SiC heater

Abstract

We provide SiC heaters with a highly durable insulating coating. [Solution] The heating element comprises a thin plate-shaped silicon carbide sintered body and an insulating coating formed on the surface of the silicon carbide sintered body, a pair of electrodes for supplying current to the heating element, and a heater base that holds the heating element from one side while insulating heat from the heating element, wherein the insulating coating is located on the side of the silicon carbide sintered body opposite to the heater base, and the electrical resistance of the insulating coating at room temperature is 10 9 A SiC heater having a density of Ω or more, wherein the insulating coating comprises a matrix consisting of SiO2 and either Al2O3 or B2O3, or both, and a component added to the matrix, the component being at least one selected from the group consisting of zinc oxide, gallium oxide, magnesium oxide, and tin oxide, and the total content of the component being greater than 5.0% by mass and less than or equal to 30.0% by mass of the entire insulating coating.

Description

[Technical Field]

[0001] This invention relates to a SiC heater. [Background technology]

[0002] In recent years, development toward high integration, such as 2.5D and 3D mounting, has been accelerating, particularly in smartphones, mobile phones, and tablet devices. For the mounting of SoCs (System-on-a-Chip) components like memory and application processors, reflow soldering, which involves the continuous thermal treatment of multiple devices simultaneously, remains the dominant method. However, reflow soldering has limitations in terms of bump fineness and gap narrowing, making further high integration difficult. Therefore, a mounting method called thermocompression bonding is attracting attention as an alternative to reflow soldering and is already being put into practical use in some areas.

[0003] Thermocompression bonding is a mounting method that involves applying a load to each chip using a heater equipped with a heating element, followed by heating and cooling to achieve the desired mounting. It is known that using ceramic heating elements in the heaters that implement thermocompression bonding suppresses deformation of the heating elements when a load is applied, enabling high-precision mounting. For this reason, it is expected that thermocompression bonding using ceramic heaters with ceramic heating elements will become the mainstream mounting method in the future.

[0004] As a ceramic heater, a SiC heater using silicon carbide as the heating element is described in Patent Document 1. In this SiC heater, an insulating coating made of borosilicate glass or aluminosilicate glass is provided on the surface of the heating element made of silicon carbide. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Patent No. 3710690 [Overview of the project] [Problems that the invention aims to solve]

[0006] In recent years, manufacturing processes that involve applying higher loads than conventional methods to the thermocompression bonding method have been considered. Therefore, the SiC heaters used in these processes need to be durable enough to withstand high loads without damaging the insulating coating.

[0007] This invention has been made in view of these circumstances, and aims to provide a SiC heater equipped with a highly durable insulating coating. [Means for solving the problem]

[0008] To solve the above problems, one aspect of the present invention includes the following aspects.

[0009] [1] A heating element comprising a thin plate-shaped silicon carbide sintered body and an insulating coating formed on the surface of the silicon carbide sintered body, a pair of electrodes for supplying current to the heating element, and a heater base that holds the heating element from one side while insulating heat from the heating element, wherein the insulating coating is located on the side of the silicon carbide sintered body opposite to the heater base, and the electrical resistance of the insulating coating at room temperature is 10 9 The impedance is Ω or greater, and the insulating coating is made of SiO2, Al2O3 and B2O [3]のいずれか A SiC heater comprising a matrix consisting of one or both of the above, and a component added to the matrix, wherein the component is at least one selected from the group consisting of zinc oxide, gallium oxide, magnesium oxide, and tin oxide, and the total content of the component is greater than 5.0% by mass and less than or equal to 30.0% by mass of the entire insulating film.

[0010] [2] The SiC heater according to [1], comprising zinc oxide as the component.

[0011] [3] The SiC heater according to [1], comprising zinc oxide and magnesium oxide as the components.

[0012] [4] The SiC heater according to any one of [1] to [3], wherein the content rate of the calcium component in the insulating film is not more than the detection lower limit value by ICP spectroscopic analysis.

[0013] [5] The SiC heater according to any one of [1] to [4], wherein the content rate of the sodium component in the insulating film is not more than the detection lower limit value by ICP spectroscopic analysis.

[0014] [6] The shape of the heating element is a substantially S-shaped in plan view having two slits each cut from two opposite sides of a substantially square or substantially rectangular shape in plan view toward the opposite sides, and one of the pair of electrodes is connected to each of both ends of the substantially S-shaped. The SiC heater according to any one of [1] to [5].

[0015] [7] The combined density of the silicon carbide sintered body is 2.5 g / cm 3 or more, and the electrical resistivity at 25 ° C is 0.1 Ω·cm or more and 100 Ω·cm or less. The SiC heater according to any one of [1] to [6].

Effect of the Invention

[0016] According to the present invention, it is possible to provide a SiC heater provided with an insulating film having high durability.

Brief Description of the Drawings

[0017] [Figure 1] It is a cross-sectional view of a heating element of a SiC heater according to an embodiment of the present invention. [Figure 2] It is a perspective view showing a heating element of a SiC heater according to an embodiment of the present invention. [Figure 3] It is a front view showing a SiC heater according to an embodiment of the present invention. [Figure 4] It is a bottom plan view showing a SiC heater according to an embodiment of the present invention. [Figure 5] It is a top plan view showing a SiC heater according to an embodiment of the present invention. [Figure 6]This is a side view showing a SiC heater according to one embodiment of the present invention. [Figure 7] This is a front cross-sectional view (a cross-sectional view along line AA shown in Figure 4) showing the state of bonding semiconductor chips using a SiC heater according to one embodiment of the present invention. [Figure 8] This is a side cross-sectional view (a cross-sectional view along the line BB shown in Figure 4) showing the state of bonding semiconductor chips using a SiC heater according to one embodiment of the invention. [Figure 9] This is a side cross-sectional view (a cross-sectional view along the CC line shown in Figure 4) taken from an oblique direction, showing the state of bonding semiconductor chips using a SiC heater according to one embodiment of the invention. [Figure 10] This is a perspective view showing the manufacturing process using a flip-chip bonder with a SiC heater according to one embodiment of the invention. [Modes for carrying out the invention]

[0018] The following describes one embodiment of the present invention in detail. However, this embodiment is provided to give a better understanding of the spirit of the invention and does not limit the scope of the invention unless otherwise specified. Changes, omissions, additions, and other modifications to the number, position, size, etc., are possible without departing from the spirit of the present invention.

[0019] [SiC heater] Figures 1 and 2 are cross-sectional and perspective views, respectively, of the heating element 1 of the SiC heater 100 in this embodiment. Figures 3 to 6 are front, bottom, top, and side views, respectively, of the SiC heater 100 in this embodiment.

[0020] As shown in Figures 3 to 6, the SiC heater 100 of this embodiment comprises a heating element 1, a pair of electrodes 20, 20, a heater base 21, and a cooling system connecting member 22. The pair of electrodes 20, 20 are energized through the heating element 1. The heater base 21 holds the heating element 1 from one side while insulating it from the heat. The cooling system connecting member 22 supports the heater base 21. The electrodes 20 have lead wires 24 and bolts 16 for fixing the lead wires 24 to the heating element 1. The following provides a detailed explanation of each part.

[0021] [Heating element] As shown in Figure 1, the heating element 1 has a thin plate-shaped silicon carbide sintered body 1A and an insulating coating 1B formed on the surface of the silicon carbide sintered body.

[0022] As shown in Figure 2, the heating element 1 is a thin plate that is approximately square or rectangular. In this embodiment, the approximately square or rectangular shape is defined as having first and second sides that face each other, and third and fourth sides that are connected to the first and second sides at the corners and face each other. As an example, the heating element 1 is a thin plate with an outer diameter of 22 mm and a thickness of 1 mm. The heating element 1 has an adsorption surface 1a that is the side that adsorbs the chip and is located opposite the heater base 21, and a back surface 1b that is located on the heater base 21 side.

[0023] The heating element 1 has a roughly S-shape with two slits 2 and 3 (also called the first slit 2 and the second slit 3) cut from two opposing sides (i.e., the first and second sides) toward the opposite side. The two slits 2 and 3 are roughly parallel to each other and roughly parallel to the third and fourth sides. The length of the slits 2 and 3 is 2 / 3 of the length of the third and fourth sides. Electrodes 20 are connected to both ends of the roughly S-shape of the heating element 1 (also called the start and end points). The slits 2 and 3 absorb the effects of thermal expansion and contraction of the heating element 1 due to temperature changes. Therefore, by providing the slits 2 and 3, the heating element 1 can be made stronger against thermal stress. This makes it possible to form the heating element 1 with a thinner plate thickness, and as a result the heat capacity of the heating element 1 can be reduced, enabling rapid heating and cooling. In addition, by making the heating element 1 roughly S-shaped through the slits 2 and 3, the current flows through that path, improving the uniformity of the heating element 1.

[0024] The heating element 1 is provided with through holes 4 and 5 for electrode mounting, a through hole 6 for forming a gas passage for chip adsorption, through holes 7 and 8 and grooves 9 and 10 for forming a gas passage for heat transfer plate adsorption, through holes 11 and 12 for forming an inert gas passage, and through holes 13 and 14 for inserting countersunk screws 15 and 15 for fixing the heating element 1 to the heater base 21.

[0025] The through holes 4 and 5 for electrode mounting are located at the approximately S-shaped ends of the heating element 1 (i.e., the starting and ending points of the S-shape). The through hole 6 is located approximately in the center of the heating element 1. In other words, the through hole 6 is located approximately midway along the straight line connecting the through holes 4 and 5. The through holes 7 and 8 are located near the outer edges of the corners opposite the approximately S-shaped ends of the heating element 1. The grooves 9 and 10 are located on the adsorption surface 1a of the heating element 1, communicating with the through holes 7 and 8 respectively, and are formed in an approximately L-shape along the outer edge. The through hole 11 is located midway between the through hole 4 and the through hole 7. The through hole 12 is located midway between the through hole 5 and the through hole 8.

[0026] (Silicon carbide sintered body) The silicon carbide sintered body 1A of the heating element 1 is silicon carbide, particularly preferably silicon carbide with a sintered body density of 2.5 g / cm 3 or more, more preferably silicon carbide with a sintered body density of 3.15 / cm 3 or more. By setting the sintered body density of the silicon carbide sintered body 1A to 2.5 g / cm 3 or more, the bonding force between silicon carbide particles can be sufficiently obtained. Also, by setting the sintered body density of the silicon carbide sintered body 1A to 2.5 g / cm 3 or more, the mechanical strength at high temperatures can also be sufficiently ensured. Therefore, damage to the heating element 1 due to the load during bonding and plastic deformation at high temperatures can be suppressed, and a surface accuracy of several micrometers can be easily obtained.

[0027] The theoretical density of silicon carbide is 3.21 g / cm 3 Therefore, the sintered body density of the silicon carbide sintered body 1A in this embodiment is preferably 2.5 g / cm 3 or more and 3.21 g / cm 3 or less.

[0028] The silicon carbide sintered body 1A preferably has a thermal conductivity at room temperature of 100 W / m·K or more, more preferably 180 W / m·K or more. As described above, the sintered body density of the silicon carbide sintered body 1A is dense at 2.5 g / cm 3 or more. Also, since the silicon carbide sintered body 1A can be sintered without adding a sintering aid as described later, there are few impurities present at the grain boundaries, and a fine and uniform structure can be obtained. Due to these, the silicon carbide sintered body 1A can have a high thermal conductivity of 100 W / m·K or more. This silicon carbide sintered body 1A has excellent heat uniformity, has no connection failure in the bonding part, and has a high product yield. Furthermore, the time required for cooling is short, the bonding process time for one time is shortened, the cost performance is high, and there is no risk of damage due to thermal shock even during rapid temperature rise or rapid temperature drop. The thermal conductivity of the silicon carbide sintered body 1A at room temperature is preferably as high as possible, but is usually 260 W / m·K or less.

[0029] The electrical resistivity of silicon carbide sintered body 1A at room temperature (25°C) is preferably 0.1 Ω·cm or more and 100 Ω·cm or less, more preferably 0.2 Ω·cm or more and 70.0 Ω·cm or less, and even more preferably 10.0 Ω·cm or more and 60.0 Ω·cm or less.

[0030] By setting the electrical resistivity of the silicon carbide sintered body 1A to 0.1 Ω·cm or higher, the flow of large currents through the silicon carbide sintered body 1A can be suppressed. Therefore, the stress caused by electromagnetic induction in the lead wires 24 of the electrode 20 can be suppressed, thereby reducing the positional accuracy of the heater head. In addition, by setting the electrical resistivity of the silicon carbide sintered body 1A to 0.1 Ω·cm or higher, it becomes possible to sufficiently secure the resistance value of the silicon carbide sintered body 1A without thinning the heating element 1, and the bonding pressure (normally 50 kg / cm²) can be reduced. 2 It can be made strong enough to withstand (a certain degree).

[0031] Furthermore, by setting the electrical resistivity of the silicon carbide sintered body 1A to 100 Ω·cm or less, current can be passed without applying a high voltage, and since no special power supply is required, it is preferable.

[0032] (Insulating coating) The insulating coating 1B of the heating element 1 is provided at least on the side of the silicon carbide sintered body 1A opposite to the heater base 21 (adsorption surface 1a). The insulating coating 1B is made of a material described later. As shown in Figure 1, it is preferable that the insulating coating 1B is formed not only on the adsorption surface 1a but also on the back surface 1b and the sides of the heating element 1.

[0033] The thickness of the insulating film 1B is preferably 10 μm or more and 100 μm or less. Preferably, the thickness of the insulating film 1B is 20 μm or more and 80 μm or less, and more preferably 30 μm or more and 70 μm or less. The upper and lower limits of the range for the thickness of the insulating film 1B can be arbitrarily combined. If the thickness of the insulating film 1B is less than 10 μm, the insulating properties as a heater will be significantly reduced, and if it exceeds 100 μm, the insulating film 1B will easily peel off from the silicon carbide sintered body 1A due to internal strain with the SiC heater, which is undesirable. If the thickness of the insulating film 1B is 10 μm or more, the insulating properties as a heater can be ensured. Furthermore, by making the insulating film 1B 100 μm or less, the heat capacity of the insulating film 1B can be reduced, and the thermal conductivity from the silicon carbide sintered body 1A to the workpiece via the insulating film 1B can be increased, thereby increasing the response speed of the heater.

[0034] Insulating coating 1B has an electrical resistance of 10 at room temperature. 9 Preferably, it is Ω or more, 10 10 It is more preferable that the resistance be Ω or greater. This ensures reliable insulation between the heating element 1 and the workpiece (the chip to be heated) by the heating element 1. The electrical resistance of insulating coating 1B at room temperature is measured using an insulation resistance meter, specifically by applying a high voltage between the glass surface coated on the heater and the heater electrode.

[0035] To suppress damage caused by differences in thermal expansion, it is preferable that the thermal expansion coefficient of the insulating coating 1B is close to that of the silicon carbide sintered body 1A. The thermal expansion coefficient of the insulating coating 1B from 50°C to 350°C is 2 × 10⁻⁶. -6 / K or more 6×10 -6 It is preferable that it be less than or equal to / K, and 2.6 × 10 -6 / K or more 5.0×10 -6 It is more preferable that the temperature is below / K. The heating element 1 undergoes rapid heating and cooling many times. For this reason, the thermal expansion coefficient of the insulating coating 1B is set to the thermal expansion coefficient of the silicon carbide sintered body 1A, which is the base composition of the heating element 1 (approximately 3.7 × 10⁻¹⁰ from 50°C to 350°C). -6By bringing the temperature closer to / K, the peeling of the insulating coating 1B from the silicon carbide sintered body 1A can be suppressed. The thermal expansion coefficient of insulating film 1B is measured using a thermal expander. For example, a horizontal total expansion thermal expander (model number DIL402SU, manufactured by NETZSCH) can be used.

[0036] The insulating film 1B includes a matrix consisting of SiO2 and either Al2O3 or B2O3, or both. That is, the insulating film 1B may include a matrix consisting of SiO2 and Al2O3, a matrix consisting of SiO2 and B2O3, or a matrix consisting of SiO2, Al2O3, and B2O3.

[0037] The insulating film 1B, by including the matrix described above, can ensure sufficient insulation with the aforementioned electrical resistance. It should be noted that "the insulating film 1B has the above substance as its matrix" means that the substance indicated as the matrix is ​​the main component of the insulating film 1B. The matrix is ​​preferably 30.0% to 98.0% by mass, and more preferably 46.0% to 57.0% by mass, relative to the total mass of the insulating film 1B.

[0038] The insulating film 1B preferably contains SiO2 in an amount of 30.0% by mass or more and less than 93.0% by mass relative to the total mass of the insulating film 1B, and more preferably 30.0% by mass or more and 50.0% by mass or less. By having an SiO2 content of 30.0% by mass or more and less than 93.0% by mass in the insulating film 1B, a stable glass network structure can be created, and it can function as a matrix.

[0039] When the insulating film 1B contains Al2O3, it is preferable that the insulating film 1B contains 20.0% by mass or more of Al2O3 relative to the total mass of the insulating film 1B, more preferably 22.0% by mass or more, more preferably 25.0% by mass or more, and even more preferably 30.0% by mass or more. Furthermore, the Al2O3 content in the total mass of the insulating film 1B is preferably 50.0% by mass or less, and more preferably 45.0% by mass or less. When the insulating film 1B contains Al2O3, an Al2O3 content of 20.0% by mass or more in the insulating film 1B results in thermal stability and excellent mechanical properties.

[0040] When insulating film 1B contains B2O3, it is preferable that insulating film 1B contains 2.0% by mass or more of B2O3 relative to the total mass of insulating film 1B, more preferably 5.0% by mass or more, and even more preferably 10.0% by mass or more. Furthermore, the B2O3 content in the total mass of insulating film 1B should be 20.0% by mass or less. When insulating film 1B contains B2O3, it becomes an insulating film with excellent chemical durability.

[0041] Furthermore, it is preferable that the amount of Al2O3 is greater than the amount of B2O3.

[0042] The insulating coating 1B contains at least one component selected from the group consisting of zinc oxide, gallium oxide, magnesium oxide, and tin oxide as an additive to the matrix. Among these, the component added to the matrix preferably contains zinc oxide. Furthermore, the component added to the matrix preferably contains both zinc oxide and magnesium oxide.

[0043] The total content of the above components is greater than 5.0% by mass and less than or equal to 30.0% by mass of the entire insulating film 1B (total mass). When the content of the above components is within the above range, crystallization of the insulating film 1B is suppressed, and it is thought that the film is less likely to crack even during long-term use. In addition, since the thermal expansion coefficient of the insulating film 1B approaches that of SiC, it is thought to have excellent long-term stability.

[0044] The content of the above components is preferably 5.0% by mass or more and 30.0% by mass or less, and more preferably 10.0% by mass or more and 20.0% by mass or less, based on the total mass of the insulating film 1B.

[0045] When the above component is zinc oxide, the zinc oxide content is preferably 5.0% by mass or more and 10.0% by mass or less based on the total mass of the insulating film 1B.

[0046] When magnesium oxide is included as one of the above components, the magnesium oxide content is preferably 5.0% by mass or more and 10.0% by mass or less relative to the total mass of the insulating coating 1B. Insulating coating 1B containing magnesium oxide tends to be less prone to cracking even when heat is applied. It is thought that the structure of the insulating coating is stabilized by the inclusion of magnesium oxide (Mg atoms) in insulating coating 1B.

[0047] When gallium oxide is included as one of the above components, the gallium oxide content is preferably 5.0% by mass or more and 10.0% by mass or less based on the total mass of the insulating film 1B.

[0048] When the above components include tin oxide, the tin oxide content is preferably 5.0% by mass or more and 10.0% by mass or less based on the total mass of the insulating film 1B.

[0049] On the other hand, it is preferable that the insulating coating 1B contains as little sodium (Na), calcium (Ca), and barium (Ba) as possible. For example, it is preferable that the Na content in the insulating coating 1B is below the detection limit in elemental analysis by ICP emission spectrometry. For example, in the elemental analysis employed in this embodiment, the detection limits for each element are as follows. B:20ppm, Al:5ppm, Zn:5ppm, Mg:5ppm, Ca:5ppm, Ba:10ppm, Na:200ppm

[0050] The Ca content in insulating film 1B is preferably less than 5 ppm, and more preferably below the detection limit in elemental analysis.

[0051] The Ba content in insulating film 1B is preferably less than 5 ppm, and more preferably below the detection limit in elemental analysis.

[0052] The "Na content" mentioned above refers to the NaO content calculated based on the Na content obtained from elemental analysis of the insulating film, assuming that all the Na contained in the insulating film is Na oxide (NaO). The same applies to the Ca and Ba components.

[0053] The Na and Ca contained in the insulating coating can move within the film in an ionic state when heated, potentially reducing the stability of the insulating coating and causing cracks. Furthermore, the elution of the moving Na and Ca onto the surface of the insulating coating may contaminate semiconductor chips processed by the thermocompression bonding method. Additionally, the Ba contained in the insulating coating increases the ionic mobility of Na and Ca. Therefore, by keeping the Na, Ca, and Ba content in insulating coating 1B below 5 ppm, crack formation can be suppressed even when heat is applied.

[0054] (Middle class) The heating element 1 may have an intermediate layer (not shown) at the interface between the silicon carbide sintered body 1A and the insulating coating 1B. The intermediate layer is an oxide film formed on the surface of the silicon carbide sintered body 1A, and can be formed by ozone treatment or corona discharge treatment on the surface of the silicon carbide sintered body 1A where the insulating coating 1B is formed. Alternatively, an SiO2 film may be formed on the surface of the silicon carbide sintered body 1A by physical vapor deposition (PVD) or chemical vapor deposition (CVD) to serve as the intermediate layer.

[0055] Furthermore, a primer layer using a silane coupling agent or the like may be formed on the surface of the silicon carbide sintered body 1A, and this layer may serve as an intermediate layer.

[0056] As a silane coupling agent, it is best to select one that adheres well to the insulating film to be formed. For example, as silane coupling agents, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2-(Amm Noethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatetopropyltriethoxysilane, etc. can be used.

[0057] The silane coupling agent may be used directly (without dilution), or it may be used after being appropriately diluted with an organic solvent such as alcohol. Furthermore, a silane coupling agent may be used in which a small amount of water and acid have been added to partially accelerate hydrolysis.

[0058] A single silane coupling agent may be used, or two or more may be used in combination.

[0059] The intermediate layer facilitates the wetting and spreading of the insulating film 1B material when forming the insulating film 1B on the surface of the silicon carbide sintered body 1A. This makes the formation of the insulating film 1B easier.

[0060] The thickness of the intermediate layer is preferably, for example, 0.2 μm or more and 2 μm or less, and more preferably 0.5 μm or more and 1.5 μm or less.

[0061] 〔electrode〕 The electrode 20 has a lead wire 24 and a bolt 16. The bolt 16 is inserted through through holes 4 and 5 located at the approximately S-shaped ends of the heating element 1 to fix the lead wire 24 to the heating element 1. It is preferable that the electrode 20 fixed to the heating element 1 be arranged so that the current flows more uniformly over the entire surface of the heating element 1, according to the shape of the heating element 1.

[0062] [Heater base] The heater base 21 is located between the cooling system connecting member 22 and the heating element 1. The heater base 21 holds the heating element 1 with the chip-adsorption side (grooved side) facing downwards. The heater base 21 holds the heating element 1 using countersunk screws 15, 15 which are inserted through the through holes 13, 14 of the heating element 1, respectively.

[0063] The heater base 21 is made of an insulating ceramic material with high thermal insulation properties and excellent thermal shock resistance. Examples of ceramic materials used in the heater base 21 include silicon nitride (Si3N4), calcium silicate (CaO·SiO2), and SiAlON.

[0064] The heater base 21 holds the heating element 1 from one side, thus suppressing heat loss through the heater base 21 when the heating element 1 is heated. This makes it possible to rapidly heat the heating element 1 with a small input power. In addition, since heat loss to the cooling system connection member 22 to which the heater base 21 is attached is reduced, displacement of the heater due to thermal expansion of the cooling system connection member 22 can be suppressed. Furthermore, since the heater base 21 mechanically reinforces the heating element 1 from one direction, damage to the heating element 1 due to the load during bonding can be suppressed.

[0065] As shown in Figure 6, a counterbore (also called a recess) 21a is provided on the surface of the heater base 21 that is in contact with the heating element 1. The counterbore 21a is provided in areas other than those where insulation is required between the heating element 1 and the heater base 21. In other words, because the counterbore 21a is provided, the heating element 1 and the heater base 21 do not come into contact with each other except in areas where insulation is required. In addition, the gap formed by the counterbore 21a functions as a passage for cooling gas.

[0066] [Cooling system connection components] As shown in Figures 3, 4, and 6, the cooling system connecting member 22 supports the heating element 1 via the heater base 21. The cooling system connecting member 22 is fixed to the heater base 21 by a pair of bolts 23, 23.

[0067] As shown in Figure 5, the surface of the cooling system connecting member 22 opposite to the heater base 21 (upper surface 22a) is formed as a flat surface. The SiC heater 100 is fixed to the heater mounting part on the bonding device side, such as a flip-chip bonder, via the upper surface 22a. The upper surface 22a is provided with four through holes 28, ..., 28 for screw fastening to the heater mounting part.

[0068] Figures 7 to 9 show the state of joining semiconductor chips using a SiC heater. Figure 7 is a cross-sectional view along line AA in Figure 4, showing the state of joining semiconductor chips using a SiC heater according to one embodiment of the present invention. Figure 8 is a cross-sectional view along line BB in Figure 4, showing the state of joining semiconductor chips using a SiC heater according to one embodiment of the present invention. Figure 9 is a cross-sectional view along line CC in Figure 4, showing the state of joining semiconductor chips using a SiC heater according to one embodiment of the present invention.

[0069] As shown in Figure 7, the cooling system connecting member 22 and the heater base 21 are provided with through-holes (chip adsorption through-holes) 31 that penetrate the heater base 21 and the cooling system connecting member 22 concentrically with the through-hole 6 of the heating element 1. A negative pressure generating device (not shown) is connected to the through-hole 31, and it adsorbs chips at the through-hole 6 of the heating element 1.

[0070] As shown in Figure 8, the cooling system connecting member 22 and the heater base 21 are provided with through-holes (through-holes for supplying various gases) 32 and 33 that penetrate the heater base 21 and the cooling system connecting member 22 concentrically with the through-holes 11 and 12 of the heating element 1. The through-holes 32 and 33 serve as passages for various gases, such as nitrogen gas, to be supplied when bonding is performed using the SiC heater 100 in an inert gas atmosphere.

[0071] As shown in Figure 9, the cooling system connecting member 22 and the heater base 21 are provided with through-holes (through-holes for heat transfer plate adsorption on the groove side) 35 and 36 that penetrate the heater base 21 and the cooling system connecting member 22 concentrically with the through-holes 7 and 8 of the heating element 1. Also, as shown in Figure 5, the cooling system connecting member 22 is provided with a pair of grooves 26. The through-holes 35 and 36 open upwards in the pair of grooves 26. The through-holes 35 and 36 form gas passages for heat transfer plate adsorption.

[0072] As shown in Figure 9, the cooling system connecting member 22 and the heater base 21 are provided with through holes 37 and 38 that penetrate the heater base 21 and the cooling system connecting member 22 at positions that communicate with the counterbore portion 21a of the heater base 21. Also, as shown in Figure 5, the cooling system connecting member 22 is provided with a pair of grooves 27. The through holes 37 and 38 open upwards in the pair of grooves 27. The through holes 37 and 38 form an air supply passage that supplies cooling gas to the counterbore portion 21a to rapidly cool the heating element 1. The cooling gas supplied from the through holes 37 and 38 passes through the counterbore portion 21a formed on the surface of the heater base 21 on the side of the heating element 1, cools the back surface of the heating element 1, and then exits to the outside from the side surface of the heater base 21. Alternatively, the cooling gas supplied from the through holes 37 and 38 passes through the slits 2 and 3 via the counterbore portion 21a, cools the heating element 1, and then exits from the side surface of the heating element 1.

[0073] By forming a recessed portion 21a on the surface of the heater base 21 facing the heating element 1, a gap is created between the heating element 1 and the heater base 21, and slits 2 and 3 are formed in the heating element 1. As a result, when cooling with a cooling gas, the recessed portion 21a increases the surface area in contact with the cooling gas between the heating element 1 and the heater base 21, thereby increasing the cooling efficiency. Moreover, since the slits 2 and 3 in the heating element 1 are in communication with the recessed portion 21a, the cooling gas can also pass through the slits 2 and 3, increasing the cooling rate and enabling rapid cooling.

[0074] [Method for manufacturing a heating element] Next, the manufacturing method for the heating element 1 will be described. The heating element 1 of this embodiment has a sintered body density of 2.5 g / cm³. 3The present invention provides a silicon carbide sintered body 1A with an electrical resistivity of 0.1 to 100 Ω·cm. Such a silicon carbide sintered body 1A is obtained by mixing a first silicon carbide powder with an average particle size of 0.1 to 10 μm and a second silicon carbide powder with a particle size of 0.1 μm or less, and then sintering the mixture. This method makes it easy to obtain silicon carbide exhibiting an electrical resistivity in the range of 0.1 to 100 Ω·cm. A method for manufacturing such a silicon carbide sintered body 1A is disclosed in Japanese Patent Application Publication No. 4-65361, but in this embodiment, it is desirable to use silicon carbide with a large electrical resistivity of 0.1 to 100 Ω·cm.

[0075] To produce the silicon carbide sintered body 1A having the above-described characteristics, first, a first silicon carbide powder with an average particle size of 0.1 to 10 μm and a second silicon carbide fine powder with an average particle size of 0.1 μm or less are prepared. The average particle sizes of the first and second silicon carbide powders are determined using a laser diffraction particle size distribution analyzer.

[0076] The first silicon carbide powder can be any commonly used type, such as one produced by the silica reduction method or the Acheson process. The crystalline phase of the first silicon carbide powder can be amorphous, α-type, or β-type, but the α-type is preferred because it is easy to adjust the electrical resistivity to 0.1 to 100 Ω·cm.

[0077] The second silicon carbide powder is obtained by introducing a raw material gas consisting of a silane compound or silicon halide and hydrocarbons into a plasma in a non-oxidizing atmosphere, and carrying out a gas-phase reaction while controlling the pressure of the reaction system from less than 1 atmosphere to 0.1 torr (where 1 torr = 133.3 Pa). The crystalline phase of the second silicon carbide powder may be amorphous, α-type, or β-type. Because the second silicon carbide powder obtained in this way has excellent sinterability, a high-purity and dense silicon carbide sintered body 1A can be obtained simply by mixing it with the first silicon carbide powder without adding any sintering aids.

[0078] Next, the first silicon carbide powder and the second silicon carbide powder are mixed to form a mixture. The mixing ratio is determined in advance by preliminary experiments so that the resulting silicon carbide sintered body has a predetermined electrical specific low resistance value (0.1 to 100 Ω·cm). Then, the mixture is molded into the desired shape, and the resulting molded body is sintered at a temperature of 1800 to 2400°C to obtain a sintered body, which is designated as silicon carbide sintered body 1A. Neither the sintering method nor the atmosphere during sintering is limited, but examples include sintering using a hot press furnace in a non-oxidizing atmosphere.

[0079] Next, an insulating film 1B is formed on the surface of the silicon carbide sintered body 1A. The insulating film 1B is formed by the following method. First, the surface of the processed silicon carbide sintered body 1A is ultrasonically cleaned with acetone and then air-dried. After that, the silicon carbide sintered body 1A may be heat-treated in an oxidation furnace, for example, at a temperature of 1000°C for 70 hours, to form a sufficient oxide film (intermediate layer) on the surface of the silicon carbide sintered body 1A.

[0080] Next, a paste is formed by mixing glass powder (matrix) having the desired composition, components to be added to the matrix, and terpineol.

[0081] The matrix composition may be adjusted, for example, by using high-purity (3N or higher) silicon oxide glass as a base and adding either or both Al2O3 and B2O3. Similarly, the matrix composition may be adjusted by using high-purity borosilicate glass or aluminosilicate glass as a base and adding SiO2, Al2O3, and B2O3.

[0082] Next, paste is applied to the surface of the silicon carbide sintered body 1A that is in contact with the heater base (back surface 1b), the opposite surface (adsorption surface 1a), and the side surface, and then dried in a drying oven at, for example, 100°C for 1 hour.

[0083] The method of applying the paste is not particularly limited, and known methods such as spray coating, inkjet coating, dispenser coating, nozzle coating, bar coating, spin coating, dip coating, roll coating, screen printing, flexographic printing, gravure coating, slit coating, flow coating, screen printing, blade coating, and knife coating can be used.

[0084] In addition, other methods may be used as long as they allow for the proper formation of a paste coating.

[0085] Next, the paste is heated in an oxidation furnace, for example, at 900°C for 30 minutes. Upon heating, the terpineol contained in the paste evaporates or disappears, and the glass powder and additives contained in the paste melt and spread across the surface of the silicon carbide sintered body 1A. At this time, if an intermediate layer is formed on the surface of the silicon carbide sintered body 1A, the wetting and spreading of the molten material is promoted.

[0086] After heating is complete, the molten material solidifies upon cooling, forming an insulating coating 1B welded to the silicon carbide sintered body 1A. As a further finishing step, the surface of the formed insulating coating 1B is ground to make the parallelism of the upper and lower surfaces (adsorption surface 1a and back surface 1b) of the heating element 1, for example, 3 μm or less.

[0087] The parallelism of the upper and lower surfaces of the heating element 1 is calculated by measuring nine points with a dial gauge.

[0088] [Methods for bonding semiconductor chips] Figure 10 is a perspective view showing the manufacturing state using a flip-chip bonder with a SiC heater according to one embodiment of the invention. Based on Figure 10, a semiconductor chip bonding method using the SiC heater 100 of this embodiment will be described.

[0089] As shown in Figure 10, the SiC heater 100 is attached to the lower end of the movable base 210 of the flip-chip bonder 200 and used for manufacturing semiconductor mounting boards.

[0090] First, the SiC heater 100 moves the movable base 210 to the position of the autoloader 230 on which the tray 220 containing multiple semiconductor chips 40 is placed, and sucks air through the through hole 6 to pick up one semiconductor chip 40 from the tray 220.

[0091] Next, the movable stand 210 is moved to the position where the substrate 50 is prepared, and the semiconductor chip 40 is placed on the conductive bonding material 60 that has been pre-placed on the substrate 50 as shown in Figures 7 to 9. Furthermore, while applying downward pressure with the movable stand 210, the SiC heater 100 is energized to heat the heating element 1, and the semiconductor chip 40, conductive bonding material 60, and substrate 50 are heated almost uniformly via the heat transfer plate 30. As a result, the conductive bonding material 60 melts in a few seconds, and the substrate 50 and the semiconductor chip 40 are bonded together by the molten conductive bonding material 60.

[0092] When bonding is performed in an inert gas atmosphere, the inert gas supplied from the through holes 32 and 33 is blown out towards the side where the conductive bonding material is to be placed while bonding is being carried out.

[0093] After the bonding between the substrate 50 and the semiconductor chip 40 is complete, compressed air is supplied to the counterbore portion 21a through the through holes 37 and 38. The compressed air flows out from the back surface 1b side of the heating element 1 through the slits 2 and 3 to the outside of the SiC heater 100. The heating element 1 is rapidly cooled by the compressed air. After the conductive bonding material 60 has cooled and solidified, the suction of the semiconductor chip 40 is released and the movable stage 210 is moved upward. By supplying a high-pressure compressed gas such as compressed air for cooling, the heating element 1 can be rapidly cooled in a few seconds, thus protecting the semiconductor chip 40 and the substrate 50 from overheating and shortening the bonding process time for one cycle.

[0094] Next, the movable platform 210 is moved to the position of the autoloader 230 to pick up a new semiconductor chip 40, and flip-chip bonding is performed continuously onto the next substrate 50.

[0095] The heat transfer plate 30 used in the manufacture of this semiconductor chip mounting board is used to uniformly transfer heat from the heating element 1 to the semiconductor chip 40, conductive bonding material 60, and substrate 50. Therefore, the heat transfer plate 30 must have excellent heat conductivity, heat resistance, and thermal shock resistance. The heat transfer plate 30 is preferably made of ceramic, such as aluminum nitride (AlN).

[0096] Examples of conductive bonding materials 60 include solder bumps and gold bumps. Such bonding materials have the property of melting when heated and solidifying when cooled.

[0097] Since the heating element 1 is required to rapidly raise and lower its temperature, it is preferable that it has a small heat capacity. Therefore, in order to reduce the heat capacity while maintaining the mechanical strength of the heating element 1, the thickness of the heating element 1 is preferably about 0.5 to 1.5 mm, and more preferably 0.8 to 1.2 mm.

[0098] According to the bonding method using a SiC heater in this embodiment, the semiconductor chip 40, conductive bonding material 60, and substrate 50 are heated and pressurized by the heat from the heating element 1, resulting in rapid heating that melts the conductive bonding material 60 in a few seconds. Therefore, overheating of the semiconductor chip 40 and substrate 50 can be suppressed.

[0099] A SiC heater with the above-described configuration has an insulating coating, resulting in a SiC heater with a highly durable insulating coating.

[0100] Although embodiments of the present invention have been described above, the configurations and combinations thereof in the embodiments are merely examples, and additions, omissions, substitutions, and other modifications are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited by the embodiments. [Examples]

[0101] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0102] [Sample preparation] The heating element for the SiC heater was manufactured as follows. First, using silicon tetrachloride and ethylene as raw material gases, plasma CVD was performed to obtain a particle with an average particle size of 0.01 μm and a BET specific surface area of ​​96 m². 2 A amorphous silicon carbide ultrafine powder was obtained in a quantity of / g.

[0103] This ultrafine silicon carbide powder is 5.0% by mass and commercially available α-type silicon carbide powder (average particle size 0.7 μm, BET specific surface area 13 m²). 2 95.0% by mass of ( / g) was dispersed in methanol and then mixed in a ball mill for 12 hours. The mixture was then dried, molded, and hot-pressed sintered.

[0104] The average particle size of amorphous silicon carbide ultrafine powder and α-type silicon carbide powder was measured using a laser diffraction particle size distribution analyzer SALD-2300 (manufactured by Shimadzu Corporation).

[0105] The BET specific surface area of ​​amorphous silicon carbide ultrafine powder and α-type silicon carbide powder was measured by gas adsorption using a BET specific surface area analyzer BELSORP-miniII (Microtrac Bell Co., Ltd.).

[0106] The sintering conditions were: under an argon atmosphere, sintering temperature 2200°C, and press pressure 39.23 MPa (400 kgf / cm²). 2 The time taken was 90 minutes. The density of the sintered body was 3.1 × 10⁻⁶. 3 kg / m 3 A silicon carbide sintered body was obtained with an electrical resistivity of 0.3 Ω·cm at room temperature (4-terminal method) and a thermal conductivity of 230 W / mK at room temperature (laser flash method). The obtained silicon carbide sintered body was a disc-shaped molded body with a diameter of 400 mm and a thickness of 12 mm.

[0107] The density of the sintered body was determined by measuring the true density (d0) of the sintered body using the Archimedes method, and expressing the ratio of this true density (d0) to the theoretical density (dt) (d0 / dt) as a percentage, which was defined as the relative density (%).

[0108] The electrical resistivity of the sintered body at room temperature was measured using the four-terminal method with a Loresta GX (manufactured by Mitsubishi Chemical Analytec Co., Ltd.). Specifically, after surface grinding the obtained silicon carbide sintered body, the resistivity was measured radially on the surface of the disc-shaped sintered body at 45° angles and 10 cm intervals.

[0109] The thermal conductivity of the sintered body at room temperature was measured using the laser flash method. Specifically, the sintered body was cut into a disc shape with a diameter of 10 mm and a thickness of 3 mm, and the thermal conductivity was calculated by irradiating the surface with laser light and measuring the temperature of the back surface with a radiation thermometer (laser flash method as specified in Japanese Industrial Standard JIS R 1611 "Method for measuring thermal diffusivity, specific heat capacity, and thermal conductivity of fine ceramics by flash method").

[0110] Next, by processing the silicon carbide sintered body, a thin sheet of silicon carbide sintered body was obtained, as shown in Figure 2, having a through-hole 6 with a diameter of 2 mm for semiconductor chip adsorption, through-holes 7 and 8 for heat transfer plate adsorption, and slits 2 and 3 with a width of 1 mm extending from the outer edge inward. The heater surface of the thin sheet was 22 × 22 mm in size, and its thickness t was 1.0 mm. Furthermore, through-holes 13 and 14 for screw fastening to the heater base 21 and through-holes 4 and 5 for electrode mounting were formed in this thin sheet. The through-hole 6 for semiconductor chip adsorption, the through-holes 7 and 8 for heat transfer plate adsorption, and the through-holes 11 and 12 for heat transfer plate separation were drilled coaxially with the through-holes 31, 32, 33, 35, and 36 drilled in the heater base 21, which will be described later.

[0111] The thermal expansion coefficient of the obtained silicon carbide sintered body at 50°C to 350°C is 3.7 × 10⁻⁶. -6 The temperature was / K. The coefficient of thermal expansion was measured using a thermal expander. A horizontal total expansion thermal expander (model number DIL402SU, manufactured by NETZSCH) was used.

[0112] Next, a surface treatment was performed to form an insulating coating on the surface of the thin sheet made of the silicon carbide sintered body produced through the process described above. The procedure for forming the insulating coating is described in more detail below.

[0113] First, the surface of a thin sheet made of silicon carbide sintered body was ultrasonically cleaned with acetone and then air-dried. After that, it was heat-treated in an oxidation furnace at a temperature of 1000°C for 70 hours to generate a sufficient oxide film (intermediate layer).

[0114] Next, an insulating coating material, in which the composition of glass powder and each additive component was appropriately adjusted to the composition shown in Table 1 below, was thoroughly mixed with terpineol in a 3:2 ratio using a planetary mixer to prepare a paste.

[0115] Next, the prepared paste was uniformly applied to the surface of the silicon carbide sintered body to a thickness of approximately 200 μm. After drying in a drying oven at a temperature of 100°C for 1 hour, the insulating coating material was melted by heating in an oxidation furnace, and the insulating coating was welded to the surface of the silicon carbide sintered body to obtain the heating elements of Example 1 and Comparative Example 1.

[0116] In Example 1, the insulating coating was welded to the material by heating it in an oxidation furnace at a temperature of 900°C for 30 minutes. In Comparative Example 1, the insulating coating was welded by heating in an oxidation furnace at a temperature of 980°C for 10 minutes.

[0117] Finally, the insulating coating surface was ground to achieve a parallelism of 3 μm or less for the heating element. The resulting insulating coating thickness was 50 μm. The parallelism of the insulating coating surface was calculated by measuring the thickness of nine points on the heating element using a dial gauge.

[0118] Elemental analysis of the insulating coatings in the heating elements of Example 1 and Comparative Example 1 was performed by ICP emission spectroscopy, and the composition of the insulating coatings was determined from the obtained results. Specifically, based on the content of each element obtained from the elemental analysis of the insulating coatings, the content of each oxide was calculated by assuming that all of the elements contained in the insulating coatings were oxides, and converting the measured values ​​from the elemental analysis.

[0119] In the elemental analysis performed in this embodiment, the detection limits for each element are as follows: B:20ppm, Al:5ppm, Zn:5ppm, Mg:5ppm, Ca:5ppm, Ba:10ppm, Na:200ppm

[0120] The results are shown in Table 1. In Table 1, the content of each oxide listed is shown with the total amount of each oxide set to 100% by mass.

[0121] [Table 1]

[0122] As shown in Table 1, the insulating film of Example 1 contained a total of 14.5% by mass of zinc oxide and magnesium oxide, while calcium oxide and barium oxide were below the detection limit. In the insulating film of Comparative Example 1, the content of the components added to the matrix was 5.0% by mass or less, and calcium oxide and barium oxide were detected.

[0123] Next, as shown in Figures 7 to 9, a silicon nitride sintered body serving as a heater base 21 was placed on the upper surface (back surface 1b) of the heating element. The heater base 21 is equipped with through holes 37 and 38 for cooling the heating element. Furthermore, M1.4 bolts were inserted through fastening through holes 13 and 14 to screw the heater base 21 to the heating element. In addition, an electrode 20 was formed by inserting an M1.4 countersunk screw through an electrode mounting hole 29 and fixing the end of a lead wire near the tip of the screw with a nut, thereby obtaining the SiC heaters of Example 1 and Comparative Example 1.

[0124] 〔evaluation〕 The SiC heaters obtained in Example 1 and Comparative Example 1 were subjected to heat cycle tests and insulation film resistance measurements using the following methods.

[0125] (Heat cycle test) A 10kg weight was placed over the entire surface where the insulating coating was formed on the SiC heater. The temperature was then raised from 50°C to 450°C in 1.5 seconds, and then cooled from 450°C to 50°C by blowing compressed air at an air pressure of 0.5MPa. This heating and cooling process constituted one heating and cooling cycle, and a heat cycle test was conducted by repeating this cycle multiple times. In the heat cycle test, each cycle was set to 20 seconds, and the cycle was repeated 10,000 times and 1,000,000 times.

[0126] Before the test, after 10,000 heating and cooling cycles, and after 1,000,000 heating and cooling cycles, the appearance of the insulating coating was observed, and the electrical resistance of the insulating coating was measured.

[0127] In the visual inspection, the focus was on whether or not cracks had formed in the insulating coating, and those without cracks were deemed acceptable.

[0128] The electrical resistance of the insulating coating was measured using an insulation resistance meter by applying a high voltage between the surface of the insulating coating and the heater electrode.

[0129] (Method for measuring electrical resistance) The electrical resistance of the insulating film at room temperature was measured using the SiC heaters of the examples and comparative examples, with an insulation resistance meter (HIOKI E.E. CORPORATION, 3453 DIGITAL MΩ HITESTER). Specifically, a titanium foil was placed on the surface of the insulating film, and a DC voltage of 500V was applied between the titanium foil and the SiC heater electrode 20 to measure the electrical resistance.

[0130] By placing a metallic titanium foil on an insulating coating and taking measurements, it is possible to confirm that all areas of the SiC heater surface are insulating.

[0131] The evaluation results are shown in Table 2.

[0132] [Table 2]

[0133] The evaluation results showed that the electrical resistance of the insulating coating measured immediately after fabrication was greater than 1000 MΩ for both the example and the comparative example, confirming that the SiC heater surface is insulating. Furthermore, the SiC heater of Example 1, which has the insulating coating of the present invention, did not develop any cracks even after 1 million heat cycle tests, and its electrical resistance exceeded the upper limit under the measurement conditions.

[0134] On the other hand, in Comparative Example 1, cracks were found in the insulating coating of the SiC heater after 10,000 heat cycle tests. It is believed that the insulating coating of the SiC heater in Comparative Example 1 was damaged due to expansion and contraction associated with heating and cooling under load. Since it was thought that repeated use of the SiC heater with the cracked insulating coating using the thermocompression bonding method would lead to further damage to the insulating coating, the test was terminated without measuring electrical resistance.

[0135] Based on the above results, it has been confirmed that the present invention is useful. [Explanation of symbols]

[0136] 1… Heating element 1A...Silicon carbide sintered body 1B...Insulating coating 2,3…Slits 4, 5… (Through holes for electrode mounting) 6…(For chip suction) Through hole 7, 8… (Through holes for heat transfer plate adsorption) 9, 10… (grooves for heat transfer plate adsorption) 11, 12… (Through holes for various gas supply) 13, 14… (Through holes for inserting mounting screws) 15... Countersunk screws 21… Heater base 21a... Counterbore section 22…Cooling system connection component 24... Lead wire (wiring) 26,27…Groove 28…Through hole 29… Electrode mounting holes 30… Heat transfer plate 31…(For chip suction) Through hole 32, 33… (Through holes for various gas supply) 35, 36… (Through holes for heat transfer plate adsorption on the groove side) 37, 38… (Through-holes for cooling gas supply) 40… Semiconductor chips 50... Circuit board 60... Conductive bonding material 100...SiC heater

Claims

1. A heating element having a thin, plate-shaped silicon carbide sintered body and an insulating coating formed on the surface of the silicon carbide sintered body, A pair of electrodes for supplying current to the heating element, The heater base includes a heater base that holds the heating element from one side while insulating it from the heat, The insulating coating is located on the side of the silicon carbide sintered body opposite to the heater base, The electrical resistance of the aforementioned insulating coating at room temperature is 10 ９ It is greater than or equal to Ω, The insulating coating is SiO ２ And, Al ２ O ３ and B ２ O ３ A matrix consisting of one or both of the following, The matrix includes, The aforementioned component is at least one selected from the group consisting of zinc oxide, gallium oxide, magnesium oxide, and tin oxide. A SiC heater in which the total content of the aforementioned components is greater than 5.0% by mass and less than or equal to 30.0% by mass of the entire insulating coating.

2. The SiC heater according to claim 1, comprising zinc oxide as the aforementioned component.

3. The SiC heater according to claim 1, comprising zinc oxide and magnesium oxide as the aforementioned components.

4. The SiC heater according to any one of claims 1 to 3, wherein the calcium content in the insulating film is less than or equal to the detection limit by ICP spectroscopy.

5. The SiC heater according to any one of claims 1 to 3, wherein the sodium content in the insulating film is less than or equal to the detection limit by ICP spectroscopy.

6. The SiC heater according to any one of claims 1 to 3, wherein the shape of the heating element is a substantially S-shape in plan view, having two slits cut from two opposing sides of a substantially square or substantially rectangular shape toward the opposite side, and both ends of the substantially S-shape are connected to one of the pair of electrodes.

7. The bonding density of the aforementioned silicon carbide sintered body is 2.5 g / cm³. ３ The SiC heater according to any one of claims 1 to 3, wherein the electrical resistivity at 25°C is 0.1 Ω·cm or more and 100 Ω·cm or less.

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