Photoetching illumination system and method and photoetching machine

Abstract

The invention discloses a photoetching illumination system and method and a photoetching machine, and relates to the technical field of photoetching, the photoetching illumination system comprises an asymmetric optical splitter, a monitor, an exposure device, a preset light source and a controller; the preset light is divided into the monitoring light transmitted to the monitor and the illumination light transmitted to the exposure device through the asymmetric optical splitter, and the controller can obtain the light field distribution of the illumination light through the light field distribution of the monitoring light obtained by the monitor, so that the monitoring effect is achieved. Meanwhile, when the controller judges that the light field distribution of the illumination light is abnormal, the light source pixel parameters corresponding to the preset light output by the preset light source can be adaptively adjusted, so that the generated illumination light continues to achieve the uniform light effect. Through the simple structure, the integration of dodging and monitoring of the photoetching illumination system is realized, the hardware structure complexity of the whole photoetching illumination system is greatly reduced, and the interference on the photoetching illumination system caused by the condition that the light source is unstable is reduced.

Description

Technical Field

[0001] The present application relates to the field of photolithography technology, and in particular to a photolithography illumination system, method and photolithography machine. Background Art

[0002] In the prior art, the lithography illumination system is one of the core subsystems of the deep ultraviolet (DUV) lithography machine. Its main function is to achieve uniform illumination on the mask surface and multiple illumination modes on the pupil surface, so as to ensure that the lithography machine can obtain uniform resolution in the exposure field. Since the exposure process has extremely high requirements for illumination uniformity, the traditional DUV lithography illumination system needs to introduce a more complex compound eye homogenization device or a quartz rod waveguide homogenization device to homogenize the light in order to adjust the light field energy distribution of the light source. However, it does not have the function of monitoring the light field energy distribution and adaptively adjusting the homogenization effect. Once the light field of the illumination light cannot meet the working requirements, it is difficult to detect in time, which can easily cause significant losses. Even if it can be discovered in time, it is necessary to replace the hardware and readjust the parameters of the entire lithography illumination system before it can continue to be used. Not only does it lead to a complex structure of the entire lithography illumination system, but it is also difficult to solve the interference caused by the unstable operation of the light source. Summary of the invention

[0003] The main purpose of the present application is to provide a lithography illumination system, method and lithography machine, aiming to solve the technical problem of how to realize the integration of uniform light and monitoring in the lithography illumination system, thereby reducing the hardware structure complexity of the entire lithography illumination system and reducing the interference of the unstable light source on the operation of the entire system.

[0004] To achieve the above-mentioned purpose, an embodiment of the present application provides a resonance control device, wherein the photolithography illumination system comprises: an asymmetric beam splitter, a monitor, an exposure device, a preset light source and a controller; The controller is electrically connected to the monitor and the preset light source respectively; The asymmetric beam splitter is arranged on the light output path of the preset light source, and is used to refract and reflect the preset light emitted by the preset light source, generate monitoring light and illumination light on different light paths, and transmit the monitoring light to the monitor, and transmit the illumination light to the exposure device at the same time; The exposure device is used to perform exposure processing on the wafer to be processed based on the acquired illumination light; The monitor is used to monitor the light field distribution data of the monitoring light and transmit the corresponding light field information to the controller; The controller is used to send a uniform light control signal to the preset light source based on the light field information; The preset light source is used to adjust the light source pixel parameters of the preset light based on the uniform light control signal.

[0005] In one embodiment, one surface of the asymmetric beam splitter is disposed toward the preset light source to receive the preset light and reflect the illumination light, and another surface of the asymmetric beam splitter is used to refract the monitoring light.

[0006] In one embodiment, one surface of the asymmetric beam splitter is disposed toward the preset light source to receive the preset light and reflect the monitoring light, and another surface of the asymmetric beam splitter is used to refract the illumination light.

[0007] In one embodiment, a dielectric layer and a functional layer are provided between two surfaces of the asymmetric beam splitter; The dielectric layer is made of isotropic homogeneous material or anisotropic material; The functional layer is made of metal material or optical medium material.

[0008] In one embodiment, one surface of the asymmetric beam splitter is a smooth surface covered with an optical coating.

[0009] In one embodiment, the asymmetric beam splitter is further used to, when receiving the preset light, perform decorrelation processing on the preset light to obtain the illumination light, and transmit the illumination light to the exposure device.

[0010] In one embodiment, the exposure device comprises: a mask work stage, a projection lens system, a wafer work stage and a calibration stage; The mask workpiece stage is used to carry the mask plate; The projection objective lens system is used to change the projection pattern of the received illumination light through the mask, and focus the illumination light to the wafer to be processed through the objective lens group; Wherein, the wafer worktable is used to carry the wafer to be processed; and the calibration table is used to calibrate the relative position between the mask and the wafer to be processed.

[0011] In one embodiment, the mask and the wafer worktable are arranged in any one of a contact type, a proximity type and a projection type.

[0012] In addition, to achieve the above-mentioned purpose, the present application also proposes a lithography illumination method, which is applied to the lithography illumination system as described above, and the steps of the lithography illumination method include: Controlling a preset light source to emit preset light to the asymmetric beam splitter, and obtaining light field information corresponding to the monitoring light generated by the asymmetric beam splitter through a monitor, while causing an exposure device to perform exposure through the illumination light generated by the asymmetric beam splitter; Based on the light field information, the preset light source is controlled to adjust the light source pixel parameters of the preset light, so as to adjust the illumination light.

[0013] In addition, to achieve the above objectives, the present application also provides a lithography machine, which adopts the lithography illumination system described above.

[0014] The embodiments of the present application provide a lithography illumination system, method and lithography machine, wherein the lithography illumination system comprises: an asymmetric beam splitter, a monitor, an exposure device, a preset light source and a controller; the controller is electrically connected to the monitor and the preset light source respectively; the asymmetric beam splitter is arranged on the light output path of the preset light source, and is used to refract and reflect the preset light emitted by the preset light source, generate monitoring light and illumination light on different light paths respectively, and transmit the monitoring light to the monitor, and transmit the illumination light to the exposure device at the same time; the exposure device is used to perform exposure processing on a wafer to be processed based on the acquired illumination light; the monitor is used to monitor the light field distribution data of the monitoring light, and transmit the corresponding light field information to the controller; the controller is used to send a uniform light control signal to the preset light source based on the light field information; the preset light source is used to adjust the light source pixel parameters of the preset light based on the uniform light control signal. The preset light is divided into monitoring light transmitted to the monitor and illumination light transmitted to the exposure device by an asymmetric beam splitter. The controller can obtain the light field distribution of the illumination light through the light field distribution of the monitoring light obtained by the monitor, thereby achieving the monitoring effect. At the same time, when the controller determines that the light field distribution of the illumination light is abnormal, it can adaptively adjust the light source pixel parameters corresponding to the preset light output by the preset light source, so that the generated illumination light continues to achieve the uniform light effect. The above simple structure realizes the integration of uniform light and monitoring of the lithography illumination system, greatly reducing the complexity of the hardware structure of the entire lithography illumination system, and reducing the interference of the unstable light source to the lithography illumination system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0017] Figure 1 A schematic diagram of the structure of the first embodiment of the lithography illumination system of the present application; Figure 2 A schematic diagram of the modulation of illumination brightness and polarization state corresponding to the output of preset light by a preset light source; Figure 3 is a structural diagram of an asymmetric beam splitter; Figure 4 This is the optical path diagram when the asymmetric beam splitter works; Figure 5 A schematic diagram of a process flow provided for Embodiment 1 of the photolithography illumination method of the present application; Figure 6 Another schematic diagram of a process flow provided for the first embodiment of the photolithography illumination method of the present application; Figure 7 Schematic diagram of illumination light field distribution.

[0018] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0019] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0020] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0021] This application proposes a first embodiment of a lithography illumination system, please refer to Figure 1 , the photolithography illumination system comprises: an asymmetric beam splitter 10, a monitor 20, an exposure device 30, a preset light source 40 and a controller 50; The controller 50 is electrically connected to the monitor 20 and the preset light source 40 respectively; The asymmetric beam splitter 10 is disposed on the light output path of the preset light source 40, and is used to refract and reflect the preset light emitted by the preset light source 40, generate monitoring light and illumination light on different light paths, and transmit the monitoring light to the monitor 20, while transmitting the illumination light to the exposure device 30; The exposure device 30 is used to perform exposure processing on the wafer to be processed based on the acquired illumination light; The monitor 20 is used to monitor the light field distribution data of the monitoring light and transmit the corresponding light field information to the controller 50; The controller 50 is used to send a uniform light control signal to the preset light source based on the light field information; The preset light source 40 is used to adjust the light source pixel parameters of the preset light based on the uniform light control signal.

[0022] It should be noted that, in this embodiment, the controller 50 actually refers to an electronic device having functions such as data processing and control, which may be a server, or an electronic terminal device such as a smart phone, a personal computer (PC), a tablet computer, a portable computer, etc. The controller 50 may send a control signal or a control instruction such as a uniform light control signal that may control the working state of the preset light source 40 to control the working state of the preset light source 40.

[0023] It should be understood that the preset light source 40 can specifically be a pixel-level controllable light source array, which includes at least one light-emitting subunit, and the light-emitting subunit can be any one of light-emitting diodes (LED), organic light-emitting diodes (OLED), quantum dot light-emitting diodes (QLED), and micro light-emitting diodes (Micro LED). The exposure wavelength of each of the light-emitting subunits is a wavelength with a higher photosensitivity response, and the light emitted by each of the light-emitting subunits includes but is not limited to a central wavelength of a deep ultraviolet wavelength; the brightness (including on / off state) and polarization state of each pixel of the light source are modulated as follows: Figure 2 As shown, each pixel can be added with a large-aperture electrically controlled polarizer to unify the polarization state change, or add a pixel-level liquid crystal spatial light modulator to customize the polarization state change of a single pixel, similar to the light intensity waveforms corresponding to light source pixel 1, light source pixel 2, and light source pixel 3 in the figure. In this embodiment, the light source pixel parameter can be understood as the light parameter of the preset light emitted by the preset light source 40 at the pixel level.

[0024] It should be noted that, in the present embodiment, the asymmetric beam splitter 10 can adopt a bidirectional anisotropy design so that its reflection characteristics and transmission characteristics can be adjusted independently. Bidirectional anisotropy refers to a special physical property, in which there is a phenomenon of electromagnetic coupling between the electric field and the magnetic field, that is, the electric field can cause magnetization, and the magnetic field can cause electric polarization. The bidirectional anisotropy can be used to adjust the transmission path of light. It can be set on the light output path of the preset light emitted by the preset light source 40, and the corresponding monitoring light and the corresponding illumination light are generated through its transmission characteristics and reflection characteristics. Since the input light is the preset light of the same source and the light modulation characteristics of the asymmetric beam splitter 10 itself are fixed, the light field distribution characteristics of the monitoring light and the illumination light are similar, and can be estimated based on the modulation function designed by the asymmetric beam splitter 10 itself.

[0025] It is easy to understand that, in the initial state, the preset light source 40 can first send the initial preset light to the asymmetric beam splitter 10. After receiving the preset light, the asymmetric beam splitter 10 sends the monitoring light to the monitor 20 after refraction or reflection, and sends the illumination light to the exposure device 30 after reflection or refraction. The monitor 20 can monitor the received monitoring light, so as to obtain the light field distribution data of the monitoring light, and transmit the light field distribution data to the controller 50 in the form of light field information. When the controller 50 receives the light field information, it can obtain the light field distribution data of the illumination light through the light field distribution data of the monitoring light. Subsequently, the light field distribution data of the currently obtained illumination light is analyzed to determine whether the illumination uniformity corresponding to the currently sent preset light meets the requirements, so as to determine whether the light source pixel parameters of the preset light source 40 need to be adjusted. If it is determined that the illumination uniformity does not meet the requirements, the corresponding uniform light control signal can be sent to control the operating state of the light source pixel of the preset light source 40, including the intensity, phase and amplitude distribution of the preset light. In this way, the light parameters of the illumination light received by the exposure device 30 are changed, so that the exposure device 30 can perform exposure processing on the object to be processed with the optimal light parameters.

[0026] Among them, the controller 50 reads the light field distribution data of the received monitoring light sent by the monitor 20, and determines the light field information corresponding to the illumination light reaching the exposure device 30 through the intelligent core algorithm, and then uses the learning and training results to determine the combination of each point light source in the preset light source 40, finds the array combination that realizes the ideal uniform light effect and issues instructions to the light source, thereby realizing a lithography illumination system that integrates monitoring and uniform light.

[0027] It is worth noting that, in the present embodiment, the monitor 20 includes a device for receiving optical signals, including but not limited to a camera, a photodiode, an avalanche photodiode sensor, etc., which are arranged based on complementary metal oxide semiconductor and charge coupled device sensors.

[0028] Further, in this embodiment, please refer to Figure 1 As shown in the left figure, as a specific case, one surface of the asymmetric beam splitter 10 is arranged toward the preset light source 40 to receive the preset light and reflect the illumination light, and the other surface of the asymmetric beam splitter 10 is used to refract the monitoring light.

[0029] It should be noted that, in this embodiment, the asymmetric beam splitter 10 can receive incident light generated by the preset light source 40, i.e., the preset light, through one surface thereof. The preset light can sequentially reach the two surfaces of the asymmetric beam splitter 10 along its incident direction, and both surfaces are used to reflect and refract the preset light, so as to emit light beams from the two surfaces respectively. Figure 3One surface of the asymmetric beam splitter 10 can be a smooth ordinary optical surface (smooth surface), and the other surface can be a special optical surface (diffuse reflection surface). The optical paths of the light refracted by the ordinary optical surface and the special optical surface are consistent, and will be modulated into monitoring light and refracted to the monitor 20. The light reflected by the special optical surface will form decoherent illumination light due to the diffuse reflection modulation and / or diffuse light modulation optical path and will be reflected to the exposure device 30.

[0030] It is worth noting that in the present embodiment, one surface (smooth surface) of the asymmetric beam splitter 10 can be coated with an optical coating for adjusting the overall transmittance and reflectivity, thereby adjusting the ratio of reflected light and refracted light formed by the light reaching the ordinary optical surface, and further controlling the intensity ratio of the illumination light and the monitoring light to obtain the desired intensity ratio.

[0031] Further, refer to Figure 1 As another case, in the right figure, one surface of the asymmetric beam splitter 10 is arranged toward the preset light source 40 to receive the preset light and reflect the monitoring light, and the other surface of the asymmetric beam splitter 10 is used to refract the illumination light.

[0032] It should be noted that, in this embodiment, Figure 3 Since there are certain differences in the internal structures (such as thickness) of the functional layer 12, the optical path of the light refracted by the ordinary optical surface and the special optical surface will be modulated to form decoherent illumination light and refracted to the exposure device 30, and the optical path of the light reflected by the ordinary optical surface and the special optical surface is consistent, modulated into monitoring light and reflected to the monitor 20.

[0033] Furthermore, in this embodiment, a dielectric layer 11 and a functional layer 12 are provided between two surfaces of the asymmetric beam splitter 10; The dielectric layer 11 is made of isotropic homogeneous material or anisotropic material; The functional layer 12 is made of metal material or optical medium material.

[0034] It is easy to understand that in this embodiment, combined with Figure 3, the dielectric layer 11 is close to one surface, and the functional layer 12 is close to the other surface. The dielectric layer 11 is made of an isotropic homogeneous material. An isotropic homogeneous material refers to a material whose physical, chemical and other properties will not differ due to different directions. The performance values ​​measured along different directions are exactly the same, such as homogeneous glass materials, fused quartz materials, etc.; it can also be an anisotropic material. An anisotropic material refers to a material whose all or part of the physical, chemical and other properties show certain differences depending on the direction. The performance values ​​measured in different directions are different, such as birefringent materials. The material of the functional layer 12 can be a metal material such as gold or titanium, or it can be other optical dielectric materials with optical properties. In a specific implementation, the transmission characteristics and reflection characteristics of the asymmetric beam splitter 10 can be designed by adjusting the relative position relationship between the dielectric layer 11 and the functional layer 12 and their respective thicknesses.

[0035] It is worth noting that, in this embodiment, combined with Figure 4 , Figure 4 It is an explanation of the refraction and reflection of light passing through the two surfaces of the asymmetric beam splitter, and is not limited to ordinary optical surfaces or special optical surfaces. In the specific light transmission path of the asymmetric beam splitter 10, the incident light I can form reflected light R12 and refracted light T12 after passing through one surface (the first and second numbers in the subscript represent the media on the incident side and the transmission side of the interface, respectively, for example, R12 represents the reflected light incident from medium A to medium B), the overall thickness of the asymmetric beam splitter 10 is d, the refracted light can be transmitted to the other surface through the asymmetric beam splitter 10, and form reflected light R23 and refracted light T23, respectively, and the reflected light can be transmitted back to one surface, and form reflected light R21 and refracted light T21, respectively. Furthermore, the reflected light R21 can also be further transmitted to another surface, and form reflected light and refracted light, respectively, which will not be elaborated here. Among them, the aforementioned reflected light R12 and refracted light T21 are light beams emitted from one surface to medium A, and the refracted light T23 is a light beam emitted from another surface to medium C.

[0036] Further, in this embodiment, the exposure device 30 includes: a mask work stage, a projection lens system, a wafer work stage and a calibration stage; The mask workpiece stage is used to carry the mask plate; The projection objective lens system is used to change the projection pattern of the received illumination light through the mask, and focus the illumination light to the wafer to be processed through the objective lens group; Wherein, the wafer worktable is used to carry the wafer to be processed; and the calibration table is used to calibrate the relative position between the mask and the wafer to be processed.

[0037] It should be noted that, in this embodiment, the exposure device 30 includes a mask worktable, a projection lens system, a wafer worktable, a calibration stage, etc. (not shown in the figure). Among them, the mask worktable is used to carry the mask plate, and the wafer worktable is used to carry the wafer to realize the functions of alignment, leveling and focusing, stepping and scanning exposure; the projection lens system is used to focus the pattern on the mask onto the surface of the wafer to be processed; the calibration stage is used to complete the alignment and correction of the mask plate and the wafer to be processed.

[0038] Furthermore, in this embodiment, the mask and the wafer worktable are arranged in any one of a contact type, a proximity type and a projection type.

[0039] It should be noted that, in this embodiment, the exposure device 30 can be configured in any exposure mode of proximity exposure, contact exposure and projection exposure. When the contact exposure mode and proximity exposure mode are adopted, the exposure device 30 may not include a projection objective lens system.

[0040] The embodiment of the present application provides a lithography illumination system, which includes: an asymmetric beam splitter, a monitor, an exposure device, a preset light source and a controller; the controller is electrically connected to the monitor and the preset light source respectively; the asymmetric beam splitter is arranged on the light output path of the preset light source, and is used to refract and reflect the preset light emitted by the preset light source, generate monitoring light and illumination light respectively on different light paths, and transmit the monitoring light to the monitor, and transmit the illumination light to the exposure device at the same time; the exposure device is used to perform exposure processing on the wafer to be processed based on the acquired illumination light; the monitor is used to monitor the light field distribution data of the monitoring light, and transmit the corresponding light field information to the controller; the controller is used to send a uniform light control signal to the preset light source based on the light field information; the preset light source is used to adjust the light source pixel parameters of the preset light based on the uniform light control signal. The preset light is divided into the monitoring light transmitted to the monitor and the illumination light transmitted to the exposure device by the asymmetric beam splitter, and the controller can obtain the light field distribution of the illumination light through the light field distribution of the monitoring light acquired by the monitor, so as to achieve the monitoring effect. At the same time, when the controller determines that the light field distribution of the illumination light is abnormal, it can adaptively adjust the light source pixel parameters corresponding to the preset light output by the preset light source, so that the generated illumination light continues to achieve the effect of uniform light. The above simple structure realizes the integration of uniform light and monitoring of the lithography illumination system, greatly reduces the hardware structure complexity of the entire lithography illumination system, and reduces the interference of the unstable light source to the lithography illumination system.

[0041] In addition, to achieve the above-mentioned purpose, the present application also proposes a lithography illumination method, which is applied to the lithography illumination system as described above. Figure 5 as well as Figure 6 As shown, the steps of the photolithography illumination method include steps S10-S20: Step S10, controlling a preset light source to emit preset light to the asymmetric beam splitter, and obtaining light field information corresponding to the monitoring light generated by the asymmetric beam splitter through a monitor, while enabling an exposure device to perform exposure through the illumination light generated by the asymmetric beam splitter; Step S20: Based on the light field information, control the preset light source to adjust the light source pixel parameters of the preset light, so as to adjust the illumination light.

[0042] It should be noted that, in this embodiment, the execution entity may be the controller mentioned above, and in the initial state, the controller controls the preset light source to emit preset light to the asymmetric beam splitter.

[0043] It is easy to understand that in this embodiment, after the preset light passes through the asymmetric beam splitter, a pair of monitoring light and illumination light can be generated respectively through transmission characteristics and reflection characteristics. The generated monitoring light can be transmitted to the monitor by changing the angle between the asymmetric beam splitter and the original light transmission path of the preset light, and the generated decoherent illumination light can be transmitted to the exposure device, so that the exposure device exposes the wafer to be processed through the received illumination light. The light field information corresponding to the light field distribution data of the received monitoring light can be obtained by the monitor, so as to confirm the light field distribution of the current monitoring light. Since the monitoring light and the illumination light are obtained by splitting the preset light of the same source, the light field distribution of the illumination light can also be determined by combining the light field distribution of the monitoring light with the modulation function designed by the asymmetric beam splitter. Subsequently, the light field distribution of the illumination light can be compared with the ideal light field distribution to confirm whether it meets the requirements of the current exposure device. If not, the preset light source can be controlled to adjust the light source pixel parameters of the output preset light, so as to adjust the light parameters (light field distribution) of the illumination light to the best, so that the exposure device works in the best state.

[0044] In addition, it should be noted that in this embodiment, the execution subject can use neural network deep learning to seek the corresponding relationship between the monitoring end and the exposure end. The core process of the neural network algorithm is as follows: first, data preparation is performed, including data cleaning, processing missing values ​​and outliers, and data standardization, which standardizes or normalizes the data to ensure that each feature is on the same scale; second, data segmentation is performed, and the data set is divided into a training set, a validation set, and a test set. The common ratio is 70% training set, 15% validation set, and 15% test set; then the neural network model is built, and the appropriate neural network architecture is selected, such as recurrent neural networks (RNN), convolutional neural networks (CNN), fully connected neural networks (FCNN), etc., and the neural network model is built using a deep learning framework, such as TensorFlow or PyTorch; the second is training the model, using the training data to train the model and verify it on the validation data; followed by evaluating the model, using the test data set to evaluate the model performance; then tuning and optimizing, according to the performance results of the model, hyperparameter tuning and model optimization can be performed, such as adjusting the number of network layers, the number of neurons in each layer, the learning rate, etc.; repeat the training model to the parameter optimization process until the model meets the application requirements, and finally use the model to predict, obtain the corresponding relationship between the light field distribution of the exposure end and the monitoring end, and generate a light source pixel parameter combination that can achieve the target uniform illumination light field pattern distribution, realize the monitoring uniform light integration function, and realize the pupil shaping function.

[0045] It is worth noting that, based on the consideration of uniform light, the controller can use intelligent algorithms to individually adjust the lighting combination of each pixel light source in the preset light source to achieve a specific lighting light field pattern distribution, thus realizing the pupil shaping function of the traditional lighting system. Figure 7 As shown, typical parameterized lighting form distributions include monopole, dipole, quadrupole, annular, ASML dipole, and ASML quadrupole lighting.

[0046] Further, in this embodiment, the step of controlling the preset light source to adjust the light source pixel parameters of the preset light based on the light field information to adjust the illumination light includes: Step S21, based on the light field information, obtaining light field distribution data of the current monitoring light; Step S22, acquiring the light field distribution data of the current illumination light based on the light field distribution data of the monitoring light; Step S23, when the light field distribution data of the illumination light does not conform to the preset light field data, output a corresponding light uniformity control signal to the preset light source, and adjust the light source pixel parameters of the preset light source to adjust the illumination light.

[0047] It should be noted that the preset light field data refers to the light field distribution data of the illumination light required to be received by the exposure device under an ideal state. In this embodiment, first, the light field information obtained by the monitoring light can be used to obtain the corresponding light field distribution data of the monitoring light. Based on the algorithm of the neural network model described above and the modulation function on the asymmetric spectrometer design, the relationship between the monitoring light and the illumination light can be inferred, and the light field distribution data of the illumination light can be obtained by combining the light field distribution data of the monitoring light. If the light field distribution data of the illumination light currently obtained does not meet the theoretical preset light field data, a corresponding uniform light control signal can be sent to the preset light source to adjust the light source pixel parameters corresponding to the preset light source, that is, to change the illumination combination of each pixel light source in the preset light source, thereby adjusting the light field uniformity (light field distribution) of the preset light, and then realizing adaptive adjustment of the light field distribution of the illumination light. In the above manner, the integration of uniform light and monitoring of the lithography illumination system can be realized, ensuring that the exposure device can always receive the illumination light with the best light parameters to expose the wafer to be processed. While reducing the complexity of the hardware structure of the entire lithography illumination system, the stability of the entire lithography illumination system can also be guaranteed.

[0048] In addition, to achieve the above purpose, the present application also proposes a lithography machine, which uses the lithography illumination system described above. Since the lithography machine uses all the embodiments of the lithography illumination system described above, it should also have the beneficial effects brought by the embodiments of the lithography illumination system described above, which will not be described one by one here.

[0049] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the present application.

Claims

1. A lithography illumination system, characterized in that: The photolithography illumination system comprises: an asymmetric beam splitter, a monitor, an exposure device, a preset light source and a controller; The controller is electrically connected to the monitor and the preset light source respectively; The asymmetric beam splitter is arranged on the light output path of the preset light source, and is used to refract and reflect the preset light emitted by the preset light source, generate monitoring light and illumination light on different light paths, and transmit the monitoring light to the monitor, and transmit the illumination light to the exposure device at the same time; The exposure device is used to perform exposure processing on the wafer to be processed based on the acquired illumination light; The monitor is used to monitor the light field distribution data of the monitoring light and transmit the corresponding light field information to the controller; The controller is used to send a uniform light control signal to the preset light source based on the light field information; The preset light source is used to adjust the light source pixel parameters of the preset light based on the uniform light control signal.

2. The lithography illumination system according to claim 1, characterized in that: One surface of the asymmetric beam splitter is disposed toward the preset light source and is used to receive the preset light and reflect the illumination light. The other surface of the asymmetric beam splitter is used to refract the monitoring light.

3. The lithography illumination system according to claim 1, wherein: One surface of the asymmetric beam splitter is arranged toward the preset light source, and is used to receive the preset light and reflect the monitoring light. The other surface of the asymmetric beam splitter is used to refract the illumination light.

4. The lithography illumination system according to claim 1, wherein: A dielectric layer and a functional layer are provided between the two surfaces of the asymmetric beam splitter; The dielectric layer is made of isotropic homogeneous material or anisotropic material; The functional layer is made of metal material or optical medium material.

5. The lithography illumination system according to claim 4, characterized in that: One surface of the asymmetric beam splitter is a smooth surface covered with an optical coating.

6. The lithography illumination system according to claim 1, wherein: The asymmetric beam splitter is further used to, when receiving the preset light, perform decoherence processing on the preset light to obtain the illumination light, and transmit the illumination light to the exposure device.

7. The lithography illumination system according to claim 1, wherein: The exposure device comprises: a mask workpiece stage, a projection lens system, a wafer workpiece stage and a calibration stage; The mask workpiece stage is used to carry the mask plate; The projection objective lens system is used to change the projection pattern of the received illumination light through the mask, and focus the illumination light to the wafer to be processed through the objective lens group; Wherein, the wafer worktable is used to carry the wafer to be processed; and the calibration table is used to calibrate the relative position between the mask and the wafer to be processed.

8. The lithography illumination system according to claim 7, wherein: The mask plate and the wafer worktable are arranged in any one of a contact type, a proximity type and a projection type.

9. A photolithography illumination method, characterized in that: Applied to the lithography illumination system according to any one of claims 1 to 8, the steps of the lithography illumination method include: Controlling a preset light source to emit preset light to the asymmetric beam splitter, and obtaining light field information corresponding to the monitoring light generated by the asymmetric beam splitter through a monitor, while causing an exposure device to perform exposure through the illumination light generated by the asymmetric beam splitter; Based on the light field information, the preset light source is controlled to adjust the light source pixel parameters of the preset light, so as to adjust the illumination light.

10. A photolithography machine, characterized in that: The lithography machine adopts the lithography illumination system as described in any one of claims 1-8.

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