CN-115602445-B - Multilayer capacitor

Abstract

The present disclosure provides a multilayer capacitor including a capacitor body, a first external electrode, and a second external electrode. The capacitor body includes a plurality of first internal electrodes and a plurality of second internal electrodes alternately stacked with a dielectric layer interposed therebetween. The first and second external electrodes are electrically connected to the plurality of first and second internal electrodes, respectively. A first schottky layer schottky junction is to an interface between the dielectric layer and the first inner electrode in the capacitor body. A second schottky layer schottky junction is coupled to an interface between the dielectric layer and the second inner electrode in the capacitor body. The work function values of the first Schottky layer and the second Schottky layer are higher than the work function values of the first internal electrode and the second internal electrode.

Inventors

• QIAN ZHENCHENG
• Ding Haishuo
• JIN JINGJUN
• JIANG BINGCHENG

Assignees

• 三星电机株式会社

Dates

Publication Date

20260508

Application Date

20181212

Priority Date

20180719

Claims (15)

1. 1. A multilayer capacitor, the multilayer capacitor comprising: A capacitor body including a plurality of first internal electrodes and a plurality of second internal electrodes alternately stacked with a dielectric layer interposed therebetween; First and second external electrodes electrically connected to the plurality of first and second internal electrodes, respectively; a first Schottky layer at the interface between the first internal electrode and the dielectric layer, and A second Schottky layer at the interface between the second internal electrode and the dielectric layer, Wherein the first work function value of the first Schottky layer and the second work function value of the second Schottky layer are higher than the third work function value of the first inner electrode and the second inner electrode, the third work function value of the first inner electrode and the second inner electrode is higher than the fourth work function value of the dielectric layer, and Wherein the capacitor body comprises a repeating stacked structure comprising, in order, one of the dielectric layers, one of the plurality of first internal electrodes, one of the plurality of first schottky layers, another of the dielectric layers, one of the plurality of second internal electrodes, and one of the plurality of second schottky layers.
2. 2. The multilayer capacitor of claim 1, wherein the first schottky layer is located on only one of an upper surface and a lower surface of the first internal electrode in the stacking direction of the dielectric layer, and the second schottky layer is located on only one of an upper surface and a lower surface of the second internal electrode in the stacking direction.
3. 3. The multilayer capacitor of claim 2, wherein the first schottky layer covers the entire one surface of the first internal electrode and the second schottky layer covers the entire one surface of the second internal electrode.
4. 4. The multilayer capacitor of claim 1, wherein the first schottky layer is located on a lower surface of the first internal electrode in the stacking direction of the dielectric layer, and the second schottky layer is located on a lower surface of the second internal electrode in the stacking direction.
5. 5. The multilayer capacitor of claim 4 wherein the first schottky layer covers the entire lower surface of the first inner electrode and the second schottky layer covers the entire lower surface of the second inner electrode.
6. 6. The multilayer capacitor of claim 1, wherein the first and second schottky layers are insulating semiconductor layers.
7. 7. The multilayer capacitor of claim 6, wherein the insulating semiconductor layer comprises at least one of molybdenum disulfide, molybdenum oxide, tungsten diselenide, cadmium telluride, and cadmium sulfide.
8. 8. The multilayer capacitor of claim 1, wherein the dielectric layer comprises barium titanate.
9. 9. The multilayer capacitor of claim 1, wherein the first and second internal electrodes comprise one or more of platinum, palladium-silver alloy, nickel, and copper.
10. 10. The multilayer capacitor of claim 1, wherein a first dimension of the upper or lower surface of the first schottky layer and a second dimension of the upper or lower surface of the second schottky layer are each equal to or greater than a third dimension of the upper or lower surface of the first or second internal electrode.
11. 11. The multilayer capacitor according to claim 1, wherein the capacitor body includes a first surface and a second surface opposite to each other in a stacking direction, a third surface and a fourth surface connected to the first surface and the second surface and opposite to each other in a length direction substantially perpendicular to the stacking direction, and a fifth surface and a sixth surface connected to the first surface and the second surface and connected to the third surface and the fourth surface and opposite to each other in a width direction substantially perpendicular to the stacking direction and the length direction, Wherein the length of the capacitor body in the length direction is larger than the width of the capacitor body in the width direction, and Wherein the first and second internal electrodes are exposed to the third and fourth surfaces, respectively.
12. 12. The multilayer capacitor of claim 11, wherein the first and second schottky layers are exposed to the third and fourth surfaces of the capacitor body, respectively.
13. 13. A multilayer capacitor, the multilayer capacitor comprising: An effective region including a plurality of first internal electrodes and a plurality of second internal electrodes, a plurality of dielectric layers, and a plurality of schottky layers interposed between the plurality of dielectric layers and the internal electrodes, respectively, the internal electrodes including the plurality of first internal electrodes and the plurality of second internal electrodes; an upper cover including one or more dielectric layers located above an upper surface of the active region in a stacking direction; a lower cover including one or more dielectric layers located below a lower surface of the active region in the stacking direction; a first external electrode connection part located on a first side surface of the active region, the upper and lower covers substantially parallel to the stacking direction and electrically connected to the first internal electrode; A second external electrode connection part which is located on a second side surface of the effective region, the upper cover and the lower cover, which is substantially parallel to the stacking direction and opposite to the first side surface, and which is electrically connected to the second internal electrode, Wherein the Schottky layer has a first work function value, the plurality of first internal electrodes and the plurality of second internal electrodes have a second work function value, the plurality of dielectric layers have a third work function value, the first work function value is greater than the second work function value, and the second work function value is greater than the third work function value, Wherein the active region comprises a repeating stack structure comprising, in order, one of the dielectric layers, one of the plurality of first internal electrodes, one of the plurality of schottky layers, another of the dielectric layers, one of the plurality of second internal electrodes, and another of the plurality of schottky layers.
14. 14. The multilayer capacitor of claim 13, wherein the plurality of schottky layers comprise at least one of molybdenum disulfide, molybdenum oxide, tungsten diselenide, cadmium telluride, and cadmium sulfide.
15. 15. The multilayer capacitor of claim 13, wherein the plurality of schottky layers have respective first regions perpendicular to the stacking direction that are equal to or greater than respective second regions perpendicular to the stacking direction of the plurality of first internal electrodes and the plurality of second internal electrodes.

Description

Multilayer capacitor The application is a divisional application of an application patent application with the application date of 2018, 12 months and 12 days, the application number of 201811516709.1 and the application name of multilayer capacitor. Technical Field The present disclosure relates to a multilayer capacitor. Background Multilayer capacitors are conventional passive components and include dielectric layers, inner electrodes, and outer electrodes. Recently, multilayer capacitors are required to increase capacitance while maintaining the same size as existing multilayer capacitors, and to have thinned dielectric layers and internal electrodes, atomized dielectric particles, and the like. For example, in recent high-end products, in order to increase the capacitance of a multilayer capacitor, dielectric layers and internal electrodes are laminated in an amount of hundreds of layers, and high capacitance is achieved by high integration using dielectric layers having a thickness of 1 μm or less. However, the thinning and fogging of the dielectric layer increases the insulation resistance. The thinned and atomized dielectric layer increases the risk of electrical shorting when two inner electrodes adjacent to each other are in contact. This may degrade the reliability of the multilayer capacitor. Disclosure of Invention An aspect of the present disclosure provides a multilayer capacitor having reduced risk of electrical shorting occurring when two adjacent internal electrodes are in contact, and simultaneously reduced thickness of dielectric layers and thickness of internal electrodes, thereby improving capacitance and reliability of a product. According to an aspect of the present disclosure, a multilayer capacitor includes a capacitor body, a first external electrode, and a second external electrode. The capacitor body includes a plurality of first internal electrodes and a plurality of second internal electrodes alternately stacked with a dielectric layer interposed therebetween. The first and second external electrodes are electrically connected to the plurality of first and second internal electrodes, respectively. A first schottky layer is located at a respective interface between the dielectric layer and the first internal electrode. A second schottky layer is located at a respective interface between the dielectric layer and the second internal electrode. The work function values of the first Schottky layer and the second Schottky layer are higher than the work function values of the first internal electrode and the second internal electrode. In an exemplary embodiment of the present disclosure, the first schottky layer may be formed on only one of the surfaces of the first internal electrode, and the second schottky layer may also be formed on only one of the surfaces of the second internal electrode. In an exemplary embodiment of the present disclosure, the capacitor body may be formed by repeating a stacked structure in which a dielectric layer, a first internal electrode, a first schottky layer, another dielectric layer, a second internal electrode, and a second schottky layer are laminated. In an exemplary embodiment of the present disclosure, the capacitor body may be formed by repeating a stacked structure in which a dielectric layer, a first schottky layer, a first internal electrode, another dielectric layer, a second schottky layer, and a second internal electrode are laminated. In an exemplary embodiment of the present disclosure, the first schottky layer may cover the entire one surface of the first internal electrode, and the second schottky layer may cover the entire one surface of the second internal electrode. In example embodiments of the present disclosure, the first schottky layer may be formed on both upper and lower surfaces of the first internal electrode, and the second schottky layer may be formed on both upper and lower surfaces of the second internal electrode. In example embodiments of the present disclosure, the first schottky layer may cover the entire upper surface and the entire lower surface of the first internal electrode, respectively, and the second schottky layer may cover the entire upper surface and the entire lower surface of the second internal electrode, respectively. In an exemplary embodiment of the present disclosure, the capacitor body may be formed by repeating a stacked structure in which a dielectric layer, a first schottky layer, a first internal electrode, another first schottky layer, another dielectric layer, a second schottky layer, a second internal electrode, and another second schottky layer are laminated. In an exemplary embodiment of the present disclosure, the first schottky layer and the second schottky layer may be insulating semiconductor layers. In exemplary embodiments of the present disclosure, the insulating semiconductor layer may include at least one of molybdenum disulfide (MoS 2), molybdenum oxide (MoO x), tungsten diselen