KR102548949B1 - Z/Tilt stage and control system thereof for aligning mask - Google Patents

Abstract

The technology disclosed herein is a Z/Tilt stage for mask alignment, comprising: one or more Z-axis linear stages for moving and tilting a platform; and one or more Z/Tilt flexures configured to guide movement and tilting of the platform, wherein the Z-axis linear stage comprises: a body; a Z-axis guide flexure for limiting movement of the Z-axis linear stage out of the Z-axis direction; and a driving unit for applying a driving force to the Z-axis linear stage.

Description

Z/Tilt stage and control system for mask alignment

The technology disclosed herein relates to a Z/Tilt stage and a control system for mask alignment, and more specifically, a flexure and a It relates to a Z/Tilt stage implemented using a coupling member and a control system thereof.

In order to effectively inspect masks used in semiconductor processes such as EUVL (Extreme Ultra-Violet Lithography), precision of a transfer device for mask alignment is very important. Therefore, there is a demand for development of devices and systems for reducing tolerances generated during the movement of these stages and for precisely controlling them.

In the conventional conveying device, when a driving force is applied, there is a possibility that a load may be generated on a structure such as a motor due to a force other than the intended direction generated due to the above-mentioned tolerance, and also, when transmitting a driving force to a platform, it is possible to easily Since it cannot be transmitted directly through the structure and an additional configuration must be used, the complexity of the system increases.

Therefore, in order to solve the problems of these existing transfer devices, there is a growing need to develop a Z/Tilt stage that can transmit driving force directly to the platform with a simple structure and can reduce the load on the device due to tolerances and enable more precise control. It is increasing.

The present invention aims to solve the above problems and other problems related thereto.

An exemplary object of the present specification is to transfer the Z/Tilt stage in the Z-axis direction, and to perform a tilting operation of the stage by using a flexure and a coupling member to provide a more precise Z/Tilt than conventional transfer devices. It is to provide a tilt stage and its control system.

The technical task to be achieved by the Z/Tilt stage and control system according to the technical idea of the technology disclosed in this specification is not limited to the task for solving the above-mentioned problems, and other tasks not mentioned are common from the following description. will be clearly understandable to the technicians of

A Z/Tilt stage for mask alignment according to an embodiment of the technology disclosed herein includes one or more Z-axis linear stages for moving and tilting a platform; and one or more Z/Tilt flexures configured to guide movement and tilting of the platform, wherein the Z-axis linear stage comprises: a body; a Z-axis guide flexure for limiting movement of the Z-axis linear stage out of the Z-axis direction; and a driving unit for applying a driving force to the Z-axis linear stage.

In the Z / Tilt stage, the pair of Z-axis guide flexures are arranged in pairs above and below the main body, and each Z-axis guide flexure shares the same Z-axis to constrain tilt freedom to each other can be configured to

The Z / Tilt stage further includes force coupling flexures, the driving force coupling flexures are disposed between the Z-axis linear stage and the platform, and the driving force coupling flexures Only the driving force in the Z-axis direction of the Z-axis linear stage may be transmitted to the platform through its deformation.

In the Z/Tilt stage, the Z/Tilt flexure may be configured to restrict a degree of freedom of the platform in an X-Y plane direction and allow only Z-axis movement and θx- and θy-direction tilting.

In the Z/Tilt stage, the Z-axis linear stage may further include a local sensor for measuring a position and displacement of the Z-axis linear stage.

The Z/Tilt stage may further include a global sensor for measuring the position and displacement of the platform.

A Z/Tilt stage control system for mask alignment according to another embodiment of the technology disclosed herein includes a controller; one or more Z-axis linear stages for moving and tilting the platform; and one or more Z/Tilt flexures configured to guide movement and tilting of the platform, wherein the Z-axis linear stage includes: a body, and restricts movement of the Z-axis linear stage outside the Z-axis direction. A Z-axis guide flexure and a driving unit, wherein the driving unit applies a driving force to the Z-axis linear stage, and the pair of Z-axis guide flexures guide the Z-axis linear stage to be transported only in the Z-axis direction. can do.

In the control system, the Z-axis guide flexures are disposed in pairs above and below the main body, and when a driving force is applied, they share the same Z-axis and are deformed by themselves to guide the Z-axis linear stage.

The control system further includes a driving force coupling flexure, wherein the driving force coupling flexure controls the driving force of the Z-axis linear stage in the Z-axis direction through deformation of the driving force coupling flexure itself. may be transferred to the platform, and the one or more Z/Tilt flexures may constrain the degree of freedom of the platform in the X-Y plane direction and allow only Z-axis transfer and θx and θy-direction tilting operations.

In the control system, the Z-axis linear stage further includes a local sensor, the local sensor measures the position and displacement of the Z-axis linear stage and provides the measured position and displacement to the controller, and the controller measures the local sensor. The Z-axis linear stage may be controlled by calculating a position of the platform using a position and displacement of the Z-axis linear stage provided from a sensor.

The control system further comprises a global sensor, wherein the global sensor measures the position and displacement of the platform and provides the measured position and displacement of the platform to the controller, and the controller measures the position and displacement of the platform provided by the global sensor. It is possible to directly control the position of the platform by using.

The Z/Tilt stage and its system according to an embodiment of the technology disclosed herein have the following effects.

According to the present invention, a driving force can be directly transmitted to a platform with a simple structure without an additional configuration using a flexure that is deformed by itself.

In addition, it is possible to provide a Z/Tilt stage and its system capable of more precise control by reducing the load of the device caused by the tolerance.

However, effects according to one embodiment of the technology disclosed in this specification are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

In order to more fully understand the drawings cited herein, a brief description of each drawing is provided.
1A shows each configuration of a Z/Tilt stage according to an embodiment of the technology disclosed herein.
1B shows the platform of the Z/Tilt stage disclosed herein.
2 shows a detailed structure of a Z-axis linear stage disclosed in this specification.
3 illustrates the structure and operation of a driving force coupling flexure disclosed in this specification.
4 shows a detailed configuration of the Z/Tilt stage disclosed in this specification.

Since the technology disclosed in this specification can have various changes and various embodiments, specific embodiments are illustrated in the drawings and will be described in detail through detailed description. However, this is not intended to limit the technology disclosed in this specification to specific embodiments, and it is understood that the technology disclosed in this specification includes all modifications, equivalents, and substitutes included in the spirit and technical scope of the technology disclosed in this specification. It should be.

In describing the technology disclosed in this specification, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the technology disclosed in this specification, the detailed description thereof will be omitted. In addition, numbers (eg, 1st, 2nd, etc.) used in the description process of this specification are only identifiers for distinguishing one component from another component.

In addition, in this specification, when one component is referred to as “connected” or “coupled” with another component, the one component may be directly connected or coupled to the other component, but in particular the opposite As long as no description exists, it will be understood that they may be connected or coupled via another component in the middle.

In addition, in the present specification, components expressed as '~ part' may be two or more components combined into one component, or one component may be differentiated into two or more for each more subdivided function. In addition, each of the components to be described below may additionally perform some or all of the functions of other components in addition to its own main function, and some of the main functions of each component may be different from other components. Of course, it may be performed exclusively by a component.

Expressions such as "first", "second", "first", or "second" used in various embodiments may modify various elements regardless of order and/or importance, and the elements Not limited. For example, a first element may be termed a second element, and similarly, a second element may also be termed a first element without departing from the scope of the technology disclosed herein.

Hereinafter, the Z/Tilt stage and its system according to a preferred embodiment will be described in detail.

Figures 1a and 1b show the main configuration of the Z / Tilt stage disclosed in this specification.

In FIG. 1A, the Z-axis linear stage 101 shows that one or more of the Z-axis linear stages 101 can be configured to enable Z-axis-direction feed or θx- and θy-direction tilting operations. When one or more Z-axis linear stages 101 all move in the Z-axis direction, the platform 104 shown in FIG. 1B can be transferred in the Z-axis direction without tilting. In addition, when some of the one or more Z-axis linear stages 101 move in the Z-axis direction, the platform 104 shown in FIG. 1B may be tilted in θx and θy directions.

Also in FIG. 1A , the Z/Tilt stage includes one or more Z/Tilt flexures 102, the Z/Tilt flexures 102 having the platform 104 rotate in the Z axis, θx and θy directions. It serves to guide the platform 104 so that it can have only degrees of freedom. Therefore, when the Z/Tilt stage is driven by the driver 203, the platform 104 hardly moves in the X-axis, Y-axis, and θz directions.

The guide operation of the Z/Tilt flexure 102 is weak in the direction in which the Z/Tilt flexure 102 guides the platform 104 and has strong rigidity in other directions, so that the Z/Tilt flexure 102 has Z/Tilt flexure 102. It is performed through the deformation of the tilt flexure 102 itself. Accordingly, when the Z/Tilt stage is driven by the driver 203, the Z/Tilt flexure 102 may bend or deform itself to minimize movement outside of the intended direction.

2 shows a detailed structure of the Z-axis linear stage 101 disclosed in this specification.

The Z-axis linear stage 101 may include a body 201, one or more Z-axis guide flexures 202, a driving unit 203, and a local sensor 204. The Z-axis linear stage 101 can move in the Z-axis direction with a driving force applied from the driving unit 203, and the Z-axis linear stage 101 of the present invention minimizes movement in directions other than the Z-axis direction. To do so, a Z-axis guide flexure 202 may be further included. The one or more Z-axis guide flexures 202 are arranged in pairs above and below the Z-axis linear stage 101, and the pair of Z-axis guide flexures 202 share the same Z-axis, thereby increasing the tilt direction. The degrees of freedom of are constrained to each other, and finally, only the Z-axis degree of freedom remains. Therefore, when the Z-axis linear stage 101 is operated by the drive unit 203, the pair of Z-axis guide flexures 202 are deformed by themselves so that driving force is transmitted only in the Z-axis direction, and in other directions It barely works.

The driver 203 may be various types of actuators capable of transmitting driving force to the Z-axis linear stage 101, for example, a piezomotor, a VCM, a linear motor, etc. It is not limited.

In addition, the Z-axis guide flexure 202 may be made of a deformable material capable of adjusting the degree of freedom in a desired direction, and is not limited to a specific material. In addition, since the Z-axis guide flexures 202 are arranged in pairs above and below the main body 201, the Z-axis direction transfer operation can be performed simply and efficiently without an additional configuration that implements the Z-axis direction transfer in the existing prior art. can be done

The Z-axis linear stage 101 may further include a local sensor 204 , and the local sensor 204 may be a sensor that measures the position and displacement of the Z-axis linear stage 101 . The local sensor 204 may transmit the measured data to a controller, and the controller calculates the current position of the platform 104 based on the data to move the Z-axis linear stage 101 more precisely. You can control it.

3 illustrates the structure and operation of the driving force coupling flexure 103 disclosed herein.

The driving force coupling flexure 103 may be disposed above the main body 201 of FIG. 2 and may be disposed below the platform 104 . The driving force coupling flexure 103 may be configured to have high rigidity only in the Z-axis direction and low rigidity in other directions by using its own elastic deformation, and is not limited to a specific shape. Therefore, it can be composed of any material and shape that satisfies the above conditions.

As shown in (a) to (c) of FIG. 3, the driving force coupling flexure 103 may be configured in various forms capable of forming a low stiffness other than the Z-axis direction, and (a) to (c) are An example of one of the shapes is shown from various angles. In the case of (d) and (e) of FIG. 3 , the driving force coupling flexure 103 is deformed such that it is bent to a lower rigidity side, thereby showing an operation of transmitting the driving force in the Z-axis direction.

As described above, the Z-axis linear stage 101 can only move in the Z-axis direction, and therefore, during a tilting operation of the platform 104, only the tilted platform 104 and the Z-axis direction A coupling member capable of absorbing the angular difference between the moved Z-axis linear stages 101 is required. Therefore, the driving force coupling flexure 103 is designed as a structure having low rigidity in an inclined direction in order to absorb such a tilt difference. Therefore, there is an effect of preventing abnormal operation of the stage device through the driving force coupling flexure 103 as described above, and implementing a more precisely controlled device.

Also, referring to FIG. 1 , the platform 104 is guided so that only movement in the Z-axis direction and tilting operations in the θx and θy directions are possible due to the Z/Tilt flexure 102 . In other words, since it does not have degrees of freedom in the X-axis, Y-axis, and θz directions, it hardly moves in the corresponding directions even when a driving force is applied. However, when the Z-axis linear stages 101 apply a driving force to the platform 104 in a direction other than the Z-axis direction due to an assembly tolerance during actual driving, the load on the driving unit 203 increases. Therefore, it may cause abnormal operation of the stage and the entire system. Therefore, in order to prevent such an abnormal operation in the actual process, the driving force coupling flexure 103 having low stiffness in the direction other than the Z-axis absorbs the deformation according to the tolerance generated by the driving force applied in the direction other than the Z-axis direction, The load of (203) can be minimized.

4 shows a detailed configuration of the Z/Tilt stage disclosed in this specification.

In FIG. 4 , it is shown that the Z/Tilt stage may further include the above-described local sensor 204 and/or global sensor 105 . Accordingly, the Z/Tilt stage may include only the local sensor 204 and the global sensor 105, or may be configured to include both the local sensor 204 and the global sensor 105 at the same time.

The global sensor 105 is used to directly observe and control the position and displacement of the platform 104 . In an ideal case without machining/assembly tolerance, the Z/Tilt stage can be controlled by calculating and predicting the position of the platform 104 only with the local sensor 204 from the viewpoint of static displacement control. It may be difficult to precisely control the position and displacement of the platform 104 using only the sensor 204 . Accordingly, the Z/Tilt stage may further include a global sensor 105 that directly measures the position and displacement of the platform 104, thereby having an effect of directly controlling the position of the platform 104 more precisely.

The method described above and control thereof may be implemented as a hardware component, a software component, and/or a combination of hardware components and software components. For example, the methods and components described in the embodiments include a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), and a programmable PLU (programmable logic unit). logic unit), microprocessor, or any other device capable of executing and responding to instructions. The processing device may run an operating system (OS) and one or more software applications running on the operating system. A processing device may also access, store, manipulate, process, and generate data in response to execution of software. For convenience of understanding, there are cases in which one processing device is used, but a person skilled in the art will understand that the processing device may include a plurality of processing elements and/or a plurality of types of processing elements. it can be seen that there is For example, a processing device may include a plurality of processors or a processor and a controller. Other processing configurations are also possible, such as parallel processors.

Software may include a computer program, code, instructions, or a combination of one or more of the foregoing, which configures a processing device to operate as desired or, independently or in combination, instructs the processing device. can do. Software and/or data may be permanently or temporarily stored in any tangible machine, component, physical device, virtual device, computer storage medium or device for interpretation by a processing device or to provide instructions or data to a processing device. can materialize. The software may be distributed on networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer readable media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. Program commands recorded on the medium may be specially designed and configured for the embodiment or may be known and usable to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. - includes hardware devices specially configured to store and execute program instructions, such as magneto-optical media, and ROM, RAM, flash memory, and the like. Examples of program instructions include high-level language codes that can be executed by a computer using an interpreter, as well as machine language codes such as those produced by a compiler. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

As described above, although the embodiments have been described with limited examples and drawings, those skilled in the art can make various modifications and variations from the above description. For example, the described techniques may be performed in an order different from the method described, and/or components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved.

Therefore, other implementations, other embodiments, and equivalents of the claims are within the scope of the following claims.

101: Z-axis linear stage
102: Z/Tilt flexure
103: driving force coupling flexure
104: platform
105: global sensor
201: body
202: Z-axis guide flexure
203: driving unit
204: local sensor

Claims (11)

As a Z/Tilt stage for mask alignment,
one or more Z-axis linear stages for moving and tilting the platform; and
Z/Tilt flexures configured to be one or more elastic deformations configured to guide movement and tilting of the platform;
The Z-axis linear stage:
body;
a Z-axis guide flexure configured to be elastically deformed to limit movement of the Z-axis linear stage out of the Z-axis direction; and
Including a driving unit for applying a driving force to the Z-axis linear stage,
Z/Tilt stage for mask alignment. According to claim 1,
The Z-axis guide flexure,
Disposed in pairs above and below the main body, each Z-axis guide flexure shares the same Z-axis and is configured to constrain tilt freedom to each other,
Z/Tilt stage for mask alignment. According to claim 1,
Further comprising force coupling flexures,
The driving force coupling flexure,
It is disposed between the Z-axis linear stage and the platform, and transfers only the Z-axis direction driving force of the Z-axis linear stage to the platform through deformation of the driving force coupling flexure itself.
Z/Tilt stage for mask alignment. According to claim 1,
The Z / Tilt flexure,
Constrained the degree of freedom in the XY plane direction of the platform, and configured to allow only Z-axis movement and θx and θy direction tilting,
Z/Tilt stage for mask alignment. According to claim 1,
The Z-axis linear stage,
Further comprising a local sensor for measuring the position and displacement of the Z-axis linear stage,
Z/Tilt stage for mask alignment. According to claim 1,
Further comprising a global sensor for measuring the position and displacement of the platform,
Z/Tilt stage for mask alignment. As a Z / Tilt stage control system for mask alignment,
controller;
one or more Z-axis linear stages for moving and tilting the platform; and
Z/Tilt flexures configured to be one or more elastic deformations configured to guide movement and tilting of the platform;
The Z-axis linear stage:
A body, a Z-axis guide flexure and a driving unit configured to be elastically deformed to limit outward transfer of the Z-axis linear stage in the Z-axis direction,
The drive unit applies a driving force to the Z-axis linear stage,
The Z-axis guide flexure guides the Z-axis linear stage to be transported only in the Z-axis direction.
Z/Tilt stage control system for mask alignment. According to claim 7,
The Z-axis guide flexures are disposed in pairs above and below the main body, and guide the Z-axis linear stage by sharing the same Z-axis and deforming themselves when a driving force is applied.
Z/Tilt stage control system for mask alignment. The method of claim 7, further comprising a driving force coupling flexures (force coupling flexures),
The driving force coupling flexure,
Transmitting only the driving force in the Z-axis direction of the Z-axis linear stage to the platform through deformation of the driving force coupling flexure itself;
The one or more Z / Tilt flexures,
Constraining the degree of freedom of the platform in the XY plane direction and allowing only Z-axis direction transfer and θx and θy direction tilting operations,
Z/Tilt stage control system for mask alignment. According to claim 7,
The Z-axis linear stage further includes a local sensor,
The local sensor measures the position and displacement of the Z-axis linear stage and provides it to the controller;
The controller controls the Z-axis linear stage by calculating the position of the platform using the position and displacement of the Z-axis linear stage provided from the local sensor.
Z/Tilt stage control system for mask alignment. According to claim 7,
Further comprising a global sensor,
The global sensor measures the position and displacement of the platform and provides it to the controller;
The controller directly controls the position of the platform using the position and displacement of the platform provided from the global sensor.
Z/Tilt stage control system for mask alignment.

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