Method and apparatus for scanning probe lithography

Abstract

The application discloses a kind of scanning probe lithography method and its device, belong to micro-nano processing technical field.The device of the present application includes probe array fixed on the carrier of surface shape adjustable, with the distance angle adjustable sample stage between carrier, feedback control system, power supply and motion control system, data processing and storage system etc.The method of the present application includes: respectively carrying out forward scanning and backward scanning at different spatial positions of sample, obtain the surface topography of sample by forward scanning, when backward scanning, according to the pattern to be processed and known topography, adjust the distance of probe and sample, control probe array to carry out pattern processing, and different size probe tip can be used to carry out different granularity pattern processing.By using the present application, large-area sample processing can be compatible, problems such as but not limited to total thickness variation and warping of wafer are overcome, the patterning speed of large-area sample is improved, and high-precision, high-alignment patterning process is realized.

Description

Technical Field

[0001] This invention belongs to the field of micro-nano fabrication technology for material surfaces, specifically relating to a patterning method and apparatus based on a scanning probe array. Background Technology

[0002] Scanning probe lithography (SPP) technology enables three-dimensional fabrication at the nanometer to sub-nanometer scale and is an indispensable tool in cutting-edge scientific and technological fields such as advanced materials, chip manufacturing, and biomedical engineering. In patent CN105793776B, the term "lithography" was used to translate "light lithography" in a context where it was not explicitly mentioned. In the following description, the term "patterning" is used instead of "light lithography" because this method does not actually involve optics. The scanning probe technology discussed here includes all techniques that use micro / nanostructured probes and operate in a scanning manner, including but not limited to scanning tunneling microscopy, atomic force microscopy, and dip-pen lithography. Reference 1 (K. Bian, C. Gerber, AJ Heinrich, et al. Scanning probe microscopy. Nature Reviews Methods Primers, (2021) 1:36) provides a comprehensive introduction to the types and principles of scanning probe technology.

[0003] Figure 1 This is a simplified schematic diagram of single-probe machining, mainly including the probe, the surface to be machined, the position driver, and a voltage-driven graphical mechanism. The probe includes a tip and a cantilever, where the probe cantilever is not mandatory; the graphical mechanism is also not necessarily voltage-driven. Figure 1This is provided for reference only to illustrate the technical principles of scanning probe fabrication. In the patterning process, a voltage-driven fabrication mechanism can create a potential difference between the probe tip and the surface to be processed. When the distance between them is sufficiently close, the probe tip emits electrons towards the surface. Upon arrival, these electrons can achieve localized material removal, modification, or deposition through physical or chemical processes. As the probe scans different areas of the surface, a specific pattern can be formed, i.e., patterning. The aforementioned electron emission mechanism requires the distance between the probe tip and the surface to be processed to be on the sub-micron scale; otherwise, electron emission is difficult to induce, thus limiting its applicability. Alternatively, a voltage-driven fabrication method can utilize the electrostatic force caused by the potential difference to bend the probe cantilever, allowing the probe tip to directly contact the surface. In this contact state, the relative movement between the probe and the sample achieves patterning through physical scribing.

[0004] Based on the aforementioned scanning probe processing principle, patent publication number WO2015036605A1 disclosed a more complex nanopatterning system on March 19, 2015. This system includes an active distance sensing unit. By reciprocating along the same line segment, a closed loop of processing and measurement can be formed to monitor in real time whether the processed morphology matches the design. This process involves real-time, precise, feedback-based distance control between the probe and the surface to be processed. This distance control is achieved by adjusting the overall position of the probe using a piezo stage. While this solution can achieve high-precision three-dimensional processing, the piezo stage itself is much larger than the probe, limiting the system's total bandwidth due to its mechanical response speed and hindering high-density integration of multiple probes. To achieve faster single-probe processing speeds and high-density integration of multiple probes, an integrated solution is needed to replace the piezo stage. Furthermore, the technical solution disclosed in this patent uses pixel-by-pixel processing, which is beneficial for reducing probe wear and increasing energy efficiency, but it is not conducive to processing low-roughness line patterns. Line patterns with extremely low edge roughness (<1nm) are a very critical processing target in semiconductor chip manufacturing. The patent also discloses a mechanism for driving the cantilever by forming a potential difference between the sample and the probe; however, reference 2 (Colin D. Rawlings, Michal Zientek, Martin Spieser, et al. Control of the interaction strength of photonic molecules by nanometerprecise 3D fabrication, Scientific Reports, 7(1). (2017)) reports that the crosstalk problem caused by this mechanism will affect the resolution of high-precision processing.

[0005] The aforementioned single-probe pixel-by-pixel processing techniques are difficult to achieve high-throughput, large-area patterning. Reference 3 (Pozidis H, Haberle W, Wiesmann DW, et al. Demonstration of Thermomechanical Recording at 641 Gbit / in2[J]. IEEE Transactions on Magnetics, 2004, 40(4): 2531-2536) introduces a technique for high-density integration and parallel operation of thousands of probes. In this technique, probes are integrated on a carrier plane, and each probe cantilever can be driven individually to make the probe tip contact the surface to be processed (a polymer), and form a concave morphology on the polymer surface by heating. Although this technique can achieve high-density integrated multi-probe parallel processing, it only controls the distance between the carrier plane and the sample, and the distance between each probe and the surface to be processed is not individually controlled, thus limiting the processing accuracy. Furthermore, this technical solution involves a relatively small total area of ​​the surface to be processed, making planarization relatively easy. However, it does not consider the potential warping of the surface, thus limiting its application to large areas, such as large-area wafers with thickness inhomogeneity and warping. For instance, the cantilever in this solution has a limited driving distance, typically within 1 micrometer. For samples with uneven thickness, if the surface thickness difference exceeds 1 micrometer, the probe may not be able to contact the surface in some areas, preventing processing. Summary of the Invention

[0006] In view of the problems existing in the prior art, the present invention discloses a method and apparatus for patterning scanning probes, which utilizes an integrated probe array to perform parallel patterning of multiple probes, thereby realizing large-scale probe integration and high-throughput, nanometer-level precision large-area pattern processing.

[0007] The scanning probe patterning device disclosed in this invention mainly comprises:

[0008] A probe array fixed on a carrier, each array containing no fewer than two probes with independent measurement and control functions; a distance sensing unit and a cantilever driving unit are integrated on the probe cantilever; the distance sensing unit generates a signal quantity related to the distance between the probe tip and the sample; the cantilever driving unit drives the cantilever to move, thereby adjusting the distance between the probe tip and the sample; one or more probe tip sizes are selected in the probe array, and different sized probe tips are used to process patterns of different particle sizes;

[0009] The carrier has an adjustable surface shape and includes: a plane A that provides mechanical support for clamping the carrier, a plane B that fixes the probe array and has an adjustable surface shape, and a telescopic mechanism disposed between plane A and plane B; wherein the surface shape of plane B changes with the extension and retraction of the telescopic mechanism.

[0010] The sample stage includes a piezoelectric scanning stage and a displacement device. The sample is fixed on the piezoelectric scanning stage. The horizontal displacement of the sample is adjusted by the piezoelectric scanning stage, and the vertical displacement and angle between the sample and the carrier are adjusted by the displacement device. During the pattern writing process, the potential difference between the sample and the probe is maintained at zero.

[0011] The feedback control system reads the distance-related signal output from each probe, calculates the control signal to drive the cantilever motion and outputs it to the cantilever drive unit, and calculates the control signal to control the telescopic mechanism and displacement device motion and outputs it to the power supply and motion control system.

[0012] Power supply and motion control system, used for power supply and control of the movement of telescopic mechanism and displacement device;

[0013] The data processing and storage system saves the control signals output by the feedback control system that drive the cantilever motion over time, as well as the changes in the sample's spatial position over time.

[0014] A reference clock is used to provide a uniform time scale reference.

[0015] The distance sensing unit uses thermal, electrical, or acoustic methods to measure the distance between the probe and the surface being detected.

[0016] The probe tips are used to process the sample in a contact or non-contact manner. The feedback control system superimposes a modification signal on the calculated control signal that drives the cantilever motion and outputs it to the cantilever drive unit to control the distance between each probe tip and the sample during the pattern writing stage. The active probe tips are powered by a power supply and motion control system, which also controls their opening and closing.

[0017] Based on the above-described apparatus, the method for patterning a scanning probe implemented by the present invention includes the following steps:

[0018] (1) Adjust the distance between the carrier and the sample stage, as well as the surface shape of the carrier, so that the maximum distance between each probe in the probe array and the sample surface does not exceed the maximum movement distance that the cantilever drive unit can achieve;

[0019] The adjustment of the carrier surface shape includes: if the macroscopic morphological characteristics of the sample are known, initially, the power supply and motion control system drives the telescopic mechanism to move according to the morphological characteristics, and performs open-loop carrier surface shape adjustment; if the morphological characteristics of the sample are unknown, the distance sensing unit of each probe outputs a signal quantity related to the distance between the probe tip and the sample, and the power supply and motion control system drives the displacement device and the telescopic mechanism so that the signal quantity output by each probe is close to the same value.

[0020] (2) During the forward scanning process, the distance sensing unit integrated on each probe obtains the signal quantity related to the distance between the probe tip and the sample, and transmits it to the feedback control system in real time. The feedback control system calculates and outputs control signals to the cantilever drive unit and the power and motion control system. The cantilever drive unit adjusts the position of the cantilever according to the received control signals so that the signal quantity output by the distance sensing unit of each probe is maintained at the set value. The change of the control signal of the cantilever drive unit of each probe with time during the forward scanning process is recorded. Combined with the change of the sample spatial position with time during the scanning motion, the morphological changes of the sample surface on the scanning path of each probe are calculated.

[0021] (3) During the backward scanning process, each probe moves in the opposite direction along the same curve as the forward scanning. During the movement, the probe position is adjusted according to the cantilever control signal recorded during the forward scanning to ensure that the distance between the probe and the sample is known during the backward scanning process. According to the pattern to be processed, each probe starts the pattern writing operation at the corresponding time and ends the pattern writing operation at the corresponding time. During the backward scanning process, in order to reduce the error caused by the potential difference, the probe and the sample are kept at zero potential difference. However, if the processing accuracy error caused by the potential difference can be ignored for a specific processing task, it is possible to choose not to maintain zero potential difference.

[0022] (4) Based on the graphic to be processed and the known probe position, calculate the scanning path required to achieve the whole graphicization; adjust the relative position of the sample and the probe array by means of displacement and telescopic mechanism, perform forward and backward scanning at different spatial positions to process the graphic, and finally obtain the overall graphic; in the graphic processing, use probe tips of different sizes to process patterns of different granularities.

[0023] Compared with the prior art, the advantages and positive effects of the present invention are as follows: (1) The device and method of the present invention use a carrier with adjustable surface shape to be compatible with the processing of large-area samples, which can overcome, for example, but not limited to, the problem of total thickness variation and warping of wafers; (2) The device and method of the present invention use a probe array with different probe tip sizes to improve the patterning speed. For example, a relatively large-sized probe tip can be used for coarse-grained patterning, and a relatively small-sized probe tip can be used to complete fine-grained patterning, thereby improving the patterning processing efficiency; (3) The device and method of the present invention achieves high-precision and high-alignment patterning process through forward scanning detection and backward scanning return patterning; (4) The device and method of the present invention can eliminate crosstalk noise caused by maintaining zero potential difference between the sample and the probe during the patterning process, thereby improving the accuracy of patterning processing. Attached Figure Description

[0024] Figure 1 This is a simplified schematic diagram of a single-probe scanning machining system;

[0025] Figure 2 This is a schematic diagram of the scanning probe patterning device for multi-probe parallel operation of the present invention;

[0026] Figure 3 This is a schematic diagram illustrating a possible implementation of the adjustable surface vehicle of the present invention;

[0027] Figure 4 This is a schematic diagram of a possible cantilever driving method under the condition of maintaining zero potential difference between the sample and the cantilever according to the present invention.

[0028] Figure 5 This is a schematic diagram of the drive circuit and signal processing circuit of the multi-probe scanning processing device of the present invention.

[0029] In the picture:

[0030] 1-Cantilever; 2-A-size probe tip; 3-B-size probe tip; 4-Distance sensing unit; 5-Cantilever drive unit;

[0031] 6-Carrier; 7-Sample; 8-Piezoelectric scanning stage; 9-Displacement device A; 10-High-stiffness plane; 11-Low-stiffness material layer;

[0032] 12-Telescopic mechanism; 13-Displacement device B; 14-Feedback control system; 15-Power supply and motion control system;

[0033] 16-Data processing and storage system; 17-Reference clock. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0035] This invention provides a method and apparatus for scanning probe patterning to achieve high-throughput, large-area, and nanometer-level precision material surface patterning. High-throughput targets can be achieved by multiple probes in parallel, while high-precision targets require morphology detection of the sample before processing. Compatibility with large-area samples can be achieved by a probe array carrier with adjustable surface shape.

[0036] like Figure 2 As shown, the main structure of the scanning probe patterning device of the present invention includes: a probe array, wherein each probe consists of a probe tip 2,3 integrated on a cantilever 1, a distance sensing unit 4, and a cantilever driving unit 5; the probe array is fixed on a carrier 6; a sample stage that can move in at least four spatial degrees of freedom for fixing a sample 7; the sample stage includes a piezoelectric scanning stage 8 and a displacement device A9, and the sample 7 is fixed on the piezoelectric scanning stage 8; a three-dimensional coordinate system is established, wherein the xy plane is parallel to the plane of the piezoelectric scanning stage 8, and the positive z-axis is perpendicular to the xy plane and pointing upwards; the piezoelectric scanning stage 8 is used to adjust the movement of the sample 7 in the xy plane, and the displacement device A9 is located below the piezoelectric scanning stage 8 to adjust the height and tilt angle of the sample 7.

[0037] For clarity of illustration, the embodiments of the present invention are shown below. Figure 2 The probe array consists of four probes arranged collinearly. However, in the implementation of this invention, each probe array can be non-collinearly arranged, but when the carrier surface is a plane, they should be arranged as coplanarly as possible to reduce systematic errors. In the case of non-collinear arrangement, the relative position of the sample stage and the probe carrier 6 needs to be adjusted in at least five spatial degrees of freedom. This can be achieved by a piezoelectric scanning stage 8 in the xy plane plus three z-axis displacements A9, or by a piezoelectric scanning stage 8 in the xy plane plus one z-axis displacement and two tilting stages. Similarly, Figure 2 The two z-axis displacement devices A9 that control the four spatial degrees of freedom can also be replaced by a single z-axis displacement device and a tilting table. Figure 2 The displacement device A9 is used to adjust the spatial position of the sample.

[0038] Figure 2 Only four probes are shown in the diagram to represent a multi-probe array. In the implementation of this invention, the probe array can be a single array or multiple arrays. The number of probes in each array is determined by the area of ​​the carrier and the size of a single probe. Each array includes at least two probes with independent measurement and control functions, but there is no fixed limit to the total number of probes. For example, when applied to pattern processing of large-area samples, a total of tens of thousands of probes can be set to speed up image processing.

[0039] Figure 2Different numbers are used to identify probe tips of different sizes, such as probe tip 2 of size A and probe tip 3 of size B. The numbers 2 and 3 indicate probe tips of different sizes. In the implementation of the present invention, there may be more than two sizes of different tips, but the position of each probe and its tip size are known and not random.

[0040] This invention employs a probe carrier 6 with an adjustable surface shape. An embodiment of this invention provides an implementation method, such as... Figure 3 As shown, it includes: a high-stiffness plane 10, a low-stiffness material layer 11, a telescopic mechanism 12, and a displacement device B13; wherein, the high-stiffness plane 10 serves as a reference plane for the carrier 6 and provides mechanical support for the clamping of the carrier 6; the low-stiffness material layer 11 is used to fix the probe array; multiple telescopic mechanisms 12 are fixed between the high-stiffness plane 10 and the low-stiffness material layer 11, and the surface shape of the low-stiffness material layer 11 is adjusted by controlling the displacement of the telescopic mechanisms 12; the displacement device B13 is used to adjust the position of the probe carrier 6 to realize the overall movement of the carrier 6, but the displacement device B13 may not be provided depending on the actual situation. Figure 3 The system includes four telescopic mechanisms 12, but in the implementation of this invention, there is no upper limit to the number of telescopic mechanisms 12, but it shall not be less than one. After the high-rigidity plane 10 is fixed, as the length of the telescopic mechanism 12 changes, the surface shape of the low-rigidity material layer 11 will change. The side of the low-rigidity material layer 11 that fixes the probe array may not be a plane, that is, the surface shape of the probe carrier 6 is adjustable, thereby causing the position of the probes fixed on the low-rigidity material layer 11 to move. In this embodiment of the invention, the materials used to implement the high-rigidity plane 10 and the low-rigidity material layer 11 are not limited, as long as they meet the requirements. The high-rigidity plane 10 serves as a reference plane, with a fixed surface shape and a robust material, such as aluminum oxide. The low-rigidity material layer 11 can be implemented using, but is not limited to, polymers, and its surface shape can change with the displacement of the telescopic mechanism 12.

[0041] Figure 2 The positions of the mid-range sensing unit 4 and the cantilever driving unit 5 relative to the cantilever 1 are for reference only, and there are no strict limitations on their specific positions in the implementation of this invention. The distance sensing unit 4 and the probe tips 2 and 3 can be the same entity. For example, when the distance-related signal is current, the probe tips 2 and 3 emit electrons towards the surface of the sample 7, and the probe tips 2 and 3 then function as the distance sensing unit 4, providing a signal related to the distance between the probe and the sample surface. Figure 2 The cantilever drive unit 5 shown can be, but is not limited to, a piezoelectric actuator, an electrothermal actuator, or an electrostatic actuator integrated on the cantilever, and can be selected according to different needs.

[0042] Regarding distance measurement, the distance sensing unit 4 can be, but is not limited to, based on thermal, electrical, or acoustic methods. For example, when there is a temperature difference between the probe and the surface being tested, a temperature-sensitive resistor can be integrated on the probe to react to distance changes, as described in Reference 4 (Williams CC, Wickramasinghe H K. Scanning thermal profiler[J]. Applied Physics Letters, 1986). In this case, the distance sensing unit 4 of the present invention measures the resistance value and sends it to the feedback control system 14 as a distance-related signal. When there is a potential difference between the probe and the surface being tested, the probe tip can emit electrons towards the surface being tested, and the current magnitude is related to the distance, as described in Reference 5 (Behzadirad M, Mecholdt S, Randall JN, et al. Advanced Scanning Probe Nanolithography Using GaN Nanowires[J]. Nano letters, 2021(13):21). In this case, the distance sensing unit 4 of the present invention and the probe tip are the same entity, and the measured current magnitude is sent to the feedback control system 14 as a distance-related signal.

[0043] Regarding the implementation mechanism of the cantilever drive unit 5, microelectromechanical actuators based on piezoelectric, thermal stress, electrostatic force and other methods can achieve stable and repeatable nanometer-level or even picometer-level motion control. However, it should be noted that during the pattern writing process, the potential difference between the sample and the probe should be kept at zero to avoid possible crosstalk problems.

[0044] The present invention provides possible cantilever driving methods under the condition of maintaining zero potential difference between sample 7 and cantilever 1, such as... Figure 4 As shown: Figure 4 In the left part, the cantilever drive unit 5 can be a material layer that generates stress through electrothermal activity or a material layer that generates stress through piezoelectric activity. The aforementioned stress can drive the cantilever 1 to bend, thereby achieving the goal of adjusting the distance between the probe tips 2 and 3 and the sample 7. Figure 4 In the right section, the cantilever drive unit 5 consists of a pair of electrodes integrated onto the cantilever 1 and the carrier 6, respectively. By creating a potential difference between the electrodes, the distance between the probe tips 2 and 3 and the sample 7 can be adjusted by electrostatic force. Figure 4 In the two embodiments given, the sample 7 and the probe maintain a zero potential difference by short-circuiting and sharing a common ground. In the implementation of this invention, it is also possible to maintain a zero potential difference by either short-circuiting or sharing a common ground. If the machining accuracy error caused by the potential difference is negligible for a specific machining task, it is also possible to choose not to maintain a zero potential difference.

[0045] The drive circuit and signal processing circuit of the multi-probe scanning processing device of the present invention, such as Figure 5 As shown, it mainly includes: a distance sensing unit 4, a cantilever drive unit 5, a piezoelectric scanning stage 8 and a displacement device A9 for the sample stage, a carrier displacement device B13, a feedback control system 14, a power supply and motion control system 15, a data processing and storage system 16, and a reference clock 17. If the probe tips 2 and 3 are active, they require power supply; if they are passive, they do not require power supply. Figure 5 The circuits are connected in the system. The feedback control system 14 reads the signal quantity output by each probe related to the distance between the probe tip and the sample, calculates and outputs control signals to control the cantilever drive unit 5, and calculates and outputs control signals to control the movement of the telescopic mechanism 12 and displacement devices A9 and B13 to the power supply and motion control system 15. The power supply and motion control system 15 mainly provides energy to the components in the device, and also controls the movement of each telescopic mechanism 12 of the carrier 6, and controls the movement of displacement devices A9 and B13. The data processing and storage system 16 stores the time-varying control signals output by the feedback control system 14 to the cantilever drive unit 5, as well as the changes in the sample's spatial position over time, and calculates the morphological changes of the sample surface along the scanning path of each probe. The reference clock 17 provides a unified time reference for all active components in the overall device, such as the feedback control system 14, the power supply and motion control system 15, and the data processing and storage system 16.

[0046] based on Figures 2 to 5 The described apparatus and the method for measuring, controlling, and graphically representing the probe array of the present invention include:

[0047] Step 1: First, adjust the surface shape of the carrier 6 according to the morphological characteristics of sample 7. Then, adjust the distance between the plane of the carrier 6 and the sample stage using the piezoelectric scanning stage 8, displacement device A9, and displacement device B13. This ensures that the maximum distance between each probe 2,3 in the probe array and the surface of sample 7 does not exceed the maximum movement distance achievable by the cantilever drive unit 5 during the initial state and processing. When adjusting the surface shape of the carrier 6, calculate the required adjustment length of each telescopic mechanism 12 to ensure that the distance between each probe tip and the sample in the fixed probe array on the carrier 6 does not exceed the displacement range that the cantilever can drive.

[0048] During the adjustment process, if the macroscopic morphological features of sample 7 are known, the piezoelectric scanning stage 8, displacement device A9, displacement device B13, and telescopic mechanism 12 can be adjusted under the drive of the power supply and motion control system 15 to achieve open-loop 6-face shape adjustment of the carrier. If the macroscopic morphological features of sample 7 are unknown, the distance sensing unit 4 on the probe cantilever can be used to detect the distance between each probe and the sample in real time. By adjusting displacement device A9, displacement device B13, and telescopic mechanism 12, the signal output of each probe can be made close to the same value to achieve closed-loop 6-face shape adjustment of the carrier.

[0049] Step 2: During the forward scanning process, the distance-related signal quantity from the probe tip to the sample surface is obtained through the distance sensing unit 4 integrated on each probe. As the relative position between the sample 7 and the carrier 6 changes during the forward scanning process, the distance-related signal quantity may change due to the non-uniformity of the sample surface morphology. During the forward scanning process, the distance-related signal quantity measured by each probe is transmitted to the feedback control system 14 in real time, which then controls the signal quantity S output by each probe. i The processing sends control signals C to the cantilever drive unit 5 integrated on each probe cantilever. i ,i is the probe label, which takes a positive integer value, and the control signal C i The position of the cantilever 1 of probe i can be adjusted so that the signal output by the distance sensing unit 4 is maintained at a set value. This can be done by maintaining the same set value for each distance sensing unit 4, or by maintaining different set values ​​for each unit. By recording the changes in the control signals received by each probe cantilever 1 over time during the forward scanning process, and combining this with the changes in the spatial position of the sample 7 over time during the scanning motion, the morphological changes of the sample surface along the scanning path of each probe can be calculated by the data processing and storage system 16.

[0050] Step 3: During the backward scan, each probe moves in the opposite direction along the same curve as the forward scan. During this movement, the cantilever control signal C recorded during the forward scan is used as the reference. iThe probe positions are adjusted to ensure that the microscopic distance between the probe and the sample is known during the backward scanning process. Based on the pattern to be processed, each probe tip 2,3 initiates and terminates the writing operation at appropriate time points. The start and end times of the writing operation for each probe tip are set according to the pattern to be processed. During the backward scanning process, to reduce errors caused by potential difference, a zero potential difference should be maintained between the probe and the sample. If the processing accuracy error caused by potential difference is negligible for a specific processing task, maintaining a zero potential difference can be chosen. The processing of the sample by the probe tips 2,3 can be contact-based, such as mechanical scribing or thermal processing, or non-contact-based, such as dip pen direct writing or near-field optical processing. In the implementation of this invention, the feedback control system 14 can also control the cantilever via the cantilever control signal C. i Based on the superimposed modification signal M i This controls the distance between each probe tip and the sample during the pattern writing stage. The active probe tips can be powered and controlled by a power supply and motion control system 15.

[0051] Step 4: Based on the graphic design and the known probe positions, calculate the scanning path required to achieve the entire patterning. Adjust the relative position of the sample and the probe array using a displacement device, and perform forward and backward scans at different spatial positions to obtain the overall graphic. For example, in Step 2, the sample morphology is read through forward scanning, and in Step 3, patterning is performed through backward scanning. If the probe array contains probes with different tip sizes, different granularity patterns can be processed using probe tips of different sizes. Relatively large tips can be used for coarse-grained patterning, and relatively small tips can be used for fine-grained patterning to improve processing efficiency. In the implementation of this invention, there can be more than two sizes of different tips, but the position and tip size of each probe are known and not random.

[0052] Except for the technical features described in the specification, all other technologies are known to those skilled in the art. Descriptions of well-known components and technologies are omitted in this invention to avoid redundancy and unnecessary limitation. The embodiments described above do not represent all embodiments consistent with this application. Various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this invention are still within the protection scope of this invention.

Claims

1. A scanning probe photolithography apparatus, characterized in that, The device includes: A probe array fixed on a carrier, each array containing no fewer than two probes with independent measurement and control functions; a distance sensing unit and a cantilever driving unit are integrated on the probe cantilever; the distance sensing unit generates a signal quantity related to the distance between the probe tip and the sample; the cantilever driving unit drives the cantilever to move, thereby adjusting the distance between the probe tip and the sample; one or more probe tip sizes are selected in the probe array, and different sized probe tips are used to process patterns of different particle sizes; The carrier has an adjustable surface shape and includes: a plane A that provides mechanical support for clamping the carrier, a plane B that fixes the probe array and has an adjustable surface shape, and a telescopic mechanism disposed between plane A and plane B; wherein the surface shape of plane B changes with the extension and retraction of the telescopic mechanism. The sample stage includes a piezoelectric scanning stage and a displacement device. The sample is fixed on the piezoelectric scanning stage. The horizontal displacement of the sample is adjusted by the piezoelectric scanning stage, and the vertical displacement and angle between the sample and the carrier are adjusted by the displacement device. The feedback control system reads the distance-related signal output from each probe, calculates the control signal to drive the cantilever motion and outputs it to the cantilever drive unit, and calculates the control signal to control the telescopic mechanism and displacement device motion and outputs it to the power supply and motion control system. A power supply and motion control system is used to supply power and control the movement of the telescopic mechanism and displacement device. When the macroscopic morphological characteristics of the sample are initially obtained, the power supply and motion control system controls the movement of the sample stage and adjusts the surface shape of the carrier so that the maximum distance between each probe in the probe array and the sample surface does not exceed the maximum movement distance achievable by the cantilever drive unit. When the morphological characteristics of the sample are initially unknown, the distance sensing unit of each probe outputs a signal quantity related to the distance between the probe tip and the sample in real time. By adjusting the displacement device and the telescopic mechanism, the signal quantity output by each probe is made to approach a similar value. The data processing and storage system saves the time-varying control signals output by the feedback control system to the cantilever drive unit, as well as the time-varying spatial position of the sample, and calculates the morphological changes of the sample surface along the scanning path of each probe. A reference clock is used to provide a uniform time scale reference. In the device, a short circuit and / or common ground are set between the sample and the probe to maintain zero potential difference between the sample and the probe.

2. The apparatus according to claim 1, characterized in that, The probe tips are used to process the sample in a contact or non-contact manner. The feedback control system superimposes a modification signal on the control signal that drives the cantilever motion and outputs it to the cantilever drive unit to control the distance between each probe tip and the sample during the pattern writing stage. The active probe tips are powered by a power supply and motion control system, which also controls their opening and closing.

3. The apparatus according to claim 1, characterized in that, The distance sensing unit uses thermal, electrical, or acoustic methods to measure the distance between the probe and the surface being detected.

4. The apparatus according to claim 1, characterized in that, The vehicle is also equipped with a displacement device on plane A for adjusting the position of the vehicle.

5. The apparatus according to claim 1, characterized in that, The cantilever drive unit is a material layer that generates stress through electrothermal activity or a material layer that generates stress through piezoelectric activity. The stress generated drives the cantilever to bend, adjusting the distance between the probe tip and the sample.

6. The apparatus according to claim 1, characterized in that, The cantilever drive unit consists of a pair of electrodes, which are integrated on the cantilever and the carrier, respectively. By forming a potential difference between the electrodes, the distance between the probe and the sample is adjusted by electrostatic force.

7. A scanning probe patterning method based on the scanning probe lithography apparatus according to claim 1, 2, or 3, characterized in that, Includes the following steps: Step 1: Adjust the distance between the carrier and the sample stage, as well as the surface shape of the carrier, through the displacement device and the telescopic mechanism, so that the maximum distance between each probe in the probe array and the sample surface does not exceed the maximum movement distance that the cantilever drive unit can achieve. The adjustment of the carrier surface shape includes: if the macroscopic morphological characteristics of the sample are known, initially, the power supply and motion control system drives the telescopic mechanism to move according to the morphological characteristics, and performs open-loop carrier surface shape adjustment; if the morphological characteristics of the sample are unknown, the distance sensing unit of each probe outputs a signal quantity related to the distance between the probe tip and the sample, and the power supply and motion control system drives the displacement device and the telescopic mechanism so that the signal quantity output by each probe is close to the same value. Step 2: During the forward scanning process, the distance sensing unit of each probe obtains the signal quantity related to the distance between the probe tip and the sample, and transmits it to the feedback control system in real time. The feedback control system calculates and outputs control signals to the cantilever drive unit and the power and motion control system. The cantilever drive unit adjusts the position of the cantilever according to the received control signals, so that the signal quantity output by the distance sensing unit of each probe is maintained at the set value. The changes of the control signals of the cantilever drive units of each probe over time and the changes of the sample spatial position over time are recorded during the forward scanning process, and the morphological changes of the sample surface along the scanning path of each probe are calculated. Step 3: During the backward scanning process, each probe moves in the opposite direction along the same curve as the forward scanning. During the movement, the probe position is adjusted according to the control signal of the cantilever drive unit recorded during the forward scanning to ensure that the distance between the probe tip and the sample is known during the backward scanning process. According to the pattern to be processed, each probe starts the pattern writing operation at the corresponding time and ends the pattern writing operation at the corresponding time. During the backward scanning process, the potential difference between the sample and the probe is maintained at zero potential difference. Step 4: Calculate the scanning path required to achieve the entire patterning based on the pattern to be processed and the known probe positions; adjust the relative positions of the sample and the probe array, and perform forward and backward scans at different spatial positions of the sample to process the pattern; in the pattern processing, use probe tips of different sizes to process patterns of different granularities.

Images