the substrate 1 to cure it, and the second is a lift-off resist 8 by a screen plate having a masking portion patterned. Print,
The third method is a method of applying a lift photoresist 8 capable of forming a fine pattern and utilizing a series of photolithography techniques such as exposure, development, and baking.

As shown in FIG. 3 (B), the chip on which the lift-off resist 8 has been deposited as described above is provided with the upper electrode 3 formed on the surface of the chip and the vapor deposition mask 9 in which the entire surface of the end is opened. Then, as shown in FIG. 3 (C), a thin film 5a made of copper or silver is sputtered (or vapor-deposited). Before depositing the thin film 5a, a nickel-chromium film or a chromium film is formed as a base film, and thereafter, a film having high conductivity such as copper or silver is continuously formed to form the substrate 1. In some cases, the adhesiveness of copper is increased, and diffusion of copper or silver is prevented. Further, a copper-nickel film or the like may be formed on the thin film 5a made of copper as an acid resistant and antioxidant film.

Next, the chip adhered to the entire surface of the end portion of the substrate 1 and the upper electrode 3 is immersed in a solution that dissolves the lift-off resist 8 or is ultrasonically peeled off, and FIG.
As shown in (D), the lift-off resist 8 is removed. Since the end electrode manufactured by the above method is the thin film 5a, the nickel film 5b and the tin film 5c are formed by barrel plating as shown in FIG. 3E, or the end electrode is formed as shown in FIG.
Solder plating 5d is applied as shown in FIG.

As the substrate 1, a glass epoxy resin, a phenol resin, or a substrate for a hybrid integrated circuit is used.
The end electrode 5 may be formed in the same process as described above.

Thus, by forming the end electrodes 5 by using the lift-off method, even if the resistance film 2 and the upper electrode 3 are formed by the thin film process as in the above embodiment, the resistance film 2 and the upper electrode 3 are formed. It is possible to form a resistance network by a thin film process without the problem of oxidation of No. 3 and evaporation of the composition material. Therefore, thin film electronic parts with superiority in electrical characteristics, reliability and stability can be obtained. Moreover, the photolithography technology enables fine patterns, downsizing and height reduction, and high precision in the market. It is possible to meet demands for higher cost, higher reliability, and lower prices.

When a low melting point metal material or a fusible material is used for the resistance film 2 or the upper electrode 3 or a resin such as polyimide, epoxy or phenol is used as the protective film 4, a resin substrate such as glass epoxy or phenol is used. Even when using, the end electrode 5 can be formed.

Further, as described above, a film for the purpose of forming a film for the purpose of preventing the conductive metal from diffusing or forming a film having a close contact strength with the substrate as a base film of the conductor film 5a of the end electrode 5 or a covering film for covering the conductor film 5a. As a cover film, various films for the purpose of improving acid resistance and oxidation resistance can be formed, and the problem of ohmic contact at the joint portion in the case of conventional printing or baking can be solved.

FIG. 4A is a perspective view showing an embodiment in which the present invention is applied to a capacitor chip, and FIGS. 4B and 4C are sectional views taken along line HH and II of FIG. In FIG. 4, reference numeral 11 is a dielectric material such as alumina or barium titanate, which is selected in accordance with the purpose such as dielectric constant, and 12 is a dielectric material 11.
Internal electrodes 5 made of a metal such as copper, silver, silver / palladium, or gold incorporated therein are end electrodes. Dielectric 11
The internal electrode 12 and the internal electrode 12 are formed by a thick film process of laminating and firing by a screen printing method or a sheet method, or by a photolithography technique, a vacuum film forming method, or a thin film process by plating.

The end electrode 5 is formed by forming a thin film of copper, silver or the like by a lift-off method, and then forming a nickel film and a tin film on the end of the chip made of the dielectric 11 as described with reference to FIG. Alternatively, it is formed by applying solder plating.

FIG. 5A is a perspective view showing another embodiment of the present invention, and FIG. 5B is a sectional view taken along the line JJ, showing a spiral type thin film coil 16 on a substrate 15 made of a magnetic material. The end electrode 5 is formed by the lift-off method as well as the first embodiment.

FIG. 6A shows another embodiment of the present invention.
An inductor, a capacitor, a resistor, etc. are provided inside or on the surface of the chip 17 made of an insulator (which is constructed or used as a dielectric or a magnetic material depending on the purpose) so as to form one inductor, a capacitor, a resistor or the like. One functional element composed of these combinations is formed, and a pair of end electrodes 5 is formed by the method of the above embodiment.
Further, this functional element may be formed not only by a thick film process or a thin film process but also by using a metal foil or a semiconductor process, and the functional element may be configured as an active element.

[0025]

According to the present invention, since the end electrodes of the electronic component are formed by the vacuum film forming method, it is possible to perform the manufacturing process such as a thin film process, a thick film process, a process using a metal foil, and a semiconductor process. In addition, the end electrodes can be formed regardless of the functional element constituent material such as the resinous substrate and the low melting point material. For this reason, the degree of freedom in designing electronic components is expanded, and it is possible to form functional elements using photolithography technology, and it is possible to meet the demand for higher precision.
Further, it is possible to maintain high reliability without the problem of performance deterioration caused by the heat of burning the end electrodes as in the prior art. Further, it becomes easy to make the end electrodes finely patterned and multilayered, and it becomes possible to meet the demands for downsizing, low profile, high density, and low price of electronic components. Further, it is possible to easily form a multilayer film according to the purpose, such as improving the adhesion strength of the end electrodes, preventing diffusion, improving acid resistance and oxidation resistance. Further, various requirements can be met by selecting the resist forming method by the lift-off method according to the chip size, the chip shape, and the end electrode pitch.

[Brief description of drawings]

FIG. 1A is a perspective view showing an embodiment of an electronic component according to the present invention, and FIGS. 1B and 1C are EE of FIG.
It is a FF sectional view.

FIG. 2 is a process drawing showing a part of the manufacturing process of the embodiment of FIG.

FIG. 3 is a process drawing showing the remaining steps of the manufacturing process of the embodiment in FIG.

4A is a perspective view showing another embodiment of the electronic component according to the present invention, and FIGS. 4B and 4C are H- of FIG.
It is H, II sectional drawing.

5A is a perspective view showing another embodiment of the electronic component according to the present invention, and FIG. 5B is a sectional view taken along line JJ of FIG.

6 (A), (B) and (C) are perspective views showing another embodiment of the present invention.

[Explanation of symbols]

1: Dielectric substrate, 2: Resistive film, 3: Upper electrode, 4 Protective film, 5: End electrode, 6: Photosensitive resist, 8: Lift-off resist, 9: Mask, 11: Dielectric, 12: Internal electrode , 15: magnetic material substrate, 16: spiral coil, 1
7: Chip

Claims (2)

[Claims] 1. An electronic component in which an end electrode connected to a lead-out electrode or an internal electrode is formed at an end of a chip or a substrate having a functional element formed on at least one of the inside and the surface thereof. An electronic component characterized by being formed by a vacuum film forming method. 2. A method of manufacturing an electronic component, wherein an end electrode connected to a take-out electrode or an internal electrode is formed at an end of a chip or a substrate having a functional element formed on at least one of the inside and the surface thereof. After forming a lift-off resist by an intaglio printing method, a screen printing method or photolithography in an area on the end surface of the chip or the substrate excluding the extraction electrodes or internal electrodes, a conductor is deposited by a vacuum film forming method, and then the lift-off resist is formed. By removing
A method for manufacturing an electronic component, which comprises forming an end electrode.