Novel inverted heating device

Abstract

The utility model discloses a novel inverted heating device, which comprises a heating chamber, a heating module, two groups of XYZ modules I and a wafer tray are arranged in the heating chamber, the heating module comprises a heating plate arranged at the top in the heating chamber, the heating plate is provided with a plurality of vacuum holes, the plurality of vacuum holes are communicated with an external vacuum pump, and the wafer tray is arranged in the heating chamber. The two groups of XYZ modules I are connected with clamping arms, and the two groups of XYZ modules can clamp, lift and convey a wafer tray through the clamping arms; the cooling chamber is communicated with the heating chamber, a cold plate and two groups of XYZ modules II are arranged in the cooling chamber, a cooling pipeline is arranged on the back surface of the cold plate, and the two groups of XYZ modules II can be matched with the two groups of XYZ modules I to realize transportation of the wafer tray between the two chambers and lifting of the wafer tray in the cooling chamber; the novel inverted heating device integrates the functions of high-precision temperature control, vacuum adsorption, inert gas protection and rapid cooling, so that the uniformity, efficiency and yield of photoresist treatment are improved.

Description

Technical Field

[0001] This utility model relates to the field of heating device technology, and more specifically to a novel inverted heating device. Background Technology

[0002] In the semiconductor manufacturing and microelectronics processing fields, the heating and cooling processes in photolithography are crucial for the uniformity, curing effect, and defect control of photoresist. Traditional heating devices (such as ovens) typically use radiation or thermal convection to heat wafers, but these methods have the following significant drawbacks:

[0003] Insufficient heating uniformity: The uneven heat distribution in traditional ovens leads to uneven heating of wafers. This is especially true for wafers with large areas or high precision requirements, which can easily cause local temperature differences, resulting in inconsistent photoresist curing and affecting the accuracy of pattern transfer.

[0004] Bubble defect problem: During the high-temperature baking process, the solvent inside the photoresist evaporates and easily forms bubbles. Especially in the presence of oxygen, the bubble defect is more obvious, leading to a decrease in product yield.

[0005] Low cooling efficiency: Traditional cooling methods rely on natural cooling or simple air cooling, which takes a long time (usually several minutes), prolonging the production cycle. Insufficient cooling rate may cause secondary flow of photoresist, damaging the formed microstructure.

[0006] Limited temperature control accuracy: The temperature control accuracy of existing heating devices is generally above ±2℃, which is difficult to meet the stringent requirements of high-precision photolithography processes (such as extreme ultraviolet lithography) for temperature fluctuations (within ±0.1℃). Utility Model Content

[0007] To address the shortcomings of existing technologies, this invention provides a novel inverted heating device that integrates high-precision temperature control, vacuum adsorption, inert gas protection, and rapid cooling functions to improve the uniformity, efficiency, and yield of photoresist processing.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A novel inverted heating device includes:

[0010] The heating chamber contains a heating module, two sets of XYZ modules, and a wafer tray. The heating module includes a heating plate located at the top of the heating chamber and has several vacuum holes that are connected to an external vacuum pump. Each of the two sets of XYZ modules is connected to a clamping arm, which allows the two sets of XYZ modules to clamp, lift, and transport the wafer tray.

[0011] The cooling chamber is located on one side of the heating chamber and communicates with the heating chamber. A door is provided between the cooling chamber and the heating chamber. The cooling chamber is equipped with a cold plate and two sets of XYZ modules. The cold plate is located at the bottom of the cooling chamber and has cooling pipes on its back. The two sets of XYZ modules can cooperate with the two sets of XYZ modules to realize the transportation of the wafer tray between the heating chamber and the cooling chamber, as well as its lifting and lowering within the cooling chamber.

[0012] Furthermore, the heating chamber is provided with an air inlet, the air inlet is connected to an air inlet pipe, and a flow meter is provided on the air inlet pipe.

[0013] Furthermore, the heating chamber is provided with an air extraction port, which is located on the inner wall of the heating chamber and connected to a vacuum tube. The vacuum tube is connected to an external vacuum pump, and a vacuum gauge is provided on the vacuum tube.

[0014] Furthermore, the heating plate is made of graphite, and a heating wire is provided on the back or inside of the graphite plate.

[0015] Furthermore, a transfer window is provided on the cooling chamber.

[0016] Furthermore, a hot plate temperature sensor is installed inside the heating chamber.

[0017] Compared with the prior art, the beneficial effects of this utility model are:

[0018] By inverting the hot plate, the problem of uneven heating in traditional ovens is solved. The high-precision heating plate of this invention can achieve a temperature control accuracy of ±0.1℃. The graphite has high stability and does not exceed the set temperature by more than 0.5℃ during heating. The single-layer photoresist wafer is directly in contact with the heating plate through vacuum adsorption, resulting in fast heat conduction and precise control of the total heating time. The double-layer photoresist wafer achieves heat conduction at a distance that is almost in direct contact with the heating plate by adjusting the height of the gap between it and the heating plate, resulting in better heat uniformity.

[0019] The heating chamber of this invention can be sealed, and inert gas is introduced through the air inlet and air inlet pipe for protection, replacing the oxygen inside, which can significantly reduce bubble defects during high-temperature baking of photoresist.

[0020] This invention utilizes a vacuum vent, vacuum tube, vacuum gauge, and vacuum pump to adjust positive and negative pressures, thereby altering the flowability of the photoresist. When the chamber is under high temperature and high vacuum, the photoresist's internal evaporation rate increases by 10-20 times, causing a high-viscosity cured layer to form on the surface within 10-30 seconds. This hinders the outward diffusion of the internal solvent, creating a hard-shell effect and thus slowing down the photoresist's flow. When the chamber is under high temperature and high pressure, the photoresist's internal evaporation rate slows down to 1 / 10 to 1 / 20 of that at atmospheric pressure, preventing the hard-shell effect caused by premature surface curing. Furthermore, the synergistic effect of high temperature and high pressure reduces the interfacial tension between the photoresist and the substrate, increasing the photoresist's flowability.

[0021] This invention features a cooling chamber with a cold plate inside. He gas is introduced through cooling pipes on the back of the cold plate to maintain its temperature at room temperature (18-24°C). After the wafer is baked, it is placed on the cold plate in the cooling chamber, allowing the photoresist to cool and solidify rapidly, thus inhibiting secondary flow of the photoresist. This rapid cooling reduces the waiting time from several minutes to tens of seconds. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0023] Figure 1 This is a schematic diagram of the structure of a novel inverted heating device;

[0024] Figure 2 This is a schematic diagram of the structure of the XYZ module and the wafer tray.

[0025] The following are marked in the diagram: 1. Heating chamber; 2. Cooling chamber; 3. Door; 4. Heating plate; 5. XYZ module one; 6. XYZ module two; 7. Cold plate; 8. Wafer tray; 9. Air inlet pipe; 10. Vacuum tube; 11. Clamping arm. Detailed Implementation

[0026] In the description of this utility model, it should be noted that the directional terms such as "center", "horizontal (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this utility model.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features. Thus, the use of "first" and "second" to define a feature may explicitly or implicitly include one or more of that feature. In the description of this utility model, "several" or "a number" means two or more, unless otherwise explicitly specified.

[0028] A novel inverted heating device, such as Figure 1-2 As shown, it includes:

[0029] The heating chamber 1 contains a heating module, two sets of XYZ modules 5, and a wafer tray 8. The heating module includes a heating plate 4, which is located at the top of the heating chamber 1 and has several vacuum holes that are connected to an external vacuum pump. Both sets of XYZ modules 5 are connected to clamping arms 11, which can clamp, lift, and transport the wafer tray 8.

[0030] Cooling chamber 2 is located on one side of heating chamber 1 and communicates with heating chamber 1. A door 3 is provided between cooling chamber 2 and heating chamber 1. Cooling chamber 2 is equipped with a cold plate 7 and two sets of XYZ modules 6. The cold plate 7 is located at the bottom of cooling chamber 2 and cooling pipes are provided on the back of the cold plate 7. The two sets of XYZ modules 6 can cooperate with two sets of XYZ modules 5 to realize the transportation of wafer tray 8 between heating chamber 1 and cooling chamber 2 and the lifting and lowering within cooling chamber 2.

[0031] Preferably, the heating chamber 1 is provided with an air inlet, the air inlet is connected to an air inlet pipe 9, and a flow meter is provided on the air inlet pipe 9;

[0032] Specifically, the air inlet vents an inert gas (such as nitrogen or argon) into the heating chamber 1 through the air inlet pipe 9. The flow meter monitors and adjusts the gas flow rate in real time to ensure a stable process atmosphere is formed in the chamber, thereby achieving precise control of the gas environment, avoiding oxidation reactions, and improving the quality of wafer heating. The flow data can be fed back to the control system to achieve automated adjustment and improve process consistency.

[0033] Preferably, the heating chamber 1 is provided with an air extraction hole, which is located on the inner wall of the heating chamber 1 and connected to a vacuum tube 10. The vacuum tube 10 is connected to an external vacuum pump, and a vacuum gauge is provided on the vacuum tube 10.

[0034] Specifically, the gas in the heating chamber 1 is discharged through the evacuation port by a vacuum pump. The vacuum gauge monitors the vacuum level in real time and adjusts the pumping rate in conjunction with the vacuum pump to quickly establish a high vacuum environment and reduce interference from the heat transfer medium. The vacuum level closed-loop control can avoid over-voltage or under-voltage and ensure that the wafer is processed in a uniform thermal field.

[0035] Preferably, the heating plate 4 is made of graphite plate, and a heating wire is provided on the back or inside of the graphite plate. Graphite has high thermal conductivity and high temperature stability. The heating wire embedded inside it achieves rapid and uniform heating through resistance heating, so that the surface temperature uniformity of the graphite plate can reach ±0.1℃, avoiding local overheating. Its high temperature resistance extends its service life and is suitable for long-term continuous operation.

[0036] Preferably, the cooling chamber 2 is provided with a transfer window. By providing the transfer window, the wafer can be placed into or taken out of the cooling chamber 2 through the transfer window. The transfer window can be provided with a transparent high-temperature resistant material (such as quartz glass) to allow an external robotic arm or operator to observe and transfer the wafer.

[0037] Preferably, the heating chamber 1 is also provided with a transfer window for placing the wafer.

[0038] Preferably, a hot plate temperature sensor is installed in the heating chamber 1. By installing the hot plate temperature sensor, the temperature data of the heating plate 4 is collected in real time and fed back to the control system to realize closed-loop control of the temperature of the heating plate 4, so as to avoid overheating or insufficient temperature. The data recording function can trace process parameters and optimize the production process.

[0039] Preferably, the novel inverted heating device further includes a control module, which includes a power supply, electric valves, a PLC controller, a screen, and an electronic motherboard, and performs automated control of each functional mechanism through the control module.

[0040] Work process:

[0041] The wafer is placed on the wafer tray 8 held by two sets of XYZ modules 5 inside the heating chamber 1 through the transfer window, and then the transfer window is closed.

[0042] Gas control is achieved through the control module, and protective gas is introduced into the heating chamber 1 through the air inlet and air inlet pipe 9 while selecting high pressure or low vacuum mode.

[0043] The temperature of the heating plate 4 is adjusted to reach the formula temperature. At the same time, when the gas pressure and gas flow rate in the heating chamber 1 reach the set requirements, the wafer is raised to the set height through the XYZ module-5.

[0044] When performing single-sided homogenization heating with an inverted plate, the vacuum mode is activated, and the wafer is adsorbed onto the heating plate 4, where it is baked. When performing double-sided homogenization heating, the wafer is baked by close-range heat convection and heat radiation between the top surface of the wafer and the heating plate 4.

[0045] After baking, the heating plate 4 is turned off, XYZ module 1 5 moves the wafer tray 8 to the receiving and transfer position, then the vacuum mode is turned off and the wafer is removed. Then the door 3 between the heating chamber 1 and the cooling chamber 2 is opened. With the cooperation of XYZ module 1 5 and XYZ module 2 6, the wafer tray 8 and the wafer are transferred to XYZ module 2 6 and transported into the cooling chamber 2. Then the wafer is placed on the cold plate 7.

[0046] The control module circulates He gas through the cooling pipes on the back of the cold plate 7 to maintain the temperature of the cold plate 7 at room temperature (18-24℃), allowing the wafer to be rapidly cooled by passing through the cold plate 7. After the wafer is cooled, the gas protection is turned off, the inner and outer cylinders are adjusted, and finally the transfer window is opened to remove the wafer.

[0047] advantage:

[0048] 1. By inverting the hot plate, the problem of uneven heating in traditional ovens is solved. The high-precision heating plate 4 of this utility model can achieve a temperature control accuracy of ±0.1℃. The graphite has high stability and does not exceed the set temperature by more than 0.5℃ during heating. The single-layer photoresist wafer is directly in contact with the heating plate 4 through vacuum adsorption, resulting in fast heat conduction and precise control of the total heating time. The double-layer photoresist wafer achieves heat conduction at a distance that is almost in direct contact with the heating plate 4 by adjusting the height of the gap between it and the heating plate 4, resulting in better heat uniformity.

[0049] 2. The heating chamber 1 of this utility model can be sealed, and inert gas is introduced through the air inlet and air inlet pipe 9 for protection, replacing the oxygen inside, which can greatly reduce the bubble defects during high-temperature baking of photoresist.

[0050] 3. This invention uses a vacuum vent, vacuum tube 10, vacuum gauge, and vacuum pump to adjust the positive and negative pressures, thereby changing the flowability of the photoresist. When the chamber is under high temperature and high vacuum, the internal evaporation rate of the photoresist is accelerated by 10-20 times. This causes a high-viscosity curing layer to form on the surface of the photoresist within 10-30 seconds, hindering the outward diffusion of the internal solvent and forming a hard shell effect, thus slowing down the flow of the photoresist. When the chamber is under high temperature and high pressure, the internal evaporation rate of the photoresist is slowed down to 1 / 10 to 1 / 20 of that at atmospheric pressure, avoiding the hard shell effect caused by premature curing of the surface layer. Furthermore, the synergistic effect of high temperature and high pressure can reduce the interfacial tension between the photoresist and the substrate, increasing the flowability of the photoresist.

[0051] 4. This utility model sets up a cooling chamber 2, and a cold plate 7 is set in the cooling chamber 2. He gas is introduced through the cooling pipe on the back of the cold plate 7 to keep the temperature of the cold plate 7 at room temperature (18-24℃). After the wafer baking is completed, it is placed on the cold plate 7 in the cooling chamber 2 to allow the photoresist to cool and solidify quickly, suppressing the secondary flow of the photoresist. The rapid cooling can shorten the waiting time from several minutes to tens of seconds.

[0052] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A novel inverted heating device, characterized in that, include: The heating chamber contains a heating module, two sets of XYZ modules, and a wafer tray. The heating module includes a heating plate located at the top of the heating chamber and has several vacuum holes that are connected to an external vacuum pump. Each of the two sets of XYZ modules is connected to a clamping arm, which allows the two sets of XYZ modules to clamp, lift, and transport the wafer tray. The cooling chamber is located on one side of the heating chamber and communicates with the heating chamber. A door is provided between the cooling chamber and the heating chamber. The cooling chamber contains a cold plate and two sets of XYZ modules. The cold plate is located at the bottom of the cooling chamber and has cooling pipes on its back. The two sets of XYZ modules can cooperate with the two sets of XYZ modules to realize the transportation of the wafer tray between the heating chamber and the cooling chamber, as well as its lifting and lowering within the cooling chamber.

2. The novel inverted heating device according to claim 1, characterized in that: The heating chamber is provided with an air inlet, which is connected to an air inlet pipe, and a flow meter is provided on the air inlet pipe.

3. The novel inverted heating device according to claim 1, characterized in that: The heating chamber is provided with an air extraction port, which is located on the inner wall of the heating chamber and connected to a vacuum tube. The vacuum tube is connected to an external vacuum pump and is equipped with a vacuum gauge.

4. The novel inverted heating device according to claim 1, characterized in that: The heating plate is made of graphite, and a heating wire is provided on the back or inside of the graphite plate.

5. A novel inverted heating device according to claim 1, characterized in that: The cooling chamber is provided with a transfer window.

6. A novel inverted heating device according to claim 1, characterized in that: A hot plate temperature sensor is installed inside the heating chamber.

Images