Nanoscale Thin Film Deposition System

Abstract

A method and system for plannable contouring of a substrate with nanoscale precision is disclosed. A contouring material is dispensed onto a substrate or superstrate. The superstrate is brought into contact with the substrate. After contacting the superstrate with the substrate, the contouring material is then cured. The superstrate is separated from the substrate after curing. An optical measurement of a point on the substrate corresponding to the final substrate contour is then performed.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 981,182, entitled "Nanoscale Precision Programmable Profiling: Apparatus and Process," filed February 25, 2020, which is incorporated by reference herein in its entirety.

[0002] The present invention relates generally to nanoscale thin film deposition, and more particularly to programmable contouring with nanoscale precision. [Background technology]

[0003] In the electronic device field, roll-to-roll processing, also known as web processing, reel-to-reel processing, or R2R, is the process of creating electronic devices on a roll of flexible plastic or metal foil. In other fields that predate this use, roll-to-roll processing can refer to any process that begins with a roll of flexible material and then rewinds it to create an output roll. These processes, and others such as sheeting, can be grouped together under the general term conversion. Once the roll of material is coated, laminated, or printed, it can subsequently be slit to finished size in a slitter-rewinder. Summary of the Invention [Problem to be solved by the invention]

[0004] Although roll-to-roll machining is an inexpensive process, it has not been applicable to precise nanoscale surface contouring.

[0005] Furthermore, current techniques for realizing optoelectronic devices such as metal mesh transparent conductive electrodes, wire grid polarizers, and light trapping gratings are limited to rigid substrates, lack the necessary patterning resolution, and involve inefficient metal lift-off / etching processes and / or transfer steps. [Means for solving the problem]

[0006] In one embodiment of the present invention, a system for plannable contouring with nanoscale precision includes a contouring module having an inkjet for dispensing a contouring material. The system further includes a subsystem for handling a roll-based superstrate, the superstrate being used to form a continuous film of the contouring material between the superstrate and the substrate. The system additionally includes a subsystem for curing the contouring material. Furthermore, the system includes a metrology module.

[0007] In another embodiment of the present invention, a method for programmable contouring with nanoscale precision in a substrate includes dispensing a contouring material onto a first portion of the substrate or a first portion of a superstrate. The method further includes contacting a second portion of the superstrate with the second portion of the substrate. The method additionally includes sandwiching the contouring material between a third portion of the superstrate and the third portion of the substrate. The method further includes curing the contouring material. The method also includes separating the superstrate from the substrate after curing.

[0008] The foregoing has outlined rather broadly the features and technical advantages of one or more embodiments of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which may form the subject of the claims of the invention.

[0009] A better understanding of the present invention can be obtained when the following detailed description is considered in conjunction with the following drawings. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram of an nP3 device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram of a contouring subsystem of the nP3 device, in accordance with an embodiment of the present invention. [Figure 3] FIG. 2 is a schematic diagram of a contouring subsystem having an alternative web handling system according to an embodiment of the present invention. [Figure 4] FIG. 2 illustrates the structure of a lateral register mechanism according to an embodiment of the present invention. [Figure 5] FIG. 1 illustrates a superstrate tension control system according to an embodiment of the present invention. [Figure 6A] FIG. 10 illustrates a system for precision alignment of an idler wheel in a contouring zone in accordance with an embodiment of the present invention. [Figure 6B] FIG. 10 illustrates a system for precision alignment of an idler wheel in a contouring zone in accordance with an embodiment of the present invention. [Figure 7A] FIG. 1 illustrates a UV-transparent vacuum chuck with gap measurement sensors according to an embodiment of the present invention. [Figure 7B] FIG. 1 illustrates a UV-transparent vacuum chuck with gap measurement sensors according to an embodiment of the present invention. [Figure 7C1] FIG. 1 illustrates a UV-transparent vacuum chuck with gap measurement sensors according to an embodiment of the present invention. [Figure 7C2] FIG. 1 illustrates a UV-transparent vacuum chuck with gap measurement sensors according to an embodiment of the present invention. [Figure 7C3] FIG. 1 illustrates a UV-transparent vacuum chuck with gap measurement sensors according to an embodiment of the present invention. [Figure 8A] FIG. 1 illustrates a voice coil motor driven flexible support stage for vertical-tip-tilt motion according to an embodiment of the present invention. [Figure 8B]FIG. 1 illustrates a voice coil motor driven flexible support stage for vertical-tip-tilt motion according to an embodiment of the present invention. [Figure 8C] FIG. 1 illustrates a voice coil motor driven flexible support stage for vertical-tip-tilt motion according to an embodiment of the present invention. [Figure 9A] FIG. 1 illustrates a substrate chuck having a transmissive central region for optical metrology, according to an embodiment of the present invention. [Figure 9A1] FIG. 1 illustrates a substrate chuck having a transmissive central region for optical metrology, according to an embodiment of the present invention. [Figure 9B] FIG. 1 illustrates a substrate chuck having a transmissive central region for optical metrology, according to an embodiment of the present invention. [Figure 9C] FIG. 1 illustrates a substrate chuck having a transmissive central region for optical metrology, according to an embodiment of the present invention. [Figure 10A] 10A-10C illustrate alignment mechanisms for parallelism between a superstrate and a substrate according to an embodiment of the present invention. [Figure 10B] 10A-10C illustrate alignment mechanisms for parallelism between a superstrate and a substrate according to an embodiment of the present invention. [Figure 11A] 1 illustrates an inkjet assembly and fixture for large width inkjet according to an embodiment of the present invention. [Figure 11B] 1 illustrates an inkjet assembly and fixture for large width inkjet according to an embodiment of the present invention. [Figure 11C] 1 illustrates an inkjet assembly and fixture for large width inkjet according to an embodiment of the present invention. [Figure 12A] FIG. 2 illustrates the structure of an nP3 metrology subsystem according to an embodiment of the present invention. [Figure 12B] FIG. 2 illustrates the structure of an nP3 metrology subsystem according to an embodiment of the present invention. [Figure 13A] FIG. 1 illustrates a laser beam alignment module in an nP3 optical metrology module, according to an embodiment of the present invention. [Figure 13B] FIG. 1 illustrates a laser beam alignment module in an nP3 optical metrology module, according to an embodiment of the present invention. [Figure 14A] FIG. 1 illustrates an automatic telescoping system in a metrology module, according to an embodiment of the present invention. [Figure 14B] FIG. 1 illustrates an automatic telescoping system in a metrology module, according to an embodiment of the present invention. [Figure 15] 1 is a flow diagram of a method for performing optical metrology at all points on a substrate, according to an embodiment of the present invention. [Figure 16A] 16A-16C are cross-sectional views of performing optical metrology at all points on a substrate using the steps set forth in FIG. 15 according to an embodiment of the present invention. [Figure 16B] 16A-16C are cross-sectional views of performing optical metrology at all points on a substrate using the steps set forth in FIG. 15 according to an embodiment of the present invention. [Figure 16C] 16A-16C are cross-sectional views of performing optical metrology at all points on a substrate using the steps set forth in FIG. 15 according to an embodiment of the present invention. [Figure 16D] 16A-16C are cross-sectional views of performing optical metrology at all points on a substrate using the steps set forth in FIG. 15 according to an embodiment of the present invention. [Figure 16E] 16A-16C are cross-sectional views of performing optical metrology at all points on a substrate using the steps set forth in FIG. 15 according to an embodiment of the present invention. [Figure 16F] 16A-16C are cross-sectional views of performing optical metrology at all points on a substrate using the steps set forth in FIG. 15 according to an embodiment of the present invention. [Figure 16G] 16A-16C are cross-sectional views of performing optical metrology at all points on a substrate using the steps set forth in FIG. 15 according to an embodiment of the present invention. [Figure 16H]16A-16C are cross-sectional views of performing optical metrology at all points on a substrate using the steps set forth in FIG. 15 according to an embodiment of the present invention. [Figure 17] 10 is a flow diagram of a method for performing optical metrology at all points on a curved substrate for nP3, according to an embodiment of the present invention. [Figure 18A] 18A and 18B are cross-sectional views of performing optical metrology at all points on a curved substrate for nP3 using the steps described in FIG. 17 according to an embodiment of the present invention. [Figure 18B] 18A and 18B are cross-sectional views of performing optical metrology at all points on a curved substrate for nP3 using the steps described in FIG. 17 according to an embodiment of the present invention. [Figure 18C] 18A and 18B are cross-sectional views of performing optical metrology at all points on a curved substrate for nP3 using the steps described in FIG. 17 according to an embodiment of the present invention. [Figure 18D] 18A and 18B are cross-sectional views of performing optical metrology at all points on a curved substrate for nP3 using the steps described in FIG. 17 according to an embodiment of the present invention. [Figure 18E] 18A and 18B are cross-sectional views of performing optical metrology at all points on a curved substrate for nP3 using the steps described in FIG. 17 according to an embodiment of the present invention. [Figure 18F] 18A and 18B are cross-sectional views of performing optical metrology at all points on a curved substrate for nP3 using the steps described in FIG. 17 according to an embodiment of the present invention. [Figure 18G] 18A and 18B are cross-sectional views of performing optical metrology at all points on a curved substrate for nP3 using the steps described in FIG. 17 according to an embodiment of the present invention. [Figure 18H]18A and 18B are cross-sectional views of performing optical metrology at all points on a curved substrate for nP3 using the steps described in FIG. 17 according to an embodiment of the present invention. [Figure 19A] 10A-10C are graphs illustrating the effect of capillary forces of a contouring material in a tensioned web superstrate in various examples, in accordance with embodiments of the present invention. [Figure 19B] 10A-10C are graphs illustrating the effect of capillary forces of a contouring material in a tensioned web superstrate in various examples, in accordance with embodiments of the present invention. [Figure 19C] 10A-10C are graphs illustrating the effect of capillary forces of a contouring material in a tensioned web superstrate in various examples, in accordance with embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] In the electronic device field, roll-to-roll processing, also known as web processing, reel-to-reel processing, or R2R, is the process of creating electronic devices on a roll of flexible plastic or metal foil. In other fields that predate this use, roll-to-roll processing can refer to any process that begins with a roll of flexible material and then rewinds it to create an output roll. These processes, and others such as sheeting, can be grouped together under the general term conversion. Once the roll of material is coated, laminated, or printed, it can subsequently be slit to finished size in a slitter-rewinder.

[0012] Although roll-to-roll fabrication is an inexpensive process, it has not been available with precise nanoscale patterning.

[0013] The principles of the present invention provide a means for nanoscale precision programmable profiling. Specifically, the principles of the present invention relate to a novel process called nanoscale precision programmable profiling (nP3) and its apparatus. Examples of apparatus for implementing nP3 on flat and curved substrates are described herein. In one embodiment, a flexible web is used as a superstrate, mounted on a web handling system that can remove and reapply a protective film from the web. Inkjet printing is used to dispense a programmable pattern of UV-curable profiling material onto the substrate or superstrate. The superstrate and substrate, with the profiling material between them, are brought into contact through normal force generated by air pressure on the superstrate side and a vertical-tip-tilt stage on the substrate side. Air pressure is supplied through a UV-transparent chuck that can grip the web at the edges while transmitting UV light through the center. As the droplet spreads due to the superstrate-substrate contact, the droplet is UV-cured and the superstrate is separated from the substrate, leaving behind a hardened contouring material with the desired surface contour at the substrate. The substrate is mounted on a chuck on a linear stage that carries the substrate to a metrology station for real-time feedback. The substrate is returned to the contouring zone for further processing, if necessary. At any point in time, the location of the substrate is known relative to a reference to within 10 micrometers.

[0014] Referring now in detail to the figures, FIG. 1 is a schematic diagram of an nP3 device 100, in accordance with an embodiment of the present invention.

[0015] The nP3 device 100 consists of two main subsystems: a contouring subsystem 101 and a metrology subsystem 102. The contouring subsystem includes a web handling module consisting of unwind rollers, take-up rollers, rollers for interleaving and deinterleaving, drive rollers, nip rollers for tension control, and precision rollers to ensure a flat area. Lateral registration ensures that the webs wrap over each other without lateral error (stretching). Inkjet printheads in the registration stage dispense droplets of contouring material. UV lamps and a UV-transparent (UVT) chuck are used to cure the contouring material and to hold the superstrate in place while creating a pneumatically induced curvature to spread the droplets. A voice coil motor-driven flexible support stage holds the substrate chuck below the superstrate and is mounted on a linear horizontal stage 103 as shown. The metrology subsystem includes a sensor (Shack-Hartmann sensor, optical profilometer, interferometer, optical profilometer, reflectometer, or spectrophotometer) for measuring surface topography mounted directly above the substrate. A laser beam is guided through the substrate and incident on the sensor. This is necessary when the telescoping system handles curved substrates with a range of spherical powers. The laser beam alignment system includes a reflecting mirror that directs the horizontal laser beam vertically upward through the substrate. In one embodiment, the nP3 device 100 also has a communications module that enables local data transfer and exchange with other computers or other remotely located data centers / workstations (e.g., cloud-based data centers, cloud-based workstations). This data can include metrology data, tool sensor data, drop pattern data, etc.

[0016] Referring again to FIG. 1, the nP3 apparatus 100 further comprises a support table 104 with a granite base.

[0017] Reference is now made to FIG. 2, which is a schematic diagram of a contouring subsystem 200 in the nP3 device 100, in accordance with an embodiment of the present invention.

[0018] 2 , the contouring subsystem 200 includes motorized interleaf / deinterleaf rollers 201, nip rollers 213, a lateral register module 202, precision idler wheels 203, a UV-transparent vacuum chuck 119, a voice coil motor (VCM)-driven stage 204 for vertical, tip, and tilt motion, motorized supply and take-up rollers 205, drive rollers 206, a curing module 207, a stationary inkjet printhead 208, contouring material 209, a rigid substrate 210, a vacuum pin chuck 211, and a large-travel stage 212. In one embodiment, the rigid substrate 210 is either nominally flat or nominally non-flat (e.g., spherical, aspherical). As used herein, a “rigid” substrate means having a permanent shape and form. "Nominally flat" as used herein means a surface having distinct areas of contact that are so large that the individual contacts are distributed and forces acting through adjacent locations do not affect each other. "Nominally non-flat" as used herein means a surface that is not nominally flat.

[0019] As shown in FIG. 2, inkjet printhead 208 is stationary relative to a large direction of travel 212 .

[0020] FIG. 2 further illustrates the web path followed by the superstrate and interleaf film during removal and reapplication. In FIG. 2, tension control is achieved through a nip and drive roller assembly (see 213 and 206). In one embodiment, a polyurethane roller is used to apply normal pressure to the drive roller 206, which improves friction and allows for greater tension than is limited by motor capabilities. In one embodiment, the nip roller 213 ensures axial parallelism with the drive roller 206. A UV lamp is located directly above the contouring zone. A UV-transparent chuck 119 is positioned between the superstrate and the UV lamp. Precision idler wheels 203 are shown to flatten the superstrate and ensure minimal out-of-plane and in-plane errors. A voice coil motor stage 204 is mounted on a horizontal XY stage. The substrate is translated laterally from the spray station to the contouring station and then to the metrology station using the XY stage.

[0021] 3 is a schematic diagram of a contouring subsystem 300 having an alternative web handling system in accordance with an embodiment of the present invention. The contouring subsystem 300 is the same as the contouring subsystem 200 of FIG. 2, except for the differences described below.

[0022] Referring to FIG. 3, contouring subsystem 300 (in contrast to contouring subsystem 200) comprises a UV transparent, vacuum pre-loaded air bearing section 301 and a vacuum roller 302.

[0023] As shown in Figure 3, a pair of vacuum rollers 302 are used to provide tension to the superstrate in the contouring area. The vacuum rollers 302 provide tension without the normal compressive force on the superstrate, which may be necessary if a sensitive material is deposited on the superstrate. The normal force created by the vacuum is sufficient to create the desired tension (approximately 100 N / m to 1000 N / m).

[0024] FIG. 4 is a diagram illustrating the structure of a lateral register mechanism 400 in accordance with an embodiment of the present invention.

[0025] Referring to FIG. 4, lateral register mechanism 400 includes motor-driven deinterleaf rollers 401, load cell rollers 402, nip rollers 213, unwind feed rollers 403, sensors 404 for reel diameter measurement, and linear motors 405 that move lateral register module 400 across the web relative to stationary frame 406.

[0026] In FIG. 4, lateral register mechanism 400 includes deinterleaf roller 401, load cell roller 402, nip roller 213, linear support 403 across web motion, tie beam 103, edge sensor 105, unwind roller 404, load cell roller 405, drive roller 206, and lateral register actuator 104 (out of plane motion).

[0027] As shown in Figure 4, a lateral register correction module 400 is used to ensure that accumulated errors (stretching) do not cause lateral displacement of the web. In one embodiment, the load cell roller 402 and nip roller 213 upstream of the contouring zone are mounted on a carriage that can translate perpendicular to the web motion. A sensor 404 is used to determine the lateral position of the superstrate, along with limit switches to detect the ends of the travel range. Registration accuracies of less than 100 micrometers are obtained using the lateral register correction mechanism 400.

[0028] FIG. 5 illustrates a superstrate tension control system 500 according to an embodiment of the present invention.

[0029] As shown in FIG. 5, the superstrate tension control system 500 includes a motor-driven feed and rake roller 501, a motor-driven deinterleaf roller 401, a load cell roller 402, a nip roller 213, a precision idler wheel 203, a drive roller 206, and a sensor 404 for reel diameter measurement.

[0030] Tension control is maintained in three zones as shown in Figure 5. In one embodiment, nip rollers 213 are used to maintain tension in the contouring zone 502. Unwinding and rewinding maintain tension throughout the web. Load cell rollers 402 and sensors 404 are used to calculate tension in each zone. These sensor inputs are fed into motion controllers that drive motors to achieve the appropriate tension control.

[0031] 6A-6B illustrate a system 600 for precision alignment of an idler wheel in a contouring zone, according to an embodiment of the present invention.

[0032] As shown in FIGS. 6A-6B, the system 600 includes a YZ stage 601, a self-aligning ball bearing 602, and a precision idler wheel 203 (low runout).

[0033] 6A-6B depict the precision idler system and roller orientation adjustment mechanism. Precision idler roller 203 is mounted on a YZ stage 601 as shown. Self-aligning ball bearings 602 are used at both ends of roller 203. In one embodiment, YZ stage 601 is positioned on the sidewall through line boring. A laser tracking sensor can be used to measure the misalignment between any two rollers in the system, allowing a flat contoured zone to be created (without web shift and out-of-plane errors).

[0034] 7A-7B and 7C1-7C3 illustrate a UV-transmissive vacuum chuck 701 with a gap measurement sensor according to an embodiment of the present invention. Referring to FIG. 7A, FIG. 7A illustrates a side view of a UV-transmissive (UVT) vacuum chuck 701 when the vacuum is off, the cavity air pressure is off, and the precision alignment system is in a rest mode, according to an embodiment of the present invention. In such mode, a micrometer knob 702 is attached to a ball end 703 that is bonded to a micrometer actuator via a micrometer mount 704. As shown in FIG. 7A, the ball end 703 is protected via a ball sleeve 705. Also shown in FIG. 7A, in some embodiments, there may be a stationary plate 706 to which the micrometer is fastened. Furthermore, as shown in FIG. 7A, UV light is emitted from a UV lamp 707. Also shown in FIG. 7A is a superstrate web 708 and a substrate 709.

[0035] 7B shows a side view of a UV-transparent (UVT) vacuum chuck 701 when the vacuum is on, the cavity air pressure is on, and the precision alignment system is in chuck mode, in accordance with an embodiment of the present invention. In such mode, an air cavity 710 exists between the UV-transparent vacuum chuck 701 and the superstrate 708, with a gap of less than 100 micrometers.

[0036] Figures 7C1-7C3 show cross-sectional side views of a UV-transparent (UVT) vacuum chuck 701 that includes a UVT (ultraviolet light transmitting) acrylic plate 711 and a porous region 712 with through-holes 713 at the edges to the chuck / transport web as shown in Figure 7C3, which shows the UV-transmitting region. Figure 7C3 also shows a vacuum supply 713 and a support 714 with a positive pressure supply. Figure 7C3 also shows a bottom plate 715 of the UVT vacuum chuck 701 that includes a porous material for passing air pressure to the web.

[0037] 8A-8C show a voice coil motor driven flexible support stage 204 for vertical-tip-tilt motion, according to an embodiment of the present invention.

[0038] 8A-8C, which depict a stage for vertical motion and tip and tilt alignment. Three actuators 801 are mounted vertically on a base plate 802, as shown in FIG. 8A. The vertical motion of the actuators is defined by flexible translational joints designed to increase the range of motion while maintaining high stiffness. Limit switches and mechanical hard stops are added to sense the ends of the travel range and to avoid damage to the motors and bearings.

[0039] Specifically, Figure 8A shows a flexible support 803 (Figure 8C shows a detailed view of flexible support 803) coupled to a base plate 802 and a translating flexible support 804 (Figure 8B shows a detailed view of translating flexible support 804). In one embodiment, a displacement sensor 805 is located on the translating flexible support 804, which is coupled to a stationary chassis 806. Also shown in Figure 8A, each actuator 801 includes a voice coil motor 807.

[0040] 9A, 9A1, 9B-9C show a substrate chuck having a transmissive central region for optical metrology according to an embodiment of the present invention.

[0041] 9A, which shows a pin chuck for a flat substrate having a transmissive central region according to an embodiment of the present invention. As used herein, "flat substrate" refers to a substrate having a smooth, uniform surface without any irregularities.

[0042] FIG. 9A further shows a chuck area with pins 901, a transparent area 902 for metrology, a recessed ring 903 for holding the vacuum, and a vacuum pad 904 for placing the base plate.

[0043] FIG. 9A1 shows a magnified image 905 of a pin, according to an embodiment of the present invention.

[0044] FIG. 9B illustrates a substrate chuck having pins 906 for gripping and a transmissive region 907 for optical metrology, according to an embodiment of the present invention.

[0045] FIG. 9C shows a three-point chuck for curved substrates according to an embodiment of the present invention.

[0046] 9A, 9A1, 9B-9C depict substrate chucks for flat and curved substrates. An annular vacuum pin chuck 906 is used to support the flat substrate at the edge while an air cavity is created in the center region to create the curvature. In one embodiment, the curvature is used to ensure bubble mitigation. This allows the center region 907 to be transparent to the laser beam required for optical metrology of the surface topography. For curved substrates, a three-point chuck is used to grip the substrate at the edge, making the center region 907 transparent to the laser beam. Both of these chucks are mounted to a base plate in a voice coil motor-driven stage using vacuum pads 904.

[0047] 10A-10B show an alignment mechanism for parallelism between a superstrate and a substrate, according to an embodiment of the present invention.

[0048] Referring to Figure 10A, Figure 10A shows a UV transfer chuck 1001 with an integrated capacitance sensor, a superstrate 1002 on a precision idler wheel, a pin chuck 1003 with an integrated capacitance sensor, and a VCM stage 204 for vertical, tip, and tilt motion. Figure 10B shows a metal membrane 1004 for side-by-side gap measurement via a capacitance sensor.

[0049] 10A-10B are schematic diagrams of a mechanism deployed to ensure parallelism between a UV-transparent chuck 1001 with an integrated capacitance sensor, a superstrate web 1002 on precision idler wheels, and a substrate chuck 1003. The VCM stage 204 is automatically controlled. The substrate chuck 1003 mounted on the VCM stage 204 and the UVT chuck 1001 are equipped with integrated capacitance sensors. The pitch and roll angles of the UVT chuck are manually adjusted using air supports mounted to a kinematic coupling. The metal superstrate web 1004 is laterally moved through precision idler wheels mounted on a manual alignment stage, while enabling capacitance sensing. Measurements from the capacitance sensors align the substrate chuck with the superstrate web 1002 and the UVT chuck 1001 with the superstrate web 1002. Parallelism can thereby be maintained between the three objects with microradian accuracy.

[0050] 11A-11C illustrate an inkjet assembly and fixture for large area inkjet according to an embodiment of the present invention.

[0051] Referring to FIG. 11A, FIG. 11A shows a large width inkjet assembly.

[0052] FIG. 11B shows a bottom view of the large width inkjet assembly.

[0053] 11C shows the inkjet fixture flexible mechanism design 1101 (Yθ operation). As shown in FIG. 11C, the inkjet fixture flexible mechanism design 1101 includes a fixed body 1102, a flexible rotational coupling 1103, and a manual actuator 1104.

[0054] Referring to Figures 11A-11C, in one embodiment, inkjet drops are deposited uniformly across a large width (approximately 500 mm) with sub-100 micrometer precision. Therefore, all inkjet heads are mounted on a stage with flexible supports that allow motion in Y (transverse to the web or plate) and θ. Combining multiple such inkjet stages provides the necessary degrees of freedom for the fixture and a sufficient range of motion to distribute the drops uniformly. Alternatively, a smaller inkjet fixture may be mounted on a linear stage with sub-micrometer precision and used to distribute drops along the width. In one embodiment, this may be necessary for nP3 on curved substrates while dispensing contouring material onto a superstrate web. For nP3 on flat substrates, the inkjet is mounted on a manual stage with the following degrees of freedom: roll, pitch, and motion in the vertical and horizontal axes transverse to the substrate.

[0055] 12A-12B show the structure of an nP3 metrology subsystem 1200, according to an embodiment of the present invention.

[0056] Referring to Figures 12A-12B, Figures 12A-12B show the optical sensor 1207, alignment stage 601, telescoping lens 1201, cage mounting hardware 1202, translating 45 degree mirror 1203, stationary reflector 1204, linear stage 1208, location of substrate and VCM stage during metrology 1205, and aluminum extrusion mounting station 1206.

[0057] As shown in Figures 12A-12B, the metrology unit consists of a laser source and an alignment mirror that directs the beam toward a stationary mirror 1204, which directs the beam upward. Here, the beam can propagate through a transparent substrate. Variations in the beam's optical properties (intensity, amplitude, etc.) are produced by the surface topography as a function of deviation from a perfectly flat surface. An automated telescoping system is used to ensure the beam remains parallel while incident on the sensor plane. An optical sensor 1207 is positioned above the substrate and can measure topology data over an area of ​​less than 15 mm. An XY stage 1208 is scanned in the horizontal plane to cover the entire surface of the substrate and collect surface contour data.

[0058] 13A-13B illustrate a laser beam alignment module in an nP3 optical metrology module, according to an embodiment of the present invention.

[0059] 13A-13B, a laser beam 1301 from a laser 1302 travels through a collimator and neutral density filter onto a pair of alignment mirrors. The laser beam 1301 then strikes a pair of reflecting mirrors 1303, 1304, which direct the beam vertically onto the substrate (identified as the "target"). These reflecting mirrors can be aligned based on the desired deflection into the beam path. In one embodiment, these mirrors are 45-degree mirrors. The reflecting mirrors are mounted as shown (see kinematic mounts 1305, 1306) to ensure that the X-stage carriage is positioned completely below the substrate when in the measurement region.

[0060] 14A-14B illustrate an automatic telescoping system 1400 in a metrology module, according to an embodiment of the present invention.

[0061] 14A-14B, the automatic telescopic system 1400 includes an optical sensor 1207, an alignment stage 601, a telescopic lens 1201, a translating 45-degree mirror 1203, a stationary reflecting mirror 1204, and a translation stage 1401 for adjusting the optical path length.

[0062] In one embodiment, the automatic telescoping system 1400 is positioned downstream of the substrate. As shown in Figures 14A-14B, the beam first passes through a convex lens, then passes to a series of reflecting mirrors 1203 and 1204, and passes through a convex lens again. The beam exiting the second convex lens is parallel to the sensor axis. To ensure that the beam is parallel and that the lenses are positioned to interface with each other, the optical path length between the lenses is changed by adjusting the positions of the reflecting mirrors 1203 and 1204. The mirrors are mounted on a linear stage that can change the optical length between convex lenses 1 and 2 so that the exiting beam is parallel for a range of curved substrates with spherical powers between -15D and 15D. The optical path length between convex lenses 1 and 2 can be automatically adjusted based on feedback from the optical sensor 1207.

[0063] In one embodiment, an optical profilometer is used to measure changes in surface topography for flat substrates. Optical profilometers work on the principle of interference and can detect changes as small as 1 nm or less. In one embodiment, a Shack-Hartmann wavefront sensor is used to measure the wavefront of light transmitted through a curved substrate. If the incoming wavefront is planar, deviations in the shape of the wavefront can measure the topography of the substrate. The SH sensor has a two-dimensional array of light that is focused by lenslets at sensor pixels. Based on the divergence of the incoming light beam and its deviation from a perfectly paraxial beam, the surface contour can be measured with sub-nm accuracy and a pitch of 100 micrometers.

[0064] Figure 15 is a flow diagram of a method for performing optical metrology at every point on a substrate, according to an embodiment of the invention. Figures 16A-16H depict cross-sectional views of performing optical metrology at every point on a substrate using the steps set forth in Figure 15, according to an embodiment of the invention.

[0065] 15 in conjunction with FIGS. 16A-16H, in step 1501, as shown in FIG. 16A, contouring material 1601 is dispensed onto substrate 1602 using inkjet 1603. In one embodiment, the contouring material dispense location is determined using an algorithm executed at one of the following locations: a local computer, a remote computer, and a cloud-based computer.

[0066] In step 1502, the superstrate 1604 is positioned under the UVT chuck 1605 and tensioned, as shown in Figure 16B.

[0067] In step 1503, as shown in Figure 16C, the superstrate 1604 is gripped using a UVT chuck 1605. Further in step 1503, air pressure is applied to initiate contact (between the superstrate 1604 and the substrate 1602), as shown in Figure 16C.

[0068] In step 1504, the air pressure is gradually increased until all the drops coalesce, as shown in Figure 16D.

[0069] In step 1505, pressure from an air bar is applied continuously with a UV (ultraviolet) flash 1606 to form a continuous film 1607, as shown in Figures 16E and 16F.

[0070] In step 1506, the substrate 1602 is separated from the superstrate 1604 using a VCM stage 1608, as shown in Figure 16F.

[0071] In step 1507, the substrate 1602 and VCM stage 1608 are moved to the metrology station 1609 using the x-stage 1610, as shown in Figure 16G.

[0072] In step 1508, as shown in Figure 16H, the xy stage is scanned to perform optical metrology via laser beam 1611 at all points on substrate 1602 (corresponding to the final substrate contour).

[0073] A more detailed description of the method 1500 in connection with Figures 16A-16H is provided below.

[0074] During nP3 on the flat substrate, a drop pattern 1601 is generated and distributed over a large area on the flat substrate 1602. This is achieved through XY motion of the substrate, synchronized with the spray cycle. The substrate 1602 is then moved laterally into a contouring zone beneath a UV lamp and UVT chuck 1605. Tension in the superstrate 1604 is adjusted to the desired level required by the final surface contour. The superstrate 1604 can be a textured or patterned roll, with the lateral spatial length scale of the texture or pattern being at least an order of magnitude smaller than the lateral spatial length scale of the desired contouring. The UVT chuck 1605 is then used to hold the superstrate 1604 in place. A voice coil motor-driven stage, with the substrate mounted on the chuck, is brought to the contouring zone using a horizontal XY stage. Vertical, tip, and tilt motion of the VCM stage 1608 allows for proper alignment and gap control of the substrate 1602 with the superstrate 1604. Air pressure is increased in the cavity to create a curvature in the superstrate web, causing the droplets to coalesce and form a continuous film 1607. This allows trapped air bubbles to be alleviated. A camera mounted on the UVT chuck 1605 is used to observe the trapped air bubbles. Using image processing, bubbles are identified, and air is automatically siphoned up in the superstrate 1604 at the target location to ensure the droplets spread and the bubbles are alleviated. After a specific period of time required for capillary forces to create the desired topography, the contouring material is UV cured. A VCM stage 1608 is used to separate the substrate 1602 from the superstrate 1604 through its vertical movement. The substrate 1602, along with the VCM stage 1608, is carried to the metrology station 1609. The VCM stage 1608 helps align the surface of the substrate 1602 at the point of measurement with the optical axis of the optical profilometer. A laser beam 1611 is transmitted through the substrate 1602 to the SH sensor through an automated telescoping system (to accommodate different powers).An XY stage is used to scan the substrate 1602 in a horizontal plane to measure the topography at every location on the substrate 1602. Once the measurements are performed, a decision is made as to whether further processing is required (e.g., for multi-step processes where the surface topography has high amplitudes). The horizontal stage returns the substrate to the contouring zone if processing is required. A communications module in the tool can be used to transfer and exchange data related to substrate metrology, tool sensors, and drop patterns.

[0075] Figure 17 is a flow diagram of a method for performing optical metrology at all points on a curved substrate for nP3, according to an embodiment of the present invention. Figures 18A-18H depict cross-sectional views of performing optical metrology at all points on a curved substrate for nP3, using the steps set forth in Figure 17, according to an embodiment of the present invention.

[0076] 17 in conjunction with FIGS. 18A-18H, in step 1701, as shown in FIG. 18A, contouring material 1801 is dispensed onto superstrate 1802 using inkjet 1803. In one embodiment, the contouring material dispense location is determined using an algorithm executed at one of the following locations: a local computer, a remote computer, and a cloud-based computer.

[0077] In step 1702, a superstrate 1802 is positioned and tensioned under a UVT chuck 1804, as shown in Figure 18B. Figure 18B also shows a substrate 1805.

[0078] In step 1703, as shown in Figure 18C, the superstrate 1802 is gripped using a UVT chuck 1804. Further in step 1703, air pressure is applied to initiate contact (between the superstrate 1802 and the substrate 1805), as shown in Figure 18C.

[0079] In step 1704, the air pressure is gradually increased until all the drops coalesce, as shown in Figure 18D.

[0080] In step 1705, pressure from an air bar is applied continuously with a UV (ultraviolet) flash 1806 to form a continuous film 1807, as shown in Figures 18E and 18F.

[0081] In step 1706, the substrate 1805 is separated from the superstrate 1802 using a VCM stage 1808, as shown in Figure 18F.

[0082] In step 1707, the substrate 1805 and VCM stage 1808 are moved to the metrology station 1809 using the x-stage 1810, as shown in Figure 18G.

[0083] In step 1708, as shown in Figure 18H, the xy stage is scanned to perform optical metrology via laser beam 1811 at all points on substrate 1805 (corresponding to the final substrate contour).

[0084] A more detailed description of the method 1700 in connection with Figures 18A-18H is provided below.

[0085] Here, the steps for the nP3 process on a nominally non-planar substrate are listed. As used herein, a "non-planar" substrate means a substrate having a non-flat surface (i.e., not a smooth, uniform surface). While this description is related to substrates with nominally spherical curvature, substrates with nominally aspherical curvature and other free-form substrate contours can also be fabricated using the same process flow.

[0086] During nP3 on the curved substrate, a drop pattern 1801 of contouring material is generated and dispensed onto a superstrate 1802. The superstrate 1802 can also be a textured or patterned roll, with the lateral spatial length scale of the texture or pattern being at least an order of magnitude smaller than the lateral spatial length scale of the desired contouring. The speed of the superstrate web is synchronized with the spray time period to maintain drop placement accuracy. The drop locations also correspond to the desired locations on the non-flat substrate 1805, such that, in conformal contact with the substrate 1805, the drops are positioned where needed on the substrate 1805. The superstrate region with the deposited drops is translated laterally into a contouring zone beneath UV lamps 1806 and a UVT chuck 1804. Tension in the superstrate 1802 is adjusted to the desired level required by the final surface contour. The UVT chuck 1804 is then used to hold the superstrate 1802 in place. A voice coil motor-driven stage, on which the substrate 1805 is mounted on a chuck, uses a horizontal XY stage to move to the contouring zone. The chuck can be equipped with three pins to support varying curvatures. The vertical, tip, and tilt motion of the VCM stage 1808 allows for proper alignment and gap control of the substrate 1805 with the superstrate 1802. Air pressure is increased in the cavity to create the curvature of the superstrate web, thereby fusing the droplets to form a continuous film 1807. This allows for the mitigation of trapped air bubbles. A camera mounted on the UVT chuck 1804 is used to observe bubble trapping. Using image processing, bubbles are identified, and air is automatically wicked up from the superstrate 1802 at the targeted location to ensure the droplets spread and the bubble is mitigated. After a specific period of time required for capillary forces to create the desired topography, the contouring material is UV-cured. The VCM stage 1808 is used to separate the substrate 1805 from the superstrate 1802 through its vertical movement.The substrate 1805, along with the VCM stage 1808, is carried to the metrology station 1809. The VCM stage 1808 helps align the normal to the curved surface of the substrate 1805 at the point of measurement with the optical axis of the SH sensor. A laser beam 1811 is transmitted through the substrate 1805 to the SH sensor via an automated telescoping system (to accommodate different degrees of magnification). The XY stage is used to scan the substrate 1805 in the horizontal plane to measure the topography at every location on the substrate 1805. Once the measurements are performed, a decision is made as to whether further processing is required (e.g., for a multi-step process where the surface topography has high amplitudes). The horizontal stage returns the substrate 1805 to the contouring zone if processing is required. A communication module in the tool can be used to transfer and exchange data related to substrate metrology, tool sensors, and drop patterns.

[0087] In some embodiments, in-situ measurements may be performed using an optical profilometer, a Shack-Hartmann sensor, or both. The signal must be isolated from noise in the measurement, which can arise from multiple sources, such as fluctuations in beam intensity, distortions in optical components used in the beam path, mechanical vibrations, camera sensor noise, and thermal fluctuations. These noise sources must sometimes be characterized to ensure reliable instrument operation. Some of this noise is systematic in nature and can be removed from the signal (e.g., the presence of aberrations in optical components). However, some of this noise is random and can substantially distort the signal. For example, vibrations are a significant source of random noise that can degrade the signal by displacing the optical mechanical installation or the beam path, with larger beams or optical components causing more pronounced deviations. Such vibrations typically manifest as fluctuations in lower-order aberrations (tip, tilt, defocus, and astigmatism) and typically do not affect higher-order aberrations by remaining within ±10 nm of the desired Zernike coefficients of the HOA. The area of ​​HOA correction for ophthalmology, as described later, does not result in loss of measurement accuracy. To minimize fluctuations in the measurement of lower-order aberrations for precision optics, multiple measurements can be taken to extract an averaged signal using noise filtering techniques such as a Kalman filter. This technique may result in lower throughput but can provide greater measurement accuracy for precision optical substrate contouring.

[0088] A formulation consists of a material, such as a UV-curable contouring material, that contains significant amounts of components. Suitably, the formulated system can perform satisfactorily over a range of compositions. The formulation may take into account the anticipated amount of material that will need to be evaporated so that the optimal range of component ratios is not disturbed. Furthermore, certain components, such as photoinitiators or crosslinkers, are almost always less volatile, as can be seen in the table below.

[0089] The contouring material formulation may include a mixture of some or all of the following ingredients: initiator, polymerizable monomer with one active group, polymerizable monomer with two or more active groups, technically referred to as a crosslinker, and surfactant. This list is not comprehensive as other ingredients may be present depending on the desired performance and application.

[0090] Examples of relevant ingredients are shown in the table below.

[0091] [Table 1]

[0092] Downstream processing considerations can preclude the use of UV-crosslinkable polymers. For example, most methacrylic acid polymers have a Tg of approximately 150°C. Any downstream heat treatment above 150°C can damage the material. There are thermoplastic polymers, such as polyimides, that have a much higher Tg of approximately 350°C. Therefore, using these polymers can alleviate concerns associated with heat treatment. However, these materials are very viscous, making them difficult to coat in substantially smaller amounts. To accomplish this, polyimide materials can be diluted in solvents, which reduces their viscosity and makes them more amenable for coating. The solvent needs to be completely evaporated to minimize condensation on the substrate. This is accomplished by using solvents with substantially higher volatility (e.g., MIBK, ethyl acetate) and by using a heated substrate chuck or IR lamps to completely and quickly evaporate the solvent.

[0093] The superstrate roll can be created with the aid of different plastic materials, such as polycarbonate, PET, PEN, or polyimide. The superstrate roll can also be made from flexible glass (e.g., Willow glass from Corning). In some embodiments, the superstrate does not have a texture or pattern on the superstrate. A texture or pattern can be used to impart functional properties to the substrate in addition to the desired contouring. For example, a nanoscale texture in the form of a conical pillar can provide antireflection at the interface as a moth-eye structure. This eliminates the need to deposit alternating low-refractive-index and high-refractive-index films. Thus, the texture combined with the contouring can impart antireflection aberration control to the substrate. Nanoscale patterns can also be used to impart self-cleaning properties, for example, in situations where contour correction is desired for surfaces that may be exposed to the environment. In some embodiments, the superstrate has a texture or pattern, and the lateral spatial length scale of the texture is at least one order of magnitude smaller than the order of magnitude of the desired contouring in the substrate. In some embodiments, the texture is similar to a moth-eye structure. In some embodiments, the texture or pattern is formed from the same contouring material in the substrate. In some embodiments, the texture or pattern is formed from a different material than the contouring material.

[0094] A fluid-template interaction model is used to calculate the effect of capillary forces on a tensioned web, specifically to determine whether the web will collapse under capillary forces. A quantified relationship between applied tension and film thickness change has also been found. Based on lubrication theory characterizing thin film flow, the following PDE governs the physics of fluid-web interaction:

[0095]

number

[0096] where h1 = contouring material film thickness, h2 = template web clearance from substrate in areas without contouring material, Pf = fluid pressure, Pa = pressure from air bearing, and T0 = applied web tension. The solution is assumed to be of the following form:

[0097]

number

[0098] The equations are solved numerically using continuity, differentiability, and capillary pressure difference boundary conditions at the fluid-air interface and symmetry elsewhere.

[0099] 19A-19C graphically illustrate the effect of capillary forces of contouring material on a tensioned web superstrate in various examples according to embodiments of the present invention. Line 1901 shows the area of ​​contouring material liquid and the superstrate web profile in that area, while line 1902 shows the superstrate web profile in an area without contouring material. Line 1903 shows the substrate. The graphs illustrate the spreading of a drop under capillary forces and a tensioned web. Film thickness variations are observed to be unavoidable for small applied tensions.

[0100] Prevention of contamination is an important attribute of this device. Typically, particle contamination can be minimized by maintaining a positive pressure inside the device with constant recirculation. Air handling inside the device can be based on cross-flow so that air drafts to the user are minimized while maintaining a positive pressure inside the device.

[0101] A digital twin of a manufacturing tool is a model-based representation of the tool that is used to monitor and predict the tool's performance and yield. Digital twins are often utilized in cutting-edge manufacturing environments (e.g., semiconductor manufacturing) where there is a substantial amount of data available from sensors on the tool. As such, data from the sensors is analyzed with the aid of data analytics techniques regarding the tool's output (in terms of yield, performance, etc.) so that a model of the tool is constructed. This model may be entirely data-based or may have a physically-based foundation. In one embodiment of this invention, a digital twin is created for an nP3 tool.

[0102] Human vision can be significantly affected by the presence of higher order aberrations (HOAs), which are typically not corrected by conventional eyeglass lenses. This can result in halos, starbursts, ghost images, and the like, especially when working in low light conditions, such as nighttime operation. HOAs are expressed in the form of Zernike polynomials. Typical HOAs present in the human eye include coma, trefoil, and spherical aberrations, and are known to deteriorate vision. Each eye has a unique HOA profile and may simultaneously have multiple aberrations. Disclosed herein is the use of the nP3 process to fabricate HOA-corrected lenses for use in human vision.

[0103] Conventional eyeglass lenses are fabricated by using diamond machining tools to cut injection-molded lens blanks into the desired ophthalmic prescription (typically consisting of geometric parameters such as sphere, cylinder, "add" power to address presbyopia, and interpupillary distance). Lens blanks are made from materials such as polycarbonate, CR-39, and Trivex and are typically available in diameters of 65 mm to 80 mm in power increments of 0.25D or 0.125D. These lens blanks may be curved and coated with a "hard coat" to provide scratch resistance and reduce the presence of diamond machining artifacts, and may also be coated with an anti-reflective coating to increase transmission through the lens.

[0104] Traditionally manufactured eyeglass lenses cannot correct for HOA, which can be problematic and prevent people from achieving optimal vision. The principles of the present invention disclose the use of the nP3 process for curved substrates (as previously described) to deposit a programmable film of contouring material onto a lens blank so that the contour needed to correct HOA can be added to an existing lens blank that already corrects for the patient's apparent spherical and cylindrical powers. This allows for the customization of each lens blank to the eye's HOA contour, without traces such as tool marks from diamond machining or roughness from orange peel as a result of uneven evaporation of the liquid coating. Furthermore, a contouring material with a refractive index substantially similar to that of the lens blank material can enable the creation of a seamless optical interface between the underlying lens blank and the HOA contour. For example, the refractive index of polycarbonate (approximately 1.55) is very close to that of acrylate-based contouring materials (approximately 1.54), making this combination well-suited for nP3 on polycarbonate lens blanks.

[0105] For this purpose, the HOA in the eye is first measured using a wavefront aberrometer (e.g., the Nidek OPD Scan series) or an ophthalmic lens (described later) paired with the individual's HOA. An opposing HOA contour is generated that can substantially correct the eye's existing HOA. This opposing HOA contour may not completely cancel all existing HOA, and the amount of cancellation required to substantially improve vision to accommodate the individual's lifestyle is obtained with the aid of optical models and simulations. These models and simulations include techniques such as geometric ray tracing, wavefront analysis, and Fourier optics, as well as the use of wavefront phase analysis, modulation transfer function (MTF), point spread function (PSF), and the like. For example, an artist may desire excellent resolution and compromise depth perception, while a driver may desire better depth perception to match reasonable resolution. Therefore, for the former, substantial cancellation of all HOAs may be important, while for the latter, some HOAs may be intentionally created to allow for better depth of field at the expense of resolution.In addition to the HOA contour, the diameter of the pupil is also measured.Based on personal preference, this measurement may be tailored to different light conditions, since the pupil is more dilated in low light conditions.For example, a person who wants to correct poor night vision may want to perform this measurement in low light conditions.

[0106] After measuring the HOA contour, a drop pattern is generated based on the desired HOA contour as well as the topography of the lens blank being used. The lens blank topography can be measured with the nP3 instrument in the measurement area and should substantially match the desired spherical and cylindrical powers for the eye. The desired drop pattern can be generated locally, remotely, or in the cloud. The desired HOA contour can be converted to film thickness by scaling it by a factor of (1 / n-1), where n is the refractive index of the film. In some embodiments, the area over which the drop pattern is generated and the nP3 process is performed is equal to the area of ​​the pupil measured above. In some embodiments, this area is different from the area of ​​the pupil. In some embodiments, this area is larger than the area of ​​the pupil to accommodate off-axis viewing over an angle corresponding to the best foveal angular resolution (±5 degrees). In some embodiments, this area is larger than the area of ​​the pupil to accommodate off-axis viewing over an angle corresponding to ±15 degrees (representing a sufficiently high angular resolution). In some embodiments, this region is larger than the pupil region to accommodate off-axis vision over angles corresponding to ±60 degrees (representing sufficient angular resolution for binocular vision). In some embodiments, multiple such regions can be positioned on a single lens blank to allow the eye to move relative to the head and see through the multiple regions in the blank. In some embodiments, these multiple regions are blended together into a single larger region. In some embodiments, the desired HOA correction contour is transitioned to the background substrate without the HOA contour using a smooth blending function (e.g., a Hanning window) rather than a sharp step in the transition. In some embodiments, the spectacle lens is actuated based on feedback from an eye tracking device to position the HOA correction region on the lens substantially parallel to the visual axis of the eye. This "active" centration method can improve visual acuity and result in "supernormal vision" because the incoming wavefront is corrected and focused on the fovea even when the eye moves relative to the head. The power source, actuators, and sensors for this embodiment can be placed in a specially designed spectacle frame.

[0107] In some cases, the desired HOA profile may result in the deposition of a film on the tool with a thickness that exceeds the maximum allowable thickness. Such cases include the presence of a condition such as keratoconus, in which the cornea is shaped like a cone rather than a sphere, resulting in abnormally high values ​​for HOA, such as coma. In such cases, the film may be deposited in multiple steps, each meeting some portion of the desired HOA / film thickness profile without introducing substantial process and metrology errors. Intermediate metrology may be performed upon completion of nP3 for each step, and, if desired, a drop pattern may be generated to correct for errors in the previous step and to deposit the film for the next step. Even if multiple steps may not be required, a second step, as described in this paragraph, may be used to clean up errors in the first step due to the film deposited in the first step remaining on the substrate. The presence of in-situ metrology in the tool allows this to be done without the substrate being removed from the tool.

[0108] In some embodiments, the nP3 process may be performed on a lens blank that has a hard coat layer. Following the nP3 process, an anti-reflective coating may be deposited according to standard practice in the lens manufacturing industry. In some embodiments, the nP3 process is performed on the lens blank as is, followed by the deposition of the hard coat and anti-reflective coating. In some embodiments, the nP3 process is performed on a tinted lens blank. In some embodiments, the nP3 process is performed on a lens blank that already has a coating.

[0109] Trial lenses are used by optometrists to determine an individual's prescription. They consist of glass plates / lenses with different spherical and cylindrical powers that can be encased in metal rings. Trial lenses are then fitted into trial frames, allowing the optometrist to try different combinations to determine the patient's optimal prescription. Currently available trial lenses only correct low-order aberrations—tip / tilt, defocus, and astigmatism—and do not address higher-order aberrations. The nP3 process can be used to generate trial lenses configured for an individual's HOA modes (e.g., coma, trefoil, and spherical aberration) with varying amplitudes for each mode. For example, a trial lens configured for spherical aberration can address aberrations with Zernike coefficients ranging from -0.5 microns to 0.5 microns in steps of 0.05 microns for a 7 mm pupil diameter. Furthermore, because these HOA-correcting trial lenses do not need to have spherical / cylindrical powers, they can be fabricated on flat substrates using the nP3 process. When used in series with conventional trial lenses (with spherical and cylindrical powers) in the same trial frame, the HOA-correcting trial lenses can be used to measure the approximate HOA of an individual's eye, along with standard low-order aberrations. These lenses may be used to simulate the effect of HOA correction on visual acuity.

[0110] In some embodiments, different ophthalmic lenses can be fabricated with varying regions where the HOA contour corresponds to different pupil diameters. The desired HOA contour can be converted to a film thickness by scaling it with a factor that depends on the refractive index of the film and substrate. In some embodiments, the region where the drop pattern is generated and the nP3 process is performed covers the off-axis field of view over an angle corresponding to the best foveal angular resolution (±5 degrees). In some embodiments, this region covers the off-axis field of view over an angle corresponding to ±15 degrees (representing a sufficiently high angular resolution). In some embodiments, this region covers the off-axis field of view over an angle corresponding to ±60 degrees (representing sufficient angular resolution for binocular vision). In some embodiments, multiple such regions can be positioned on a single ophthalmic lens to move the eye relative to the head and see through the multiple regions in the blank. In some embodiments, these multiple regions are blended together into a single larger region. In some embodiments, the desired HOA correction contour is transferred to the background substrate without the HOA contour using a smooth blending function (e.g., a Hanning window) rather than a sharp step in the transition. In some embodiments, several aberrations can be combined into a single trial lens substrate, for example to substantially correspond to the HOA contour of a typical person, or can be customized to the HOA contour of an individual's eye. Such trial lenses can be used to simulate the effect of HOA correction on an individual's eye before a similar contour is created in an actual lens blank. In some embodiments, the light transmission through a single trial lens substrate is greater than 90%. In some embodiments, the light transmission through three trial lens substrates held in series is greater than 90%. In some embodiments, the light transmission through five trial lens substrates held in series is greater than 90%.

[0111] Precision optical elements include mirrors and lenses for a wide range of applications. Depending on the application, such elements may need to be fabricated from different substrate materials and can be either flat, freeform, or nominally curved. The nP3 process can be used either to correct existing topography in a substrate to match a desired topography, or to create an entirely different contour from the starting substrate. In some applications, the nP3 process deposits a functional film that remains on the substrate. For example, for optical applications, the functional material can be a film with a refractive index that is substantially matched to the refractive index of the substrate at one or more wavelengths. For some applications, the nP3 process deposits a sacrificial film that can later be used to transfer the contours of the film to the substrate using an etching step. These applications include those in which the presence of a polymeric film can degrade the functionality of the substrate and therefore need to be removed, for example, for optics of high-intensity laser beams. The etching step is typically performed in a reactive ion etching (RIE) chamber using a plasma process that can be adjusted to obtain a desired ratio between the etch rate of the sacrificial contouring material and the etch rate of the underlying substrate material. In some embodiments, the ratio of the polymer etch rate to the etch rate of the underlying substrate or layer can be adjusted from 0.1 to 10. Based on the etch rate ratio, the profile of the polymer film can also be adjusted to obtain a desired profile on the substrate within a specific tolerance. The etching step itself can be divided into multiple coarse and fine steps, where a substantial amount of material can be removed in the coarse steps with a high etch rate for high throughput, and the fine steps correct for errors in the desired profile. Intermediate metrology can be performed between the coarse and fine steps. Furthermore, in some applications, an additional uniform film can be deposited on the nP3 process film. For example, a uniform metal layer can be deposited after the nP3 process to provide the substrate with optical reflectivity with the appropriate profile. An exemplary application of the nP3 process for precision optical surfaces is described next.

[0112] AR / MR, and collectively XR, headsets require the use of high-index waveguides to transmit light from the display to the pupil near the eye. This virtual image is superimposed on the real world perceived by the eye. These waveguides typically have a diffraction grating that couples at least one wavelength of light incident on the grating from the microdisplay into the waveguide at an angle that causes the light to undergo total internal reflection into the waveguide. Therefore, light is coupled out of the waveguide using one or more diffraction gratings. These waveguides are fabricated from substrates that must have good flatness and / or total thickness variation (TTV). This is because substantial deviations from a flat waveguide with near-zero TTV either shift the light beam from the desired path or cause the beam to change its diameter, thereby distorting the virtual image relative to the real image. Furthermore, these headsets can have multiple waveguides, each accommodating one or more wavelengths. Therefore, if each waveguide offsets its beam differently from other waveguides in the same headset, the combined image may introduce chromatic aberration.

[0113] Simulations show that the greater the number of reflections in the waveguide, the greater the distortion of the image at the exit pupil of the waveguide. The number of reflections is increased by increasing the distance between the coupled grating and the uncoupled grating or the exit pupil. Thus, light rays traveling further into the waveguide will experience greater deviation than desired if the waveguide is imperfect. The number of reflections is also increased when the substrate thickness is reduced to reduce the weight of the waveguide and thereby the weight of the headset itself.

[0114] The nP3 process for flat substrates can be used to correct the flatness and TTV in transparent waveguide substrates by depositing a film that corrects for inherent TTV and / or flatness errors in the substrate. In some embodiments, the starting substrate can be of lower quality that does not meet the flatness / TTV specifications. In some embodiments, the starting substrate can be a substrate with a thickness smaller than currently available substrate thicknesses (e.g., 100 micrometers). In some embodiments, the starting substrate has specifications that meet the desired specifications and achieve substantial improvement after the nP3 process. Because waveguide substrates typically have a refractive index of 1.6 or greater, a sacrificial film can be used to deposit and transfer the contours to the substrate. Alternatively, high-index contouring materials, such as those being developed by companies such as Microresist and NTTAT, can be used as a functional film that is left behind if the refractive index closely matches that of the substrate and if spurious reflections from the interface do not result in substantial loss in light intensity. In some embodiments, flatness / TTV correction may be combined with moth-eye texturing for anti-reflection. In some embodiments, both sides of the substrate may be contoured and have texture.

[0115] High-energy lasers are used in defense applications and require tight control over beam shape to maintain focused laser intensity over extremely long ranges (several kilometers or more). These mirrors are typically fabricated using SiC and Si substrates. The nP3 process for flat substrates with sacrificial films, combined with a sacrificial film etching step, can be used to fabricate optical components with desired profiles. Furthermore, errors in the beam profile of existing laser systems can be corrected, and a single corrector plate can be fabricated that can be placed in the beam path to correct the errors. In one embodiment, the optical component for a high-energy laser system is a flat substrate with peak-to-valley flatness better than lambda / 10. In one embodiment, the optical component for a high-energy laser system is a curved substrate with peak-to-valley deviation from the nominal profile better than lambda / 10. In one embodiment, the optical component for a high-energy laser system is a corrector plate with peak-to-valley deviation from the desired profile better than lambda / 10.

[0116] Metasurfaces and flat lenses are nanopatterned flat substrates that exhibit lens-like behavior due to subwavelength interactions with one or more specific wavelengths of light. Common lens surfaces are typically designed to have spherical phase contours. These incorporate spherical aberrations but minimize off-axis aberrations (e.g., coma). Metalens surfaces are typically designed to have "hyperbolic" phase contours. These incorporate off-axis aberrations (e.g., coma) but minimize spherical aberrations. The presence of these aberrations limits the NA of the metalens. Fabrication tolerances and substrate flatness / TTV can introduce unwanted aberrations. Correction of both aberrations has been implemented simultaneously with multisurface lenses or separate corrector plates. Instead of a separate metalens surface or correction plate, the nP3 process, either using a sacrificial film that is etched or using an index-matching film that is left behind, can be used to either create a low-cost correction plate or contour the back surface of the metalens substrate to provide a one-time correction for all of the following aberrations: systematic aberrations resulting from the phase pattern design, systematic aberrations resulting from off-axis imaging, random aberrations resulting from fabrication errors and tolerances, and random aberrations resulting from substrate non-flatness / TTV.

[0117] In the above situations, textured or patterned profiles may be deposited using a textured or patterned superstrate to impart other functionality, such as anti-reflection. Use of the nP3 process can allow for the following: increased uniformity from substrate to substrate by customizing the nP3 profile based on the aberration profile from the fabricated metalens and substrate combination; increased variety of phase profiles that can be produced from a single nanopattern; relaxed constraints on the design of the metalens; and relaxed process constraints during fabrication of the metalens.

[0118] Other applications in which the nP3 process can be used on flat or curved substrates include substrates for free space optics for next generation long distance communications, substrates for x-ray mirrors, optics for space applications, optics for photolithography tools, and optics for other equipment such as telescopes, microscopes, cameras, inspection machines, etc.

[0119] The description of various embodiments of the present invention has been presented for purposes of illustration and is not intended to be exhaustive or limited to the disclosed embodiments. Many improvements and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein has been selected to best explain the principles, practical applications, or technical improvements of the embodiments to technology found in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein. [Explanation of symbols]

[0120] 100 nP3 device, 101 contouring subsystem, 102 metrology subsystem, 103 linear horizontal stage, tie beam, 104 support table, lateral register actuator, 105 edge sensor, 119 UV-transparent vacuum chuck, 200 contouring subsystem, 201 interleaf / deinterleaf rollers, 202 lateral register module, 203 precision idler roller, 204 voice coil motor (VCM) driven flexible support stage, 205 supply and take-up rollers, 206 drive roller, 207 curing module, 208 inkjet printhead, 209 contouring material, 210 rigid substrate, 211 vacuum pin chuck, 212 large travel stage, large travel direction, 213 nip roller, 300 contouring subsystem, 301 air support, 302 vacuum roller, 400 lateral register correction mechanism, lateral register correction module, 401 Deinterleaf roller, 402 Load cell roller, 403 Unwinding feed roller, linear support, 404 Sensor, unwinding roller, 405 Linear motor, load cell roller, 406 Frame, 500 Superstraight tension control system, 501 Feed and raking roller, 600 Precision alignment system, 601 YZ stage, alignment stage, 602 Self-aligning ball bearing, 701 UV-transparent vacuum chuck, 702 Micrometer knob, 703 Ball end, 704 Micrometer mount, 705 Ball sleeve, 706 Stationary plate, 707 UV lamp, 708 Superstraight web, 709 Substrate, 710 Air cavity, 711 UVT (ultraviolet transparent) acrylic plate, 712 Porous area, 713 Through-hole, vacuum supply, 714 Support, 715 Bottom plate, 801 Actuator, 802 Base plate, 803 Flexible support, 804 translational flexible support, 805 displacement sensor, 806 stationary chassis, 807 voice coil motor, 901 pin, 902 transparent region, 903 embedding ring, 904 vacuum pad, 905 enlarged image of pin, 906 pin, annular vacuum pin chuck, 907 transparent region, central region, 1001 UV transmission chuck, UV transparent chuck, 1002 super straight web, 1003 pin chuckSubstrate chuck, 1004 Metal film, 1101 Inkjet fixture flexible mechanism design, 1102 Fixture body, 1103 Flexible rotational coupling, 1104 Manual actuator, 1200 nP3 metrology subsystem, 1201 Telescopic lens, 1202 Cage mounting hardware, 1203 Mirror, 1204 Stationary reflector, 1205 Substrate and VCM stage location during metrology, 1206 Mounting station, 1207 Optical sensor, 1208 Linear stage, XY stage, 1301 Laser beam, 1302 Laser, 1305, 1306 Kinematic mount, 1400 Automated telescopic system, 1401 Translation stage, 1601 Contoured material, drop pattern, 1602 Substrate, 1603 Inkjet, 1604 Superstrate, 1605 UVT chuck, 1606 UV (ultraviolet) flash, 1607 Continuous film, 1608 VCM stage, 1609 measurement station, 1610 x-stage, 1611 laser beam, 1801 contouring material, drop pattern, 1802 superstrate, 1803 inkjet, 1804 UVT chuck, 1805 substrate, 1806 UV (ultraviolet) flash, 1807 continuous film, 1808 VCM stage, 1809 measurement station, 1810 x-stage, 1811 laser beam

Claims

1. 1. A system for plannable contouring with nanoscale precision, comprising: a contouring module having ink jets for dispensing contouring material; a subsystem comprising a vacuum chuck and a vertical-tip-tilt stage, wherein intermittent movement of the vacuum chuck and the vertical-tip-tilt stage is used to form a continuous film of the contouring material between a superstrate and a substrate; a subsystem for curing the contouring material; a metrology module for performing optical metrology at every point on the substrate; A system comprising:

2. The system of claim 1 , wherein the contouring module further comprises a subsystem for aligning the superstrate with the substrate.

3. The system of claim 1 , wherein the contouring module further comprises a subsystem for mitigating air bubbles when forming a continuous film of the contouring material between the superstrate and the substrate.

4. The system of claim 1 , wherein the superstrate has a textured or patterned portion.

5. The system of claim 1 , wherein the substrate is secured to a translating chuck in a stage between the contouring module and the metrology module.

6. The system of claim 1 , wherein the subsystem for curing the contouring material comprises an ultraviolet-transparent vacuum chuck.

7. The system of claim 1 , wherein the metrology module comprises one or more of the following: a Shack-Hartmann wavefront sensor, an interferometer, an optical profilometer, a reflectometer, and a spectrophotometer.

8. The system of claim 1 , wherein the system is used to contour precision optical components.

9. The system of claim 1 , wherein the system is used to correct flatness or total thickness variation (TTV) errors in a substrate.

10. The system of claim 1 , wherein the system is used to contour ophthalmic or trial lenses.

11. 10. The system of claim 1, further comprising a module for communication, data transfer, and data exchange with one of the following: a local computer, a remote computer, a cloud-based data center, and a cloud-based workstation.

12. The system of claim 1 , wherein the contouring material dispense location is determined using an algorithm executed in one of the following locations: a local computer, a remote computer, and a cloud-based computer.

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