Ceramic heater

Abstract

The present invention relates to a two-zone heating element embedded in a ceramic heater, comprising first and second heating sections which can be independently controlled by a power supply; a first non-heating section which is disposed between first and second sub-heating sections constituting the first heating section and electrically connects the first and second sub-heating sections; and a second non-heating section which is disposed between the second heating section and a first electrode terminal and electrically connects the second heating section and the first electrode terminal.

Description

[Technical field]

[0001] The present invention relates to ceramic heaters, and more particularly to ceramic heaters with improved reliability. [Background technology]

[0002] Ceramic heaters are used to heat-treat various objects to be heat-treated, such as semiconductor wafers, glass substrates, and flexible substrates, at a predetermined heating temperature. In general, a ceramic heater includes a heater body part made of a ceramic plate and a heater support part attached to the lower part of the heater body part, and the heater body part includes a heating element having a predetermined resistance. The temperature distribution of the heating surface of the ceramic heater can be adjusted by the arrangement and design of the heating element embedded in the ceramic plate, and the temperature distribution of the heating surface of the ceramic heater may be adjusted by changing the spacing between the heating elements, the shape of the heating elements, the material of the heating elements, and the thickness of the heating elements.

[0003] The temperature distribution formed on the heating surface of a ceramic heater may vary depending on the properties of the object to be heat-treated. In this case, when a ceramic heater is designed using only one heating element, various temperature distributions can be realized by varying the embedding interval, embedding shape, material, and thickness of the heating element embedded in the ceramic heater. However, since the ceramic plate of a ceramic heater has high thermal conductivity, it is difficult to uniformly realize various temperature distributions required by the properties of the object to be heat-treated in each region using heating elements controlled with the same power. For this reason, ceramic heaters in which two or more heating elements that can be independently controlled are embedded have been proposed in recent years.

[0004] 1 is a diagram illustrating the structure of a two-zone heating element embedded in a conventional ceramic heater. As shown in FIG. 1, the conventional two-zone heating element 10 includes a first heating section 11, a second heating section 12, and a non-heating section 13.

[0005] A first electrode terminal 20 and a second electrode terminal 30 are embedded in the ceramic plate corresponding to the center portion of the heating element 10. The first electrode terminal 20 contacts the lower surface of the heating element 10 and serves to electrically connect the first heating portion 11 of the heating element 10 to a first heating element rod (not shown). The second electrode terminal 30 contacts the lower surface of the heating element 10 and serves to electrically connect the non-heating portion 13 of the heating element 10 to a second heating element rod (not shown).

[0006] The first heating part 11 is formed at a position corresponding to the inner zone of the ceramic heater heating surface, and the second heating part 12 is formed at a position corresponding to the outer zone of the ceramic heater heating surface. The first and second heating parts 11 and 12 are disposed at a certain distance from each other. In addition, the first and second heating parts 11 and 12 are electrically separated from each other and driven independently of each other.

[0007] The non-heating part 13 is disposed between the second electrode terminal 30 and the second heating part 12, and serves to electrically connect the second electrode terminal 30 and the second heating part 12. The non-heating part 13 is formed extending from the center of the heating surface of the ceramic heater toward the periphery. The non-heating part 13 is generally formed in a straight line having a length of 100 mm to 120 mm.

[0008] However, in the conventional two-zone heating element 10, a problem occurs in the sintering / heat treatment process where cracks occur at various positions within the area where the ceramic plate and the non-heating portion 13 come into contact due to the difference in thermal expansion coefficient between the aluminum nitride material constituting the ceramic plate and the metal material constituting the non-heating portion 13. To solve this problem, a method for shortening the length of the non-heating portion 13 is required. Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention seeks to overcome the above-mentioned problems and other problems, and it is yet another object of the present invention to provide a ceramic heater having improved reliability.

[0010] A further object is to provide a ceramic heater having improved temperature uniformity.

[0011] Yet another object is to provide a ceramic heater having an embedded multi-zone heating element including two or more heating parts that can be independently controlled and two or more non-heating parts connected to the heating parts.

[0012] Still another object is to provide a ceramic heater having an embedded multi-zone heating element including two or more non-heat-generating portions whose linear length is shorter than that of a conventional ceramic heater. [Means for solving the problem]

[0013] In order to achieve the above or other objects, according to one aspect of the present invention, there is provided a ceramic heater having an embedded two-zone heating element, the ceramic heater including first and second heating sections that can be independently controlled by a power supply device; a first non-heating section that is disposed between first and second sub-heating sections that constitute the first heating section and electrically connects the first and second sub-heating sections; and a second non-heating section that is disposed between the second heating section and a first electrode terminal and electrically connects the second heating section and the first electrode terminal.

[0014] According to another aspect of the present invention, there is provided a ceramic heater in which a 4-zone heating element is embedded, the ceramic heater including: first to fourth heating sections that can be independently controlled by a power supply; first and second non-heating sections that are disposed opposite each other with respect to a first axis of symmetry between the first heating section and the second heating section and that are disposed a certain distance away from a center of the 4-zone heating element; and third and fourth non-heating sections that are disposed opposite each other with respect to a second axis of symmetry between the third heating section and the fourth heating section and that extend from first and second electrode terminals disposed at the center of the 4-zone heating element toward the third and fourth heating sections.

[0015] According to yet another aspect of the present invention, there is provided a ceramic heater in which a 6-zone heating element is embedded, the ceramic heater including: first to sixth heating sections which can be independently controlled by a power supply; first to third non-heating sections which are disposed at a certain distance from the center of the 6-zone heating element and which are arranged at an angle of 120° with respect to the center of the 6-zone heating element; and fourth to sixth non-heating sections which extend from first to third electrode terminals which are disposed at the center of the 6-zone heating element in the direction of the fourth to sixth heating sections and which are arranged at an angle of 120° with respect to the center of the 6-zone heating element. Effect of the Invention

[0016] According to at least one of the embodiments of the present invention, a two-zone heating element including two non-heating portions with a shorter linear length than the conventional one is provided, which has the advantage of reducing thermal stress caused by the non-heating portions, thereby effectively reducing the occurrence of cracks in the area where the non-heating portions contact the ceramic plate.

[0017] In addition, according to at least one of the embodiments of the present invention, a 4-zone heating element including four non-heating portions whose linear length is shorter than that of the conventional art is provided, thereby reducing thermal stress caused by the non-heating portions, and thus effectively reducing the occurrence of cracks in the area where the non-heating portions contact the ceramic plate.

[0018] In addition, according to at least one of the embodiments of the present invention, a 6-zone heating element including 6 non-heating portions whose linear length is shorter than that of the conventional art is provided, thereby reducing thermal stress caused by the non-heating portions, and thus effectively reducing the occurrence of cracks in the area where the non-heating portions contact the ceramic plate.

[0019] However, the effects that can be achieved by the ceramic heater according to the embodiment of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those having ordinary skill in the technical field to which the present invention pertains from the following description. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 illustrates the structure of a two-zone heating element embedded in a conventional ceramic heater. [Diagram 2] 1 is a perspective view showing the outer shape of a ceramic heater according to an embodiment of the present invention. [Diagram 3] FIG. 1 is a cross-sectional view showing a configuration of a ceramic heater according to an embodiment of the present invention. [Figure 4] FIG. 2 is a diagram showing the structure of a two-zone heating element according to one embodiment of the present invention. [Diagram 5] FIG. 5 is a diagram showing the detailed structure of the elements that make up the two-zone heating element of FIG. 4. [Figure 6] FIG. 5 is an enlarged view of part A in FIG. 4. [Figure 7] FIG. 2 is a diagram showing the structure of a four-zone heating element according to one embodiment of the present invention. [Figure 8] FIG. 8 is a diagram showing the detailed structure of the elements that make up the 4-zone heating element of FIG. 7. [Figure 9] FIG. 2 is a diagram showing the structure of a 6-zone heating element according to one embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing the detailed structure of the elements that make up the 6-zone heating element of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, the embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings. The same reference numbers are used for the same or similar components regardless of the drawing numbers, and the repeated description thereof will be omitted. In the following description of the embodiments of the present invention, when it is described that each layer (film), region, pattern, or structure is formed "on" or "under" a substrate, each layer (film), region, pad, or pattern, it may include any case where it is formed "directly" or "indirectly through another layer" "on" or "under". In addition, the reference to "on" or "under" each layer will be described with reference to the drawings. In the drawings, the thickness and size of each layer are exaggerated, omitted, or shown roughly for convenience and clarity of explanation. In addition, the size of each component does not fully reflect the actual size.

[0022] In addition, when describing the embodiments disclosed in this specification, if it is determined that a specific description of related publicly known technology may obscure the gist of the embodiments disclosed in this specification, the detailed description will be omitted. In addition, the attached drawings are merely for facilitating understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings, and should be understood to include any modifications, equivalents, or alternatives included in the idea and technical scope of the present invention.

[0023] The present invention proposes a ceramic heater with improved reliability.The present invention also proposes a ceramic heater with improved temperature uniformity.The present invention also proposes a ceramic heater having an embedded multi-zone heating element including two or more heating parts that can be independently controlled and two or more non-heating parts connected to the two or more heating parts.The present invention also proposes a ceramic heater having an embedded multi-zone heating element including two or more non-heating parts whose linear length is shorter than that of conventional ceramic heaters.

[0024] Various embodiments of the invention will now be described in detail with reference to the drawings.

[0025] FIG. 2 is a perspective view showing the outer shape of a ceramic heater according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view showing the configuration of the ceramic heater according to an embodiment of the present invention.

[0026] Referring to Figs. 2 and 3, a ceramic heater 100 according to an embodiment of the present invention is a semiconductor device that supports various objects to be heat-treated, such as a semiconductor wafer, a glass substrate, a flexible substrate, etc., and heats the object to be heat-treated to a predetermined temperature.

[0027] The ceramic heater 100 may include a heater body part 110 that stably holds an object to be heat-treated (not shown) and transfers heat, and a heater support part 120 that is attached to a lower part of the heater body part 110. Meanwhile, although not shown, an adhesive layer (not shown) may be formed between the heater body part 110 and the heater support part 120.

[0028] The heater body part 110 may be formed as a plate-like structure having a predetermined shape, for example, but is not limited to, a circular plate-like structure.

[0029] A pocket region (or cavity region, 111) having a recessed structure with a predetermined step may be formed on the upper part of the heater body part 110 so that an object to be heat-treated such as a wafer can be stably mounted. The upper surface of the heater body part 110 corresponding to the pocket region may be formed to have excellent flatness so that an object to be heat-treated placed in the chamber can be arranged horizontally without being tilted to one side.

[0030] The heater body 110 may be made of a plurality of ceramic plates (not shown) made of a ceramic material having excellent thermal conductivity, and may be formed by performing a compression sintering process on the plurality of ceramic plates. Here, the ceramic material may be Al. 2 O 3 , Y 2O 3 , Al 2 O 3 / Y 2 O 3 , ZrO 2 , AlC (Autoclaved lightweight concrete), TiN, AlN, TiC, MgO, CaO, CeO 2 , TiO 2 , B x C y , BN, SiO 2 , SiC, YAG, Mullite, AlF 3 The material may be at least one of these, and more preferably, may be aluminum nitride (AlN).

[0031] The heater body part 110 may include a heating element 112 and a plurality of electrode terminals 113, 114 in contact with a lower surface of the heating element 112. Meanwhile, although not shown, the heater body part 110 may include a radio frequency electrode for performing an RF (Radio Frequency) grounding function and / or an electrostatic chuck function.

[0032] The heating element 112 may function to heat an object to be heat-treated located on an upper surface of the heater body part 110 to a constant temperature in order to perform deposition and etching processes smoothly in a semiconductor manufacturing process.

[0033] The heating element 112 may be embedded in the heater body portion 110 at a position corresponding to the position of the heat treatment object. The heating element 112 may be embedded in the heater body portion 110 parallel to the heat treatment object so that the heating temperature can be uniformly controlled depending on the position to heat the heat treatment object uniformly as a whole, and the distance over which heat is transferred to the heat treatment object is kept constant at almost all positions.

[0034] The heating element 112 may be formed in a shape corresponding to the shape of the object to be heat-treated, and may be formed in the form of a plate-like coil using a heating wire (or a resistance wire) or a flat plate.

[0035] The heating element 112 is made of tungsten (W), molybdenum (Mo), molybdenum carbide (Mo 2 C, MoC, Mo 3 C 2 ), silver (Ag), gold (Au), platinum (Pt), niobium (Nb), titanium (Ti), or alloys thereof.

[0036] In particular, the heating element 112 according to this embodiment may be a multi-zone heating element including two or more heating parts that can be controlled independently and two or more non-heating parts connected to the two or more heating parts. The heating element 112 includes two or more non-heating parts whose linear length is shorter than that of the conventional heating element, and thus can effectively reduce thermal stress caused by the non-heating parts.

[0037] The electrode terminals 113 and 114 may contact the lower surface of the heating element 112 and function to electrically connect the heating portion of the heating element 112 to the heating element rods 121 and 122 .

[0038] A plurality of electrode terminals 113, 114 may be embedded in a ceramic plate corresponding to the central portion of the heating element 112, that is, the portion where the heater body portion 110 and the heater support portion 120 contact each other.

[0039] The electrode terminals 113 and 114 may be made of a metal material having excellent electrical conductivity. For example, the electrode terminals 113 and 114 may be made of tungsten (W), molybdenum (Mo), silver (Ag), gold (Au), niobium (Nb), titanium (Ti), aluminum nitride (AlN), or an alloy thereof, and more preferably, may be made of molybdenum (Mo).

[0040] The heater support part 120 is attached to the lower part of the heater body part 110 and may play a role of supporting the heater body part 110. The heater support part 120 may be combined with the heater body part 110 to form a ceramic heater 100 having an overall T-shape.

[0041] The heater support 120 may be formed in the form of a cylindrical tube having an empty space therein in order to install a plurality of heating element rods 121 and 122 connected to the heating element 112 of the heater body 110 through the heater support 120.

[0042] The heater support part 120 may be made of the same ceramic material as the heater body part 110. For example, the heater support part 120 may be made of Al 2 O 3 , Y 2 O 3 , Al 2 O 3 / Y 2 O 3 , ZrO 2 , AlC (Autoclaved lightweight concrete), TiN, AlN, TiC, MgO, CaO, CeO 2 , TiO 2 , B x C y , BN, SiO 2 , SiC, YAG, Mullite, AlF 3 The insulating layer 11 may be made of at least one of the above materials, and more preferably, may be made of aluminum nitride (AlN).

[0043] The plurality of heating element rods 121, 122 may be installed inside the heater support part 120 and may have a function of electrically connecting the plurality of electrode terminals 113, 114 to an external power supply (not shown). Thus, the heating part of the heating element 112 embedded in the heater body part 110 may be electrically connected to an external power supply through the plurality of electrode terminals 113, 114 and the heating element rods 121, 122, and may be independently controlled by the external power supply.

[0044] The heating element rods 121 and 122 may be made of a metal material having excellent electrical conductivity. For example, the heating element rods 121 and 122 may be made of copper (Cu), aluminum (Al), iron (Fe), tungsten (W), nickel (Ni), silver (Ag), gold (Au), niobium (Nb), titanium (Ti), or an alloy thereof, and more preferably, nickel (Ni).

[0045] Meanwhile, in the figure, two electrode terminals 113, 114 and two heating rods 121, 122 are illustrated as being installed in the ceramic heater 100, but this is not necessarily limited thereto. The number of electrode terminals and heating rods installed in the ceramic heater corresponds to the number of heating parts that can be independently controlled by an external power supply.

[0046] As described above, the ceramic heater according to one embodiment of the present invention is provided with a multi-zone heating element including two or more non-heating parts whose linear length is shorter than that of conventional ceramic heaters, thereby reducing thermal stress caused by the non-heating parts, and thus effectively reducing the occurrence of cracks in the area where the non-heating parts contact the ceramic plate.

[0047] FIG. 4 is a diagram showing the structure of a two-zone heating element according to one embodiment of the present invention, FIG. 5 is a diagram showing the detailed structure of the elements that make up the two-zone heating element of FIG. 4, and FIG. 6 is an enlarged view of part A of FIG. 4.

[0048] 4 to 6, a two-zone heating element 200 according to an embodiment of the present invention may include first and second heating portions 210 and 220 and first and second non-heating portions 230 and 240.

[0049] The first heating portion (center / edge heating portion) 210 may include a first sub-heating portion (center heating portion) 211 and a second sub-heating portion (edge ​​heating portion) 213. Here, the first and second sub-heating portions 211 and 213 may be electrically connected to each other through a first non-heating portion 230.

[0050] The first sub-heating part 211 may be formed at a position corresponding to a center zone of a heating surface of the ceramic heater, and may be formed in a circular shape.

[0051] The first sub-heating part 211 may include a plurality of concentric circumferences 211a and a plurality of connecting parts 211b connecting the plurality of concentric circumferences 211a. A first end portion located on the inside of the first sub-heating part 211 may be connected to the second electrode terminal 114, and a second end portion located on the outside of the first sub-heating part 211 may be connected to the first non-heating part 230.

[0052] The second sub-heating part 213 may be formed at a position corresponding to an edge zone of the heating surface of the ceramic heater, and may be formed in a ring shape.

[0053] The second sub-heating portion 213 may include a plurality of concentric circumferences 213a and a plurality of connecting portions 213b connecting the plurality of concentric circumferences 213a. An end portion on the inside of the second sub-heating portion 213 may be connected to the first non-heating portion 230.

[0054] The second heating part (middle heating part) 220 may be formed at a position corresponding to a middle zone of the heating surface of the ceramic heater. That is, the second heating part 220 may be formed to be disposed in a space between the first sub-heating part 211 and the second sub-heating part 213. The second heating part 220 may be formed in a ring shape.

[0055] The second heat generating portion 220 may include a plurality of concentric circumferences 220a and a plurality of connecting portions 220b connecting the plurality of concentric circumferences 220a. An end portion located on the inside of the second heat generating portion 220 may be connected to the second non-heat generating portion 240.

[0056] The first and second heating parts 210 and 220 may be disposed on the same plane of the ceramic plate, or, in another embodiment, the first and second heating parts 210 and 220 may be disposed on different planes.

[0057] The first non-heating part 230 may be disposed between the first sub-heating part 211 and the second sub-heating part 213 and may have a function of electrically connecting the first and second sub-heating parts 211 and 213. The first non-heating part 230 may be formed to extend in a straight line from a point on the first sub-heating part 211 to a point on the second sub-heating part 213.

[0058] Meanwhile, although not shown, in another embodiment, the first non-heating portion 230 may be formed to extend in a curved shape from a point on the first sub-heating portion 211 to a point on the second sub-heating portion 213. In still another embodiment, the first non-heating portion 230 may be formed to extend in a shape that combines a straight line and a curved line from a point on the first sub-heating portion 211 to a point on the second sub-heating portion 213.

[0059] A first end of the first non-heating part 230 may be connected to a second end located on the outside of the first sub-heating part 211, and a second end of the first non-heating part 230 may be connected to an end located on the inside of the second sub-heating part 213. In this case, the first non-heating part 230 may be connected to the second sub-heating part 213 through a first connecting member 250 as shown in FIG. 6(a). The first connecting member 250 may be configured to include an opening into which wires of different diameters constituting the first non-heating part 230 and the second sub-heating part 213 are press-fitted and fixed. Meanwhile, as another embodiment, the first non-heating part 230 may be directly connected to the second sub-heating part 213 without a separate connecting member as shown in FIG. 6(b).

[0060] The first non-heating portion 230 may include two metal wires arranged parallel to each other. The first non-heating portion 230 may be formed such that an axis of symmetry between the two metal wires crosses the center of the heating element 200.

[0061] The first non-heating portion 230 may be formed to have a linear length shorter than that of a non-heating portion included in a conventional two-zone heating element. For example, if the linear length of a conventional non-heating portion is 100 mm to 120 mm, the first non-heating portion 230 may be formed to have a linear length (60 mm to 70 mm) that is approximately 60% of the conventional length.

[0062] The first non-heating portion 230 may be formed to have a first length that is shorter than or equal to the straight line length between a point of the second sub-heating portion 213 and the second electrode terminal 114 .

[0063] The second non-heating part 240 may be disposed between the first electrode terminal 113 and the second heat-generating part 220, and may have a function of electrically connecting the first electrode terminal 113 and the second heat-generating part 220. The second non-heating part 240 may be formed to extend in a straight line from the first electrode terminal 113 to a point on the second heat-generating part 220.

[0064] Meanwhile, although not shown, in another embodiment, the second non-heating portion 240 may be formed to extend in a curved shape from the first electrode terminal 113 to a point on the second heat-generating portion 220. In yet another embodiment, the second non-heating portion 240 may be formed to extend in a shape that combines a straight line and a curved line from the first electrode terminal 113 to a point on the second heat-generating portion 220.

[0065] A first end of the second non-heating part 240 may be connected to the first electrode terminal 113, and a second end of the second non-heating part 240 may be connected to an end located inside the second heat-generating part 220. In this case, the second non-heating part 240 may be connected to the second heat-generating part 220 through a second connecting member 260 as shown in FIG. 6(a). Similarly, the second connecting member 260 may be configured to include an opening into which wires of different diameters constituting the second non-heating part 240 and the second heat-generating part 220 are press-fitted and fixed. Meanwhile, as another embodiment, the second non-heating part 240 may be directly connected to the second heat-generating part 220 without a separate connecting member as shown in FIG. 6(b).

[0066] The second non-heating part 240 may include two metal wires arranged parallel to each other. The second non-heating part 240 may be formed such that an axis of symmetry between the two metal wires crosses the center of the heating element 200.

[0067] The second non-heating portion 240 may be disposed in a direction facing the first non-heating portion 230 with respect to the center of the heating element 200. The first and second non-heating portions 230, 240 may be disposed on a straight line crossing the center of the heating element 200, and more preferably, on a horizontal line crossing the center of the heating element 200.

[0068] The second non-heating portion 240 may be formed to have a linear length that is the same as or different from the linear length of the first non-heating portion 230. The second non-heating portion 240 may be formed to have a linear length that is shorter than the linear length of a non-heating portion included in a conventional two-zone heating element. As an example, if the linear length of a conventional non-heating portion is 100 mm to 120 mm, the second non-heating portion 240 may be formed to have a linear length (60 mm to 70 mm) that is about 60% of the conventional length.

[0069] The second non-heating portion 240 may be formed to have a second length that is shorter than or equal to the straight line length between a point of the second sub-heating portion 213 and the first electrode terminal 113 .

[0070] The first and second heat generating portions 210, 220, the first and second non-heat generating portions 230, 240, and the first and second connecting members 250, 260 may all be made of the same material, but are not necessarily limited to this.

[0071] As described above, the two-zone heating element according to an embodiment of the present invention has two non-heating parts with shorter linear lengths than conventional ones, thereby reducing thermal stress caused by the non-heating parts, and thus effectively reducing cracks in the area where the non-heating parts contact the ceramic plate. In addition, the two-zone heating element can improve the temperature uniformity of the ceramic heater heating surface by independently controlling two areas of the ceramic heater heating surface to realize various temperature distributions.

[0072] FIG. 7 is a diagram showing the structure of a 4-zone heating element according to one embodiment of the present invention, and FIG. 8 is a diagram showing the detailed structure of the elements that make up the 4-zone heating element of FIG.

[0073] 7 and 8, a 4-zone heating element 300 according to an embodiment of the present invention may include first to fourth heating portions 310-340 and first to fourth non-heating portions 350-380.

[0074] The first heating part 310 may include a first sub-heating part 311 and a second sub-heating part 313. Here, the first and second sub-heating parts 311 and 313 may be electrically connected to each other through a first non-heating part 350.

[0075] The second heating part 320 may include a third sub-heating part 321 and a fourth sub-heating part 323. Here, the third and fourth sub-heating parts 321 and 323 may be electrically connected to each other through a second non-heating part 360.

[0076] The first and second heating parts 310 and 320 may be formed symmetrically with respect to a horizontal axis that crosses the center of the heating element 300. In addition, the first and second heating parts 310 and 320 may be disposed opposite to each other with respect to the horizontal axis that crosses the center of the heating element 300.

[0077] The first and third sub-heating parts 311 and 321 may be formed at positions corresponding to a center zone of a heating surface of the ceramic heater. The first and third sub-heating parts 311 and 321 may include a plurality of concentric circumferences 311a and 321a and a plurality of connecting parts 311b and 321b connecting the plurality of concentric circumferences 311a and 321a.

[0078] The first and third sub-heating parts 311 and 321 may be formed to have the same shape, for example, the first and third sub-heating parts 311 and 321 may be formed to have a semicircular shape.

[0079] A first end of the first sub-heating part 311 may be connected to the third electrode terminal 115, and a second end of the first sub-heating part 311 may be connected to the first non-heating part 350. A first end of the third sub-heating part 321 may be connected to the fourth electrode terminal 116, and a second end of the third sub-heating part 321 may be connected to the second non-heating part 360.

[0080] The second and fourth sub-heating parts 313 and 323 may be formed at positions corresponding to edge zones of the heating surface of the ceramic heater. The second and fourth sub-heating parts 313 and 323 may include a plurality of concentric circumferences 313a and 323a and a plurality of connecting parts 313b and 323b connecting the plurality of concentric circumferences 313a and 323a.

[0081] The second and fourth sub-heating parts 313 and 323 may be formed to have the same shape as each other, for example, the second and fourth sub-heating parts 313 and 323 may be formed in a semi-annular shape.

[0082] An end of the second sub-heating part 313 may be connected to the first non-heating part 350. An end of the fourth sub-heating part 323 may be connected to the second non-heating part 360.

[0083] The third and fourth heating parts 330 and 340 may be formed at positions corresponding to a middle zone of the heating surface of the ceramic heater. More specifically, the third heating part 330 may be formed to be disposed in a space between the first and third sub-heating parts 311 and 321 and the second and fourth sub-heating parts 313 and 323. The fourth heating part 340 may be formed to be disposed in a space between the first and third sub-heating parts 311 and 321 and the second and fourth sub-heating parts 313 and 323. The fourth heating part 340 may be formed in a semi-annular shape.

[0084] The third and fourth heating parts 330 and 340 may be formed symmetrically with respect to a vertical axis that crosses the center of the heating element 300. In addition, the third and fourth heating parts 330 and 340 may be disposed opposite to each other with respect to the vertical axis that crosses the center of the heating element 300.

[0085] The third and fourth heating parts 330 and 340 may be formed to have the same shape, for example, the third and fourth heating parts 330 and 340 may be formed in a semicircular shape.

[0086] The third and fourth heating portions 330, 340 may include a plurality of concentric circumferences 330a, 340a and a plurality of connecting portions 330b, 340b connecting the plurality of concentric circumferences 330a, 340a.

[0087] The first to fourth heat generating parts 310 to 340 may be disposed on the same plane of the ceramic plate, or, in another embodiment, at least one of the first to fourth heat generating parts 310 to 340 may be disposed on different planes.

[0088] The first non-heating part 350 may be disposed between the first sub-heating part 311 and the second sub-heating part 313 and may have a function of electrically connecting the first and second sub-heating parts 311 and 313. The first non-heating part 350 may be formed to extend in a straight line from a point on the first sub-heating part 311 to a point on the second sub-heating part 313.

[0089] The first non-heating part 350 may be connected to the second sub-heating part 313 through a connecting member (not shown). Meanwhile, in another embodiment, the first non-heating part 350 may be directly connected to the second sub-heating part 313 without a separate connecting member.

[0090] The second non-heating part 360 may be disposed between the third sub-heating part 321 and the fourth sub-heating part 323 and may have a function of electrically connecting the third and fourth sub-heating parts 321 and 323. The second non-heating part 360 may be formed to extend in a straight line from a point on the third sub-heating part 321 to a point on the fourth sub-heating part 323.

[0091] The second non-heating part 360 may be connected to the fourth sub-heating part 323 through a connecting member (not shown). Meanwhile, in another embodiment, the second non-heating part 360 may be directly connected to the fourth sub-heating part 323 without a separate connecting member.

[0092] The first and second non-heating parts 350 and 360 may include two metal wires arranged parallel to each other. The first and second non-heating parts 350 and 360 may be formed such that an axis of symmetry between the two metal wires crosses the center of the heating element 300.

[0093] The first and second non-heating portions 350, 360 may be formed to have a linear length shorter than that of a non-heating portion included in a conventional 4-zone heating element. For example, if the linear length of a conventional non-heating portion is 100 mm to 120 mm, the first and second non-heating portions 350, 360 may be formed to have a linear length (60 mm to 70 mm) that is approximately 60% of the conventional length.

[0094] The first non-heating portion 350 may be formed to have a first length that is shorter than or equal to the straight-line length between a point of the second sub-heating portion 313 and the third electrode terminal 115, and the second non-heating portion 360 may be formed to have a first length that is shorter than or equal to the straight-line length between a point of the fourth sub-heating portion 323 and the fourth electrode terminal 116.

[0095] The first and second non-heating parts 350, 360 may be disposed opposite each other with respect to a horizontal axis that crosses the center of the heating element 300. That is, the first and second non-heating parts 350, 360 may be disposed opposite each other with respect to an axis of symmetry between the first heating part 310 and the second heating part 320. The first and second non-heating parts 350, 360 may be disposed at a certain distance from the center of the heating element 300.

[0096] The first and second non-heating portions 350 , 360 may be arranged on a straight line that crosses the center of the heating element 300 , and more preferably, on a perpendicular line that crosses the center of the heating element 300 .

[0097] The third non-heating portion 370 may be disposed between the first electrode terminal 113 and the third heat-generating portion 330, and may have a function of electrically connecting the first electrode terminal 113 and the third heat-generating portion 330. The third non-heating portion 370 may be formed to extend in a straight line from the first electrode terminal 113 to a point on the third heat-generating portion 330.

[0098] The third non-heating part 370 may be connected to the third heating part 330 through a connecting member (not shown). Meanwhile, in another embodiment, the third non-heating part 370 may be directly connected to the third heating part 330 without a separate connecting member.

[0099] The fourth non-heating part 380 may be disposed between the second electrode terminal 114 and the fourth heat-generating part 340, and may have a function of electrically connecting the second electrode terminal 114 and the fourth heat-generating part 340. The fourth non-heating part 380 may be formed to extend in a straight line from the second electrode terminal 114 to a point on the fourth heat-generating part 340.

[0100] The fourth non-heating part 380 may be connected to the fourth heating part 340 through a connecting member (not shown). Meanwhile, in another embodiment, the fourth non-heating part 380 may be directly connected to the fourth heating part 340 without a separate connecting member.

[0101] The third and fourth non-heating parts 370 and 380 may include two metal wires arranged parallel to each other. The third and fourth non-heating parts 370 and 380 may be formed such that an axis of symmetry between the two metal wires crosses the center of the heating element 300.

[0102] The third and fourth non-heating portions 370, 380 may be formed to have a linear length shorter than that of a non-heating portion included in a conventional 4-zone heating element. For example, if the linear length of a conventional non-heating portion is 100 mm to 120 mm, the third and fourth non-heating portions 370, 380 may be formed to have a linear length (60 mm to 70 mm) that is approximately 60% of the conventional length.

[0103] The third non-heating portion 370 may be formed to have a second length shorter than or equal to a straight line length between a point of any one of the second sub-heating portion 313 and the fourth sub-heating portion 323 and the first electrode terminal 113, and the fourth non-heating portion 380 may be formed to have a second length shorter than or equal to a straight line length between a point of any one of the second sub-heating portion 313 and the fourth sub-heating portion 323 and the second electrode terminal 114. The third and fourth non-heating portions 370 and 380 may be formed to have the same straight line length as the first and second non-heating portions 350 and 360 or may have a different straight line length.

[0104] The third and fourth non-heating sections 370, 380 may be disposed opposite each other with respect to a vertical axis that crosses the center of the heating element 300. That is, the third and fourth non-heating sections 370, 380 may be disposed opposite each other with respect to an axis of symmetry between the third heating section 330 and the fourth heating section 340. The third and fourth non-heating sections 370, 380 may be disposed on a straight line that crosses the center of the heating element 300, and more preferably on a horizontal line that crosses the center of the heating element 300.

[0105] Meanwhile, in this embodiment, the first to fourth non-heating portions 350 to 380 are illustrated as extending in a straight line, but this is not necessarily limited thereto, and it will be apparent to those skilled in the art that the non-heating portions may extend in a curved line instead of in a straight line, or may extend in a form that combines a straight line and a curved line.

[0106] The first to fourth heat generating portions 310 to 340, the first to fourth non-heat generating portions 350 to 380, and the first to fourth connecting members (not shown) may all be made of the same material, but are not necessarily limited to this.

[0107] As described above, the 4-zone heating element according to an embodiment of the present invention has four non-heating parts with shorter linear lengths than the conventional one, thereby reducing thermal stress caused by the non-heating parts, and thus effectively reducing the occurrence of cracks in the area where the non-heating parts contact the ceramic plate. In addition, the 4-zone heating element can improve the temperature uniformity of the ceramic heater heating surface by independently controlling the four regions of the ceramic heater heating surface to realize various temperature distributions.

[0108] FIG. 9 is a diagram showing the structure of a 6-zone heating element according to one embodiment of the present invention, and FIG. 10 is a diagram showing the detailed structure of the elements that make up the 6-zone heating element of FIG.

[0109] 9 and 10, a 6-zone heating element 400 according to an embodiment of the present invention may include first to sixth heating portions 410-460 and first to sixth non-heating portions 510-560.

[0110] The first heating part 410 may include a first sub-heating part 411 and a second sub-heating part 413. Here, the first and second sub-heating parts 411 and 413 may be electrically connected to each other through a first non-heating part 510.

[0111] The second heating part 420 may include a third sub-heating part 421 and a fourth sub-heating part 423. Here, the third and fourth sub-heating parts 421 and 423 may be electrically connected to each other through a second non-heating part 520.

[0112] The third heating part 430 may include a fifth sub-heating part 431 and a sixth sub-heating part 433. Here, the fifth and sixth sub-heating parts 431 and 433 may be electrically connected to each other through the third non-heating part 530.

[0113] The first, third and fifth sub-heating parts 411, 421 and 431 may be formed at positions corresponding to a center zone of a heating surface of the ceramic heater. The first, third and fifth sub-heating parts 411, 421 and 431 may include a plurality of concentric circumferences 411a, 421a and 431a and a plurality of connecting parts 411b, 421b and 431b connecting the plurality of concentric circumferences 411a, 421a and 431a.

[0114] The first, third and fifth sub-heating parts 411, 421 and 431 may be formed to have the same shape. For example, the first, third and fifth sub-heating parts 411, 421 and 431 may be formed in a sector shape.

[0115] A first end of the first sub-heating part 411 may be connected to the fourth electrode terminal 116, and a second end of the first sub-heating part 411 may be connected to the first non-heating part 510. A first end of the third sub-heating part 421 may be connected to the fifth electrode terminal 117, and a second end of the third sub-heating part 520. A first end of the fifth sub-heating part 431 may be connected to the sixth electrode terminal 118, and a second end of the fifth sub-heating part 431 may be connected to the third non-heating part 530.

[0116] The second, fourth and sixth sub-heating parts 413, 423 and 433 may be formed at positions corresponding to edge zones of the heating surface of the ceramic heater. The second, fourth and sixth sub-heating parts 413, 423 and 433 may be formed at positions corresponding to edge zones of the heating surface of the ceramic heater. The plurality of concentric circumferences 413a, 423a, 433a may include a plurality of connecting portions 413b, 423b, 433b that connect the plurality of concentric circumferences 413a, 423a, 433a.

[0117] The second, fourth, and sixth sub-heating parts 413, 423, and 433 may be formed to have the same shape as each other. For example, the second, fourth, and sixth sub-heating parts 413, 423, and 433 may be formed in the shape of three equal rings.

[0118] An end of the second sub-heating part 413 may be connected to the first non-heating part 510. An end of the fourth sub-heating part 423 may be connected to the second non-heating part 520. An end of the sixth sub-heating part 433 may be connected to the third non-heating part 530.

[0119] The fourth to sixth heating parts 440 to 460 may be formed at positions corresponding to the middle zone of the ceramic heater heating surface. More specifically, the fourth heating part 440 may be formed to be disposed in the space between the first and third sub-heating parts 411, 421 and the second and fourth sub-heating parts 413, 423. The fifth heating part 450 may be formed to be disposed in the space between the third and fifth sub-heating parts 421, 431 and the fourth and sixth sub-heating parts 423, 433. The sixth heating part 460 may be formed to be disposed in the space between the first and fifth sub-heating parts 411, 431 and the second and sixth sub-heating parts 413, 433.

[0120] The fourth to sixth heat generating portions 440 to 460 may be formed to have the same shape as one another. For example, the fourth to sixth heat generating portions 440 to 460 may be formed in the shape of a ring divided into three equal parts.

[0121] The fourth to sixth heat generating portions 440 to 460 may include a plurality of concentric circumferences 440a, 450a, 460a, and a plurality of connecting portions 440b, 450b, 460b connecting the plurality of concentric circumferences 440a, 450a, 460a.

[0122] The first to sixth heat generating parts 410 to 460 may be disposed on the same plane of the ceramic plate, while in another embodiment, at least one of the first to sixth heat generating parts 410 to 460 may be disposed on different planes.

[0123] The first non-heating part 510 may be disposed between the first sub-heating part 411 and the second sub-heating part 413 and may have a function of electrically connecting the first and second sub-heating parts 411 and 413. The first non-heating part 510 may be formed to extend in a straight line from a point on the first sub-heating part 411 to a point on the second sub-heating part 413.

[0124] The first non-heating part 510 may be connected to the second sub-heating part 413 through a connecting member (not shown). Meanwhile, in another embodiment, the first non-heating part 510 may be directly connected to the second sub-heating part 413 without a separate connecting member.

[0125] The second non-heating part 520 may be disposed between the third sub-heating part 421 and the fourth sub-heating part 423 and may have a function of electrically connecting the third and fourth sub-heating parts 421 and 423. The second non-heating part 520 may be formed to extend in a straight line from a point on the third sub-heating part 421 to a point on the fourth sub-heating part 423.

[0126] The second non-heating part 520 may be connected to the fourth sub-heating part 423 through a connecting member (not shown). Meanwhile, in another embodiment, the second non-heating part 520 may be directly connected to the fourth sub-heating part 423 without a separate connecting member.

[0127] The third non-heating part 530 may be disposed between the fifth sub-heating part 431 and the sixth sub-heating part 433, and may have a function of electrically connecting the fifth and sixth sub-heating parts 431 and 433. The third non-heating part 530 may be formed to extend in a straight line from a point on the fifth sub-heating part 431 to a point on the sixth sub-heating part 433.

[0128] The third non-heating part 530 may be connected to the sixth sub-heating part 433 through a connecting member (not shown). Meanwhile, in another embodiment, the third non-heating part 530 may be directly connected to the sixth sub-heating part 433 without a separate connecting member.

[0129] The first to third non-heat generating portions 510 to 530 may each include two metal wires arranged parallel to each other. The first to third non-heat generating portions 510 to 530 may be formed such that an axis of symmetry between the two metal wires crosses the center of the heating element 400.

[0130] The first to third non-heating portions 510 to 530 may be formed to have a linear length shorter than that of a non-heating portion included in a conventional 6-zone heating element. For example, if the linear length of a conventional non-heating portion is 100 mm to 120 mm, the first to third non-heating portions 510 to 530 may be formed to have a linear length (60 mm to 70 mm) that is approximately 60% of the conventional length.

[0131] The first non-heating portion 510 may be formed to have a first length that is shorter than or equal to the straight-line length between a point of the second sub-heating portion 413 and the fourth electrode terminal 116, the second non-heating portion 520 may be formed to have a first length that is shorter than or equal to the straight-line length between a point of the fourth sub-heating portion 423 and the fifth electrode terminal 117, and the third non-heating portion 530 may be formed to have a first length that is shorter than or equal to the straight-line length between a point of the sixth sub-heating portion 433 and the sixth electrode terminal 118.

[0132] The first to third non-heating portions 510-530 may be formed to form an angle of 120° with respect to each other with respect to the center of the heating element 400. Furthermore, the first to third non-heating portions 510-530 may be disposed at a fixed distance from the center of the heating element 400. Furthermore, the first to third non-heating portions 510-530 may be formed to have the same linear length.

[0133] The fourth non-heating part 540 may be disposed between the first electrode terminal 113 and the fourth heat-generating part 440, and may have a function of electrically connecting the first electrode terminal 113 and the fourth heat-generating part 440. The fourth non-heating part 540 may be formed to extend in a straight line from the first electrode terminal 113 to a point on the fourth heat-generating part 440.

[0134] The fourth non-heating part 540 may be connected to the fourth heating part 440 through a connecting member (not shown). Meanwhile, in another embodiment, the fourth non-heating part 540 may be directly connected to the fourth heating part 440 without a separate connecting member.

[0135] The fifth non-heating part 550 may be disposed between the second electrode terminal 114 and the fifth heating part 450, and may have a function of electrically connecting the second electrode terminal 114 and the fifth heating part 450. The fifth non-heating part 550 may be formed to extend in a straight line from the second electrode terminal 114 to a point on the fifth heating part 450.

[0136] The fifth non-heating part 550 may be connected to the fifth heating part 450 through a connecting member (not shown). Meanwhile, in another embodiment, the fifth non-heating part 550 may be directly connected to the fifth heating part 450 without a separate connecting member.

[0137] The sixth non-heating part 560 may be disposed between the third electrode terminal 115 and the sixth heat generating part 460, and may have a function of electrically connecting the third electrode terminal 115 and the sixth heat generating part 460. The sixth non-heating part 560 may be formed to extend in a straight line from the third electrode terminal 115 to a point on the sixth heat generating part 460.

[0138] The sixth non-heating part 560 may be connected to the sixth heating part 460 through a connecting member (not shown). Meanwhile, in another embodiment, the sixth non-heating part 560 may be directly connected to the sixth heating part 460 without a separate connecting member.

[0139] The fourth to sixth non-heating portions 540 to 560 may each include two metal wires arranged parallel to each other. The fourth to sixth non-heating portions 540 to 560 may be formed such that an axis of symmetry between the two metal wires crosses the center of the heating element 400.

[0140] The fourth to sixth non-heating portions 540 to 560 may be formed to have a linear length shorter than that of the non-heating portions included in the conventional 6-zone heating element. For example, if the linear length of the conventional non-heating portion is 100 mm to 120 mm, the fourth to sixth non-heating portions 540 to 560 may be formed to have a linear length (60 mm to 70 mm) that is about 60% of the conventional length.

[0141] The fourth non-heating portion 540 may be formed to have a second length shorter than or equal to the straight line length between any one point of the second, fourth, and sixth sub-heating portions 413, 423, and 433 and the first electrode terminal 113, the fifth non-heating portion 550 may be formed to have a second length shorter than or equal to the straight line length between any one point of the second, fourth, and sixth sub-heating portions 413, 423, and 433 and the second electrode terminal 114, and the sixth non-heating portion 560 may be formed to have a second length shorter than or equal to the straight line length between any one point of the second, fourth, and sixth sub-heating portions 413, 423, and 433 and the third electrode terminal 115. The fourth to sixth non-heating portions 540 to 560 may be formed to have the same straight line length as the first to third non-heating portions 510 to 530 or have different straight line lengths.

[0142] The fourth to sixth non-heat generating portions 540 to 560 may be formed to form an angle of 120° with respect to each other with respect to the center of the heat generating element 400. Furthermore, the fourth to sixth non-heat generating portions 540 to 560 may be formed to have the same linear length.

[0143] Meanwhile, in this embodiment, the first to sixth non-heating portions 510 to 560 are illustrated as extending in a straight line, but this is not necessarily limited thereto, and it will be apparent to those skilled in the art that the non-heating portions may extend in a curved line instead of in a straight line, or may extend in a form that combines a straight line and a curved line.

[0144] The first to sixth heat generating portions 410 to 460, the first to sixth non-heat generating portions 510 to 560, and the first to sixth connecting members (not shown) may all be made of the same material, but are not necessarily limited to this.

[0145] As described above, the 6-zone heating element according to an embodiment of the present invention has six non-heating parts with shorter linear lengths than conventional ones, thereby reducing thermal stress caused by the non-heating parts, and thus effectively reducing the occurrence of cracks in the area where the non-heating parts contact the ceramic plate. In addition, the 6-zone heating element can improve the temperature uniformity of the ceramic heater heating surface by independently controlling six regions of the ceramic heater heating surface to realize various temperature distributions.

[0146] Although the present invention has been described above with reference to specific embodiments, it is of course possible to make various modifications without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the embodiments described, but should be determined by the following claims and equivalents thereof.

Claims

1. A ceramic heater including a two-zone heating element, The two-zone heating element is A first heating portion and a second heating portion that can be independently controlled by a power supply device; a first non-heating portion disposed between first and second sub-heating portions constituting the first heat generating portion and electrically connecting the first and second sub-heating portions; a second non-heating portion disposed between the second heat-generating portion and a first electrode terminal, electrically connecting the second heat-generating portion and the first electrode terminal.

2. The first sub-heating portion is formed at a position corresponding to a center zone of a heating surface of the ceramic heater, The second sub-heating portion is formed at a position corresponding to an edge zone of the heating surface of the ceramic heater, The ceramic heater according to claim 1, wherein the second heating portion is formed at a position corresponding to a middle zone of the heating surface of the ceramic heater.

3. the first non-heating portion is formed to have a first length that is shorter than or equal to a straight line length between a point of the second sub-heating portion and a second electrode terminal connected to the first sub-heating portion; The ceramic heater according to claim 1, wherein the second non-heating portion is formed to have a second length that is shorter than or equal to a straight line length between a point of the second sub-heating portion and the first electrode terminal.

4. The first non-heating portion is formed to extend in a straight line or a curved line from a point of the first sub-heating portion to a point of the second sub-heating portion, The ceramic heater according to claim 1, wherein the second non-heating portion extends in a straight line or a curved line from the first electrode terminal to a point on the second heating portion.

5. The first non-heating part is connected to the second sub-heating part through a first connector, The ceramic heater according to claim 1 , wherein the second non-heating portion is connected to the second heating portion through a second connecting member.

6. 2. The ceramic heater according to claim 1, wherein the first and second non-heating portions are disposed on a straight line that crosses a center of the two-zone heating element.

7. 2. The ceramic heater according to claim 1, wherein the first and second non-heating portions are disposed opposite each other with respect to a center of the two-zone heating element.

8. 2. The ceramic heater according to claim 1, wherein the first and second non-heating portions include two metal wires arranged parallel to each other, and an axis of symmetry between the two metal wires crosses a center of the two-zone heating element.

9. A ceramic heater including a four-zone heating element, The four-zone heating element comprises: First to fourth heating units that can be independently controlled by a power supply device; a first non-heating portion and a second non-heating portion disposed opposite each other with respect to a first axis of symmetry between the first heating portion and the second heating portion and disposed at a certain distance from the center of the 4-zone heating element; and third and fourth non-heating portions disposed opposite each other with respect to a second axis of symmetry between the third and fourth heating portions, and extending from first and second electrode terminals disposed at a center of the four-zone heating element toward the third and fourth heating portions.

10. The ceramic heater according to claim 9, wherein the second axis of symmetry is perpendicular to the first axis of symmetry.

11. 10. The ceramic heater of claim 9, wherein the first and second axes of symmetry pass through a center of the four-zone heating element.

12. the first non-heating portion is disposed between first and second sub-heating portions constituting the first heat generating portion and electrically connects the first and second sub-heating portions; the second non-heating portion is disposed between third and fourth sub-heating portions constituting the second heat generating portion and electrically connects the third and fourth sub-heating portions; the third non-heat generating portion is disposed between the third heat generating portion and the first electrode terminal and electrically connects the third heat generating portion and the first electrode terminal; 10. The ceramic heater according to claim 9, wherein the fourth non-heating portion is disposed between the fourth heat-generating portion and the second electrode terminal and electrically connects the fourth heat-generating portion and the second electrode terminal.

13. the first non-heating portion is formed to have a first length that is shorter than or equal to a straight line length between a point of the second sub-heating portion and a third electrode terminal connected to the first sub-heating portion; the second non-heating portion is formed to have a first length that is shorter than or equal to a straight line length between a point of the fourth sub-heating portion and a fourth electrode terminal connected to the third sub-heating portion, the third non-heating portion is formed to have a second length that is shorter than or equal to a straight line length between one point of the second sub-heating portion or the fourth sub-heating portion and the first electrode terminal; 13. The ceramic heater according to claim 12, wherein the fourth non-heating portion is formed to have a second length that is shorter than or equal to a straight line length between a point of any one of the second sub-heating portion and the fourth sub-heating portion and the second electrode terminal.

14. The ceramic heater according to claim 9, wherein each of the first to fourth non-heat generating portions is formed to extend in a straight line or a curved line.

15. The ceramic heater according to claim 9, wherein the first to fourth non-heating parts are connected to the first to fourth heating parts through connecting members, respectively.

16. A ceramic heater including a 6-zone heating element, The six-zone heating element comprises: First to sixth heating units that can be independently controlled by a power supply device; First to third non-heating sections are disposed at a certain distance from the center of the 6-zone heating element and are disposed at an angle of 120° with respect to the center of the 6-zone heating element; and fourth to sixth non-heating portions extending from first to third electrode terminals disposed at a center of the six-zone heating element toward fourth to sixth heating portions and disposed at an angle of 120° with respect to the center of the six-zone heating element.

17. the first non-heating portion is disposed between the first and second sub-heating portions constituting the first heat generating portion and electrically connects the first and second sub-heating portions; the second non-heating portion is disposed between the third and fourth sub-heating portions constituting the second heat generating portion and electrically connects the third and fourth sub-heating portions; the third non-heating portion is disposed between the fifth and sixth sub-heating portions constituting the third heat generating portion, and electrically connects the fifth and sixth sub-heating portions; the fourth non-heat generating portion is disposed between the fourth heat generating portion and the first electrode terminal and electrically connects the fourth heat generating portion and the first electrode terminal; the fifth non-heat generating portion is disposed between the fifth heat generating portion and the second electrode terminal and electrically connects the fifth heat generating portion and the second electrode terminal; The ceramic heater according to claim 16, wherein the sixth non-heating portion is disposed between the sixth heat-generating portion and the third electrode terminal and electrically connects the sixth heat-generating portion and the third electrode terminal.

18. the first non-heating portion is formed to have a first length that is shorter than or equal to a straight line length between a point of the second sub-heating portion and a fourth electrode terminal connected to the first sub-heating portion; the second non-heating portion is formed to have a first length that is shorter than or equal to a straight line length between a point of the fourth sub-heating portion and a fifth electrode terminal connected to the third sub-heating portion; the third non-heating portion is formed to have a first length that is shorter than or equal to a straight line length between a point of the sixth sub-heating portion and a sixth electrode terminal connected to the fifth sub-heating portion; the fourth non-heating portion is formed to have a second length that is shorter than or equal to a straight line length between one point of any one of the second, fourth, and sixth sub-heating portions and the first electrode terminal; the fifth non-heating portion is formed to have a second length that is shorter than or equal to a straight line length between one point of any one of the second, fourth, and sixth sub-heating portions and the second electrode terminal; 18. The ceramic heater according to claim 17, wherein the sixth non-heating portion is formed to have a second length that is shorter than or equal to a straight line length between a point of any one of the second, fourth, and sixth sub-heating portions and the third electrode terminal.

19. The ceramic heater according to claim 16, wherein each of the first to sixth non-heat generating portions is formed to extend in a straight line or a curved line.

20. The ceramic heater according to claim 16, wherein the first to sixth non-heating parts are connected to the first to sixth heating parts through connecting members, respectively.

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