Imprint lithography equipment and process control methods for preparing etching masks using imprint lithography equipment.

Abstract

This disclosure provides an imprinting apparatus and a process control method for preparing an etching mask using the imprinting apparatus. The process control method includes: during a demolding operation, controlling the imprinting roller to move horizontally from near the first side frame to away from the first side frame while maintaining contact with a rigid transparent substrate; controlling a demolding actuator to drive the first side frame upward; and monitoring the current pressure exerted by the rigid transparent substrate on the imprinting roller; formulating a first speed adjustment strategy based on the current pressure; and executing the first speed adjustment strategy. The first speed adjustment strategy is used to ensure that the subsequent pressure on the imprinting roller is within a preset demolding pressure range. The preset demolding pressure range is a pressure range determined when the distance between the imprinting roller and the demolding separation line is less than a set distance. This disclosure embodiment ensures that the distance between the imprinting roller and the demolding separation line is less than a set distance, thus achieving smoother demolding.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor fabrication technology, specifically to an imprinting apparatus and a process control method for fabricating an etching mask using the imprinting apparatus. Background Technology

[0002] To reduce production costs, some semiconductor device manufacturing processes employ imprinting to create etching masks on wafers. Specifically, a patterned soft film is imprinted onto a substrate coated with photoresist, then the passively patterned photoresist covering the soft film is exposed and cured, and finally the patterned soft film and cured photoresist are demolded and peeled off.

[0003] In the prior art, the imprinting equipment for implementing the aforementioned imprinting method includes a template clamp, a demolding actuator, and an imprinting roller. The patterned flexible film is supported by a transparent film with good elasticity, which is tautly mounted on the template clamp. During the demolding operation using the imprinting equipment, the demolding actuator controls the template clamp to tilt and rise, thereby achieving demolding. Because the transparent film can flexibly deform to ensure demolding pressure, the aforementioned demolding process can be performed smoothly. However, precisely because both the transparent film and the patterned flexible film have good elastic deformation characteristics, the etching mask formed by the aforementioned imprinting process has poor shape reproduction of the pattern on the patterned flexible film, which cannot meet the fabrication requirements of some semiconductor devices.

[0004] To further improve the ability of photoresist layers to reproduce the shape of patterned flexible films, related technologies propose fabricating the flexible film on a rigid transparent substrate with high rigidity but certain deformation characteristics, and using imprinting equipment to achieve etching mask fabrication. However, when using imprinting equipment for demolding, improper coordination between the imprinting rollers and the demolding actuator may lead to problems such as failure to demold properly or breakage of the rigid transparent substrate. These issues require machine maintenance, causing continuous production interruptions and ultimately increasing overall production operating costs. Summary of the Invention

[0005] In a first aspect, embodiments of this disclosure provide a process control method for preparing an etching mask using an imprinting apparatus, the imprinting apparatus comprising a template clamp, an imprinting roller, and a demolding actuator; the template clamp is used to support a rigid transparent substrate with an imprinted pattern on its surface; the demolding actuator is used to drive a first side frame of the template clamp to rise during the demolding operation to achieve tilted demolding; the process control method includes:

[0006] During the demolding operation, the impression roller is controlled to move horizontally from near the first side frame to away from the first side frame while always contacting the rigid transparent substrate. The demolding actuator is controlled to drive the first side frame to rise, and the current pressure of the rigid transparent substrate on the impression roller is monitored.

[0007] A first speed adjustment strategy is formulated based on the current pressure, and the first speed adjustment strategy is executed.

[0008] The first speed adjustment strategy includes adjusting the horizontal moving speed of the impression roller and / or the vertical moving speed of the first side frame; the first speed adjustment strategy is used to ensure that the subsequent pressure of the impression roller is within a preset demolding pressure range, the preset demolding pressure range being the pressure range determined when the distance between the impression roller and the demolding separation line is less than a set distance.

[0009] Optionally, a first velocity adjustment strategy is formulated based on the current pressure, including:

[0010] If the current pressure is less than the lower limit of the preset demolding pressure range, reduce the horizontal moving speed of the impression roller and / or increase the vertical moving speed of the first side frame.

[0011] Optionally, when reducing the horizontal movement speed of the impression roller, the method further includes:

[0012] Determine whether the horizontal movement speed has dropped to zero;

[0013] When the horizontal movement speed drops to zero, the first statistical duration during which the horizontal movement speed remains at zero is recorded.

[0014] If the first statistical duration exceeds the preset duration, an alarm message will be generated.

[0015] Optionally, a first velocity adjustment strategy is formulated based on the current pressure, including:

[0016] If the current pressure is greater than the upper limit of the preset demolding pressure range, reduce the vertical moving speed of the first side frame and / or increase the horizontal moving speed of the impression roller.

[0017] Optionally, when reducing the vertical moving speed of the first side frame, the method further includes:

[0018] Determine whether the vertical moving speed has dropped to zero;

[0019] When the vertical moving speed reaches zero, the second statistical duration during which the vertical moving speed remains at zero is recorded.

[0020] If the second statistical duration exceeds the preset duration, an alarm message will be generated.

[0021] Optionally, if the current pressure is within the preset demolding pressure range, the horizontal moving speed of the impression roller and the vertical moving speed of the first side frame are kept constant, or the vertical moving speed of the impression roller and the vertical moving speed of the first side frame are increased simultaneously.

[0022] Optionally, it also includes: during the demolding operation, monitoring the horizontal distance between the imprinting contact line of the imprinting roller and the vertical plane containing the side of the rigid transparent substrate near the first side frame, and monitoring the vertical movement distance of the rigid transparent substrate near the side frame.

[0023] A second speed adjustment strategy is formulated based on the horizontal distance, the vertical movement distance, the horizontal movement speed of the impression roller, and the vertical movement speed. The second speed adjustment strategy includes adjusting the horizontal movement speed of the impression roller and / or the vertical movement speed of the first side frame. The second speed adjustment strategy is used to ensure that the angle between the plane containing the demolded area and the plane containing the undemolded area of ​​the rigid transparent substrate is less than the maximum allowable angle, where the maximum allowable angle is the maximum bendable angle that ensures the rigid transparent substrate does not undergo plastic deformation.

[0024] A comprehensive adjustment strategy is determined based on the first speed adjustment strategy and the second speed adjustment strategy. This comprehensive adjustment strategy simultaneously ensures that the subsequent pressure applied to the impression roller is within a preset demolding pressure range, and guarantees that the angle between the plane containing the demolded area and the plane containing the undemolded area of ​​the rigid transparent substrate is less than the maximum allowable angle.

[0025] The execution of the first speed adjustment strategy includes: executing the comprehensive adjustment strategy.

[0026] Optionally, it also includes: during the imprinting operation, controlling the imprinting roller to press the rigid transparent substrate down to a preset imprinting depth, maintaining the imprinting pressure within a preset imprinting pressure range, and moving from one side of the rigid transparent substrate to the other side.

[0027] Optionally, it also includes: during the imprinting operation, keeping the photoresist used to form the etching mask within the imprinting temperature range, the imprinting temperature range being the temperature range in which the photoresist maintains the fluidity required to form the imprinted pattern.

[0028] Secondly, this disclosure provides an imprinting apparatus for preparing a wafer etching mask, including a template fixture, an imprinting roller, a demolding actuator, and a controller, as well as a pressure sensor for detecting the pressure on the imprinting roller and a sensor for monitoring the motion state of the imprinting roller and the demolding actuator; the controller adopts the process control method for preparing an etching mask using an imprinting apparatus as described above, to realize process control during the preparation of the etching mask.

[0029] In this embodiment of the present disclosure, the pressure range detected when the impression roller and the demolding separation line are less than a preset distance is used as the preset demolding pressure range. The relationship between the current pressure and the preset demolding pressure range is determined, and a first speed adjustment strategy is formulated based on the aforementioned relationship so that the subsequent pressure on the impression roller is as close as possible to the preset demolding pressure range, and the distance between the impression roller and the demolding separation line is less than the set distance, so as to better achieve smooth demolding. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0031] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without any creative effort, wherein:

[0032] Figure 1 This is a partial flowchart of the process control method provided in the embodiments of this disclosure;

[0033] Figure 2 This is a schematic diagram showing the relative positions of the impression roller and the demolding separation line in one scenario of the demolding process;

[0034] Figure 3 This is a schematic diagram showing the relative positions of the impression roller and the demolding separation line under another scenario during the demolding process;

[0035] Figure 4 This is a partial flowchart of the process control method provided in the embodiments of this disclosure. Detailed Implementation

[0036] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0037] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below. It should be noted that the concepts of "first", "second", etc., used in this disclosure are only used to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies.

[0038] To improve the success rate of demolding in the fabrication of high-fidelity etching masks using imprinting technology with a rigid transparent substrate as the soft film carrier, this disclosure provides a process control method for fabricating etching masks using imprinting equipment.

[0039] To better understand the process control method provided in the embodiments of this disclosure, a simple analysis of the structure of the imprinting equipment is first performed.

[0040] Similar to existing imprinting equipment, the imprinting equipment used in this embodiment includes a wafer carrier platform, a lifting mechanism, a fixture platform, a template fixture, an exposure mechanism, an imprinting mechanism, and a demolding execution mechanism.

[0041] The wafer carrier platform is used to carry wafers on which etching masks need to be prepared; the lifting mechanism is used to lift the fixture platform and / or the exposure mechanism, thereby providing reasonable operating space for picking up and placing wafers on the wafer carrier platform.

[0042] Both the template clamp and the demolding actuator are mounted on the clamping platform. The template clamp is mounted on the clamping platform via lateral positioning and a movable connection. The aforementioned rigid transparent substrate is mounted on the template clamp. In some applications, the edges of the rigid transparent substrate are fixed to the clamping platform. In other embodiments, the rigid transparent substrate is bonded to a softer light-transmitting film, and then the light-transmitting film is fixed to the clamping platform; in this case, the rigid transparent substrate is mounted on the clamping platform, and the deformation of the light-transmitting film can accommodate the conflict between the rigid structures of the rigid transparent substrate and the clamping platform, avoiding deformation of the rigid transparent substrate due to the rigidity conflict between the two.

[0043] The demolding actuator is installed on the lower side of the template fixture. Before the demolding operation is performed, the demolding actuator will not lift the template fixture, and the corresponding template fixture is installed on the fixture support in a horizontal position. During the demolding operation, the demolding actuator will lift the first side frame of the template fixture, so that the first side frame rises and rotates around the second side frame opposite to the first side frame, thereby realizing the tilted demolding of the rigid transparent substrate.

[0044] An imprinting mechanism is mounted on the upper side of the template fixture and includes an imprinting roller. The imprinting roller is used to press against a rigid transparent substrate to perform the imprinting operation and the demolding operation in this embodiment.

[0045] The exposure mechanism is used to expose the photoresist formed by passive imprinting before the imprinting process is completed and the demolding process is executed, so that the photoresist can be cured.

[0046] In addition, necessary sensors are required to implement the aforementioned process control method. These sensors include pressure sensors mounted on the imprinting mechanism to detect the pressure between the imprinting roller and the rigid transparent substrate, and other sensors to measure the moving speed of the imprinting roller and the first side frame of the template fixture. These other sensors can be inertial sensors or displacement sensors that can calculate speed and determine displacement through displacement monitoring.

[0047] In order to achieve process control in the embodiments of this disclosure, the power device for controlling the action of the impression roller and the demolding actuator in the impression mechanism should be a device with adjustable speed capability.

[0048] Figure 1 This is a partial flowchart of the process control method provided in the embodiments of this disclosure. Figure 1 The partial flowchart shown illustrates the process control methods during the demolding operation. For example... Figure 1 As shown, the process control methods during the demolding operation include S110-S120.

[0049] S110: Control the impression roller to move horizontally from near the first side frame to away from the first side frame while always contacting the rigid transparent substrate, control the demolding actuator to drive the first side frame to rise, and monitor the current pressure of the rigid transparent substrate acting on the impression roller.

[0050] Before the demolding operation begins, the impression roller has moved to the side of the rigid transparent substrate near the first side frame of the template fixture and abuts against the rigid transparent substrate. After the demolding operation begins, the controller controls the impression roller and the demolding actuator to perform specific actions respectively to achieve the demolding separation of the rigid transparent substrate and the solidified etching mask (which may also include the wafer): (1) the impression roller is controlled to move horizontally from near the first side frame to away from the first side frame while maintaining contact with the rigid transparent substrate; (2) the demolding actuator is controlled to drive the first side frame of the template fixture to rotate and rise.

[0051] Furthermore, during the operation of controlling the horizontal movement of the impression roller, the impression roller is no longer actively applied to the rigid transparent substrate; instead, it passively bears the pressure generated by the rigid transparent substrate. Of course, if the movement speed of the impression roller is not coordinated with the speed at which the demolding actuator drives the first side frame to rise, and the rigid roller moves too slowly, it can also be understood that the aforementioned pressure is caused by the impression roller.

[0052] During the aforementioned operation, the pressure sensor detects the current pressure exerted on the impression roller by the rigid transparent substrate during the demolding process.

[0053] S120: Formulate a first speed adjustment strategy based on the current pressure and execute the first speed adjustment strategy.

[0054] In this embodiment of the disclosure, the first speed adjustment strategy is to adjust the moving speed of the impression roller and the first side frame, thereby achieving the most accurate demolding of the subsequent rigid transparent substrate and photocured etching mask. The first speed adjustment strategy includes a sub-strategy of adjusting the horizontal moving speed of the impression roller, a sub-strategy of adjusting the vertical moving speed of the first side frame, and a combination of the two strategies.

[0055] In this embodiment of the present disclosure, the first speed adjustment strategy is used to ensure that the subsequent pressure applied to the impression roller is within a preset demolding pressure range. The preset demolding pressure range is predetermined and is a pressure range determined when the distance between the impression roller and the demolding separation line is less than a set distance interval.

[0056] Figure 2 This is a schematic diagram showing the relative positions of the impression roller and the demolding separation line in one scenario of the demolding process; Figure 3 This is a schematic diagram showing the relative positions of the impression roller and the demolding separation line under another scenario during the demolding process.

[0057] like Figure 2 As shown, in some cases, due to the relatively low horizontal movement speed of the impression roller (and possibly the relatively high vertical movement speed of the first side frame), the contact line between the impression roller and the rigid transparent substrate is located between the demolding separation line and the disengagement actuator. In this case, the pressure exerted by the rigid transparent substrate on the impression roller is relatively high due to the demolding operation.

[0058] like Figure 3 As shown, in some other cases, due to the relatively high horizontal movement speed of the impression roller (or possibly because the relatively low vertical movement speed of the first side frame), the demolding separation line is located between the contact line between the impression roller and the rigid transparent substrate and the disengagement actuator. In this case, because the rigid transparent substrate in contact with the impression roller does not deform by detaching from the etching mask, the pressure exerted by the rigid transparent substrate on the impression roller is relatively small.

[0059] In the foregoing Figure 2In this case, because the impression roller restricts the movement of the release line between the rigid transparent substrate and the etching mask, normal demolding of the rigid transparent substrate is restricted. And... Figure 3 In the scenario shown, since the impression roller is not pressed against the demolding separation line, the peeling force generated by the demolding actuator needs to overcome the bonding force between the large-area etching mask and the rigid transparent substrate to achieve demolding. That is, in Figure 2 and Figure 3 In both cases, neither the rigid transparent substrate nor the etching mask can achieve good demolding.

[0060] Combination Figure 2 and Figure 3 If the contact line between the impression roller and the rigid transparent substrate is close to the demolding separation line (ideally, the contact line between the impression roller and the rigid transparent substrate is directly above the demolding separation line), the impression roller rests against the rigid transparent substrate, so that the peeling force generated by the demolding actuator is applied precisely to a small area near the demolding separation line, and the impression roller does not obstruct the demolding process. At this time, the pressure on the impression roller (i.e., the current pressure) is less than... Figure 1 The pressure experienced in the situation shown is greater than that described above. Figure 3 The pressure under the conditions shown.

[0061] Based on the foregoing considerations, in this embodiment of the present disclosure, the pressure range detected when the impression roller and the demolding separation line are less than a preset distance is used as the preset demolding pressure range. The relationship between the current pressure and the preset demolding pressure range is determined, and a first speed adjustment strategy is formulated based on the aforementioned relationship, so that the subsequent pressure on the impression roller is as close as possible to the preset demolding pressure range, thereby making the distance between the impression roller and the demolding separation line less than the set distance, and better achieving smooth demolding.

[0062] In practice, the initial speed adjustment strategy is formulated based on the current pressure, which needs to be determined according to the current pressure and the preset demolding pressure range. Specifically, this includes the following three scenarios.

[0063] The first scenario: when the current pressure is less than the lower limit of the preset demolding pressure range, that is... Figure 3 The pressure conditions are shown in the diagram. In this case, the impression roller needs to wait for the demolding separation line to move closer to itself. The corresponding control strategies can be: (1) reduce the horizontal movement speed of the impression roller; (2) increase the vertical movement speed of the first side frame, that is, increase the upward movement speed of the demolding actuator; (3) reduce the horizontal movement speed of the impression roller while increasing the vertical movement speed of the first side frame. In specific implementation, considering that a single control can achieve better control effect, the aforementioned control strategies (1) or (2) are preferred.

[0064] The second scenario: when the current pressure exceeds the preset demolding pressure range, that is... Figure 2 The pressure conditions are shown in the diagram. Under these conditions, the corresponding control strategies can be: (1) increasing the horizontal movement speed of the impression roller; (2) decreasing the vertical movement speed of the first side frame, that is, decreasing the upward movement speed of the demolding actuator; (3) increasing the horizontal movement speed of the impression roller while decreasing the vertical movement speed of the first side frame. In practice, considering that a single control can achieve better control results, it is preferable to adopt the aforementioned control strategies (1) or (2).

[0065] In practical applications, template fixtures are usually placed directly on the fixture support by gravity and positioned and placed by vertical positioning pins without vertical limit. Due to the limitations of existing wafer processing technology, the wafers coated with etching masks are all circular wafers. During the demolding operation, the demolding separation line gradually increases first, and then gradually decreases after reaching its maximum value. In practical applications, if the moving speed of the first side frame is kept constant and the horizontal moving speed of the imprinting roller is increased, if the demolding separation line gradually decreases after reaching its maximum value, the peeling force may suddenly increase. In the case of a sudden increase in peeling force, since the template fixture has no vertical positioning limit, the peeling force may lift the template fixture, causing it to bounce up and detach from the vertical positioning pin, without returning to its correct position. At this time, the vertical positioning pin cannot detect the template fixture and assumes that no template fixture is placed in the imprinting equipment. By reducing the vertical moving speed of the first side frame as described above (2), the problem of the imprinting template bouncing up and detaching from the vertical positioning pin due to the excessive vertical moving speed of the first side frame can also be avoided.

[0066] The third scenario: The current pressure is within the preset demolding pressure range. In this scenario, the horizontal movement speed of the impression roller and the vertical movement speed of the first side frame are coordinated, and the following operations can be performed: (1) Keep the horizontal movement speed of the impression roller and the vertical movement speed of the first side frame unchanged; (2) Simultaneously increase the vertical movement speed and horizontal movement speed of the impression roller. In specific implementation, (1) can be performed when either the horizontal movement speed of the impression roller or the vertical movement speed of the first side frame has reached the maximum feasible speed, and (2) can be performed when neither the horizontal movement speed of the impression roller nor the vertical movement speed of the first side frame has reached the maximum feasible speed, so as to maximize the time consumed by a single impression operation of the impression equipment.

[0067] In practical applications, reducing the horizontal movement speed of the impression roller may result in an extreme situation where the horizontal movement speed drops to zero. However, this extreme situation is relatively rare and is mostly caused by malfunctions during the demolding process of the impression equipment. This is because the impression equipment operates automatically under normal circumstances, and manual intervention is required to resolve equipment malfunctions.

[0068] Accordingly, in order to identify faults in the demolding process of the printing equipment by the horizontal movement speed of the impression roller, the process control method may also include the following steps S130-S150 when the horizontal movement speed of the impression roller is reduced as described above.

[0069] S130: Determine if the horizontal movement speed has decreased to zero; if yes, execute S140; otherwise, execution ends.

[0070] S140: The first statistical duration during which the statistical horizontal moving speed remains at zero.

[0071] S150: If the first statistical duration exceeds the preset duration, generate an alarm message.

[0072] In practice, if the horizontal movement speed of the impression roller remains at zero for an extended period, according to the aforementioned logical analysis, it can be inferred that the separation line between the rigid transparent substrate and the etched layer has not moved. However, this situation is abnormal. Therefore, if it is determined that the horizontal movement speed remains at zero for more than a preset time, an alarm message will be generated to prompt manual intervention by the machine operator.

[0073] Similar to the previous analysis, reducing the vertical movement speed of the first side frame may result in an extreme situation where the vertical movement speed of the first side frame drops to zero. However, the probability of this extreme situation occurring is very small, and it is most likely caused by a malfunction during the demolding process of the printing equipment. Accordingly, in order to identify malfunctions in the printing equipment during the demolding process through the vertical movement speed of the first side frame, the process control method, when implementing the reduction of the vertical movement speed of the first side frame as described above, may further include the following steps S160-S180.

[0074] S160: Determine if the vertical movement speed has dropped to zero; if yes, execute S170; otherwise, execution ends.

[0075] S170: The second statistical duration during which the vertical moving speed remains at zero.

[0076] S180: If the second statistical duration exceeds the preset duration, generate an alarm message.

[0077] In practice, if the vertical movement speed of the impression roller remains at zero for an extended period, according to the aforementioned logical analysis, it can be deduced that the impression roller is continuously pressing against the part of the rigid transparent substrate that has detached, and is located far from the demolding separation line. This situation is abnormal. Therefore, if it is determined that the vertical movement speed remains at zero for more than a preset time, an alarm message will be generated to prompt manual intervention by the machine operator.

[0078] As analyzed above, because the rigid transparent substrate has high rigidity, if the rigid transparent substrate deforms too much during the demolding process, it may cause plastic deformation, resulting in the inability to restore its original shape or breakage, thus rendering the imprinted soft film on it unusable. Figure 4 This is a partial flowchart of the process control method provided in the embodiments of this disclosure. Figure 4 As shown, in some embodiments of this disclosure, the following steps S210-S230 are also performed during the demolding operation.

[0079] S210: Monitor the horizontal distance between the imprinting contact line of the imprinting roller and the vertical plane containing the side of the rigid transparent substrate near the first side frame, and monitor the vertical movement distance of the rigid transparent substrate near the side frame.

[0080] S220: Formulate a second speed adjustment strategy based on the horizontal distance, vertical movement distance, horizontal movement speed of the impression roller, and vertical movement speed of the first side frame.

[0081] by Figure 2 For example, point A in the diagram represents the contact line of the impression roller (assuming it is close to the demolding separation line, its position is the location of the demolding analysis line), and point B represents the side of the rigid transparent substrate near the first side frame. The corresponding horizontal distance is the distance between points A and C in the diagram, and the vertical movement distance is the distance between points B and C. Because the line containing AC is parallel to the unpeeled portion of the rigid transparent substrate, the angle between AC and AB represents the deformation angle of the rigid transparent substrate. The aforementioned angle will dynamically change with the horizontal movement speed of the impression roller and the vertical movement speed of the first side frame.

[0082] Preliminary verification revealed that if a rigid transparent substrate is bent to a certain maximum angle, it will undergo plastic deformation and cannot return to its initial shape, thus rendering it unsuitable for subsequent imprinting. This aforementioned maximum angle was set as the maximum allowable angle.

[0083] A second speed control strategy is formulated based on the horizontal distance, vertical movement distance, and the horizontal and vertical movement speeds of the impression roller to ensure that the angle between the plane containing the demolded area and the plane containing the undemolded area of ​​the rigid lens substrate is less than the maximum allowable angle. In other words, the purpose of using the second speed adjustment strategy is to always maintain the angle between AC and AB less than the maximum allowable angle.

[0084] After determining the second adjustment strategy, S230 is then executed.

[0085] S230: Determine the comprehensive adjustment strategy based on the first speed adjustment strategy and the second speed adjustment strategy.

[0086] The comprehensive adjustment strategy is to simultaneously ensure that the subsequent pressure applied by the impression roller is within the preset demolding pressure range, and that the angle between the plane containing the demolded area and the plane containing the undemolded area of ​​the rigid transparent substrate is less than the maximum allowable angle. In specific implementation, the strategy that simultaneously satisfies the aforementioned requirements between the first speed adjustment strategy and the second speed adjustment strategy can be selected as the comprehensive adjustment strategy.

[0087] When executing the aforementioned S210-S230, the execution of the first speed adjustment strategy in the aforementioned S120 specifically refers to the execution of the comprehensive adjustment strategy.

[0088] The preceding text analyzed the process control methods during demolding. In addition, the process control methods also ensure control during the embossing process. Specifically, this includes S310 as follows.

[0089] S310: During the imprinting operation, after controlling the imprinting roller to press the rigid transparent substrate to the preset imprinting depth, the imprinting pressure is kept within the preset imprinting pressure range, and the roller moves from one side of the rigid transparent substrate to the other side.

[0090] In practice, the wafer for which the etching mask needs to be prepared is first placed on a wafer carrier platform and coated with photocurable adhesive. Then, the fixture platform and template fixture are lowered so that the rigid transparent substrate rests against the photocurable-coated wafer. Next, the imprinting roller is controlled to press against the rigid transparent substrate to a preset imprinting depth, maintaining the imprinting pressure within a preset imprinting pressure range, and moving from one side of the rigid transparent gradient to the other side to imprint the rigid transparent substrate, thereby filling the patterned cutout areas on the rigid transparent substrate with photocurable adhesive.

[0091] In practice, in order to ensure that the photoresist is within a reasonable imprinting fluidity range, that is, it will not fail to fill the image cutout area due to excessive fluidity, nor will it fail to imprint the pattern correctly due to insufficient fluidity, the following S320 will also be executed during the execution of the aforementioned S310.

[0092] S320: Keep the photoresist used to form the etching mask within the imprinting temperature range.

[0093] In practice, the imprinting temperature range is the temperature range within which the photoresist maintains the reasonable imprinting fluidity required to form the imprinted pattern. The imprinting temperature range is determined based on the type and performance parameters of the photoresist used.

[0094] After completing the control steps S310-S320, the exposure mechanism can then be controlled to perform exposure operations according to reasonable exposure process parameters to achieve photoresist curing. After the photoresist has cured, the process control method for the demolding operation described above can be executed to achieve demolding and peeling of the rigid transparent substrate from the photoresist.

[0095] In addition to providing the aforementioned process control method, this disclosure also provides an imprinting apparatus for implementing the aforementioned process control method. The imprinting apparatus includes, in addition to the aforementioned execution hardware (i.e., a template clamp, an imprinting roller, a demolding mechanism, a pressure sensor for detecting the pressure applied to the imprinting roller, and sensors for monitoring the motion states of the imprinting roller and the demolding mechanism), a controller; the controller employs the aforementioned process control method to achieve process control during the etching mask preparation process.

[0096] In a specific application, for a photomask product of a certain thickness, the ideal pressure range during the imprinting process is [P1, P2], the temperature range is [T1, T2], and the imprinting depth is D; the ideal pressure range during demolding is [P3, P4], the warning pressure range during demolding is [P5, P6], the temperature range is [T3, T4], and the demolding waiting time is S1.

[0097] During the printing process, the printing equipment executes steps S310 and S320 as described above, based on the aforementioned ideal pressure and temperature ranges, to achieve the printing operation, and exposes for time S1 after printing. During the demolding process, the actions of the printing roller and the demolding actuator are controlled, and the actual pressure on the printing roller is monitored. When the actual pressure is less than P3 but greater than P5, the horizontal movement speed of the printing roller is reduced; when the actual pressure is between P3 and P4, the horizontal movement speed of the printing roller and the vertical movement speed of the demolding actuator are gradually increased until the maximum allowable demolding speed is reached; when the actual pressure is greater than P5 but less than P6, the vertical movement speed of the demolding actuator is reduced. According to the method described above, if the running speed of either the printing roller or the demolding actuator drops to zero and remains at a preset value for a preset duration during the demolding operation, an alarm message is generated.

[0098] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0099] The above are merely specific embodiments of this disclosure, enabling those skilled in the art to understand or implement this disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to these embodiments, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A process control method for preparing an etching mask using an imprinting device, characterized in that, The embossing equipment includes a template clamp, an embossing roller, and a demolding mechanism; the template clamp is used to support a rigid transparent substrate with an embossed pattern on its surface; the demolding mechanism is used to drive the first side frame of the template clamp to rise during the demolding operation to achieve tilted demolding; the process control method includes: During the demolding operation, the impression roller is controlled to move horizontally from near the first side frame to away from the first side frame while always contacting the rigid transparent substrate. The demolding actuator is controlled to drive the first side frame to rise, and the current pressure of the rigid transparent substrate on the impression roller is monitored. A first speed adjustment strategy is formulated based on the current pressure, and the first speed adjustment strategy is executed. The first speed adjustment strategy includes adjusting the horizontal moving speed of the impression roller and / or the vertical moving speed of the first side frame; the first speed adjustment strategy is used to ensure that the subsequent pressure of the impression roller is within a preset demolding pressure range, the preset demolding pressure range being the pressure range determined when the distance between the impression roller and the demolding separation line is less than a set distance.

2. The process control method according to claim 1, characterized in that, Based on the current pressure, a first velocity adjustment strategy is formulated, including: If the current pressure is less than the lower limit of the preset demolding pressure range, reduce the horizontal moving speed of the impression roller and / or increase the vertical moving speed of the first side frame.

3. The process control method according to claim 2, characterized in that, When reducing the horizontal movement speed of the impression roller, the method further includes: Determine whether the horizontal movement speed has dropped to zero; When the horizontal movement speed drops to zero, the first statistical duration during which the horizontal movement speed remains at zero is recorded. If the first statistical duration exceeds the preset duration, an alarm message will be generated.

4. The process control method according to claim 1, characterized in that, Based on the current pressure, a first velocity adjustment strategy is formulated, including: If the current pressure is greater than the upper limit of the preset demolding pressure range, reduce the vertical moving speed of the first side frame and / or increase the horizontal moving speed of the impression roller.

5. The process control method according to claim 4, characterized in that, When reducing the vertical moving speed of the first side frame, the method further includes: Determine whether the vertical moving speed has dropped to zero; When the vertical moving speed reaches zero, the second statistical duration during which the vertical moving speed remains at zero is recorded. If the second statistical duration exceeds the preset duration, an alarm message will be generated.

6. The process control method according to claim 1, characterized in that, When the current pressure is within the preset demolding pressure range, the horizontal moving speed of the impression roller and the vertical moving speed of the first side frame are kept constant, or the vertical moving speed of the impression roller and the vertical moving speed of the first side frame are increased simultaneously.

7. The process control method according to any one of claims 1-6, characterized in that, Also includes: During the demolding operation, the horizontal distance between the imprinting contact line of the imprinting roller and the vertical plane of the side of the rigid transparent substrate near the first side frame is monitored, as well as the vertical movement distance of the rigid transparent substrate near the side frame. A second speed adjustment strategy is formulated based on the horizontal distance, the vertical movement distance, the horizontal movement speed of the impression roller, and the vertical movement speed. The second speed adjustment strategy includes adjusting the horizontal movement speed of the impression roller and / or the vertical movement speed of the first side frame. The second speed adjustment strategy is used to ensure that the angle between the plane containing the demolded area and the plane containing the undemolded area of ​​the rigid transparent substrate is less than the maximum allowable angle, where the maximum allowable angle is the maximum bendable angle that ensures the rigid transparent substrate does not undergo plastic deformation. A comprehensive adjustment strategy is determined based on the first speed adjustment strategy and the second speed adjustment strategy. This comprehensive adjustment strategy simultaneously ensures that the subsequent pressure applied to the impression roller is within a preset demolding pressure range, and guarantees that the angle between the plane containing the demolded area and the plane containing the undemolded area of ​​the rigid transparent substrate is less than the maximum allowable angle. The execution of the first speed adjustment strategy includes: executing the comprehensive adjustment strategy.

8. The process control method according to any one of claims 1-6, characterized in that, Also includes: During the imprinting operation, the imprinting roller is controlled to press the rigid transparent substrate down to a preset imprinting depth, and the imprinting pressure is kept within the preset imprinting pressure range, and then moved from one side of the rigid transparent substrate to the other side.

9. The process control method according to claim 8, characterized in that, Also includes: During the imprinting operation, the photoresist used to form the etching mask is kept within the imprinting temperature range, which is the temperature range that allows the photoresist to maintain the fluidity required to form the imprinted pattern.

10. An imprinting apparatus for preparing a wafer etching mask, characterized in that, It includes a template clamp, an impression roller, a demolding actuator and a controller, as well as a pressure sensor for detecting the pressure on the impression roller and a sensor for monitoring the motion state of the impression roller and the demolding actuator; the controller adopts the process control method for preparing an etching mask using an impression device as described in any one of claims 1-9, to realize process control in the preparation of the etching mask.

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