Heating disc for manufacturing photoetching mask

Abstract

The utility model discloses a heating disc for manufacturing a photoetching mask plate, which comprises a substrate, a bottom shell is detachably mounted at the bottom of the substrate, a heating wire is printed at the bottom of the substrate, and the heating wire is cured at the bottom of the substrate in a silk-screen printing and high-temperature baking manner. A groove body is formed in the side wall, facing the base plate, of the bottom shell, the heating wire is arranged in the groove body in the bottom shell, and a pair of temperature measuring thermal resistors is installed in a small hole formed in the center of the bottom of the base plate. According to the utility model, aluminum nitride is adopted as a base material of the mask plate heating plate, higher heating temperature can be tolerated, and the heating plate has better temperature uniformity and excellent plate surface temperature consistency at high temperature by utilizing the high heat conductivity coefficient of aluminum nitride ceramic and combining the heating wire printing layout calculated and optimized by simulation numerical values; through combined assembly, the mask heating plate is simple in structure, complete in function, suitable for modular installation, and efficient, simple and convenient to disassemble and maintain.

Description

Technical Field

[0001] The utility model belongs to the technical field of semiconductor component processing, and in particular relates to a heating plate for manufacturing a photolithography mask. Background Art

[0002] The mask, a master template used in the semiconductor lithography process, carries the designed microscopic circuit pattern and transfers it to semiconductor process materials such as silicon wafers through processes such as photolithography exposure and etching. The mask manufacturing process is similar to that of semiconductor wafer manufacturing and includes more than a dozen steps, including resist coating, pattern transfer, pattern photolithography, development, etching, stripping, optical inspection, and defect repair. During the resist coating stage, photoresist is applied to the mask substrate and the liquid photoresist is baked to a hard film before subsequent processing. There are two key technical aspects of mask baking: a high baking temperature, generally between 350 and 500°C. Another is the high temperature uniformity across the mask during baking. Only when the temperature is sufficiently uniform can the resulting hard film be uniform in thickness and free of localized pores.

[0003] The existing mask hotplate has the following aspects that need to be improved:

[0004] The current mask processing hot plates are mainly in the form of aluminum plates plus metal armored heating wires. Aluminum hot plates are limited by the melting point of aluminum itself and cannot meet the needs of high-temperature baking for masks. In addition to aluminum, there are also heating plates made of high-melting-point metal materials such as stainless steel and Hastelloy, which can be heated to the required high temperature. However, the thermal conductivity of metals such as stainless steel and Hastelloy is much lower than that of aluminum. The temperature uniformity of such high-temperature alloy hot plates is poor, which makes it difficult to meet the high temperature uniformity required for mask processing at high temperatures. Metal armored heating wires are used as the heat source of metal hot plates. Once the insulation inside the metal armored heating wire is not done well or the insulation fails during long-term use, the metal plate body will be connected to the heating wire, the plate body will be electrified or even spark, resulting in the product being unable to be processed or even damaging the machine.

[0005] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. Utility Model Content

[0006] The utility model aims to provide a heating plate for manufacturing photolithography masks, which can solve the problem that the existing heating plate cannot meet the requirements of manufacturing masks with different baking temperatures and has poor uniformity during baking.

[0007] In order to achieve the above-mentioned purpose, the technical solution provided by a specific embodiment of the present invention is as follows:

[0008] A heating plate for manufacturing photolithography masks comprises a substrate, the substrate being used to receive the mask so as to facilitate baking the mask. A bottom shell is detachably mounted on the bottom of the substrate, making it easy to disassemble and assemble the substrate and the bottom shell, and to facilitate disassembly and assembly between the substrate and the bottom shell, making it easy to maintain the components installed between the substrate and the bottom shell. A heating wire is printed on the bottom of the substrate, and the heating wire is solidified on the bottom of the substrate by screen printing and high-temperature baking. The heating wire is used to heat the substrate so as to facilitate baking the mask. A groove is provided on the side wall of the bottom shell facing the substrate, and the heating wire is placed in the groove on the bottom shell, so that when the bottom shell and the substrate are installed together, the heating wire on the bottom of the substrate can be placed in the groove on the bottom shell. A circular hole is opened at the center of the bottom shell, and a pair of temperature measuring resistors pass through the circular hole of the bottom shell. The lower ends of the pair of temperature measuring resistors are placed on the outside of the bottom shell, and the upper ends are inserted into the small hole in the middle of the bottom of the substrate and fixed. Through the pair of thermal resistors, the temperature generated by the heating wire can be fed back in real time, thereby facilitating the monitoring of the temperature during mask baking.

[0009] In one or more embodiments of the present invention, a plurality of first screw holes are evenly formed at the edge of the side wall of the base plate, and a plurality of second screw holes corresponding to the first screw holes are evenly formed at the edge of the side wall of the bottom shell.

[0010] In one or more embodiments of the present invention, a locking bolt is threadedly connected to the first and second screw holes. By installing the locking bolts in the first and second screw holes, the base plate and bottom shell are secured together, ensuring a stable connection between the base plate and bottom shell. A gasket is provided in the first screw hole, and the locking bolt is installed through the gasket, ensuring a stable fixation of the locking bolt to the base plate and bottom shell. The gasket is made of alumina ceramic to ensure stable performance in high-temperature environments.

[0011] In one or more embodiments of the present invention, the substrate is made of ceramic, and the ceramic is aluminum nitride ceramic. Using aluminum nitride ceramic as the base material for the mask heating plate allows the substrate to withstand higher heating temperatures. Furthermore, utilizing the high thermal conductivity of aluminum nitride ceramic, combined with a heating wire printing layout optimized through simulation numerical calculations, allows the heating plate to have better temperature uniformity, resulting in excellent temperature consistency across the surface of the substrate 2 at high temperatures.

[0012] In one or more embodiments of the present invention, a plurality of protrusions are provided on the upper surface of the substrate, and the height of the protrusions is set to 0.1 mm. The protrusions enable the mask to maintain a uniform distance from the upper surface of the substrate without completely fitting together, thereby improving the baking effect of the substrate on the mask, while improving the temperature uniformity transferred from the substrate to the mask, and preventing the photoresist on the mask from contaminating the substrate.

[0013] In one or more embodiments of the present invention, the surface of the substrate facing the bottom shell is polished, and the flatness of the surface of the substrate facing the bottom shell after polishing is less than 0.05 mm, so that the side of the substrate in contact with the heating wire has better flatness, so that the heating wire and the surface of the substrate can be completely fitted during the processing, so that the heat of the heating wire can be evenly transferred to the substrate, so that the substrate is heated evenly.

[0014] In one or more embodiments of the present invention, the bottom shell is made of stainless steel, preferably 310S stainless steel. The base plate and bottom shell are locked together using locking bolts and washers. This combination produces a simple, fully functional mask heating plate suitable for modular installation, and allows for efficient and easy disassembly and maintenance.

[0015] In one or more embodiments of the present invention, the mounting groove on the side of the bottom shell facing the base plate is opened by milling.

[0016] In one or more embodiments of the present invention, the heating filament is made of a metal paste composed of one or more of silver, silver palladium, and ruthenium platinum palladium. The heating filament is manufactured using a screen printing process, allowing the heating filament to be tailored to the number of heating filament turns, line width, and line spacing requirements. Furthermore, the heating filament can be cured at high temperatures on the bottom of the substrate, ensuring stability and performance after installation.

[0017] In one or more embodiments of the present invention, a power cord is mounted on the power supply end of the heating wire. The end of the power cord, which is distal to the heating wire, passes through a mounting hole in the bottom shell and is positioned outside the bottom shell. The power cord provides power to the heating wire, thereby generating heat. The power cord is made of pure nickel with a high-temperature-resistant mica sheath to protect it from high temperatures.

[0018] Compared with the prior art, the utility model has the following advantages:

[0019] 1. This mask high-temperature hot plate uses aluminum nitride as the plate base material, combined with the screen printing process, to print the metal paste onto the ceramic substrate, and then sinter the paste at high temperature to complete the metallization. The metallized heating wire serves as the heat source of the hot plate.

[0020] 2. Aluminum nitride is used as the base material of the mask heating plate, which can withstand higher heating temperatures. The high thermal conductivity of aluminum nitride ceramics is combined with the heating wire printing layout optimized by simulation numerical calculations to ensure better temperature uniformity of the heating plate and excellent temperature consistency of the plate surface at high temperatures.

[0021] 3. A stainless steel bottom shell is used, which is locked with locking bolts and alumina ceramic gaskets. Holes are processed on the back of the aluminum nitride substrate, and the thermal resistor and power cord are connected by crimping. The mask heating plate processed by this combination has a simple structure and complete functions, is suitable for modular installation, and is efficient and easy to disassemble and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 A three-dimensional heating plate for manufacturing a photolithography mask in an embodiment of the present invention Figure 1 ;

[0024] Figure 2 A three-dimensional heating plate for manufacturing a photolithography mask in an embodiment of the present invention Figure 2 ;

[0025] Figure 3 This is an exploded view of a heating plate for manufacturing a photolithography mask in one embodiment of the present invention.

[0026] Description of main reference numerals:

[0027] 1-gasket, 2-base plate, 3-heating wire, 4-bottom shell, 5-temperature measuring resistor, 6-power cord. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the following will be combined with the drawings of the embodiments of the present invention to clearly and completely describe the technical solutions of the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0029] like Figures 1 to 3As shown, a heating plate for manufacturing a photolithography mask in one embodiment of the present invention is used to solve the problem that the existing heating plate cannot meet the requirements of manufacturing masks with different baking temperatures and has poor uniformity during baking.

[0030] like Figures 1 to 3 As shown, a heating plate for manufacturing a photolithography mask includes a substrate 2, which is used to receive the mask so that the mask can be baked. A bottom shell 4 is installed on the bottom of the substrate 2 in a detachable manner, so that the substrate 2 and the bottom shell 4 are easy to disassemble and assemble, and the components installed between the substrate 2 and the bottom shell 4 are easy to disassemble and assemble. The bottom of the substrate 2 is printed with a heating wire 3, and the heating wire is solidified on the bottom of the substrate 2 by screen printing and high-temperature baking. The heating wire 3 is used to heat the substrate 2 so that the substrate 2 can bake the mask. A groove is opened on the side wall of the bottom shell 4 facing the substrate 2, and the heating wire 3 is placed in the groove on the bottom shell 4, so that when the bottom shell 4 and the substrate 2 are installed together, the heating wire 3 at the bottom of the substrate 2 can be placed in the groove on the bottom shell 4. A circular hole is opened at the center of the bottom shell 4, and a pair of temperature measuring thermal resistors 5 pass through the circular hole of the bottom shell 4. The lower ends of the pair of temperature measuring thermal resistors 5 are placed on the outside of the bottom shell 4, and the upper ends are inserted into the small hole in the middle of the bottom of the substrate 2 and fixed. Through the pair of thermal resistors 5, the temperature generated by the heating wire 3 can be fed back in real time, thereby facilitating the monitoring of the temperature during the baking of the mask.

[0031] like Figure 1 and Figure 3 As shown, a plurality of first screw holes are evenly formed at the edge of the side wall of the base plate 2 , and a plurality of second screw holes corresponding to the first screw holes are evenly formed at the edge of the side wall of the bottom shell 4 .

[0032] like Figures 1 to 3 As shown, locking bolts are threadedly connected to the first and second screw holes. By installing the locking bolts in the first and second screw holes, the base plate 2 and bottom case 4 are fixed together, ensuring a stable connection between the base plate 2 and bottom case 4. A gasket 1 is provided in the first screw hole, and the locking bolt is installed in a penetrating manner within the gasket 1, which ensures a stable fixation of the locking bolt to the base plate 2 and bottom case 4. The gasket 1 is also made of alumina ceramic to ensure stable performance in high-temperature environments.

[0033] Preferably, the substrate 2 is made of ceramic, preferably aluminum nitride. Using aluminum nitride as the base material for the mask heating plate allows the substrate 2 to withstand higher heating temperatures. Furthermore, utilizing the high thermal conductivity of aluminum nitride, combined with a heating wire printing layout optimized by simulation numerical calculations, allows the heating plate to have better temperature uniformity, resulting in excellent temperature consistency across the surface of the substrate 2 at high temperatures.

[0034] Furthermore, a plurality of protrusions are provided on the upper surface of the substrate 2, and the height of the protrusions is set to 0.1 mm. The protrusions enable the mask to maintain a uniform distance from the upper surface of the substrate 2 without completely fitting together, thereby improving the baking effect of the substrate 2 on the mask, while improving the temperature uniformity transferred from the substrate 2 to the mask, and avoiding the photoresist on the mask from contaminating the substrate.

[0035] Furthermore, the surface of the substrate 2 facing the bottom shell 4 is polished, and the flatness of the surface of the substrate 2 facing the bottom shell 4 after polishing is less than 0.05 mm, so that the flatness of the side of the substrate 2 in contact with the heating wire 3 is better, so that the heating wire 3 and the surface of the substrate 2 can be completely fitted, so that the heat of the heating wire 3 can be evenly transferred to the substrate 2, so that the substrate 2 is heated evenly.

[0036] Preferably, the bottom shell 4 is made of stainless steel, and the stainless steel material is selected to be 310S stainless steel. The base plate 2 and the bottom shell 4 are locked using a locking bolt and a gasket 1. The mask heating plate processed in this combination has a simple structure and complete functions, is suitable for modular installation, and is efficient and easy to disassemble and maintain.

[0037] Preferably, the mounting groove on the side of the bottom shell 4 facing the base plate 2 is opened by milling.

[0038] Preferably, the heating wire 3 is arranged at the bottom of the substrate 2 through a screen printing process, and the material of the heating wire 3 is a metal paste composed of one or more of silver, silver palladium and ruthenium platinum palladium. The production of the heating wire 3 through the screen printing process allows the heating wire 3 to be cured at a high temperature at the bottom of the substrate 2, so that the substrate 2 and the heating wire 3 are in close contact, thereby improving the efficiency and uniformity of the heat transfer from the heating wire 3 to the substrate 2. With the help of numerical simulation tools, the circuit layout of the heating wire 3 at the bottom of the substrate 2 is gradually optimized, and then the appropriate number of heating wire turns, line width, line spacing, etc. are determined, the circuit layout is produced, and the corresponding screen printing jig is processed.

[0039] like Figures 1 to 3 As shown, a power cord 6 is installed at the power supply end of the heating wire 3. The end of the power cord 6 away from the heating wire 3 passes through the mounting hole on the bottom shell 4 and is placed on the outside of the bottom shell 4. Power is provided to the heating wire 3 through the power cord 6, so that the heating wire 3 generates heat. At the same time, the power cord 6 is made of a high-temperature resistant mica-sheathed pure nickel power cord so that it will not be affected by high temperatures.

[0040] When in use, the substrate 2 serves as the main body of the hot plate, and the front side is used to carry the processed mask plate. A resistor paste containing silver, silver palladium or ruthenium platinum palladium is printed on the back side of the substrate 2 using a screen printing process, and sintered in an atmospheric atmosphere at medium to high temperature to complete the metallization of the resistor paste and the sintering adhesion to the ceramic substrate. The metallized resistor circuit serves as the heat source of the hot plate, so that the heating wire 3 can be installed on the bottom of the substrate 2 by attachment; the bottom of the substrate 2 is the bottom shell 4, and the substrate 2 is suspended by the bottom shell 4 to protect the circuit of the heating wire 3; the substrate 2 and the bottom shell 4 are locked using a gasket 1 and a locking bolt; a pair of temperature measuring resistors 5 and a power cord 6 are connected through the mounting holes on the bottom shell 4 and in the form of crimping; the temperature measuring resistors 5 are used to monitor the temperature of the hot plate and perform temperature control and adjustment, and the power cord 6 is used to supply power to the heating wire 3.

[0041] This application innovatively combines screen printing technology, resistor paste metallization and high thermal conductivity with substrate 2 to design a mask heating aluminum nitride high-temperature ceramic heating plate that can provide a high temperature of 500°C and has excellent temperature uniformity. Through combined assembly, the mask heating plate has a simple structure and complete functions, is suitable for modular installation, and is efficient and easy to disassemble and maintain.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0043] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A heating plate for manufacturing a photolithography mask, comprising a substrate, characterized in that: The bottom of the substrate is detachably mounted with a bottom shell, the bottom of the substrate is printed with a heating wire, and the heating wire is solidified on the bottom of the substrate by screen printing and high-temperature baking. A groove is provided on a side wall of the bottom shell facing the substrate, and the heating wire is placed in the groove on the bottom shell. A circular hole is provided at the center of the bottom shell, and a pair of temperature measuring resistors are installed in a small hole in the center of the bottom of the substrate. The pair of temperature measuring resistors pass through the central circular hole of the bottom shell when installed.

2. A heating plate for manufacturing a photolithography mask according to claim 1, characterized in that: A plurality of first screw holes are evenly formed on the side wall edge of the base plate, and a plurality of second screw holes corresponding to the first screw holes are evenly formed on the side wall edge of the bottom shell.

3. The heating plate for manufacturing a photolithography mask according to claim 2, characterized in that: The first screw hole and the second screw hole are threadedly connected with a locking bolt, a gasket is provided on the first screw hole, and the locking bolt is installed in the gasket in a penetrating manner.

4. The heating plate for manufacturing a photolithography mask according to claim 1, characterized in that: The substrate is made of ceramic, and the ceramic is aluminum nitride ceramic.

5. The heating plate for manufacturing a photolithography mask according to claim 4, characterized in that: A protrusion is provided on the upper surface of the substrate, and the height of the protrusion is set to 0.1 mm.

6. The heating plate for manufacturing a photolithography mask according to claim 5, characterized in that: The surface of the substrate facing the bottom shell is polished, and the flatness of the polished surface of the substrate facing the bottom shell is less than 0.05 mm.

7. The heating plate for manufacturing a photolithography mask according to claim 1, characterized in that: The bottom shell is made of stainless steel, and the stainless steel material is 310S stainless steel.

8. The heating plate for manufacturing a photolithography mask according to claim 7, characterized in that: The mounting groove on the side of the bottom shell facing the base plate is opened by milling.

9. The heating plate for manufacturing a photolithography mask according to claim 1, characterized in that: The material of the heating wire is a metal slurry composed of one or more of silver, silver palladium and ruthenium platinum palladium.

10. The heating plate for manufacturing a photolithography mask according to claim 9, characterized in that: A power line is installed at the power supply end of the heating wire, and one end of the power line away from the heating wire passes through the installation hole on the bottom shell and is placed on the outside of the bottom shell.

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