Adjustable mounting device for optical elements

Abstract

An optical system in a pulse stretcher of a deep ultraviolet light source. The optical system includes: optical elements configured in operation along a path of a light beam generated by the deep ultraviolet light source; and an adjustable mounting device to which the optical elements are positioned. The adjustable mounting device includes: a passive alignment mount, and a drive mechanism coupled to the passive alignment mount, the drive mechanism including a rotationally constrained wedge.

Description

Cross-references to related applications

[0001] This application claims priority to U.S. Application No. 63 / 571,516, filed March 29, 2024, entitled “Adjustable Mounting Apparatus for Optical Elements,” which is incorporated herein by reference in its entirety. Technical Field

[0002] The subject of this disclosure relates to adjustable mounting arrangements for optical elements in optical pulse stretcher devices for deep ultraviolet light sources. Background Technology

[0003] A photolithography apparatus is a machine that applies a desired pattern to a substrate, typically a target portion of the substrate. For example, photolithography apparatuses can be used in the fabrication of integrated circuits (ICs). In this case, a patterning device (which may also be referred to as a mask or stencil) can be used to generate a circuit pattern to be formed on an individual layer of the integrated circuit (IC). This pattern can then be transferred onto a target portion (e.g., a portion comprising one or more dies) on a substrate (e.g., a silicon wafer). The transfer of the pattern is typically via imaging on a layer of radiation-sensitive material (resist) disposed on the substrate. Generally, a single substrate will comprise a network of continuously patterned adjacent target portions. Known photolithography apparatuses include: so-called steppers, in which each target portion is irradiated by exposing the entire pattern to the target portion at once; and so-called scanners, in which each target portion is irradiated by scanning the pattern in a given direction (“scan”-direction) with a radiation beam, while simultaneously scanning the target portion parallel or antiparallel to this scan direction. A pattern can also be transferred from a patterning device to a substrate by imprinting the pattern onto the substrate.

[0004] For example, a light (or laser) source can be used to generate spectral radiation for illuminating a pattern-forming apparatus using a photolithography device. The laser source may include a high-power gas discharge laser system and an optical pulse stretcher configured to extend the pulses of the high-power gas discharge laser system's output. Summary of the Invention

[0005] In some general aspects, the optical system is located within a pulse stretcher of a deep ultraviolet light source. The optical system includes: optical elements configured in operation along the beam path generated by the deep ultraviolet light source; and an adjustable mounting device to which the optical elements are positioned. The adjustable mounting device includes: a passive alignment mount and a drive mechanism coupled to the passive alignment mount, the drive mechanism including a rotationally constrained wedge.

[0006] The implementation may include one or more of the following features. For example, the optical element may be a reflective optical element, a partially reflective beam splitter, a diffractive optical element, or a refractive optical element. The passive alignment mount may include a kinematic mount or a pseudo-kinematic mount.

[0007] A passive alignment mount may include a kinematic mount. The kinematic mount may include a flat surface, a groove, and a recess. The drive mechanism may include a first rounded tip abutting the flat surface, a second rounded tip abutting the groove, and a third rounded tip abutting the recess. The first rounded tip abutting the flat surface provides five degrees of freedom, the second rounded tip abutting the groove provides four degrees of freedom, and the third rounded tip abutting the recess provides three degrees of freedom. The kinematic mount may include a first groove defined along a first axial direction, a second groove defined along a second axial direction, and a third groove defined along a third axial direction, each axial direction being different from the other two axial directions.

[0008] The passive alignment mount can be positioned and aligned to the optical element unit that houses the optical element.

[0009] The drive mechanism may include multiple drive systems, each associated with a contact element of the passive alignment mount. At least one drive system may include: a pin with a rounded tip at a first end and a wedge at a second end, the rounded tip abutting against one of the contact elements of the passive alignment mount; and a rod including a spherical tip constrained by the wedge of the pin. The optical system may also include a structure defining a plurality of cylindrical openings, each cylindrical opening receiving a pin or rod. The structure may constrain and guide each pin and each rod received within its respective cylindrical opening. Translation of the rod in a first direction may cause the spherical tip of the rod to translate in the first direction, the spherical tip abutting against the wedge and causing the pin to translate in a second direction different from the first direction. The second direction may be perpendicular to the first direction. The passive alignment mount may include a kinematic mount, and the contact element of the kinematic mount may be one of the following elements: a flat surface, a recess, or a groove. The rod of each drive system may be adjustable from the outside of the housing housing containing the optical element.

[0010] The drive mechanism may include three drive systems, each associated with a contact element of the passive alignment mount. One drive system can provide a linearly constrained fixed point at the corresponding contact element, and the other two drive systems can be configured to move or translate the corresponding contact element.

[0011] The passive alignment mount may include multiple contact elements, each of which may include or be made of hardened stainless steel. The drive mechanism may include multiple drive systems. Each drive system may be associated with a contact element of the passive alignment mount. At least two of the drive systems may include a wedge and a rounded tip. Both the wedge and the rounded tip may be made of a hardened material with a hardness greater than or equal to 1400 N / mm². Both the wedge and the rounded tip may be made of a hardened material with a hardness greater than or equal to 2075 N / mm². The wedge and the rounded tip may be made of hardened stainless steel. Each wedge and each rounded tip may include a polished surface finish with a roughness of Ra 0.8 micrometers (Ra 32 microinches, 35 RMS) or less. Each wedge and each rounded tip may include a polished surface finish with a roughness of Ra 0.4 micrometers (Ra 16 microinches, 17.6 RMS) or better.

[0012] Adjustable mounting devices may be lubricant-free.

[0013] The optical element may be a first optical element, and the adjustable mounting device may be a first adjustable mounting device to which the first optical element is positioned. The first adjustable mounting device may include a first kinematic mount and a first wedge adjustment mechanism coupled to the first kinematic mount. The optical system may also include a second optical element arranged relative to the first optical element, and a second adjustable mounting device to which the second optical element is positioned. The second adjustable mounting device may include a second kinematic mount and a second wedge adjustment mechanism coupled to the second kinematic mount.

[0014] The wedge may include a flat surface at the end of the pin. The pin may extend along the axial pin direction, and the normal to the flat surface extends between 20° and 40° relative to the axial pin direction. The drive mechanism may include a wing extending from the pin and adjacent to the end of the flat surface of the wedge. The wing may provide rotational constraint on the wedge.

[0015] The adjustable mounting device can be configured to achieve tilt adjustment of the optical elements in pitch and roll.

[0016] In another overall aspect, the optical system is located within the pulse stretcher of the deep ultraviolet light source. The optical system includes: a pair of folding mirrors configured in operation along the path of the beam generated by the deep ultraviolet light source to guide the beam from a first portion of the pulse stretcher to a second portion; a pair of mirror units mounted to the structure, each folding mirror remaining stable within its respective mirror unit; and a pair of adjustable mounting devices. Each mirror unit is positioned at a corresponding adjustable mounting device. Each adjustable mounting device includes a passive alignment mount associated with each mirror unit and a drive mechanism associated with each passive alignment mount. The drive mechanism includes a rotationally constrained wedge.

[0017] Implementations may include one or more of the following features. For example, the adjustable mounting device may be configured to achieve tilt adjustment in pitch and roll of a folding mirror that remains stable in a mirror unit positioned at the adjustable mounting device.

[0018] In another overall aspect, the optical elements of the pulse stretcher are positioned at an adjustable mounting device. The adjustable mounting device is arranged within a controlled environment of the pulse stretcher housing. The adjustable mounting device includes: a unit to which the optical elements are positioned; a passive alignment mount associated with the unit; and a drive mechanism coupled to the passive alignment mount. At least a portion of the drive mechanism is controllable from outside the pulse stretcher housing. The drive mechanism includes a rotationally constrained wedge.

[0019] Details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features will become more apparent from the specification, drawings, and claims. Attached Figure Description

[0020] The accompanying drawings (which are incorporated herein and form part of the specification) illustrate this disclosure and, together with the description, further assist in explaining the principles of this disclosure and enable those skilled in the art to make and use the aspects described herein.

[0021] Figure 1 This is a schematic diagram of an optical system positioned at an adjustable mounting device, which includes a passive alignment mount and a drive mechanism mechanically coupled to the passive alignment mount, the drive mechanism including a rotationally constrained wedge.

[0022] Figure 2This is a schematic diagram of an implementation of an adjustable mounting device, which includes a passive alignment mount having multiple contact elements and a drive mechanism having multiple drive systems, wherein each drive system is associated with a corresponding contact element, and at least two of the drive systems each include a corresponding rotationally constrained wedge.

[0023] Figure 3A It is a perspective view of an embodiment of an adjustable mounting device, which includes a passive alignment mount with three contact elements and a drive mechanism with three drive systems, wherein each drive system is associated with a corresponding contact element, and at least two of the drive systems each include a corresponding rotationally constrained wedge.

[0024] Figure 3B It has three contact elements. Figure 3A A perspective view of the passive alignment mount;

[0025] Figure 4 yes Figure 3A Side plan view of the adjustable mounting device;

[0026] Figure 5A It is the section taken along line 5A-5A. Figure 4 Cross-sectional view of the adjustable mounting device;

[0027] Figure 5B It is the section taken along line 5B-5B. Figure 4 Cross-sectional view of the adjustable mounting device;

[0028] Figure 6A It is a side perspective view of an embodiment of a pin that can be used in the drive mechanism of an adjustable mounting device;

[0029] Figure 6B yes Figure 6A Side plan view of the pin;

[0030] Figure 6C yes Figure 6A Side plan view of the pin;

[0031] Figure 6D yes Figure 6A Side cross-sectional view of the center pin;

[0032] Figure 7A It is a side perspective view of an embodiment of a rod that can be used in the drive mechanism of an adjustable mounting device;

[0033] Figure 7B yes Figure 7A Side section view of the middle rod;

[0034] Figure 8This is a block diagram of an implementation of an optical pulse stretcher positioned at the output of a light source, the optical pulse stretcher accommodating one or more optical systems;

[0035] Figure 9A This is a block diagram of an implementation of an optical pulse stretcher that incorporates one or more optical systems;

[0036] Figure 9B yes Figure 9A A block diagram of a portion of an optical pulse stretcher shows a set of mirrors, each positioned at an adjustable mounting and controlled by the adjustable mounting; and

[0037] Figure 10 This is a perspective view of an embodiment of an adjustable mounting device, which includes a passive alignment mount with three contact elements and a drive mechanism with three drive systems, each drive system being associated with a corresponding contact element, and each of the three drive systems including a corresponding rotationally constrained wedge.

[0038] The features of this disclosure will become more apparent when viewed in conjunction with the accompanying drawings (in which the same reference numerals identify corresponding elements throughout). In the drawings, similar reference numerals generally denote the same, functionally similar, and / or structurally similar elements. Furthermore, the leftmost numeral of the reference numerals generally identifies the drawing in which that reference numeral first appears. Unless otherwise stated, the figures provided throughout this disclosure should not be construed as toll-free. Detailed Implementation

[0039] refer to Figure 1 Optical system 100 is arranged in an optical pulse stretcher 170 associated with a light source 160, which may be a deep ultraviolet light source. Optical system 100 includes optical elements 105 arranged or configured along the path of a beam 162 generated by the light source 160 during operation. Beam 162 may be a pulsed beam input to optical pulse stretcher 170 but not yet interacting with any other optical elements within optical pulse stretcher 170. Alternatively, beam 162 may be a pulsed beam that has already interacted with one or more other optical elements within optical pulse stretcher 170. For clarity, Figure 1 The optical pulse stretcher 170 in the diagram does not show other components such as other optical elements. The implementation of the optical pulse stretcher 170 is described in... Figure 8 , Figure 9A and Figure 9B It is shown in the middle.

[0040] The optical pulse stretcher 170 is defined within a hermetically sealed housing or enclosure 171, which includes one or more walls defining an inner cavity 173. Figure 1 The housing 171 is schematically depicted as 172 in a two-dimensional representation. The housing 171 can be any suitable three-dimensional shape, such as a rectangular prism, cube, or cylinder, and the number of walls 172 can vary depending on the shape. During operation of the optical pulse stretcher 170, the cavity 173 is maintained as a controlled environment. For example, the cavity 173 can be formed by hermetically sealed walls 172. In this way, the cavity 173 can be maintained at a specific pressure (such as pressure below or above atmospheric pressure) or at a specific humidity level (such as a low humidity environment). As another example, the cavity 173 can be configured as a gas-purged environment (such as a nitrogen-purged environment). In some embodiments, the cavity 173 is maintained at a pressure approximately 4 to 8 pounds per square inch (psi) above atmospheric pressure. For example, if the cavity 173 is a gas-purged environment, the pressure can be maintained at approximately 18 to 23 psi. The optical pulse stretcher 170 is configured to receive an input pulse beam 161 and generate at least one stretched output pulse beam 163.

[0041] The optical element 105 within the optical pulse stretcher 170 needs to be adjusted (e.g., aligned or modified in position or angle). For example, to ensure that the beam 162 is properly aligned and passes through an optical element optically downstream of the optical system 100, the optical element 105 may need to be translated along or rotated about one or more local axes. The local coordinate system of the optical element 105 is defined by the X... 105 Y 105 Z 105 As given. Furthermore, such adjustment of the optical element 105 can occur when the beam 162 interacts with the optical element 105. For this purpose, the optical system 100 includes an adjustable mounting device 110 in which the optical element 105 is positioned (e.g., fixed or constrained). The adjustable mounting device 110 achieves alignment of the beam 162 relative to an optical element downstream of the optical element 105. The adjustable mounting device 110 includes a passive alignment mount 120 and a drive mechanism 130 mechanically coupled to the passive alignment mount 120. The passive alignment mount 120 receives the optical element 105, while the drive mechanism 130 transmits mechanical constraints and / or motion to the passive alignment mount 120 and the optical element 105. The combination of the passive alignment mount 120 and the drive mechanism 130 provides a yaw / tilt mechanism that achieves adjustment of the pitch and / or roll (relative to X) of the optical element 105. 105 axis or Y 105The adjustable mounting device 110 allows the optical element 105 to be adjusted without disturbing the controlled environment within the cavity 173. That is, the adjustable mounting device 110 allows the optical element 105 to be adjusted without opening the hermetically sealed housing 171.

[0042] The adjustable mounting device 110 is adapted to a small coverage area (or volume) available within the cavity 173 of the optical pulse stretcher 170. The adjustable mounting device 110 is designed to reduce friction at certain mechanical interfaces within the adjustable mounting device 110. For example, the adjustable mounting device 110 uses a set of materials with reduced roughness at the mechanical interfaces to reduce friction at these interfaces. As another example, the mechanical interfaces within the adjustable mounting device 110 are designed in a manner that induces predictable movement at the interfaces. Due to these design improvements, the need for lubricant at the mechanical interfaces within the adjustable mounting device 110 is reduced or eliminated. Lubricant within the cavity 173 is a contaminant and can degrade and diffuse within the cavity 173, and even outside the cavity 173, thereby diffusing into the components of the light source 160. Therefore, by eliminating lubricant within the adjustable mounting device 110, the cavity 173 remains clean or cleaner, and the risk of contaminating the light source 160 is reduced.

[0043] The features of the adjustable mounting device 110, which achieves reduced friction, are described below. As previously mentioned, the adjustable mounting device 110 includes a passive alignment mount 120 and a drive mechanism 130 mechanically coupled to the passive alignment mount 120. The drive mechanism 130 includes a wedge 135 that is a generally flat and rigid surface. The wedge 135 is subject to a rotational constraint 136, as will be discussed in detail below. The rotational constraint 136 applied to the wedge 135 causes predictable movement within the drive mechanism 130 and between the drive mechanism 130 and the passive alignment mount 120.

[0044] Optical element 105 can be any element configured to optically interact with beam 162. For example, optical element 105 can be a reflective optical element (such as a mirror), a partially reflective optical element (such as a beam splitter), a diffractive optical element (such as a diffraction grating), or a refractive optical element (such as a prism).

[0045] As mentioned earlier, optical element 105 needs to be positioned in three dimensions (X-axis). 105 Y 105 Z 105In this context, the components are distributed within a spatial volume and have three specified and / or controlled rotations. The passive alignment mount 120 may include a kinematic mount or a pseudo-kinematic mount, or a part of a kinematic mount or a pseudo-kinematic mount. The adjustable mount 110 achieves high precision in orienting the optical element 105 relative to another body within the cavity 173 by providing precise mating features between the optical element (passive alignment mount 120) and the connecting elements of the drive mechanism 130, and precise distances between these features on the passive alignment mount 120 and the connecting elements of the drive mechanism 130.

[0046] In some implementations, such as Figure 2 As shown, the optical system 200 includes an adjustable mounting device 210 designed to have a passive alignment mount 220 and a drive mechanism 230. The optical system 200 also includes an optical element 205, which, as discussed above, can be any element (similar to optical element 105) configured to optically interact with the beam 262. The passive alignment mount 220 includes a plurality of contact elements 220A, 220B, 220C, and the drive mechanism 230 includes a plurality of drive systems 230A, 230B, 230C, each drive system 230A, 230B, 230C associated with a corresponding and specific contact element 220A, 220B, 220C. Drive systems 230A and 230C each include corresponding wedges 235A and 235C, and each wedge 235A, 235C is subject to rotational constraints 236A, 236C, as will be discussed in detail below.

[0047] In this embodiment, three contact elements 220A, 220B, 220C and three drive systems 230A, 230B, 230C are shown, but in other embodiments there may be fewer or more than three. Furthermore, although... Figure 2 The schematic diagram is represented in two dimensions, i.e., X. 205 Z 205 However, it should be understood that the optical system 200 extends along three dimensions, including along the Y-axis. 205 The axis extends both inside and outside the page. Therefore, contact elements 220A, 220B, and 220C can be arranged, for example, in the X... 205 Y 205 In the spatial arrangement of surfaces, and can be along Z 205 Shaft extension. Drive systems 230A, 230B, and 230C can also be arranged along the X-axis. 205 Y 205 Z 205One or more shafts extend from the shaft. Furthermore, each contact element 220A, 220B, 220C is positioned differently from the other contact elements 220A, 220B, 220C, such that no contact element abuts against each other. Similarly, each drive system 230A, 230B, 230C is located in a spatial position that does not intersect or abut against any other drive system among the other drive systems 230A, 230B, 230C.

[0048] As previously stated, the alignment mount 220 is “passive,” meaning that proper alignment is achieved when the contact elements 220A, 220B, 220C engage with the ends of the corresponding drive systems 230A, 230B, 230C. In some cases, the engagement of these mating features permanently controls the alignment.

[0049] The contact elements 220A, 220B, 220C of the passive alignment mount 220 and the drive systems 230A, 230B, 230C of the drive mechanism 230 can be microprocessed. The contact elements 220A, 220B, 220C of the passive alignment mount 220 can be positioned and aligned with the optical element unit 221 housing the optical element 105. The contact elements 220A, 220B, 220C are fixed to the unit 221 such that movement transmitted to a particular contact element causes a corresponding movement to be transmitted to the unit 221 at the position of that contact element. Furthermore, the drive systems 230A, 230B, 230C of the drive mechanism 230 can be constrained within the structure or body 231. That is, structure 231 may define a plurality of openings 231A, 231B, 231C, wherein each opening 231A, 231B, 231C receives at least a portion of the drive system of the corresponding drive system 230A, 230B, 230C.

[0050] As described above, the passive alignment mount 220 may include a kinematic mount or a pseudo-kinematic mount, or a part of a kinematic mount or a pseudo-kinematic mount. A kinematic mount is formed between the passive alignment mount 220 and the drive mechanism 230, thereby creating stiffness between the two bodies (optical element 105 and drive mechanism 230) in six (and only six) independent degrees of freedom (“DOF”) or directions. Six DOFs are desired because the position of any object in space is defined by three orthogonal coordinates, and the orientation of an object is defined by three orthogonal rotations. Kinematic mounts such as this one have the advantage of stiffness; however, any strain or deformation in the drive mechanism 230 is not communicated to the passive alignment mount 220 (or the optical element 105). Therefore, if the drive mechanism 230 undergoes deformation due to applied load or overall temperature variation, any sensitive optical alignment of the optical element 105 is not altered in the passive alignment mount 220.

[0051] In some implementations, it is desirable to customize the degrees of freedom based on the configuration of “pseudo-kinematics” supports or mounts. “Pseudo-kinematics” means that although there may be many DOFs connecting at least two bodies (optical element 105 and drive mechanism 230), in the actual assembly scheme, the DOFs can be customized such that only six DOFs have relatively high stiffness, while essentially all other degrees of freedom have relatively low stiffness.

[0052] Therefore, true "kinematic" support means that there are only six stiff DOFs connecting the two components, and no other stiffness paths exist. "Pseudo-kinematic" support means that there are six DOFs with relatively high stiffness, and possibly many more DOFs with much lower stiffness (typically two to three orders of magnitude lower). In some applications, it is desirable for pseudo-kinematic DOFs with relatively low stiffness to be two to three orders of magnitude less stiff than DOFs with relatively high stiffness.

[0053] The materials forming the passive alignment mount 220 and drive mechanism 230 of the kinematic (or pseudo-kinematic) mount are provided with polished surfaces having a surface roughness of Ra 0.8 micrometers (µm) or better. For example, the roughness can be approximately 0.8, 0.6, 0.5, 0.4, 0.3, 0.2 micrometers (µm) or less. Furthermore, the materials forming the passive alignment mount 220 and drive mechanism 230 of the kinematic (or pseudo-kinematic) mount can have a hardness greater than or equal to 1400 Newtons per square millimeter (N / mm²). 2 It is made of a hardened material. For example, the hardness can be approximately 1400, 1625, 1850, 2075, 2300 or greater than 2300 N / mm. 2In one example, the passive alignment mount 220 and drive mechanism 230 used to form the kinematic (or pseudo-kinematic) mount are made of hardened stainless steel. Although the average roughness (Ra) is a useful average value, various roughness distributions can still have the same average roughness value.

[0054] Due to these design improvements, the need for lubricant at the mechanical interfaces between the corresponding contact elements 220A, 220B, 220C of the passive alignment mount 220 and the drive systems 230A, 230B, 230C of the drive mechanism 230 is eliminated. In this way, lubricant within the adjustable mounting device 210 is also eliminated.

[0055] refer to Figure 3A , Figure 3B and Figure 4 The optical system 300 is configured for use within the cavity 173 of the housing 171 and is part of the optical pulse stretcher 170 (e.g., Figure 1 (As shown). Therefore, the optical system 300 along, such as Figure 1 Beam 162 or Figure 2 The beam paths, such as beam 262, are configured. The optical system 300 includes optical elements 305 (in which optical element unit 321 houses or holds optical elements 305) Figure 3A and Figure 3B Invisible in the middle, but in Figure 4 , Figure 5A and Figure 5B (shown in the image), and an adjustable mounting device 310 designed based on the principle of adjustable mounting device 110 or 210.

[0056] The adjustable mounting device 310 realizes beam 162 or beam 262 ( Figure 2 (Or Figure 3) Alignment with an optical element downstream of optical element 305 in optical pulse stretcher 170. Adjustable mounting device 310 includes a passive alignment mount 320 positioned on and aligned with optical element unit 321 housing optical element 305. For example, optical element 305 can be securely mechanically mounted to optical element unit 321. Adjustable mounting device 310 includes a drive mechanism 330 mechanically coupled to passive alignment mount 320, which is constrained by a solid structure or body 331. Drive mechanism 330 transmits mechanical constraint and / or motion to passive alignment mount 320 and optical element 305. In this way, passive alignment mount 120 and drive mechanism 330 combined provide alignment of optical element 305 (relative to X) 305 axis or Y 305 The yaw and / or tilting mechanism of the optical system 300 is adjusted without disturbing the cavity 173 configured with the optical system 300. Figure 1A controlled environment within.

[0057] As described above, optical element 305 may be a reflective optical element (such as a mirror), a partially reflective optical element (such as a beam splitter), a diffractive optical element (such as a diffraction grating), or a refractive optical element (such as a prism). For optical element 305 that relies on transmission through optical element 305, optical element unit 321 may include opening 322, and structure 331 may include openings through which light can pass.

[0058] The passive alignment mount 320 includes three contact elements 320A, 320B, and 320C, and the drive mechanism 330 includes three drive systems 330A, 330B, and 330C, wherein each drive system 330A, 330B, and 330C is associated with a corresponding and specific contact element 320A, 320B, and 320C.

[0059] In addition to the passive alignment mount 320 directly coupled to the optical element unit 321, the adjustable mounting device 310 also includes a spring mounting device 312 comprising a pair of spring element systems 313D, 313E, which are fixed to the passive alignment mount 320 at corresponding first ends 314D, 314E and to the optical element unit 321 at corresponding second ends 315D, 315E. In this way, the optical element unit 321 is held in position relative to the passive alignment mount 320, but can be moved under the control of the drive systems 330A, 330B, 330C and the corresponding contact elements 320A, 320B, 320C.

[0060] The passive alignment mount 320 can be part of a kinematic mount or a pseudo-kinematic mount. That is, the kinematic mount (or pseudo-kinematic mount) is formed between the passive alignment mount 320 and the drive mechanism 330, thereby creating stiffness in six independent degrees of freedom (DOF) or directions between the two bodies (optical element 305 and drive mechanism 330).

[0061] In this embodiment, the kinematic mount includes three contact elements 320A, 320B, and 320C, each with a different design. Figure 3B An exploded view is shown, in which contact elements 320A, 320B, and 320C are shown separated from optical element unit 321. Contact element 320A is a flat surface, contact element 320B is a recess (or curved surface), and contact element 320C is a groove. Contact element 320A is a flat surface at the end of the contact body, the flat surface being in the X... 305 Y 305In-plane extension. The socket or curved surface of contact element 320B along +Z... 305 The direction gradually narrows into the contact body. Contact element 320C is a groove or linear indentation defined in the contact body.

[0062] Accordingly ( Figure 5A and Figure 5B Each drive system 330A and 330C includes corresponding wedges 335A and 335C, and each wedge is subject to rotational constraints 336A and 336C. Figure 5A and Figure 5B (This will be discussed in detail below.)

[0063] As previously stated, the alignment mount 320 is "passive," meaning that correct alignment can be achieved by operating the drive systems when the contact elements 320A, 320B, 320C engage with the ends of the corresponding drive systems 330A, 330B, 330C. In some cases, the engagement of these mating features permanently controls the alignment.

[0064] Same reference Figure 5A and Figure 5B The drive systems 330A, 330B, and 330C of the drive mechanism 330 are constrained within the structure 331.

[0065] Drive system 330B ( Figure 5B The device includes a pin 340B extending through an opening 331B defined in structure 331. The pin 340B includes a rounded tip 341B at a first end, and is secured in or to structure 331 at a second end. The rounded tip 341B abuts against a contact element 320B, which, as discussed above, is a recess. Specifically, the tip 341B is positioned within the recess of the contact element 320B. In this way, three rotational degrees of freedom exist at the interface between the rounded tip 341B and the contact element 320B.

[0066] Drive system 330A ( Figure 5A The pin 340A includes a rounded tip 341A at a first end and a wedge 335A at a second end. The pin 340A extends through an opening 331A1 defined in the structure 331, and by using a biasing device 344A (e.g., a spring), the pin 340A is positioned at -Z 305The direction is biased away from the contact element 320A. The drive system 330A also includes a rod 342A extending through an opening 331A2 defined in the structure 331. The opening 331A2 intersects the opening 331A1 at the point where the rod 342A mates with the pin 340A. The rod 342A includes a spherical tip 343A of the wedge 335A of the contact pin 340A. The rod 342A is configured to move along the X direction when an external force is applied. 305 The axis translates linearly within opening 331A2, and along +Z. 305 The direction will be reversed to provide a reverse bias to pin 340A to maintain contact between the round tip 341A and the contact element 320A. An external force can be applied to position 346A of rod 342A, and this external force can be applied from outside the structure 331, or even from outside the housing 171 that houses the optical element 105. Figure 1 The rotational degree of freedom is applied. Because the contact element 320A is a flat surface, there are three rotational degrees of freedom and two translational degrees of freedom at the interface between the round tip 341A and the contact element 320A.

[0067] The tip 343A is constrained 336A by the wedge 335A of the pin 340A (and constrained 336A at the wedge 335A of the pin 340A), which improves the predictability of movement between the rod 342A and the pin 340A. Specifically, the pin 340A also includes a wing 345A extending from the second end of the pin 340A (as shown in the image). Figures 6A to 6D (As shown more clearly in the image), the edge of the flat surface of the wing 345A is adjacent to that of the wedge 335A. The wing 345A acts as a stop to reduce the impact of the tip 343A along the Y-axis. 305 Axis (perpendicular to X) 305 Translation of the axis of the shaft, and to reduce the wedge 335A and pin 340A around Z. 305 Rotation of the axis.

[0068] Rod 342A along -X 305 The directional translation causes the tip 343A to move along -X 305 Directional translation. Furthermore, because pin 340A is typically constrained to move only along the Z-axis. 305 The axis is translated, so the tip 343A moves along +Z at the interface with the wedge 335A. 305 Directional push pin 340A. Round tip 341A abuts against contact element 320A, which is a flat surface, as discussed above. Pin 340A moves along +Z... 305 The movement in the direction causes the tip 341A to move along +Z. 305 Directional translation contact element 320A. Alternatively, rod 342A along +X... 305 The directional translation causes the tip 343A to move along +X. 305 Directional translation. Furthermore, because pin 340A is typically constrained to move only along the Z-axis.305 The axis translates, and pin 340A is biased away from contact element 320A, so tip 343A is positioned along –Z at the interface with wedge 335A. 305 Directional release pin 340A. As long as the tip 343A does not move too far to disengage from the wedge 335A, the round tip 341A remains in contact with or abuts against the contact element 320A. Pin 340A along –Z 305 The movement in the direction causes the tip 341A to move along –Z 305 Directional translation contact element 320A.

[0069] Drive system 330C ( Figure 5B The pin 340C includes a rounded tip 341C at a first end and a wedge 335C at a second end. The pin 340C extends through an opening 331C1 defined in the structure 331, and by using a biasing device 344C (such as, for example, a spring), the pin 340C is positioned at -Z... 305 The direction is biased away from the contact element 320C. The drive system 330C also includes a rod 342C extending through an opening 331C2 defined in the structure 331. The opening 331C2 intersects the opening 331C1 at the point where the rod 342C mates with the pin 340C. The rod 342C includes a spherical tip 343C of the wedge 335C of the contact pin 340C. The rod 342C is configured to move along the X direction when an external force is applied. 305 The axis translates linearly within opening 331C2, and along +Z. 305 The direction will be reversed to provide a bias to pin 340C to maintain contact between the round tip 341C and the contact element 320C. An external force can be applied to position 346C of rod 342C, and this external force can be applied from outside the structure 331, or even from outside the housing 171 that houses the optical element 105. Figure 1 The rotational degree of freedom is applied. Because the contact element 320C is a linear groove, there are three rotational degrees of freedom and one translational degree of freedom at the interface between the round tip 341C and the contact element 320C. The translational degree of freedom is in a direction parallel to the groove direction.

[0070] The tip 343C of rod 342C is constrained 336C by the wedge 335C of pin 340C (and constrained 336C at the wedge 335C of pin 340C), which improves the predictability of movement between rod 342C and pin 340C. Specifically, pin 340C also includes a wing 345C extending from a second end of pin 340C (as shown in the image). Figures 6A to 6D (As shown more clearly in the image), the edge of the flat surface of the wing 345C is adjacent to that of the wedge 335C. The wing 345C acts as a stop to reduce the impact of the tip 343C along the Y-axis. 305 Axis (perpendicular to X) 305Translation of the axis of the shaft, and to reduce the wedge 335C and pin 340C around Z. 305 Rotation of the axis relative to rod 342C.

[0071] Rod 342C along -X 305 The directional translation causes the tip 343C to move along -X 305 Directional translation. Furthermore, because pin 340C is typically constrained to move only along the Z-axis. 305 The axis is translated, so the tip 343C moves along +Z at the interface with the wedge 335C. 305 Directional push pin 340C. Round tip 341C abuts against contact element 320C, which is a groove, as discussed above. Pin 340C moves along +Z... 305 The movement in the direction causes the tip 341C to move along +Z. 305 Directional translation contact element 320C. Alternatively, rod 342C along +X... 305 The directional translation causes the tip 343C to move along +X. 305 Directional translation. Furthermore, because pin 340C is typically constrained to move only along the Z-axis. 305 The axis translates, and pin 340C is biased away from contact element 320C, so tip 343C is positioned along –Z at the interface with wedge 335C. 305 Directional release pin 340C. Only tip 343C along -X 305 The pin 341C does not move too far to disengage from the wedge 335C, thus maintaining contact or abutment with the contact element 320C. 305 The movement in the direction causes the tip 341C to move along –Z 305 Directional translation contact element 320C.

[0072] refer to Figures 6A to 6D Examples of pins 640, which can be used as pins 340A or 340C, are shown. Pins 640 are shown with a specific set of geometric dimensions, but these dimensions can be modified depending on the placement of the pin 640 in the structure and the interaction between the pin 640 and its corresponding contact element. Each pin 640 includes a generally cylindrical body 647 extending axially along a pin shaft 640a, which, when the pin 640 operates as a drive mechanism 130, 230, 330, interacts with the Z-axis of the mounting devices 110, 210, 310. 305Axial alignment. Pin 640 includes a rounded tip 641 at a first end and a wedge 635 at a second end. Wedge 635 is a generally flat surface angled relative to axis 640a. For example, the normal 635N of the flat surface of wedge 635 may form an angle θ635 between 20° and 40° with the axial pin axis 640a. When pin 640 is operated in drive mechanisms 130, 230, 330 and the tip of the rod contacts wedge 635, wedge 635 acts to restrain the rod tip and pin 640. For this purpose, pin 640 includes wings 645i, 645ii on the flat surface end flanks of wedge 635.

[0073] refer to Figure 7A and Figure 7B Examples of rod 742 that can be used as rod 342A or rod 342C are shown in Figure 5A and Figure 5B As shown in the diagram, the rod 742 comprises a generally cylindrical body extending along an axial rod axis 742a. ​​When operating as drive mechanisms 130, 230, and 330, this rod 742 interacts with the X-axis of mounting devices 110, 210, and 310. 305 Axis alignment. The rod 742 is a generally rigid body that can be made of a non-interacting material. The rod 742 includes a spherical tip 743 that contacts pin 640 when the rod 742 is operated in drive mechanisms 130, 230, 330. Figures 6A to 6D ) wedge 635.

[0074] The wedge 635 of pin 640 and the tip 743 of rod 742 can be made of a hardened material and can be manufactured sufficiently smooth to reduce friction at the interface between the tip 743 and the surface of wedge 635. This improves the predictability of the movement of pin 640 and eliminates or reduces the need for lubricant at the interface. In some embodiments, the wedge 635 and tip 743 are made of a material with a hardening factor greater than or equal to 1400 N / mm². 2 The surface roughness is made of a hardened material with a hardness of Ra 0.8 micrometers (µm). In one embodiment, the wedge 635 and the tip 743 are made of hardened stainless steel. In some embodiments, the surfaces of the wedge 635 and the tip 743 are polished to have a roughness of Ra 0.8 micrometers (µm) or better. In various embodiments of the mounting, one or more contact elements or contact surfaces may be made of hardened stainless steel, another metallic material, silicon dioxide, another glass material, sapphire, or another mineral material. The Ra value is measured over a specific sampling length as the arithmetic mean of the peaks and troughs of the metallic surface (the surfaces of the wedge 635 and the tip 743), including deviations from the average line. Surface roughness can be measured using a profilometer or a laser scanner. The greater the deviation in the surface, the rougher the surface, and if the Ra value is small, the surface is smooth.

[0075] See Figure 8 An optical pulse stretcher 870 is configured relative to a light source 860. The optical pulse stretcher 870 is positioned at the output of the light source 860. The optical pulse stretcher 870 is designed based on the design principles of the optical pulse stretcher 170, as will be discussed in more detail below in relation to other features of the light source 860 and the optical pulse stretcher 870.

[0076] Light source 860 can be used as part of a photolithography apparatus to provide pulsed light beam 863 to a photolithography exposure apparatus 850 for generating circuit patterns on target portions of a substrate (or wafer). In some embodiments, light source 860 is a deep ultraviolet (DUV) light source, and the beam 863 has a wavelength within the DUV wavelength range, which may include, for example, wavelengths from about 100 nanometers (nm) to about 400 nm. Figure 8 As shown, the light source 860 can be a dual-stage light source including a first stage 864A and a second stage 864B. The first stage 864A may include a master oscillator (MO) that generates a first pulse beam 865, which is transmitted to the second stage 864B via an optical element 866 including relay optics. The second stage 864B may include a power amplifier (PA) that receives the first pulse beam 865 and optically amplifies it to form a second pulse beam 867, which forms an input beam 861 that is guided to an optical pulse stretcher 870.

[0077] The first stage 864A may include, for example, an MO chamber module, in which an electrical discharge between electrodes (not shown) can cause a laser-emitting gas discharge in the laser-emitting gas to create population inversion of high-energy molecules such as argon, krypton, or xenon, thereby producing relatively broadband radiation. In a narrowbanding module ('LNM') within the first stage 864A, this radiation is narrowed to a relatively narrow bandwidth, and a center wavelength is selected. The first stage 864A may also include an MO output coupler (MOOC), which may include a mirror that, together with a reflective grating in the LNM, forms a partially reflective oscillator cavity in which the first stage 864A oscillates to form a first pulsed beam 865. The first stage 864A may also include other components such as a line center analysis module (LAM).

[0078] Optical element 866 may include an MO wavefront engineering box (WEB) that assists in redirecting the first pulse beam 865 to the second stage 864B. Optical element 866 may also include, for example, a beam-expanding optics having a prism beam expander (not shown) and, for example, a coherence-breaking optics in the form of an optical delay path (not shown).

[0079] The second stage 864B includes a PA chamber module, which is also an oscillator, formed, for example, by injecting a first pulsed beam 865 and an output coupling optics, and can be redirected through the gain medium in the PA chamber by a beam reverser. The output coupling optics may incorporate a partially reflective input / output coupler and a mirror with maximum reflection at the nominal operating wavelength (which can be around 193 nm for ArF systems), as well as one or more prisms. The second stage 864B optically amplifies the first pulsed beam 865 to form a second pulsed beam 867.

[0080] Each of the MO chamber module (first stage 864A) and the PA chamber module (second stage 864B) can be part of a gas discharge source such as an excimer light source. In such a source, the MO chamber module and the PA chamber module each include a gas mixture containing a combination of one or more inert gases (which may include argon, krypton, or xenon) and reactive gases (which may include fluorine or chlorine as a gain medium). Thus, for example, the gain medium in each module may include argon fluoride (ArF), krypton fluoride (KrF), or xenon chloride (XeCl). If the gain medium includes argon fluoride, the wavelength of the pulsed beam 861 is approximately 193 nm; if the gain medium includes krypton fluoride, the wavelength of the pulsed beam 861 is approximately 248 nm. The size of the microelectronic features patterned on the wafer (in the photolithography exposure apparatus 850) depends on the wavelength of the pulsed beam 861, with shorter wavelengths producing smaller minimum feature sizes.

[0081] The second pulse beam 861 is the input beam (similar to input beam 161) that is input to the optical pulse stretcher 870. At the optical pulse stretcher 870, a copy of the input beam 861 is delayed and recombined, thereby reducing speckle in the pulse output beam 863 that is guided to the photolithography exposure apparatus 850.

[0082] Examples of the dual-level light source 860 and the optical pulse stretcher 870 are described in WO 2021 / 076658, published by the applicant Cymer, LLC on 22 April 2021, the disclosure of which is incorporated herein by reference in its entirety.

[0083] In some embodiments, the optical pulse stretcher 870 includes a single pulse stretcher. In other embodiments, the optical pulse stretcher 870 includes multiple stages of pulse stretchers. For example, the pulse stretcher may include a plurality (at least two) of concave mirrors arranged relative to each other to form a confocal resonator. In some embodiments, as discussed in detail in WO 2021 / 076658, the optical pulse stretcher 870 includes a first optical pulse stretcher device 870-1 and a second optical pulse stretcher device 870-2 arranged as a series of stacked optical pulse stretcher devices. In these embodiments, the first optical pulse stretcher device 870-1 receives an input pulse beam 861 and delays and recombines a copy of the input pulse beam 861 to generate a first stretched pulse beam 818. The first broadened pulse beam 818 is then input to a second optical pulse broadener device 870-2, which delays and recombines a copy of the first broadened pulse beam 818 to generate a second broadened pulse beam 919. The second broadened pulse beam 919 is then input to a first optical pulse broadener device 870-1, where it is subsequently redirected as a pulse beam 863.

[0084] The optical pulse stretcher 870 includes a hermetically sealed housing 871, which includes a plurality of walls 806a, 806b, 806c, 806d, 806e, 806f, 806g, and 806h, which together define an internal cavity 873 housing the optical components or elements of devices 870-1 and 870-2. For simplicity, Figure 8 A two-dimensional illustration of a housing 871 with eight walls is shown, but the housing 871 is three-dimensional and may include walls extending in other directions or parallel to the page, or may have a different geometric configuration than shown.

[0085] The optical pulse stretcher 870 includes one or more through-wall modulators or actuators 825-j. Two actuators 825-1 and 825-2 are located in... Figure 8 The image is shown, in which the actuation device 825-1 and the optical elements within the first optical pulse stretcher device 870-1 are ( Figure 8 (not shown in the image) is associated with the actuation device 825-2 and the optical elements (not shown in the image) within the second optical pulse stretcher device 870-2. Figure 8 (Not shown in the image) associated with it. The optical pulse stretcher 870 may include fewer or more than two actuation devices 825-j, and each of the optical pulse stretcher devices 870-1, 870-2 may include one or more corresponding actuation devices 825-j.

[0086] Each optical pulse stretcher device 870-1, 870-2 may include one or more optical pulse stretchers, wherein each optical pulse stretcher includes one or more confocal resonators. The confocal resonators include reflective surfaces that are generally opposite each other and are arranged relative to each other such that a pulse beam (such as a second pulse beam 861 or a first stretched pulse beam 818) is reflected back and forth in the region between the reflective surfaces.

[0087] refer to Figure 9A ,based on Figure 1 Optical pulse stretcher 170 and Figure 8 The principle of the optical pulse stretcher 870 is illustrated by the implementation of the optical pulse stretcher 970. The optical pulse stretcher 970 includes a first optical pulse stretcher device 970-1 and a second optical pulse stretcher device 970-2 arranged as a series of stacked optical pulse stretcher devices. In these embodiments, the first optical pulse stretcher device 970-1 receives a second pulse beam 861 and delays and recombines a copy of the second pulse beam 961 to generate a first stretched pulse beam 918. This first stretched pulse beam 918 is then input to the second optical pulse stretcher device 970-2, which delays and recombines a copy of the first stretched pulse beam 918 to generate a second stretched pulse beam 919. The second broadened pulse beam 919 returns to the first optical pulse broadener device 970-1, and then in the first optical pulse broadener device 970-1, the second broadened pulse beam 919 is redirected as pulse beam 963.

[0088] The first optical pulse stretcher device 970-1 includes at least one optical pulse stretcher 903-1 within its cavity 973-1. The optical pulse stretcher 903-1 includes at least two opposing mirrors 902a and 902b that generate reflections between themselves and define a confocal resonator. For example, the optical pulse stretcher 903-1 may include a first single mirror 902a and a second single mirror 902b to generate two reflections of a delayed portion of the second pulse beam 961. As another example, the optical pulse stretcher 903-1 may include two first mirrors 902a and two second mirrors 902b to generate four reflections of a delayed portion of the second pulse beam 961. The mirrors 902a and 902b may be separated from each other by a sufficiently large physical distance to achieve the desired optical delay. In some implementations, the mirrors 902a and 902b are separated by a physical distance, for example, from about 1 meter (m) to about 3 m. This physical distance can provide an optical delay of approximately 30 nanoseconds (ns) to approximately 50 ns. Reflectors 902a and 902b can be circular and concave mirrors, respectively. Furthermore, the first optical pulse stretcher device 970-1 may include other optical elements. For example, a beam splitter 904 is positioned in the path of the second pulse beam 961 to split a portion of the second pulse beam 961 towards the optical pulse stretcher 903-1. A pair of beam splitters 904a and 904b can be positioned to split the first stretched pulse beam 918 to the second optical pulse stretcher device 970-2, and then recombin the second stretched pulse beam 919 from the second optical pulse stretcher device 970-2 to form the output beam 963.

[0089] The second optical pulse stretcher device 970-2 includes one or more confocal optical pulse stretchers within its cavity 973-2. In the example shown, there are three confocal optical pulse stretchers 903-2i, 903-2ii, and 903-2iii. Each optical pulse stretcher 903-2i, 903-2ii, and 903-2iii includes at least two corresponding opposing mirrors 970-ai, 970-bi; 970-aii, 970-bii; and 970-aiii, 970-biii. Although two opposing mirrors are shown in each pulse stretcher 903-2i, 903-2ii, and 903-2iii, each pulse stretcher 903-2i, 903-2ii, and 903-2iii may include more than two opposing mirrors.

[0090] The second optical pulse stretcher device 970-2 further includes an optical path arrangement 974 configured to receive a first stretched pulse beam 918, split the first stretched pulse beam 918 into portions, redirect the split portions to one or more pulse stretchers 903-2i, 903-2ii, and 903-2iii, and recombine the delayed split portions to form a second stretched pulse beam 919. Therefore, the optical path arrangement 974 includes one or more beam splitters and folding mirrors.

[0091] refer to Figure 9B An embodiment 974B of the optical path arrangement 974 is shown. The optical path arrangement 974B includes three beam splitters 975i, 975ii, and 975iii placed along the path of the first broadened pulse beam 918, wherein each beam splitter 975i, 975ii, and 975iii is configured to select a portion of the first broadened pulse beam 918 and guide that portion into a corresponding confocal optical pulse broadener 903-2i, 903-2ii, and 903-2iii. The optical path arrangement 974B also includes two folding mirrors 905c and 905d arranged to guide a second broadened pulse beam 919 (formed by transmitting portions of the first broadened pulse beam 918 through each of the confocal optical pulse broadeners 903-2i, 903-2ii, and 903-2iii) back to the first optical pulse broadener device 970-1.

[0092] Refer again Figure 9A The optical pulse stretcher 970 includes a hermetically sealed housing 971 containing multiple walls 906a, 906b, 906c, 906d, 906e, 906f, 906g, and 906h, which together define an internal cavity 973 housing the optical components or elements of devices 970-1 and 970-2. For simplicity, Figure 9A A two-dimensional illustration of a housing 971 with eight walls is shown, but the housing 971 is three-dimensional and may include walls extending in other directions or parallel to the page. The housing 971 may have different geometric configurations and may include different parts connected together.

[0093] The optical pulse stretcher 970 may include other elements not shown. For example, the optical pulse stretcher 970 may include optical elements for aligning other optical elements within the optical pulse stretcher. Such alignment means may be configured to selectively interact with the first stretched pulse beam 918 and / or the second stretched pulse beam 919. Additional alignment means may be used at other locations along the path of the beam passing through the optical pulse stretcher 970. For example, alignment means may be used to visualize the first stretched pulse beam 918, and alignment means may be used to visualize the second stretched pulse beam 919.

[0094] The device 970 includes one or more through-wall adjusters or actuating devices 925-j. Actuating devices 925-1, 925-2, 925-3, 925-4, 925-5, and 925-6 are respectively associated with mirrors 970-biii, 970-bii, 970-bi, 970-ai, 970-aii, and 970-aiii of optical pulse stretchers 903-2i, 903-2ii, and 903-2iii. Actuating devices 925-7 and 925-8 are respectively associated with mirrors 902a and 902b of optical pulse stretcher 903-1. Finally, at least one actuating device 925-9 is associated with optical elements within the optical path arrangement 974. Actuating devices 925-1, 925-2, and 925-3 are installed in wall 906a as through-wall adjusters; actuating device 925-7 is installed in wall 906d as a through-wall adjuster; actuating device 925-8 is installed in wall 906e as a through-wall adjuster; actuating devices 925-6, 925-7, and 925-8 are installed in wall 906g as through-wall adjusters; and actuating device 925-9 is installed in wall 906h as a through-wall adjuster. The optical pulse stretcher device 970 may include fewer or more than nine actuating devices 925-j, and each of the optical pulse stretcher devices 970-1 and 970-2 may include one or more corresponding actuating devices 925-j.

[0095] refer to Figure 9B More than one actuating device 925-9 may be installed in the wall as a through-wall adjuster to access one or more optical components within the optical path arrangement 974B. In this embodiment, two actuating devices 925-9 and 925-10 may be installed at the wall 906h respectively for controlling and adjusting the corresponding reflectors 905c and 905d.

[0096] Each mirror 905c, 905d can constitute an optical element such as an optical element 105 that needs to be adjusted. Each mirror 905c, 905d within the optical pulse stretcher device 970-1 or 970-2 needs to be adjusted (e.g., aligned or changed in position or angle). For example, to ensure that the beam 918 is properly aligned with and passes through the mirror 905d optically downstream of mirror 905c, mirror 905c may need to be translated along or rotated about one or more local axes. Furthermore, such adjustments to one or more mirrors of mirrors 905c, 905d can occur when the beam 918 or 919 interacts with mirrors 905c, 905d. For this purpose, mirror 905c is positioned (e.g., fixed or constrained) at and controlled by adjustable mounting device 910c, and mirror 905d is positioned (e.g., fixed or constrained) at and controlled by adjustable mounting device 910d. Adjustable mounting device 910c aligns beam 918 with an optical element downstream of mirror 905c, and adjustable mounting device 910d aligns beam 919 with an optical element downstream of mirror 905d. Each adjustable mounting device 910c, 910d is designed according to the principle of adjustable mounting device 110, and therefore includes a corresponding passive alignment mount 120 and a corresponding drive mechanism 130 mechanically coupled to the corresponding passive alignment mount 120. In some embodiments, the adjustable mounting device 910c may be designed similarly to the adjustable mounting device 210 or 310, and the adjustable mounting device 910d may be designed similarly to the adjustable mounting device 210 or 310. In these embodiments, the actuating devices 925-9 may include a pair of actuating devices, each coupled to a corresponding drive system 330A or 330C within the drive mechanism 330, and the actuating devices 925-10 may include a pair of actuating devices, each coupled to a corresponding drive system 330A or 330C within the drive mechanism 330. Furthermore, each reflector 905c, 905d is stabilized within a corresponding reflector unit 921c, 921d, wherein each reflector unit 921c, 921d is mounted to a structure (such as structure 331) of the drive mechanism 330.

[0097] The operation of adjustable mounting devices 910c and 910d is similar to that of the adjustable mounting device 310 described above.

[0098] Other optical elements within the optical pulse stretcher 870 can be positioned (e.g., fixed or constrained) in their respective adjustable mounts, which are designed to resemble the adjustable mounts 110, 210, 310, and controlled by their respective adjustable mounts.

[0099] In other embodiments, and again refer to Figure 3A and 3B The passive alignment mount 320 may be part of a kinematic mount or a pseudo-kinematic mount, which includes three contact elements 320A', 320B', 320C' that are of different designs from contact elements 320A, 320B, 320C. For example, in other embodiments, each of contact elements 320A', 320B', 320C' is a groove or linear indentation defined in a contact body (similar to contact element 320C).

[0100] In other embodiments, and again refer to Figures 6A-6D The pin 640 may have a shape other than that of a cylinder (where its cross-sectional shape is circular). For example, the pin 640 may have an elliptical or polygonal cross-sectional shape. In other embodiments, and again refer to Figure 7A and 7B The rod 742 may have a shape other than that of a cylinder (where its cross-sectional shape is circular). For example, the rod 742 may have an elliptical or polygonal cross-sectional shape.

[0101] See Figure 10 An embodiment 1010 of the adjustable mounting device 310 is shown. The adjustable mounting device 1010 includes a passive alignment mount 1020 positioned and aligned with the optical element unit 1021, at which the optical element ( Figure 10 Not shown, but could be any optical element 105, is housed in opening 1022. Adjustable mounting device 1010 includes a drive mechanism 1030 (partially shown) mechanically coupled to passive alignment mount 1020, the drive mechanism 1030 being carried by a solid structure or body such as... Figure 3A The passive alignment mount 1020 and the optical element are constrained by the body 331. The drive mechanism 1030 transmits mechanical constraints and / or motion to the passive alignment mount 1020 and the optical element. In this way, the passive alignment mount 1020 and the drive mechanism 1030 combine to provide the ability to tilt and / or yaw (relative to X) the optical element. 105 axis or Y 105 The tilting / tilting mechanism of the shaft (without disturbing the cavity 173 equipped with the optical system 300) is used without disrupting the cavity 173 (with the shaft) Figure 1 A controlled environment within.

[0102] The passive alignment mount 1020 includes three contact elements 1020A, 1020B, and 1020C, and the drive mechanism 1030 includes three drive systems 1030A, 1030B, and 1030C (in... Figure 10(shown in the middle section), wherein each drive system 1030A, 1030B, 1030C is associated with a corresponding and specific contact element 1020A, 1020B, 1020C.

[0103] The passive alignment mount 1020 is part of a kinematic mount or pseudo-kinematic mount. That is, the kinematic mount (or pseudo-kinematic mount) is formed between the passive alignment mount 1020 and the drive mechanism 1030, thereby creating stiffness in six independent degrees of freedom (DOF) or directions between the two bodies (optical element 105 and drive mechanism 1030).

[0104] In this embodiment, the kinematic mount includes three contact elements 1020A, 1020B, and 1020C. Contact element 1020A is a first groove defined in a first contact body along a first axial direction 1023A. Contact element 1020B is a second groove defined in a second contact body along a second axial direction 1023B. Contact element 1020C is a third groove defined in a third contact body along a third axial direction 1023C. Each axial direction (such as 1023A) is different from the other two axial directions (e.g., 1023B, 1023C), and each axial direction is located at X... 1005 Y 1005 Inside the face.

[0105] Each drive system 1030A, 1030B, 1030C includes a corresponding wedge 1035A, 1035B, 1035C, and each wedge is correspondingly subject to rotational constraints 1036A, 1036B, and 1036C, as discussed in detail above.

[0106] The implementation method may be further described using the following terms: 1. An optical system in a pulse stretcher for a deep ultraviolet light source, the optical system comprising: An optical element, which is configured during operation along the path of a beam of light generated by a deep ultraviolet light source; and An adjustable mounting device is provided, to which the optical element is positioned. The adjustable mounting device includes: Passive alignment mount, and A drive mechanism coupled to a passive alignment mount, the drive mechanism including a rotationally constrained wedge. 2. The optical system according to Clause 1, wherein the optical element is a reflective optical element, a partially reflective beam splitter, a diffractive optical element, or a refractive optical element. 3. The optical system according to Clause 2, wherein the passive alignment mount includes a kinematic mount or a pseudo-kinematic mount. 4. The optical system according to Clause 1, wherein the passive alignment mount includes a kinematic mount. 5. The optical system according to Clause 4, wherein the kinematic mount comprises: flat surface Groove, and Chengwo. 6. The optical system according to Clause 5, wherein the drive mechanism includes a first round tip abutting a flat surface, a second round tip abutting a groove, and a third round tip abutting a socket. 7. The optical system according to Clause 5, wherein the first round tip abutting the flat surface provides five degrees of freedom, the second round tip abutting the groove provides four degrees of freedom, and the third round tip abutting the recess provides three degrees of freedom. 8. The optical system according to Clause 4, wherein the kinematic mount includes a first groove defined along a first axial direction, a second groove defined along a second axial direction, and a third groove defined along a third axial direction, each axial direction being different from the other two axial directions. 9. The optical system according to Clause 1, wherein a passive alignment mount is positioned and aligned to an optical element unit housing optical elements. 10. The optical system according to Clause 1, wherein the drive mechanism comprises a plurality of drive systems, each drive system being associated with a contact element of a passive alignment mount, wherein at least one drive system comprises: A pin, comprising a rounded tip at a first end and a wedge at a second end, the rounded tip abutting against one of the contact elements of a passive alignment mount; and The rod includes a spherical tip constrained by a pin's wedge. 11. The optical system according to Clause 10 further includes a structure defining a plurality of cylindrical openings, each cylindrical opening receiving a pin or rod, wherein the structure constrains and guides each pin and each rod received within its respective cylindrical opening. 12. The optical system according to Clause 10, wherein translation of the rod in a first direction causes the spherical tip of the rod to translate in the first direction, the spherical tip engaging with the wedge and causing the pin to translate in a second direction different from the first direction. 13. The optical system according to Clause 12, wherein the second direction is perpendicular to the first direction. 14. The optical system according to Clause 10, wherein the passive alignment mount includes a kinematic mount, and the contact element of the kinematic mount is one of the following elements: a flat surface, a recess, or a groove. 15. The optical system according to Clause 10, wherein the rod of each drive system is adjustable from the outside of the housing containing the optical elements. 16. The optical system according to Clause 1, wherein the drive mechanism comprises three drive systems, each drive system being associated with a contact element of a passive alignment mount, wherein one drive system provides a linearly constrained fixed point at the corresponding contact element, and the other two drive systems are configured to move the corresponding contact element. 17. The optical system according to Clause 1, wherein the passive alignment mount includes a plurality of contact elements, each contact element comprising hardened stainless steel. 18. The optical system according to Clause 17, wherein the drive mechanism comprises a plurality of drive systems, each drive system being associated with a contact element of a passive alignment mount, at least two of the drive systems comprising a wedge and a round tip, both of which are made of a hardened material with a hardness greater than or equal to 1400 N / mm². 19. The optical system according to Clause 17, wherein the drive mechanism comprises a plurality of drive systems, each drive system being associated with a contact element of a passive alignment mount, at least two of the drive systems comprising a wedge and a round tip, both of which are made of a hardened material with a hardness greater than or equal to 2075 N / mm². 20. The optical system according to Clause 19, wherein the wedge and the rounded tip are made of hardened stainless steel. 21. The optical system according to Clause 19, wherein each wedge and each round tip includes a polished surface treatment with a roughness of Ra 0.8 micrometers (Ra 32 microinches, 35 RMS) or less. 22. The optical system according to Clause 19, wherein each wedge and each round tip includes a polished surface treatment with a roughness of Ra 0.4 micrometers (Ra 16 microinches, 17.6 RMS) or better. 23. The optical system according to Clause 1, wherein the adjustable mounting device is free of lubricant. 24. The optical system according to Clause 1, wherein the optical element is a first optical element, and the adjustable mounting device is a first adjustable mounting device, the first optical element being positioned to the first adjustable mounting device, the first adjustable mounting device including a first kinematic mount and a first wedge adjustment mechanism coupled to the first kinematic mount, and The optical system further includes a second optical element disposed relative to the first optical element, and a second adjustable mounting device to which the second optical element is positioned, the second adjustable mounting device comprising: Second kinematic mounting component, and A second wedge adjustment mechanism is coupled to a second kinematic mount. 25. The optical system according to Clause 1, wherein the wedge includes a flat surface at the end of the pin, the pin extends in the axial pin direction, and the normal of the flat surface extends between 20° and 40° relative to the axial pin direction. 26. The optical system according to Clause 25, wherein the drive mechanism includes a wing extending from the pin and adjacent to an end of a flat surface of the wedge, the wing providing rotational constraint on the wedge. 27. The optical system according to Clause 1, wherein the adjustable mounting means is configured to achieve tilt adjustment of the optical elements in pitch and roll. 28. An optical system within a pulse stretcher of a deep ultraviolet light source, the optical system comprising: A pair of folding mirrors, which are configured in operation along the path of a beam generated by a deep ultraviolet light source, are used to guide the beam from a first part of the pulse stretcher to a second part of the pulse stretcher. A pair of mirror units are mounted to the structure, each folded mirror remaining stable within its respective mirror unit; and A pair of adjustable mounting devices, wherein each mirror unit is positioned at a corresponding adjustable mounting device, each adjustable mounting device including a passive alignment mount associated with each mirror unit and a drive mechanism associated with each passive alignment mount, the drive mechanism including a rotationally constrained wedge. 29. The optical system according to Clause 28, wherein the adjustable mounting device is configured to achieve tilt adjustment in pitch and roll of a folding mirror that remains stable in a mirror unit positioned at the adjustable mounting device. 30. An adjustable mounting device, wherein the optical elements of a pulse stretcher are positioned within the adjustable mounting device, the adjustable mounting device being disposed within a controlled environment of the pulse stretcher housing, the adjustable mounting device comprising: The unit, to which the optical elements are positioned; A passive alignment mount, which is associated with the cell, and A drive mechanism coupled to a passive alignment mount, at least a portion of which is controllable from outside the pulse stretcher housing, the drive mechanism including a rotationally constrained wedge.

[0107] Other embodiments are within the scope of the following claims.

Claims

1. An optical system in a pulse stretcher of a deep ultraviolet light source, said optical system comprising: Optical elements are configured during operation along the path of the light beam generated by the deep ultraviolet light source; as well as An adjustable mounting device is provided, wherein the optical element is positioned within the adjustable mounting device, the adjustable mounting device comprising: Passive alignment mount, and A drive mechanism coupled to the passive alignment mount, the drive mechanism including a wedge that is rotationally constrained.

2. The optical system according to claim 1, wherein the optical element is a reflective optical element, a partially reflective beam splitter, a diffractive optical element, or a refractive optical element.

3. The optical system of claim 2, wherein the passive alignment mount comprises a kinematic mount or a pseudo-kinematic mount.

4. The optical system of claim 1, wherein the passive alignment mount comprises a kinematic mount.

5. The optical system of claim 4, wherein the kinematic mount comprises: flat surface Groove, and Chengwo.

6. The optical system of claim 5, wherein the driving mechanism includes a first round tip, a second round tip, and a third round tip, the first round tip abutting the flat surface, the second round tip abutting the groove, and the third round tip abutting the socket.

7. The optical system of claim 5, wherein the first rounded tip abutting the flat surface provides five degrees of freedom, the second rounded tip abutting the groove provides four degrees of freedom, and the third rounded tip abutting the recess provides three degrees of freedom.

8. The optical system of claim 4, wherein the kinematic mount includes a first groove, a second groove, and a third groove, the first groove being defined along a first axial direction, the second groove being defined along a second axial direction, and the third groove being defined along a third axial direction, each axial direction being different from the other two axial directions.

9. The optical system of claim 1, wherein the passive alignment mount is positioned and aligned to the optical element unit, the optical element unit accommodating the optical element.

10. The optical system of claim 1, wherein the driving mechanism comprises a plurality of driving systems, each driving system being associated with a contact element of the passive alignment mount, wherein at least one of the driving systems comprises: The pin includes a rounded tip at a first end and a wedge at a second end, the rounded tip abutting against one of the contact elements of the passive alignment mount; as well as The rod includes a spherical tip, which is constrained by the wedge of the pin.

11. The optical system of claim 10, further comprising a structure defining a plurality of cylindrical openings, each cylindrical opening receiving a pin or rod, wherein the structure constrains and guides each pin and each rod received within the respective cylindrical opening of the structure.

12. The optical system of claim 10, wherein translation of the rod along a first direction causes the spherical tip of the rod to translate along the first direction, the spherical tip engaging with the wedge, and causes the pin to translate along a second direction, the second direction being different from the first direction.

13. The optical system of claim 12, wherein the second direction is perpendicular to the first direction.

14. The optical system of claim 10, wherein the passive alignment mount comprises a kinematic mount, and the contact element of the kinematic mount is one of: a flat surface, a recess, or a groove.

15. The optical system of claim 10, wherein the rod of each drive system is adjustable from outside the housing, and the optical element is housed within the housing.

16. The optical system of claim 1, wherein the drive mechanism comprises three drive systems, each drive system being associated with a contact element of the passive alignment mount, wherein one drive system provides a linearly constrained fixed point at the corresponding contact element, and the other two drive systems are configured to move the corresponding contact element.

17. The optical system of claim 1, wherein the passive alignment mount comprises a plurality of contact elements, each contact element comprising hardened stainless steel.

18. The optical system of claim 17, wherein the drive mechanism comprises a plurality of drive systems, each drive system being associated with a contact element of the passive alignment mount, at least two of the drive systems comprising the wedge and the rounded tip, both the wedge and the rounded tip having a hardness greater than or equal to 1400 N / mm². 2 It is made of hardened material.

19. The optical system of claim 17, wherein the drive mechanism comprises a plurality of drive systems, each drive system being associated with a contact element of the passive alignment mount, at least two of the drive systems comprising the wedge and the rounded tip, both the wedge and the rounded tip having a hardness greater than or equal to 2075 N / mm². 2 It is made of hardened material.

20. The optical system of claim 19, wherein the wedge and the rounded tip are made of hardened stainless steel.

21. The optical system of claim 19, wherein each wedge and each round tip comprises a polished surface treatment having a roughness of Ra 0.8 micrometers (Ra 32 microinches, 35 RMS) or less.

22. The optical system of claim 19, wherein each wedge and each round tip comprises a polished surface treatment having a roughness of Ra 0.4 micrometers (Ra 16 microinches, 17.6 RMS) or better.

23. The optical system of claim 1, wherein the adjustable mounting device is free of lubricant.

24. The optical system of claim 1, wherein the optical element is a first optical element, and the adjustable mounting device is a first adjustable mounting device, the first optical element being positioned to the first adjustable mounting device, the first adjustable mounting device comprising a first kinematic mount and a first wedge adjustment mechanism, the first wedge adjustment mechanism being coupled to the first kinematic mount, and The optical system further includes a second optical element and a second adjustable mounting device, the second optical element being arranged relative to the first optical element and positioned to the second adjustable mounting device, the second adjustable mounting device comprising: Second kinematic mounting component, and The second wedge adjustment mechanism is coupled to the second kinematic mounting component.

25. The optical system of claim 1, wherein the wedge includes a flat surface at the end of the pin, the pin extending along the axial pin direction, and the normal of the flat surface extending between 20° and 40° relative to the axial pin direction.

26. The optical system of claim 25, wherein the drive mechanism includes a wing extending from the pin and adjacent to an end of the flat surface of the wedge, the wing providing rotational constraint on the wedge.

27. The optical system of claim 1, wherein the adjustable mounting device is configured to achieve tilt adjustment of the optical element in pitch and roll.

28. An optical system, located within a pulse stretcher of a deep ultraviolet light source, the optical system comprising: A pair of folding mirrors, which are configured in operation along the path of a beam generated by the deep ultraviolet light source to guide the beam from a first portion of the pulse stretcher to a second portion of the pulse stretcher; A pair of mirror units are mounted to the structure, and each folded mirror remains stable in its respective mirror unit; as well as A pair of adjustable mounting devices, wherein each mirror unit is positioned at a corresponding adjustable mounting device, each adjustable mounting device including a passive alignment mount associated with each mirror unit and a drive mechanism associated with each passive alignment mount, the drive mechanism including a wedge that is rotationally constrained.

29. The optical system of claim 28, wherein the adjustable mounting device is configured to achieve tilt adjustment of the folding mirror in pitch and roll, the folding mirror remaining stable in the mirror unit positioned at the adjustable mounting device.

30. An adjustable mounting device for positioning optical elements of a pulse stretcher within the adjustable mounting device, the adjustable mounting device being disposed within a controlled environment of a pulse stretcher housing, the adjustable mounting device comprising: The unit, wherein the optical element is positioned; A passive alignment mount, associated with the unit, and A drive mechanism coupled to the passive alignment mount, at least a portion of which is controllable from outside the pulse stretcher housing, the drive mechanism including a wedge that is rotationally constrained.

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