JP5422413B2 - Heat dissipation member and manufacturing method thereof - Google Patents

Description

The present invention relates to a member with reduced contact thermal resistance. In particular, the present invention relates to a heat radiating member such as a semiconductor wafer, a member that requires heat exchange, such as a focus ring and a heat sink.

A plasma etching apparatus is known as an apparatus for etching a silicon wafer when manufacturing a semiconductor integrated circuit. As described in Patent Document 1, a focus ring and a mounting table on which the focus ring is installed are described. In order to improve the heat conduction, a method for improving the heat conduction by interposing a heat conduction sheet therebetween has been studied.
In the structure of the focus ring and the heat conductive sheet described above, there is not less than each between the focus ring and the heat conductive sheet, and between the heat conductive sheet and the mounting table, and there is an air layer as a heat insulating layer, and the interface resistance is not necessarily reduced. There is no. For this reason, the focus ring during the plasma etching process does not necessarily radiate heat appropriately, and the focus ring itself is likely to deteriorate.
Also, when attaching a normal heat dissipation sheet, cut according to the ring shape, and then affix the heat dissipation sheet, but it takes time and effort, and it is not easy to bond together, so workability is poor and a heat insulation layer is likely to occur. There was a possibility that the heat dissipation characteristics would deteriorate.
Thus, although a method of pressing and fixing to the mounting table of Patent Document 1 has been proposed, it is difficult to manufacture a focus ring excellent in heat dissipation characteristics by accurately attaching a heat dissipation sheet to any desired place.

JP 2008-244096 Gazette

An object of the present invention is to provide a heat dissipating member having excellent heat dissipating properties by printing, applying and curing a resin composition having excellent heat conductivity on the member, and to provide a manufacturing method thereof.

The present invention employs the following means in order to solve the above problems.
(1) A resin composition containing 40-60% by volume of polyorganosiloxane and 25-60% by volume of an inorganic filler having a maximum particle size of 80 μm or less and having a viscosity of 500-50000 mPa · s is applied by printing on a focus ring. A focus ring , wherein the resin composition is cured on the member.
(2) The focus ring according to (1) above, wherein the polyorganosiloxane has an average molecular weight of 10,000 to 50,000.
(3) The inorganic filler is selected from the group consisting of alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, silver, copper, aluminum, carbon, diamond, zinc oxide, magnesia, aluminum hydroxide and magnesium hydroxide. The focus ring according to (1) or (2), wherein the focus ring includes one or more types.
(4) The average particle diameter of the inorganic filler is 1.5 μm or more and less than 4.5 μm, and the maximum particle diameter is 20 μm or less, according to any one of (1) to (3), Focus ring .
(5) The particle size distribution of the inorganic filler has at least two maximum values in the particle size ranges of 4.5 μm or more and less than 6.5 μm, 1.5 μm or more and less than 4.5 μm, and 0.3 μm or more and less than 0.8 μm. The focus ring according to any one of (1) to (4), wherein
( 6 ) A resin composition containing 40-60% by volume of polyorganosiloxane and 25-60% by volume of an inorganic filler having a maximum particle size of 80 μm or less and having a viscosity of 500-50000 mPa · s is printed on the focus ring. A method for producing a heat radiating member, wherein the resin composition is cured on the focus ring .
( 7 ) The method for producing a heat dissipation member as described in ( 6 ) above, wherein the polyorganosiloxane has an average molecular weight of 10,000 to 50,000.
( 8 ) The inorganic filler is selected from the group consisting of alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, silver, copper, aluminum, carbon, diamond, zinc oxide, magnesia, aluminum hydroxide and magnesium hydroxide. One or more types are included, The manufacturing method of the heat radiating member as described in said ( 6 ) or ( 7 ) characterized by the above-mentioned.
( 9 ) The average particle size of the inorganic filler is not less than 1.5 μm and less than 4.5 μm, and the maximum particle size is not more than 20 μm, and any one of ( 6 ) to ( 8 ) above Manufacturing method of heat dissipation member.
( 10 ) The particle size distribution of the inorganic filler has at least two maximum values in the particle size ranges of 4.5 μm or more and less than 6.5 μm, 1.5 μm or more and less than 4.5 μm, and 0.3 μm or more and less than 0.8 μm. The method for manufacturing a heat radiating member according to any one of ( 6 ) to ( 9 ), which is characterized in that
( 11 ) The method for manufacturing a heat radiating member according to any one of ( 6 ) to ( 10 ), wherein the thickness of printing and applying the resin composition to the focus ring is 5 to 100 μm.
( 12 ) The method for producing a heat radiating member according to any one of ( 6 ) to ( 11 ), wherein the resin composition is printed on a focus ring by a screen printing method.
(13) the surface roughness of the focus ring is said to characterized by print coating a resin composition to 0.05μm or more 10μm or less of the focus ring surface with the value of Ra of JIS B 0601 (6) to (12) The manufacturing method of the heat radiating member of any one of Claims 1.

By using the heat dissipation member of the present invention, the contact thermal resistance with other members can be significantly reduced.
Moreover, the heat radiating member which coat | covered the surface of the member with the resin composition excellent in heat conductivity by this invention can be manufactured efficiently. The present invention is particularly suitable for a focus ring.

Schematic which shows an example of a focus ring and a resin composition. Schematic which shows an example of a focus ring and a resin composition (enlarged view which divided | segmented FIG. 1).

The present invention provides a heat dissipating member having excellent heat dissipating properties by printing, applying and curing a resin composition having excellent heat conductivity on the member. The present invention uses a printing method as a method for applying a resin composition having excellent thermal conductivity to a member, thereby not only significantly reducing contact thermal resistance with other members but also making the surface of the member thermally conductive. The heat radiating member coated with the excellent resin composition can be efficiently produced.

The member of the present invention is a member that requires heat dissipation, and examples thereof include a semiconductor member, a heat sink, a heat spreader, a light emitting member, and a focus ring. Of these, the member is preferably a focus ring.

The polyorganosiloxane of the present invention is preferably thermosetting among the polyorganosiloxanes, and it is preferable to use a curing agent (crosslinkable polyorganosiloxane) in addition to the main polyorganosiloxane polymer. Examples of the repeating unit structure of the polyorganosiloxane include a dimethylsiloxane unit, a phenylmethylsiloxane unit, and a diphenylsiloxane unit. Moreover, you may use the modified polyorganosiloxane which has functional groups, such as a vinyl group and an epoxy group.
The polyorganosiloxane of the present invention preferably has an average molecular weight of 10,000 to 50,000. When the average molecular weight is 10,000 or less, the polyorganosiloxane and the filler tend to be easily separated. On the other hand, when the average molecular weight exceeds 50000, the coating thickness of the resin composition is increased, so that heat radiation is insufficient and the temperatures of the focus ring surface and the resin composition surface may be increased.

The inorganic filler of the present invention is alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, silver, copper, aluminum, carbon, diamond, zinc oxide, magnesia, aluminum hydroxide and magnesium hydroxide. The inorganic filler preferably has a spherical structure, and those having anisotropy in shape as heat transfer characteristics are preferably oriented so as to maximize the heat transfer characteristics. Among these, preferred inorganic fillers are alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, silver, copper, aluminum, carbon, diamond, and zinc oxide.

The maximum particle size of the inorganic filler is 80 μm or less, and preferably 20 μm or less. When the maximum particle size exceeds 80 μm, the inorganic filler particles may become protrusions on the coated surface when the resin composition is coated, which is not preferable because the smoothness of the coated surface may be impaired. If the smoothness of the coated surface is impaired, the heat path is deteriorated and the thermal conductivity is deteriorated.

The average particle size of the inorganic filler is preferably 1.5 μm or more and less than 4.5 μm.

The particle size distribution of the inorganic filler preferably has at least two maximum values in the particle size ranges of 4.5 μm to less than 6.5 μm, 1.5 μm to less than 4.5 μm, and 0.3 μm to less than 0.8 μm.

The blend of the polyorganosiloxane and the inorganic filler is 40 to 75% by volume of the polyorganosiloxane and 25 to 60% by volume of the inorganic filler. When the inorganic filler is 25% by volume or less, the heat dissipation property is deteriorated because the thermal conductivity is small. For this reason, the resin composition itself on the surface of the member is heated, which causes the resin composition to deteriorate. Moreover, when the inorganic filler is 75% by volume or more, the inorganic filler is not sufficiently dispersed in the polyorganosiloxane, and screen printing becomes difficult.

The resin composition of the present invention can be produced by kneading the above materials with a universal mixing stirrer, kneader, hybrid mixer or the like.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an example of a focus ring as an example of a heat dissipation member whose surface is modified with a cured product of the resin composition of the present invention. FIG. 2 shows an example of divided pieces of the focus ring. When the focus ring is installed in the plasma etching apparatus, it is composed of a cured product 2 of the resin composition disposed on the surface 1 of the focus ring that comes into contact with the mounting table.

By coating or applying a resin composition with excellent thermal conductivity on the surface of a member, the contact thermal resistance when the member comes into contact with another member can be reduced, and the heat dissipation characteristics from the member can be improved. Can do. Here, the surface of the focus ring refers to a surface that comes into contact with the mounting table when the focus ring is installed in, for example, a plasma etching apparatus, and the contact thermal resistance generally contacts two different substances. When arranged in such a manner, an air layer exists microscopically at the boundary between two different substances. This air layer becomes a resistance during heat transfer and deteriorates heat conduction. The influence of the heat conduction deterioration by this space | gap is said.

In the manufacturing method of the focus ring, a resin composition having excellent thermal conductivity is coated or applied to the surface of the focus ring or an equivalent member having a different shape. As the coating or coating method, it is preferable to print and apply the resin composition on the member surface by screen printing. By performing screen printing, it is possible to accurately apply various shapes to the surfaces of the focus ring and similar members.

In the screen plate making, the shape is limited as a printing range by coating a photosensitive resin (emulsion) on the screen plate by a direct method, and applying and exposing a positive film having a printing shape. In addition, an indirect method may be used in which a film in which a photosensitive resin emulsion film is formed on a support film having excellent flatness is attached to a plate and the film is formed by peeling the support film, and is not particularly limited.
Furthermore, application by the screen printing method is excellent in that any shape can be printed freely and accurately, and the printing application area can be limited to the application area and non-application area by the patterning design of the screen plate. This is useful in that it can be applied even in any shape. The application shape is more flexible than a bar coater that uniformly applies the surface shape from end to end, and the non-application area is more efficient in terms of workability than the encoater application that requires a sealing treatment.

The material of the screen plate, the wire diameter, and the aperture are not particularly limited, but generally nylon, polyester, stainless steel, the wire diameter is 18 to 250 μm, and the aperture is generally in the range of 30 to 500 mesh. The

The screen printing machine is not particularly limited as long as it is a screen printing apparatus that can smoothly perform the printing operation and the screen mesh peeling operation, and a flat screen printing machine is generally used. For the screen printing alignment, a dedicated alignment jig may be installed in the printing press, or may be installed using an alignment camera.

The resin composition has a viscosity of 500 to 50000 mPa · s, preferably 1000 to 10000 mPa · s, measured according to JIS Z 8803 with a rotational viscometer RVDV1 manufactured by Brookfield. When the viscosity is less than 500 mPa · s, bleeding tends to occur on the resin surface when the resin composition is formed into a sheet, and it is difficult to maintain the shape. In addition, when the viscosity exceeds 50000 mPa · s, when the resin composition is formed into a sheet shape, the uneven shape of the mesh and air bubbles remain on the resin surface, and flattening becomes difficult. Therefore, when screen printing is performed, it is necessary to limit the viscosity range of the resin composition in order to achieve suitable shape retention and surface flattening.

The resin composition applied using the screen printing method was heated at 150 ° C. and cured to form a highly thermally conductive resin composition layer on the focus ring.

The thickness of the cured resin composition is preferably 5 to 100 μm, more preferably 30 to 100 μm, from the viewpoint of improving adhesion and heat dissipation characteristics.

The surface roughness of the focus ring is a value of Ra according to JIS B 0601, and is preferably 0.05 μm or more and 10 μm or less.
When the surface roughness is 10 μm or more, the coated surface of the resin after curing is not smooth because the surface is rough, the adhesion is inferior, the resin composition is broken at the time of adhesion, and the heat radiation is inferior because of poor adhesion. It may cause problems such as worsening, which is not preferable.
A focus ring or an equivalent member surface having a different shape is coated or coated with a resin composition by a screen printing method to modify the surface.

Examples 1-16, Comparative Examples 1-5
The resin compositions having the formulations shown in Tables 1 to 4 were kneaded for 120 seconds in total with a hybrid mixer (AR-250 manufactured by Sinky). After kneading, the resin composition was applied to the surface of the focus ring by screen printing and cured. After curing, the heat dissipation characteristics of the focus ring were evaluated. In addition, as a comparative example, the resin composition of the present invention was formed into a sheet and placed on the upper surface of the focus ring. The results are shown in Tables 1-4. The sheet sample used for the measurement was applied to a predetermined thickness on a release film using a bar coater and cured to prepare a sheet.
In addition, as Comparative Example 6, in the case of only the focus ring without using the heat dissipation member, the temperature of the focus ring surface was 200 ° C.

(1) Sample preparation method The focus ring member was placed on a surface plate of a screen printing machine (LT56-TVA manufactured by Neurong Seimitsu Kogyo Co., Ltd.), and alignment was performed using a three-point camera. For the screen plate, the wire diameter, thickness, and permeation volume are selected, and the resin composition is put on the plate using a screen plate in which the coating surface is limited by an emulsion so as to have a desired shape. The resin composition was applied to the surface on the focus ring. The application shape is a circular shape in which three non-application portions are installed. The non-application portion is a positioning alignment hole of the focus ring.
Thereafter, the focus ring member was heated and cured at 150 ° C. for 15 minutes to obtain a sample of the present invention. After that, various physical properties of the focus ring were evaluated.
The material of the focus ring is Si, the shape is a ring shape, the outer diameter is 360 mm, the inner diameter is 324 mm, and the thickness is 3.4 mm.
(2) The viscosity viscosity was measured based on JIS Z 8803 for the resin composition immediately before screen printing with a rotational viscometer RVDV1 manufactured by Brookfield. Using the RV spindle set, the rotor No. 7 is used, and the container in which the rotor enters and can enter to the reference line is used. The rotor was immersed in the resin composition, and the viscosity value at a rotation speed of 20 rpm was measured.
(3) Application thickness Measurement of the application thickness was performed using a laser displacement meter LT-9010M manufactured by Keyence Corporation. Focus the resin composition coated focus ring on the surface of the laser displacement meter placed on the surface plate and match the vicinity of the resin composition coating surface as a reference point (zero), and measure the thickness of the resin composition applied to the reference point. .
(4) Evaluation temperature Evaluation temperature is a thermocouple for temperature measurement (Teflon-coated thermocouple manufactured by Ninomiya Electric Co., Ltd .: wire diameter 0.1 μm and Keyence data logger NR-600) on the focus ring surface and the resin composition surface. This temperature was measured.
(5) Thermal conductivity after curing of resin composition As a method for measuring thermoelectric conductivity, a sample (1 mm thickness) obtained by applying the resin composition to a peeled PET film by bar coating was cured in an oven at 150 ° C for 15 minutes. A rectangular parallelepiped copper jig (tip area is 1 cm ² (1 cm × 1 cm)) embedded with a heater and a rectangular parallelepiped copper jig (tip area is 1 cm) to which cooling fins are attached. ² (1 cm × 1 cm)). Place a load of 10 psi on the adhered sample, apply 20 W to the heater and hold for 30 minutes, measure the temperature difference (° C.) between the copper jigs,
Formula, thermal conductivity (W / mK) = thickness (m) / (cross-sectional area (m ² ) × thermal resistance (° C./W))
Thermal resistance (° C./W)=(heater side temperature (° C.) − Cooling side temperature (° C.)) / Power (W).
(5) Surface roughness The surface roughness of the focus ring is measured by continuously scanning the surface of the focus ring member with a three-dimensional laser microscope (Keyence VK-9700) according to JIS B 0652. It described according to Ra of B 0601.

The materials used are shown below.
Polyorganosiloxane (1) XE14-B8530 (agent A): Momentive Performance Materials LLC XE14-B8530 (agent B): Momentive Performance Materials LLC (2) XE14-B1057 (agent A): Momentive Performance Materials Joint Company XE14-B1057 (agent B): Momentive Performance Materials LLC (3) TSE3450 (agent A): Momentive Performance Materials LLC TSE3450 (agent B): Momentive Performance Materials LLC (4) Silgel 613 (agent A) ): Asahi Kasei Wacker Silicone Co., Ltd. Silgel 613 (B agent): Asahi Kasei Wacker Silicone Co., Ltd. polyorganosiloxane (curing agent)
(5) RD-1: Toray Dow Corning Silicone Alumina (6) DAM70: Electrochemical Industry (7) DAM45: Electrochemical Industry (8) DAM5: Electrochemical Industry (9) Al (# 600): Minalco (10) AX3: Micron aluminum nitride (11) AlN (H grade): Tokuyama zinc oxide (12) ZnO (one type): Sakai Chemical

The average molecular weight of the polyorganosiloxane was a value in terms of polystyrene determined from the results of gel permeation chromatography analysis. The separation was a non-aqueous porous gel (polystyrene-dimethylbenzene copolymer), toluene was used as the mobile phase, and a differential refractometer (RI) was used for detection.
The average particle diameter, the maximum particle diameter, and the maximum value of the inorganic filler were measured using “Laser Diffraction Particle Size Distribution Analyzer SALD-20” manufactured by Shimadzu Corporation. As an evaluation sample, 5 g of 50 cc of pure water and an inorganic filler powder to be measured were added to a glass beaker, stirred using a spatula, and then subjected to dispersion treatment for 10 minutes with an ultrasonic cleaner. The solution of the inorganic filler powder that had been subjected to the dispersion treatment was added drop by drop to the sampler portion of the apparatus using a dropper, and waited until the absorbance became measurable. The measurement is performed when the absorbance becomes stable in this way. In the laser diffraction type particle size distribution measuring device, the particle size distribution is calculated from the data of the light intensity distribution of the diffracted / scattered light by the particles detected by the sensor. The average particle size is obtained by multiplying the value of the measured particle size by the relative particle amount (difference%) and dividing by the total relative particle amount (100%). The average particle diameter is the average diameter of the particles.

As is clear from the comparison between the example and the comparative example, the focus ring constructed according to the present invention has a lower surface temperature and superior heat dissipation characteristics than those formed into a sheet and installed on the upper surface of the focus ring. It was. The focus ring coated with the resin composition of the present invention means that the contact thermal resistance is reduced as compared with the conventional focus ring and the focus ring in which the heat dissipation sheet is installed on the upper surface. It was possible to provide an excellent member.

The shape application results on the member surface are shown in Tables 1-4. In the screen printing method, a resin composition could be applied to a member having three non-application portions in a ring shape at an arbitrary thickness and location.
On the other hand, the encoder is a method in which the resin composition is dropped while directly rotating the focus ring member with the encoder, and the resin is applied to the non-application region where the ring-shaped three non-application portions are formed. The composition was applied, and the resin composition could not be applied to any part of the member.
In addition, the evaluation of the shape application was evaluated as “◯” when the resin composition could be applied at an arbitrary thickness and location, and “X” when the resin composition could not be applied.

(Figure 1)
1 Focus ring 2 Cured resin composition

(Figure 2)
1 Focus ring 2 Cured resin composition

Claims (13)

A resin composition containing 40-60% by volume of polyorganosiloxane and 25-60% by volume of an inorganic filler having a maximum particle size of 80 μm or less and having a viscosity of 500-50000 mPa · s is printed on the member, and the resin composition A focus ring in which an object is cured on the member. 2. The focus ring according to claim 1, wherein the polyorganosiloxane has an average molecular weight of 10,000 to 50,000. One or more inorganic fillers selected from the group consisting of alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, silver, copper, aluminum, carbon, diamond, zinc oxide, magnesia, aluminum hydroxide and magnesium hydroxide The focus ring according to claim 1, comprising: 4. The focus ring according to claim 1, wherein the inorganic filler has an average particle size of 1.5 μm or more and less than 4.5 μm and a maximum particle size of 20 μm or less. The particle size distribution of the inorganic filler has at least two maximum values in particle size ranges of 4.5 μm or more and less than 6.5 μm, 1.5 μm or more and less than 4.5 μm, and 0.3 μm or more and less than 0.8 μm. The focus ring according to any one of claims 1 to 4. A resin composition containing 40 to 75% by volume of polyorganosiloxane and 25 to 60% by volume of an inorganic filler having a maximum particle size of 80 μm or less and having a viscosity of 500 to 50000 mPa · s is applied by printing on a focus ring. A method for producing a heat dissipation member, wherein the composition is cured on the focus ring . The average molecular weight of polyorganosiloxane is 10,000 or more and 50000 or less, The manufacturing method of the heat radiating member of Claim 6 characterized by the above-mentioned. One or more inorganic fillers selected from the group consisting of alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, silver, copper, aluminum, carbon, diamond, zinc oxide, magnesia, aluminum hydroxide and magnesium hydroxide The manufacturing method of the heat radiating member of Claim 6 or 7 characterized by the above-mentioned. The method for producing a heat radiating member according to any one of claims 6 to 8 , wherein the inorganic filler has an average particle size of 1.5 µm or more and less than 4.5 µm and a maximum particle size of 20 µm or less. . The particle size distribution of the inorganic filler has at least two maximum values in particle size ranges of 4.5 μm or more and less than 6.5 μm, 1.5 μm or more and less than 4.5 μm, and 0.3 μm or more and less than 0.8 μm. The manufacturing method of the heat radiating member of any one of Claims 6 thru | or 9 . The method for manufacturing a heat radiating member according to any one of claims 6 to 10 , wherein the thickness of the resin composition printed on the focus ring is 5 to 100 µm. The method for producing a heat radiating member according to any one of claims 6 to 11 , wherein the resin composition is printed on the focus ring by a screen printing method. Radiator according to any one of claims 6 to 12, characterized in that the surface roughness Print JISB 0601 Ra values resin composition 10μm or less of the focus ring surface than 0.05μm in at application of the focus ring Manufacturing method of member.

Images