KR20060095390A - Plate-type ceramic heater - Google Patents

Abstract

The present invention relates to a ceramic heater, which generates heat by heating a resistance heating element on both sides of a ceramic support constituting the ceramic heater and improving the wiring method of the resistance heating element so that the heating element patterns are interconnected through via holes formed in the support. To rise on both sides of the In addition, by stacking two or more layers of the ceramic support printed on one surface of the resistance heating element and interconnecting the resistance heating elements of each layer through the via hole formed in the ceramic support, the amount of heat generated is increased without increasing the area of the ceramic heater. By adopting such a wiring method, not only the amount of heat generated by the ceramic heater can be increased, but also heat can be generated uniformly in the entire area of the heater. In addition, by using a ledge hole formed in the ceramic support can reduce the alignment error during the stacking it is possible to increase the mass productivity of the ceramic heater.

Ceramic Heater, Lamination, Via Hole, Green Sheet, Simultaneous Firing, Metal Pattern

Description

Plate-shaped Ceramic Heater {PLATE-TYPE CERAMIC HEATER}

Figure 1a is a metal resistor pattern formed on the front surface of the ceramic green sheet support.

Figure 1b is a metal resistor pattern formed on the back of the ceramic green sheet support.

Figure 2 is a detailed view showing a method for laminating a ceramic protective layer on the front and back of the ceramic green sheet support on which the metal resistor pattern is formed.

3A is a sectional view of a laminated plate ceramic heater;

3B is a detailed view illustrating a method of connecting a metal resistor pattern to via holes formed in a ceramic green sheet.

4 is a detailed view showing a method of laminating a ceramic support and a ceramic protective layer on which a metal resistor pattern is single-sided printed.

FIG. 5A is a planar metal resistor pattern corresponding to the second layer in the laminate of FIG. 4. FIG.

FIG. 5B is a planar metal resistor pattern corresponding to the third layer in the laminate of FIG. 4. FIG.

FIG. 5C is a planar metal resistor pattern corresponding to the fourth layer in the laminate of FIG. 4. FIG.

6 is a cross-sectional view of a laminated plate-shaped ceramic heater laminated by the method of FIG. 4.

*** Explanation of symbols for main parts of drawing ***

10: ceramic support 11: ceramic protective layer

12: Resident Hall 14: Beer Hall

16a, 16b: metal resistor patterns 20a, 20b, 20c: ceramic support

21: ceramic protective layer 22: resist hole

24: Beer hole 26a, 26b, 26c: Metal resistor pattern

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate-shaped ceramic heater, and more particularly, to a multilayer ceramic heater in which an amount of a metal resistor pattern is increased to improve heat generation characteristics.

Representative examples of the heaters include metal heating elements, silicon carbide heating elements, molybdenum silicide heating elements, and ceramic heating elements. As a metal heating element, nichrome wire, iron chromium wire, and cantal wire (Fe-Cr-Al) of relatively low price are used. Although such a heating element may be used while being removed, when used in an open atmosphere, it is enclosed in an insulating ingredient powder (for example, stainless steel) to prevent deterioration of the atmosphere. In this case, the heat resistance temperature is also determined according to the stainless pipe, and the maximum temperature is about 800 ° C. Nevertheless, products of this configuration are quite expensive. In addition, although platinum wire is used by being expensive, this is limited to the case where the system to be used is special. The most representative of the high-temperature heating element is a silicon carbide heating element, which can be used continuously in the air at 1400 ° C. for a necessary time, and is widely used as a heating element for high-temperature electric furnaces instead of metal heating elements other than metals. However, the major drawback of this heating element is that the temperature coefficient of the temperature characteristic of the resistance changes rapidly from minus 800 ° C to 1000 ° C, and it is necessary to examine the control circuit sufficiently, and the control circuit is included. This is expensive. After all, it is rarely used as a general-purpose heating element. In recent years, molybdenum silicide has been developed as a heating element for high temperature, but it is very expensive and has a kind of glass phase, so that its mechanical strength is weak, and it is only applied as a heater of a special electric furnace. The above-described silicon carbide heating element is also not very good in mechanical strength.

Next, as the latest heating element, a tungsten metal is put on an insulating alumina substrate and the whole is coated with alumina. This is known as a ceramic heater, but when used at a temperature of 1000 ° C or higher, there is a problem in that the internal tungsten is oxidized and the resistance thereof is changed, and eventually it is used as 800 ° C or lower. This ceramic heater is most expected because it is likely to be manufactured to be comparable to cheap metal heating elements.

The ceramic heater has a general structure including an insulating ceramic support, a metal resistance heating element pattern, and a protective layer protecting the same. Tungsten or molybdenum are generally used as a heating element metal in such a ceramic heater, and nitride ceramics or oxide ceramics are widely used as a ceramic protective layer protecting a ceramic support and a metal pattern. Tungsten is used as a metal, and alumina excellent in high temperature durability is most used as a ceramic support and a protective layer.

Ceramic heaters are manufactured in the form of rods, tubes, plates, etc., depending on the intended use.In the case of rods or plates, the metal resistor pattern constituting the heating portion of the ceramic heater is mainly printed on the ceramic layer protecting the heating element. It is then rolled and laminated on rod-shaped and tubular ceramic supports, followed by sintering it. In this case, a method of manufacturing a rod-like and tube-like support using alumina and then laminating a sheet-like protective layer on which a metal resistor pattern is printed is applied, so that the ceramic protective layer is laminated on the support by applying a uniform force because the shape of the support is curved. Since it is difficult to do so, there is a problem that a great deal of delamination of the protective layer occurs in the process of sintering the ceramic heater having the protective layer laminated thereon. Therefore, the trend of manufacturing the shape of the ceramic heater in the form of a plate has been adopted in recent years due to the manufacturing efficiency, except for the use of a rod-shaped and tube-shaped ceramic heater.

In the case of manufacturing a ceramic heater in the form of a plate, unlike a rod or tube, it is possible to directly print a metal pattern on a ceramic support, and in the sintering process, it is possible to apply a uniform force when laminating a protective layer protecting the same. There is an advantage that can reduce the defective rate of. However, most of the plate-shaped ceramic heaters produced so far have a problem in that a resistor pattern is printed using only one side of the ceramic support, and heat generation is not uniform throughout the heating element, such as a rod-like or tube-shaped heating element. In addition, when the metal resistor pattern is widened in order to increase the amount of heat generated, the area of the ceramic support becomes large, so that the problem of weakening due to the characteristics of the ceramic product may not be avoided.

Therefore, an object of the present invention is to improve the heat generating characteristics of the ceramic heater. Specifically, an object of the present invention is to increase the amount of heat generated by changing the wiring structure of the metal baton of the ceramic heater.

In addition, another object of the present invention is to provide a ceramic heater having improved durability while increasing the heating pattern by increasing the metal pattern without increasing the area of the ceramic support.

In addition, another object of the present invention to provide a ceramic heater of a new structure that can increase the manufacturing yield while the ceramic heater manufacturing process is simple.

Other objects and features of the present invention will be presented in more detail below.

In order to achieve the above object, the present invention is a ceramic having a plurality of metal patterns are formed on the upper and lower surfaces, the upper and lower metal patterns are interconnected by via holes and at least one resist hole formed at the edge Sheets; The present invention provides a plate-shaped ceramic heater stacked on top and bottom surfaces of the ceramic sheet and including a ceramic protective layer including at least one resist hole.

The metal patterns formed on the upper and lower surfaces of the ceramic sheet may be designed so as not to cross vertically except for portions interconnected by via holes.

In addition, in the present invention, a plurality of ceramic sheets has a plurality of metal patterns formed on one surface thereof, and each of the ceramic sheets has a via hole interconnecting the metal patterns, and at least one resist hole formed at an edge thereof. A ceramic laminate in which each ceramic sheet is aligned and stacked around the ceramic laminate; The present invention provides a plate-shaped ceramic heater stacked on one surface of the ceramic laminate and including a ceramic protective layer including at least one resist hole.

The metal pattern formed on one surface of each ceramic sheet is preferably designed not to cross vertically except portions interconnected by via holes.

According to a first aspect of the present invention, by printing a resistance heating element on both sides of a ceramic support constituting a ceramic heater and improving the wiring method of the resistance heating element so that the heating element patterns are interconnected through via holes formed in the support. Allow heat to occur on both sides of the ceramic heater. According to a second aspect of the present invention, an area of a ceramic heater is formed by stacking two or more layers of a ceramic support printed on at least one surface of a resistance heating element and interconnecting the resistance heating elements of each layer through via holes formed in the ceramic support. Allow heat to increase without widening.

By adopting such a wiring method, not only the amount of heat generated by the ceramic heater can be increased, but also heat can be generated uniformly in the entire area of the heater. In addition, in the manufacturing process, the same metal heating element pattern can be simultaneously formed on the green sheet for the ceramic support by one printing process, and the alignment error during lamination can be reduced by using the resist hole formed in the ceramic support, thereby achieving mass productivity of the ceramic heater. Can increase.

Hereinafter, the present invention will be described in more detail with reference to specific examples. In the following examples, a ceramic heater and a technique related to the production thereof, for example, a raw material such as a high melting point metal powder, a ceramic raw material powder, a binder, a solvent, or a raw material such as a paste or dry powder Well-known contents such as mixing, dispersing, printing, sintering, and the like are not explicitly described.

1A and 1B illustrate a plurality of metal resistor (or heating element) patterns 16a and 16b formed on the front and back surfaces of the ceramic support 10 green sheet according to the first embodiment of the present invention.

The metal resistor pattern 16a printed on one surface may be interconnected by the metal resistor pattern 16b and the via hole 14 on the other surface. A ledge hole 12 is formed near the edge of the ceramic support 10, which is easily aligned when a protective layer (not shown) deposited on the upper or lower surface of the ceramic support 10 is stacked. do. The metal resistor pattern may be formed in various ways, and a screen printing method may be used.

The via hole used to connect the metal resistor pattern of the ceramic support and the resist hole used to deposit the protective layer of the ceramic bark may be formed using a punching machine. For filling the via holes, a screen printing method used for printing a metal resistor pattern may be used.

The plurality of metal resistor patterns 16a and 16b formed on the front and rear surfaces of the ceramic support 10 may be printed so as not to overlap each other except for end portions having via holes. By designing the wiring as described above, it is possible to generate heat evenly and uniformly over the entire area of the ceramic support.

The resist hole facilitates the connection of the metal resistor pattern through the via hole in the laminate when the ceramic support layer on which the metal resistor pattern is printed and the ceramic protective layer protecting the pattern is easily stacked. Make it consistent. Therefore, mass production of a laminated plate ceramic heater is possible in one printing process and a lamination process.

FIG. 2 schematically shows the lamination of the metal protective layer protective ceramic layers 11a and 11b on both surfaces of the ceramic support 10 on which the metal resistor patterns 16a and 16b are printed on both surfaces. The ceramic protective layers 11a and 11b protecting the metal resistor patterns 16a and 16b are simultaneously stacked on the front and rear surfaces of the ceramic support 10 on which the metal resistor patterns are printed. In this process, the resident holes 12 formed near the edges of the ceramic support 10 and the ceramic protective layers 11a and 11b may be easily aligned by allowing the relative positions of the respective sheets to be fixed at the time of lamination. The ledge holes 12 may be formed in the ceramic support 10 and the ceramic protective layers 11a and 11b through punching, respectively. The ledge hole is used to align a fixing means such as a fine screw of a laminated plate to which a pressure or a temperature is applied when laminating a ceramic support or a protective layer in the interior 12 '.

In FIG. 2, for convenience, only one metal resistor pattern is formed on the front and rear surfaces of the ceramic support 10, but in practice, it is more preferable to form a plurality of patterns.

FIG. 3A shows a cross section of a plate-shaped ceramic heater stacked in the manner shown in FIG. 2. As shown, the metal resistor patterns 16a and 16b printed on the ceramic support 10 are designed so that they do not face each other vertically at the top and the bottom of the ceramic support so that the heat generated in the ceramic heater is uniform with respect to the total area of the heater. To occur. That is, it is preferable that the pattern does not overlap in plan view and the metal resistor pattern is formed over most of the area of the ceramic support. The upper metal resistor pattern 16a is electrically connected to the lower metal resistor pattern 16b by the conductive material 14 'filled in the via hole.

FIG. 3B illustrates in more detail the metal resistor patterns 16a and 16b printed on both surfaces of the ceramic support 10 by the conductive material 14 ′ filling the via holes. One or more via holes are formed by punching one or more of them to suit the size of the metal resistor pattern, and the size of the via holes is preferably not exceeding the width of the pattern.

Preferably, the via hole is formed at an end of the metal resistor pattern, and the end of the metal resistor pattern of one layer is formed to be perpendicular to the end of the metal resistor pattern of the other layer, and thus each metal resistor pattern is formed through the via hole. Make sure that a part of the (usually the end) is connected.

Next, a ceramic heater according to a second embodiment of the present invention will be described. 4 shows a plurality of ceramic supports 20a, 20b, and 20c in which the metal resistor patterns 26a, 26b, and 26c are printed on only one surface, and the via holes 24 and the resist holes 22 connecting the metal resistor patterns are formed. ) And a plate-shaped ceramic heater having a laminated structure using one ceramic protective layer 21 are shown. As in the first embodiment, the via holes 24 are punched in the ceramic supports 20a, 20b, and 20c so that the metal resistor patterns 26a, 26b, and 26c of each layer are interconnected. The ceramic supports 20a, 20b, and 20c having the metal resistor patterns 26a, 26b, and 26c formed on only one surface thereof are stacked in one direction with the metal resistor pattern formed thereon, and then one ceramic protective layer 21 is formed on the top layer. By laminating, a ceramic heater can be completed. Such a laminated structure can increase the amount of the metal resistor pattern without increasing the area of the ceramic support, and can form various multilayer structures of at least two or more layers, thereby providing a ceramic heater having excellent heat generation characteristics.

5A, 5B, and 5C show the ceramic supports of the second, third, and fourth layers constituting the laminate of the plate-shaped ceramic heaters according to the second embodiment, and the metal resistor patterns formed on the upper surfaces thereof, respectively. .

In the ceramic heater according to the second embodiment, the metal resistor pattern 26a on the ceramic support 20a of the first layer may be connected to the metal resistor pattern 26b on the ceramic support 20b of the second layer. It may also be directly connected to the metal resistor pattern 26c on the ceramic support 20c of the third layer. 6 illustrates this connection state in detail. Each of the metal resistor patterns 26a, 26b, and 26c may be electrically connected by a conductive material 24 ′ filled in the via hole. The plurality of metal resistor patterns 26a, 26b, and 26c formed on one surface of the ceramic support 20a, 20b, and 20c may be printed so as not to overlap each other except for end portions having via holes. By designing the wiring as described above, it is possible to generate heat evenly and uniformly with respect to the entire area of the ceramic support.

In the ceramic heater according to the present invention, since heat dissipation occurs on both surfaces of the ceramic sheet, the amount of heat generated can be larger than that of the conventional single-sided ceramic heater, and the heat can be generated uniformly. In addition, since a plurality of metal resistor patterns are formed in a small area by arranging and stacking the metal resistor patterns in three dimensions, it is possible to greatly reduce the size of the ceramic heater. In addition, one wide ceramic green sheet is prepared, a metal resistor pattern is formed on (or both surfaces) at the same time, other punching processes are performed simultaneously, the green sheets for the protective layer are laminated, and then a cutting and firing process is performed. Therefore, it is possible to simultaneously manufacture a plurality of ceramic heaters in one process, thereby further improving productivity and yield.

As described above, the ceramic heater according to the present invention uses a ceramic sheet as a support for forming the metal heating element pattern, so that the process of forming the metal heating element pattern is simple, and both sides of the green sheet may be formed by processing via holes. It is possible to connect the metal heating element pattern with a laminate on one side, so that the heating value is larger than the existing heating element, and a uniform ceramic heater can be manufactured. Using a green sheet also protects the ceramic layer to be able to manufacture a ceramic heater with improved mechanical properties such as high impact.

In addition, when the resist holes are processed and laminated on the ceramic green sheet support, it is possible to simultaneously print and stack many resistor patterns on one sheet of green sheet, and the stacking of the metal resistor patterns in each layer of the laminate becomes constant. The defects in the process can be reduced. Thereafter, the laminated ceramic heaters are cut into respective heaters according to a metal resistor pattern before sintering, and then sintered, thereby making it possible to mass-produce a plate-shaped ceramic heater than conventional methods. Therefore, by using the method proposed in the present invention, it is possible to mass-produce highly reliable laminated plate ceramic heater products.

Claims (4)

A ceramic sheet having a plurality of metal patterns formed on upper and lower surfaces, the metal patterns on the upper and lower surfaces being interconnected by via holes, and including at least one resist hole formed at an edge thereof; And A ceramic protective layer stacked on the upper and lower surfaces of the ceramic sheet, the ceramic protective layer including at least one resist hole. Plate-shaped ceramic heater. The plate-shaped ceramic heater of claim 1, wherein the metal patterns formed on the top and bottom surfaces of the ceramic sheet do not vertically cross except portions interconnected by via holes. The plurality of ceramic sheets have a plurality of metal patterns formed on one surface thereof, and each of the ceramic sheets has a via hole for interconnecting the metal patterns, and each of the plurality of ceramic sheets has at least one resist hole formed at an edge thereof. A ceramic laminate in which ceramic sheets are aligned and stacked; And A ceramic protective layer stacked on one surface of the ceramic laminate and including at least one resist hole. Plate-shaped ceramic heater. The plate-shaped ceramic heater of claim 3, wherein the metal patterns formed on one surface of each ceramic sheet do not vertically cross except portions interconnected by via holes.

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