JP3018644B2 - Chip composite function device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip composite function device having a structure in which a capacitor and a resistor are connected in series.

[0002]

2. Description of the Related Art In recent years, as electronic devices have become lighter and thinner, there has been a demand for smaller, thinner, and more surface-mounted circuit elements, and the demand for chip components such as chip resistors and chip capacitors has been increasing. The demand for a chip composite function element in which a capacitor and a resistor are connected in series is also increasing. Heretofore, a chip composite device in which a capacitor and a resistor are connected in series has not been put to practical use, and a device in which a thick film resistor and a thick film dielectric are formed in series on an insulating substrate such as alumina has been considered.

Hereinafter, a conventional chip composite device in which a thick film resistor and a thick film dielectric are formed in series on an alumina substrate will be described.

FIG. 2 is a cross-sectional view of a conventional chip composite function element in which a thick film resistor and a thick film dielectric are formed in series on an alumina substrate. In FIG. 2, reference numeral 1 denotes a rectangular insulating substrate made of alumina or the like. 2 and 3 are primary electrodes,
It is formed on both ends of the insulating substrate 1. Reference numeral 4 denotes an intermediate electrode, which is provided between the primary electrodes 2 and 3. Reference numeral 5 denotes a thick-film resistor, which is formed between the primary electrode 2 and the intermediate electrode 4. Reference numeral 6 denotes a thick-film dielectric, which is provided on the intermediate electrode 4 so as to partially overlap each other. Reference numeral 7 denotes an upper electrode formed on the thick film dielectric 6 and connected to the primary electrode 3.
Reference numeral 8 denotes crystallized glass, which covers the thick film dielectric 6. Reference numeral 9 denotes an amorphous glass which covers the thick film resistor 5 and the thick film dielectric 6. Reference numeral 10 denotes a terminal electrode, which is connected to the primary electrodes 2 and 3. 11
Denotes a terminal electrode plating layer that covers the primary electrodes 2 and 3 and the terminal electrode 10. Generally, a capacitor made of a thick film dielectric is
To ensure reliability, a double coat of such crystallized glass and amorphous glass is used.

[0005]

However, in the chip composite function device constructed as described above, when the flowability of the amorphous glass 9 is poor, a gap is formed between the primary electrodes 2 and 3 and plating occurs. Sometimes two or three primary electrodes and amorphous glass 9
The plating solution infiltrates from the interface with the substrate and passes through the crystallized glass 8 having many voids to reach the thick film capacitor, thereby deteriorating the insulating properties, or forming a thin groove between the terminal electrode 10 and the amorphous glass 9 to form a thin groove. There is a problem that the plating solution cannot be completely removed in the washing step after plating and the reliability is reduced.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a highly-reliable chip multifunction device which prevents deterioration of insulation during a plating process.

[0007]

In order to achieve the above object, a chip composite function device according to the present invention comprises a rectangular insulating substrate,
A pair of primary electrodes formed at opposite ends on the insulating substrate, an intermediate electrode formed between the primary electrodes at both ends, a thick-film dielectric formed on the intermediate electrode, An upper electrode formed on the film dielectric so as to be connected to one of the primary electrodes, a thick film resistor formed between the intermediate electrode and the other primary electrode, and covering the dielectric. The insulating substrate having crystallized glass, amorphous glass covering the crystallized glass and the resistor, and completely covering the exposed primary electrode and the interface between the amorphous glass and the primary electrode. Are provided with terminal electrodes on the side surfaces thereof.

[0008]

According to the structure of the present invention, a highly reliable chip composite function element in which the infiltration of the plating solution in the plating step is prevented and the deterioration of the insulating property is suppressed can be obtained.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a multifunctional chip according to an embodiment of the present invention. FIG. 1 is a sectional view of a chip multifunction device according to the present embodiment of the present invention. In FIG. 1, 1 is an insulating substrate such as alumina, 12 and 13 are primary electrodes formed at opposite ends of the insulating substrate 11, and 14 is a primary electrode 12 on the insulating substrate 11.
An intermediate electrode provided between the first and second electrodes; a thick film resistor connected between the primary electrode and the intermediate electrode; a thick film dielectric formed on the intermediate electrode so as to partially overlap each other; Is an upper electrode provided on the thick-film dielectric 16 so as to be connected to the primary electrode 13, 18 is crystallized glass covering the dielectric 16, and 19 is a non-crystallized glass covering the crystallized glass 18 and the thick-film resistor 15. Amorphous glass, 20 is a terminal electrode, and 21 is a plating layer formed on the terminal electrode. Terminal electrode 20
Are formed on the side surfaces of the insulating substrate 1 so as to completely cover the exposed portions of the primary electrodes 12 and 13 and to cover the interface between the amorphous glass 19 and the primary electrodes 12 and 13.

[0010] In the chip composite function device constructed as described above, the interface between the amorphous glass 20 and the primary electrodes 12 and 13 is completely covered by the terminal electrode 20, so that the intrusion of the plating solution during plating is suppressed. This can prevent the insulation of the thick film dielectric 16 from deteriorating.

[0011]

As described above, according to the present invention, by covering the interface between the primary electrode and the amorphous glass and the primary electrode with the terminal electrode, the infiltration of the plating solution during plating is prevented and the insulation of the capacitor is improved. A highly reliable chip composite function element that does not deteriorate can be realized.

[Brief description of the drawings]

FIG. 1 is a sectional view of a chip multifunction device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a conventional chip multifunction device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating substrate 12 Primary electrode 13 Primary electrode 14 Intermediate electrode 15 Thick film resistor 16 Thick film dielectric 17 Upper electrode 18 Crystallized glass 19 Amorphous glass 20 Terminal electrode 21 Plating layer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01G 4/14-4/42

Claims (1)

(57) [Claims] 1. A square insulating substrate, a pair of primary electrodes formed at opposite ends on the insulating substrate, an intermediate electrode formed between the primary electrodes at both ends, and A formed thick film dielectric, an upper electrode formed on the thick film dielectric to be connected to one of the primary electrodes, and formed between the intermediate electrode and the other primary electrode. A thick-film resistor, a crystallized glass covering the dielectric, an amorphous glass covering the crystallized glass and the resistor, and an exposed primary electrode and the amorphous glass A chip multifunction device having terminal electrodes provided on side surfaces of the insulating substrate so as to completely cover an interface with the electrodes.