Heating – Processes of heating or heater operation – Including passing – treating or conveying gas into or through...
Reexamination Certificate
2000-06-30
2002-04-23
Wilson, Gregory (Department: 3749)
Heating
Processes of heating or heater operation
Including passing, treating or conveying gas into or through...
C432S121000, C029S025420
Reexamination Certificate
active
06375457
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a multilayered ceramic electronic component, e.g., a multilayered ceramic capacitor; and, more particularly, to a method for manufacturing a multilayered ceramic electronic component using a laminated ceramic body.
BACKGROUND OF THE INVENTION
In manufacturing a multilayered ceramic electronic component using a laminated ceramic body, the laminated ceramic body is, generally, fired in a tunnel furnace.
In order to reduce the cost of electrode materials, internal electrodes made of a base metal such as Ni are commonly employed in multilayered ceramic electronic components. A firing process for such multilayered ceramic electronic components is therefore carried out in a reductive or a neutral atmosphere in order to prevent an increase of internal resistance due to, e.g., the oxidation of the internal electrodes and obtain desired characteristics of the multilayered ceramic components. For this reason, various tunnel furnaces for performing a firing process in a reductive or a neutral atmosphere have been developed. In such a tunnel furnace, unfired multilayered ceramic bodies are loaded thereinto using a pallet having multiple shelves on which the unfired multilayered ceramic bodies are placed.
However, when firing the multilayered ceramic bodies in the furnace, gaseous organic materials are generated from the ceramic bodies due to the heat of the furnace, which in turn causes local disturbance of the atmosphere of the furnace during the firing process, resulting in local firing non-uniformities in the fired ceramic bodies to occur depending on their locations in the furnace.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a method for manufacturing multilayered ceramic electronic components having reduced deviations in the electrical characteristics thereof. In accordance with the present invention, it becomes possible to maintain the stable atmosphere in the firing furnace without being affected by the gaseous products generated from the organic materials contained in the ceramic bodies being processed by the firing process. Accordingly, the firing non-uniformity problem of the prior art can be substantially ameliorated and the variation of the electrical characteristics of the resultant multilayered ceramic electronic component is substantially reduced.
In accordance with an embodiment of the present invention, there is provided a method for manufacturing a multilayered ceramic electronic component includes the step of firing multilayered ceramic bodies having therein ceramic layers and internal electrodes in a firing furnace while flowing one or more atmosphere gases thereinto, wherein the ratio of the amount of the atmosphere gases introduced into the firing furnace per a time period to the amount of organic materials included in the multilayered ceramic bodies introduced into the firing furnace per the time period is between about 200 L/g and about 1200 L/g and the multilayered ceramic bodies are introduced into the firing furnace along a first direction and the atmosphere gases flow in the firing furnace along a direction opposite to the first direction.
REFERENCES:
patent: 4177035 (1979-12-01), Buschermohle
patent: 5046946 (1991-09-01), Yasuda et al.
patent: 5101319 (1992-03-01), Diffeyes et al.
patent: 5230846 (1993-07-01), Tamhankar et al.
patent: 5735027 (1998-04-01), Hageman et al.
Rosenman & Colin LLP
Taiyo Yuden Co. Ltd.
Wilson Gregory
LandOfFree
Method for manufacturing a multilayered ceramic electronic... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for manufacturing a multilayered ceramic electronic..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for manufacturing a multilayered ceramic electronic... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2830121