News Column

Patent Issued for Electronic Component Including Multilayer Substrate

August 27, 2014



By a News Reporter-Staff News Editor at Journal of Engineering -- According to news reporting originating from Alexandria, Virginia, by VerticalNews journalists, a patent by the inventor Tanaka, Koji (Kyoto-fu, JP), filed on October 11, 2012, was published online on August 12, 2014.

The assignee for this patent, patent number 8802995, is Murata Manufacturing Co., Ltd (Kyoto-Fu, JP).

Reporters obtained the following quote from the background information supplied by the inventors: "Hitherto, various electronic components including a multilayer substrate in which a conductor pattern is disposed between dielectric layers have been proposed. For example, in a high-frequency module disclosed in Patent Document 1, a ground electrode 244 is formed, as shown in the plan view of FIG. 5, on substantially the entire surface of a dielectric layer 218 disposed within a multilayer substrate."

In addition to obtaining background information on this patent, VerticalNews editors also obtained the inventor's summary information for this patent: "Technical Problem

"In a multilayer substrate, dielectric layers and conductor patterns disposed between the dielectric layers are made of different materials. Accordingly, although the dielectric layers and the conductor patterns are in close contact with each other, a bonding force therebetween is weaker than that between the dielectric layers made of the same material. In particular, if a conductor pattern, which forms a ground electrode, is disposed in a wide range of a dielectric layer, a portion having a weak bonding force is continuously formed, thereby increasing the possibility of cracking or delamination occurring in the vicinity of interfaces between the dielectric layers and the conductor pattern.

"In view of the above-described background, the present invention provides an electronic component including a multilayer substrate which can prevent the occurrence of cracking or delamination in the vicinity of interfaces between a conductor pattern and dielectric layers even if the conductor pattern is disposed in a wide range of the dielectric layer.

"Solution to Problem

"In order to solve the above-described problem, the present invention provides an electronic component including a multilayer substrate configured as follows.

"The multilayer substrate of the electronic component includes: (a) a plurality of dielectric layers stacked on one another; (b) a first conductor pattern which is disposed along principal surfaces of the dielectric layers and which is electrically connected to a ground; and a second conductor pattern which is disposed along the principal surfaces of the dielectric layers and which opposes is opposed to the first conductor pattern with only through the dielectric layers therebetween, the second conductor pattern forming an inductor element, a stripline, or a microstrip line, which is electrically connected to an element other than a ground. An opening is formed in the first conductor pattern, and only the dielectric layers that sandwich the first conductor pattern therebetween in a stacking direction of the dielectric layers are bonded to each other via the opening. As viewed from the stacking direction in which the dielectric layers are stacked, the second conductor pattern substantially entirely overlaps a portion other than the opening in the first conductor.

"With the above-described configuration, even if the first conductor pattern is disposed in a wide range of a dielectric layer, the dielectric layers that sandwich the first conductor pattern therebetween are bonded to each other via the opening formed in the first conductor pattern, thereby strengthening a bonding force between the layers. That is, a bonding force between the dielectric layers is stronger than that between the dielectric layer and the first conductor pattern.

"With the above-described configuration, by forming the opening in the first conductor pattern, it is possible to avoid the continuous presence of the portions having a weak bonding force in which the dielectric layers and the first conductor pattern are in contact with each other. As a result, the occurrence of cracking or delamination in the vicinity of interfaces between the dielectric layers and the first conductor pattern can be prevented.

"Additionally, the second conductor pattern is entirely opposed to the first conductor pattern, which is electrically connected to a ground, only through the dielectric layers therebetween. Accordingly, the addition of the openings to the first conductor pattern does not influence the constant values (the inductances, etc.) of an inductor element formed by the second conductor pattern.

"Preferably, the second conductor pattern may include an electrode for a capacitor element.

"In this case, the addition of the opening to the first conductor pattern does not influence the constant values (the capacitances, etc.) of the capacitor element included in the second conductor pattern.

"Preferably, as viewed from the stacking direction, the first conductor pattern may be disposed at an inner portion of the dielectric layer so that spacing is formed all around the first conductor pattern between the first conductor pattern and an outer periphery of the dielectric layer adjacent to the first conductor pattern.

"In this case, the outer peripheral region of the dielectric layer adjacent to the first conductor pattern extends in a ring-like shape outside the first conductor pattern. The entire periphery of a portion having a relatively weak bonding force between the dielectric layer and the first conductor pattern is surrounded by a portion having a relatively strong bonding force between the peripheral regions of the dielectric layers that sandwich the first conductor pattern therebetween. Thus, a bonding force between the dielectric layers that sandwich the first conductor pattern therebetween is further strengthened. Additionally, a portion having a relatively weak bonding force between the first conductor pattern and the dielectric layers is not exposed from the side surfaces of the multilayer substrate, thereby making it possible to prevent the occurrence of interlayer cracking or delamination between the layers due to the impact from an external source.

"Preferably, the first conductor pattern may be disposed on a portion which occupies 80% or higher of an area of the principal surface of the dielectric layer adjacent to the first conductor pattern.

"If the first conductor pattern is disposed on substantially the entirety of the principal surface of the dielectric layer, the effect of strengthening a bonding force between the layers by forming the opening in the first conductor pattern becomes more noticeable.

"Preferably, the dielectric layers may be made of low temperature co-fired ceramics.

"In this case, when fabricating the multilayer substrate of the electronic component by using low temperature co-fired ceramics, by adjusting the shape, size, position, and number of the openings formed in the first conductor pattern, warpage of the multilayer substrate caused by a temperature change during firing can be reduced.

"Advantageous Effects of Invention

"In an electronic component including a multilayer substrate of the present invention, it is possible to prevent the occurrence of cracking or delamination in the vicinity of interfaces between a conductor pattern and dielectric layers even if the conductor pattern is disposed in a wide range of the dielectric layer."

For more information, see this patent: Tanaka, Koji. Electronic Component Including Multilayer Substrate. U.S. Patent Number 8802995, filed October 11, 2012, and published online on August 12, 2014. Patent URL: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=8802995.PN.&OS=PN/8802995RS=PN/8802995

Keywords for this news article include: Murata Manufacturing Co. Ltd.

Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC


For more stories covering the world of technology, please see HispanicBusiness' Tech Channel



Source: Journal of Engineering


Story Tools






HispanicBusiness.com Facebook Linkedin Twitter RSS Feed Email Alerts & Newsletters