JPS626675Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the electrode formation and structure of a chip-type semiconductor ceramic capacitor, and its purpose is to manufacture an inexpensive high-capacitance semiconductor ceramic capacitor using lead wires. directly without
It is intended to be attached to a printed circuit board and fixed by soldering. With the development of IC circuits, the demand for inexpensive, large-capacity, and ultra-small capacitors has increased, but there has been no capacitor that satisfies all of these requirements. Conventionally, as a capacitor for hybrid IC circuits,
There is a multilayer capacitor 1 as shown in FIG.
The use of expensive precious metals, large amounts of laminated electrodes, and the manufacturing process, which is complex and extremely costly, has hindered the use of laminated capacitors.

The present invention focuses on a grain boundary layer type semiconductor capacitor in which only the grain boundary layer of semiconductor porcelain whose main component is barium titanate or strontium titanate is insulated, and attempts to fabricate this into a chip. Further, the present invention can also be applied to a surface layer type semiconductor ceramic capacitor in which only the surface layer of semiconductor ceramic is insulated.

An embodiment of the chip type semiconductor ceramic capacitor of the present invention will be described below. In Figure 2, 2
is a chip type semiconductor ceramic capacitor, and the element body 3
uses a grain boundary layer type semiconductor in which only the grain boundary layer of semiconductor porcelain whose main component is barium titanate or strontium titanate is insulated. On the surface of this rectangular parallelepiped element 3, there is one electrode 4 which covers most of the upper surface, one side surface, and most of the lower surface and has a U-shaped cross section and is composed of an upper surface portion 4a, a side surface portion 4b, and a lower surface portion 4c.
is attached, and has a cross section approximately T having an extension portion 9 that covers the side surface opposite to the above-mentioned one side surface, and a small portion of the upper surface and the lower surface, and deeply penetrates into the interior of the element body 3.
A letter-shaped other electrode 5 is provided. Gaps 6, 7, and 8 are formed at a certain distance between the one electrode 4 and the other electrode 5, and the extending portion 9 of the other electrode 5 is after the thickness of the element body 3. The upper and lower surfaces of one electrode 4, which is located at the center of the electrode 4, are equally spaced from each other. Therefore, a correct capacitor with no error in capacitance value can be obtained.

To attach this capacitor 2 to a board, as shown in FIG.
After placing the capacitor 2 on the capacitor 12 so that the electrodes 4 and 5 are in contact with each other, the capacitor 2 may be connected using solders 13 and 14. Since the electrodes 4 and 5 cover most of the surface of the element body 3, the soldering work is extremely easy. The electrodes 4 and 5 described above cover almost the entire surface of the element body 3, and in the chip-type semiconductor ceramic capacitor provided with the extension part 9, the opposing area of the electrodes 4 and 5 is large, and the distance between them is small. Because it was possible to shorten the capacitance, the capacitance was nearly twice as high as that of conventional semiconductor ceramic capacitors.

As described above, according to the present invention, high capacity can be obtained,
It can be soldered directly and firmly to the printed circuit board without using lead wires, and has the advantage of being inexpensive.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional chip-type multilayer ceramic capacitor, FIG. 2 is a perspective view of a chip-type semiconductor ceramic capacitor according to an embodiment of the present invention, and FIG. 3 is a sectional side view of the same. 2... Chip type semiconductor ceramic capacitor, 3...
Element body, 4, 5... Electrode, 6, 7, 8... Gap, 9... Extension part, 10... Printed circuit board, 1
1, 12... Conductive foil, 13, 14... Solder.

Claims (1)

[Claims for Utility Model Registration] (1) Covering most of the upper and lower surfaces and one side of a semiconductor porcelain whose only grain boundary layer or surface layer is insulated, it consists of an upper surface portion 4a, a side surface portion 4b, and a lower surface portion 4c. A first electrode 4 having a U-shaped cross section is provided, and is located within the semiconductor ceramic and covers the one side surface, the other side surface opposite to the semiconductor ceramic, and a small portion of the top surface and the bottom surface, and is located within the semiconductor ceramic. A second electrode 5 having an extending portion 9 that is parallel to the upper surface portion 4a and the lower surface portion 4c of the electrode 4, is sufficiently long, and does not reach the side surface portion 4b of the first electrode.
Chip type semiconductor porcelain capacitor. (2) The chip-type semiconductor ceramic capacitor according to claim 1, which is made of semiconductor ceramic whose main component is barium titanate or strontium titanate. (3) The distance between the upper surface portion 4a of the first electrode 4 and the extension portion 9 of the second electrode 5, and the distance between the lower surface portion 4c of the first electrode and the extension portion 9 of the second electrode 5. A chip-type semiconductor ceramic capacitor according to claim 1 of the utility model registration claim, in which the spacing between and is equal to each other.