JPH10163002A - Chip electronic component and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure good connection of an inner conductor film to terminal electrodes, and prevent peeling thereof due to soldering by forming the film so that an exposed part of the film at the end face inclines to a cut face. SOLUTION: An inner conductor film 11 is formed on the surface of an insulative substrate 10 and covered with a protective layer 12. A conductor film 16 is formed at a cut face to make electrode electrodes. A plated layer 17 is formed so that an exposed part of the conductor film of the film 11 at the end face inclines to the cut face. A terminal electrode 16 is formed at that part to connect the conductor film 11 to the terminal electrode 16. Trenches are formed into the surface of the protective layer of a wafer having the inner conductor film and protective layer at the insulative substrate surface, deep enough to reach the substrate through the inner conductor film. The substrate is divided at the trenches into separate elements and terminal electrodes are formed thereafter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a chip-type electronic component such as an inductor, a capacitor or a resistor and a method of manufacturing the same, and more particularly, to a method of improving the strength of external terminal electrodes to enhance reliability. It is.

[0002]

2. Description of the Related Art Various electronic parts are required to be formed into chips, and various chip-type elements are used in the field of passive elements such as resistors, capacitors and inductors. In addition, a technique of forming a capacitor, an inductor, and the like by forming an internal conductor film on the surface of an insulating substrate in a single layer or in multiple layers via a thin film has also been used.

[0003] In such an electronic component, an internal conductor film serving as a large number of elements is formed on one insulating substrate, and the surface is covered with a protective layer such as glass, and then divided into individual elements. Since the end of the internal conductor film is exposed on the cut surface when the division is performed, a terminal electrode is formed on this end surface to connect the internal conductor film to the external circuit.

[0004]

FIG. 3 is a front sectional view of a chip-type electronic component of the type described above. An internal conductor film 31 constituting an element is formed on a surface of an insulating substrate 30 such as alumina.
Is formed, and this is covered with a protective layer 32 such as glass. A conductor film 36 of silver or the like is formed on the cut surface to form a terminal electrode,
Usually, a plating layer 37 of tin or the like is further formed.

However, at the time of division into individual elements, the shape of the glass protective layer 32 is not stable, so that it becomes difficult to apply silver for forming the external terminal electrodes 36 later,
Stress is concentrated at the time of soldering for mounting on a printed circuit board, causing problems such as cracking and peeling of terminal electrodes.
The stress due to the thermal shrinkage of the solder 41 causes cracks or peeling at the portions shown by the broken lines in FIG. Therefore, the connection between the internal conductor film and the conductor of the terminal electrode cannot be often made or becomes unstable.

[0006] The present invention solves the above problems,
Provided is a chip-type electronic component capable of preventing stress from being concentrated on a lead-out portion of an internal conductor film, providing good connection between the internal conductor film and a terminal electrode, and preventing peeling or the like due to soldering, and a method of manufacturing the same. Things.

[0007]

The present invention solves the above-mentioned problems by forming a portion where the internal conductor film is exposed at the end face so as to be inclined with respect to a cut surface.

That is, in a chip-type electronic component in which an internal conductive film is provided on the surface of an insulating substrate, the conductive film is covered with a protective layer made of an insulating material, and an end of the internal conductive film is drawn out to a cut surface. The feature is that a portion of the end surface from which the internal conductor film is drawn is inclined with respect to the cut surface.

In addition, an internal conductor film is formed on the surface of an insulating substrate, the internal conductor film is covered with a protective layer made of an insulating material, and the substrate is divided into individual elements to form terminal electrodes on each element. In a method of manufacturing a chip-type electronic component,
After covering the internal conductor film with the protective layer, a groove is formed from the protective layer to the insulating substrate, and then divided into respective elements at the groove portion, and a terminal electrode is formed on a cut surface including the groove portion. In particular, it has features.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The process of the method for manufacturing a chip-type electronic component according to the present invention is as follows. Formation of internal conductor film on substrate surface Formation of protective layer Formation of groove in cut section Cutting (division) Formation of terminal electrode on end face Plating if necessary

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front sectional view (a) and a plan view (b) showing an example of a chip-type electronic component according to the present invention. The structure is basically the same as that of the related art. An internal conductor film 11 is formed on the surface of an insulating substrate 10 such as alumina, and this is covered with a protective layer 12 such as glass. A conductor film 16 of silver or the like is formed on the cut surface to form a terminal electrode, and usually a plating layer of tin or the like.
17 are formed.

In the present invention, the end surface of the internal conductor film 11 where the conductor film is exposed is formed so as to be inclined with respect to the cut surface on which the terminal electrode is formed, as shown in the figure. The terminal electrode 16 is also formed on this portion, and the connection between the internal conductor film 11 and the terminal electrode 16 is performed.

Next, a method of manufacturing a chip-type electronic component according to the present invention will be described. FIG. 2 is a front sectional view showing the manufacturing method. A wafer is prepared in which an internal conductor film 21 and a protective layer 22 such as glass are formed on the surface of an insulating substrate 20 such as alumina (a). A groove 24 is formed from the front side of the wafer on which the protective layer 22 is formed. The groove 24 is formed by the protective film 22 and the internal conductor film.
It is formed so as to penetrate 21 and reach the substrate 20 (b).

The substrate is divided into individual elements at the grooves (c). Thereafter, a terminal electrode is formed, and the method may be a conventional method.

The shape of the groove can be arbitrarily set. However, in order to facilitate the division and stabilize the shape of the cut surface, the groove may be formed in a U-shape as shown in FIG.
It is good to make it letter-shaped. The depth is also arbitrary, but it is necessary that the depth is at least such that the internal conductor film 21 is exposed in the groove.

The present invention can be applied not only to passive components such as resistors, inductors and capacitors, but also to entire electronic components in which an internal conductor film is formed on the surface of a substrate and its end is connected to a terminal on the end surface.

[0018]

According to the present invention, it is possible to make the shape of the portion exposed to the end face of the internal conductor film constant when divided into elements. Therefore, external terminal electrodes can be reliably formed and connected to this portion.

Further, since stress due to the thermal shrinkage of the solder can be prevented from being concentrated on the end face portion where the internal conductor film is exposed, cracking and peeling of the terminal electrode can be easily prevented, and a highly reliable electronic component can be obtained. can get.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention.

FIG. 2 is a front sectional view showing an embodiment of the present invention.

3A and 3B are front sectional views and FIG. 3B is a plan view showing a conventional chip-type electronic component.

FIG. 4 is a partial perspective view showing a conventional chip-type electronic component.

[Explanation of symbols]

 10, 20, 30: Alumina substrate 11, 21, 31: Internal conductor film 12, 22, 32: Protective layer 24: Groove 16, 26: Terminal electrode 17, 27, 37: Solder plating layer

Claims (2)

[Claims] 1. A chip-type electronic component having an internal conductor film on a surface of an insulating substrate, wherein the internal conductor film is covered with a protective layer made of an insulating material, and an end of the internal conductor film is drawn out to a cut surface. 2. The chip-type electronic component according to claim 1, wherein a portion of the end surface from which the internal conductor film is drawn out is inclined with respect to the cut surface. 2. An internal conductor film is formed on a surface of an insulating substrate, the internal conductor film is covered with a protective layer made of an insulating material, and the substrate is divided into individual elements to form terminal electrodes on each element. In the method of manufacturing a chip-type electronic component, after covering the internal conductor film with a protective layer, a groove is formed from the protective layer to the insulating substrate, and then divided into respective elements at the groove portion. A method of manufacturing a chip-type electronic component, comprising forming a terminal electrode on a cut surface including the same.