阅读说明：本技术 交接力测量装置及方法、光刻机 (Cross-linking force measuring device and method and photoetching machine ) 是由 刘月 张阔峰 陈还 牛增欣 周美君 于 2019-11-28 设计创作，主要内容包括：本发明提供一种交接力测量装置及方法、光刻机,通过测力单元测得工件在交接过程中的受力情况并以信号形式输出至反馈控制单元,通过所述反馈控制单元将信号分析处理后反馈至所述工件承载单元或所述工件传输单元,以控制工件的传输和吸附,进而减少交接过程中工件的变形,提高工件的交接精度。(The invention provides a handover force measuring device and method and a photoetching machine, wherein the stress condition of a workpiece in the handover process is measured by a force measuring unit and is output to a feedback control unit in a signal form, and the signal is analyzed and processed by the feedback control unit and then fed back to a workpiece bearing unit or a workpiece transmission unit so as to control the transmission and adsorption of the workpiece, thereby reducing the deformation of the workpiece in the handover process and improving the handover precision of the workpiece.)

1. A handover force measurement device, comprising:

the workpiece bearing unit is used for bearing a workpiece;

the workpiece transmission unit is used for transmitting the workpiece to the workpiece bearing unit to realize the connection of the workpiece;

the force measuring unit is arranged on the workpiece or the workpiece bearing unit and is used for measuring the stress of the workpiece or the workpiece bearing unit in the workpiece handover process and outputting the stress in a signal form;

and the feedback control unit is in signal connection with the workpiece bearing unit, the force measuring unit and the workpiece transmission unit, and is used for receiving the signal output by the force measuring unit, analyzing and processing the signal and feeding the signal back to the workpiece bearing unit or the workpiece transmission unit.

2. The interface force measurement device of claim 1, wherein the load cell comprises a wafer-type pressure sensor.

3. The interface force measurement device of claim 1, wherein the workpiece is a reticle or a silicon wafer.

4. The handover force measurement device of claim 1, wherein the workpiece support unit is a mask stage or a stage having an adsorption capability.

5. The interface force measurement device of claim 1, wherein the workpiece transfer unit is a swap hand or a robot blade fork.

6. The handover force measuring device of claim 1, wherein a first controller is provided on the workpiece transfer unit to control transfer parameters of the workpiece.

7. The interface force measurement device of claim 6, wherein the workpiece transport parameters comprise velocity, acceleration, and jerk of a workpiece transport.

8. The handover force measurement device of claim 1, wherein a second controller is provided on the workpiece support unit to control a suction parameter of the workpiece.

9. The interface force measurement device of claim 8, wherein the suction parameter comprises a pressure of a suction vacuum.

10. The interface force measuring device of claim 1, wherein the interface force measuring device is applied in a mask transfer subsystem and a mask stage interface process of a lithography machine or a pre-alignment process of a silicon wafer transfer subsystem.

11. A lithography machine comprising the interface force measuring device according to any one of claims 1 to 10.

12. A method of handover force measurement, comprising:

the workpiece transmission unit transmits the workpiece to the workpiece bearing unit;

the force measuring unit measures the stress of the workpiece or the workpiece bearing unit and outputs the stress in a signal form;

and the feedback control unit receives the signal output by the force measuring unit, analyzes and processes the signal and feeds the signal back to the workpiece bearing unit or the workpiece transmission unit.

13. The method of claim 12, wherein the force measuring unit measures an impact force of the workpiece transfer unit on the workpiece carrier unit when the workpiece transfer unit is handed over to the workpiece carrier unit.

14. The method of measuring a transfer force according to claim 13, wherein a first controller is provided on the workpiece transfer unit to control transfer parameters of the workpiece, the method further comprising:

the workpiece transmission unit judges the relation between the impact force of the workpiece bearing unit and a first set value according to the feedback information of the feedback control unit, and the first controller adjusts the transmission parameters of the workpiece according to the judgment result.

15. The method according to claim 12, wherein the force measuring unit measures an adsorption force of the workpiece carrying unit to the workpiece when the workpiece transfer unit and the workpiece carrying unit perform the workpiece transfer.

16. The method of claim 15, wherein the workpiece carrier unit is provided with a second controller to control a suction parameter of the workpiece, the method further comprising:

the workpiece bearing unit judges the relation between the adsorption force borne by the workpiece and a second set value according to the feedback information of the feedback control unit, and the second controller adjusts the adsorption parameter of the workpiece according to the judgment result.

Technical Field

The invention relates to a lithography device, in particular to a device and a method for measuring a handover force in a mask or silicon wafer handover process and a lithography machine.

Background

When the photoetching machine works, in a mask or silicon wafer transmission subsystem, the mask or the silicon wafer needs to be quickly, accurately and reliably handed over from one station to another station. In order to ensure the handover precision of the mask plate or the silicon wafer, the deformation of the mask plate or the silicon wafer during handover is required not to be too large, so that the stress condition of the mask plate or the silicon wafer during handover needs to be measured and analyzed. At present, in the transmission process, no device for measuring the transmission relay exists, and the requirement cannot be met only by performing theoretical speed planning or empirical control on a transmission structure.

Specifically, in the mask transmission subsystem, the exchange manipulator module is used for executing the handover operation of the mask platform and the mask on the pick-and-place manipulator, and an adsorption force and a handover impact force exist during the adsorption and handover of the mask. As shown in fig. 1, the elevating shaft on the side of the plate changer 1 moves from the Home position to the LPA1 position at a high speed, and then moves from the LPA1 position to the LPA2 position, i.e., the position to be connected to the mask stage 3, at the lowest speed. At the moment of connection with the mask stage 3, although the reticle 2 is driven by the reticle changer 1 to move at a low speed, the reticle changer 1 still generates transient impact force on the mask stage 3. The servo force when the mask stage 3 is stable can be expressed as a sine wave load F ═ a × sin (ω t), where ω is the servo bandwidth frequency and a is the servo force peak; therefore, the impact force is less than or equal to A when the exchange plate 1 is connected with the mask table. Further, the reticle 2 is also attracted by the reticle changer 1 and the reticle stage 3. At present, a device capable of measuring the handing-over impact force and the adsorption force of the exchange plate hand and the mask stage does not exist, the design requirements are met only by performing theoretical planning on the vertical motion of the exchange plate hand and optimizing the structure of the mask stage, and the handing-over force cannot be intuitively and clearly subjected to feedback analysis by the mode.

In the silicon wafer transmission subsystem, the pre-alignment module and the mechanical arm wafer fork generate adsorption force on the silicon wafer, and the adsorption force can cause the silicon wafer to deform. In order to prevent the deformation of the silicon wafer from being too large, the silicon wafer is stable when being adsorbed, so that the adsorption force value needs to be known. The existing method only obtains the adsorption force by determining the adsorption air pressure, and the adsorption force cannot be clearly obtained by the method.

Disclosure of Invention

The invention aims to provide a device and a method for measuring a handing-over force and a photoetching machine, which are used for adjusting the transmission and the adsorption of a workpiece by measuring the stress of the workpiece in the handing-over process, thereby reducing the deformation of the workpiece in the handing-over process and improving the handing-over precision of the workpiece.

In order to achieve the above object, the present invention provides a handover force measuring apparatus including:

the workpiece transmission unit is used for transmitting the workpiece to the workpiece bearing unit to realize the connection of the workpiece;

the force measuring unit is arranged on the workpiece or the workpiece bearing unit and is used for measuring the stress of the workpiece or the workpiece bearing unit in the workpiece handover process and outputting the stress in a signal form;

and the feedback control unit is in signal connection with the workpiece bearing unit, the force measuring unit and the workpiece transmission unit, and is used for receiving the signal output by the force measuring unit, analyzing and processing the signal and feeding the signal back to the workpiece bearing unit or the workpiece transmission unit.

Optionally, the force measuring unit comprises a laminar pressure sensor.

Optionally, the workpiece is a mask or a silicon wafer.

Optionally, the workpiece carrying unit is a mask stage or a stage with an adsorption capability.

Optionally, the workpiece transmission unit is an exchange plate hand or a manipulator piece fork.

Optionally, a first controller is arranged on the workpiece transmission unit to control transmission parameters of the workpiece.

Optionally, the workpiece transfer parameters include speed, acceleration and jerk of workpiece transfer.

Optionally, a second controller is arranged on the workpiece carrying unit to control the adsorption parameters of the workpiece.

Optionally, the adsorption parameter comprises a pressure of an adsorption vacuum.

Optionally, the handover force measuring device is applied to a handover process between a mask transmission subsystem and a mask stage of a lithography machine or a pre-alignment process in a silicon wafer transmission subsystem.

Further, the invention also provides a lithography machine comprising the handover force measuring device.

Accordingly, the present invention provides a method for measuring handover force, comprising:

the workpiece transmission unit transmits the workpiece to the workpiece bearing unit;

the force measuring unit measures the stress of the workpiece or the workpiece bearing unit and outputs the stress in a signal form;

and the feedback control unit receives the signal output by the force measuring unit, analyzes and processes the signal and feeds the signal back to the workpiece bearing unit or the workpiece transmission unit.

Optionally, the force measuring unit measures an impact force of the workpiece transmission unit on the workpiece bearing unit when the workpiece transmission unit and the workpiece bearing unit perform workpiece handover.

Optionally, a first controller is disposed on the workpiece transfer unit to control transfer parameters of the workpiece, and the method for measuring the transfer force further includes:

the workpiece transmission unit judges the relation between the impact force of the workpiece bearing unit and a first set value according to the feedback information of the feedback control unit, and the first controller adjusts the transmission parameters of the workpiece according to the judgment result.

Optionally, the force measuring unit measures an adsorption force of the workpiece bearing unit to the workpiece when the workpiece transmission unit and the workpiece bearing unit perform workpiece handover.

Optionally, the workpiece carrying unit is provided with a second controller to control an adsorption parameter of the workpiece, and the handover force measuring method further includes:

the workpiece bearing unit judges the relation between the adsorption force borne by the workpiece and a second set value according to the feedback information of the feedback control unit, and the second controller adjusts the adsorption parameter of the workpiece according to the judgment result.

In summary, the stress condition of the workpiece in the handover process is measured by the force measuring unit and is output to the feedback control unit in the form of a signal, and the signal is analyzed and processed by the feedback control unit and then fed back to the workpiece bearing unit or the workpiece transmission unit to control the stress of the workpiece in the handover process, so that the deformation of the workpiece during handover is reduced, and the handover precision of the workpiece is further improved.

Drawings

FIG. 1 is a schematic diagram of a mask handoff process in a mask transfer subsystem;

fig. 2 is a block diagram of a cross-over force measuring device according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a handover force measuring apparatus according to an embodiment of the present invention;

fig. 4 is a schematic measurement diagram of a handover force measuring apparatus according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a second exemplary embodiment of an interface force measuring device;

fig. 6 is a schematic measurement diagram of a second embodiment of the present invention;

fig. 7 is a schematic structural diagram of a handover force measuring apparatus according to a third embodiment of the present invention.

Detailed Description

The present invention will be described in more detail with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description and drawings, it being understood, however, that the concepts of the present invention may be embodied in many different forms and should not be construed as limited to the specific embodiments set forth herein. The drawings are in simplified form and are not to scale, but are provided for convenience and clarity in describing embodiments of the invention.

The terms "first," "second," and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other sequences than described or illustrated herein. Similarly, if the method described herein comprises a series of steps, the order in which these steps are presented herein is not necessarily the only order in which these steps may be performed, and some of the described steps may be omitted and/or some other steps not described herein may be added to the method. Although elements in one drawing may be readily identified as such in other drawings, the present disclosure does not identify each element as being identical to each other in every drawing for clarity of description.

Example one

Fig. 2 is a block diagram of a cross-over force measuring device according to this embodiment. As shown in fig. 2, the handover force measuring apparatus provided in this embodiment includes: a workpiece carrying unit 30 for carrying a workpiece; the workpiece transmission unit 10 is used for transmitting the workpiece to the workpiece bearing unit 30 to realize the transfer of the workpiece; the force measuring unit 20 is arranged on the workpiece bearing unit 30 and used for measuring the stress of the workpiece or the workpiece bearing unit 30 in the workpiece transfer process and outputting the stress in the form of signals; and the feedback control unit 40 is in signal connection with the workpiece carrying unit 30, the force measuring unit 20 and the workpiece transmission unit 10, and is used for receiving the signal output by the force measuring unit 20, analyzing and processing the signal, and feeding the signal back to the workpiece carrying unit 30 and/or the workpiece transmission unit 10.

The workpiece may be a reticle or a silicon wafer. The workpiece transmission unit 10 may be an exchange pallet or a robot blade fork, and the workpiece transmission unit 10 is provided with a first controller 11 for controlling transmission parameters 12 of the workpiece, where the transmission parameters include a speed (v), an acceleration (a), and a jerk (jerk) of the workpiece. The workpiece bearing unit 30 may be a mask stage or an adsorption platform with a certain adsorption capacity, and is used for bearing a mask or adsorbing a silicon wafer, a second controller 31 is disposed on the workpiece bearing unit 30 to control an adsorption parameter 32 of a workpiece, and the adsorption parameter 32 includes a pressure of adsorption vacuum. The force measuring unit 20 includes a sheet-type sensor, such as a sheet-type pressure sensor, and can be adhered to the workpiece or the workpiece carrying unit 30 for measuring the stress of the workpiece or the workpiece carrying unit 30 during the transfer of the workpiece, and outputting the measured stress of the workpiece or the workpiece carrying unit 30 to the feedback control unit 40 in the form of a signal. The feedback control unit 40 is in signal connection with the workpiece carrying unit 30, the force measuring unit 20 and the workpiece transmission unit 10, receives the signal output by the force measuring unit 20, analyzes and processes the signal, and feeds the signal back to the workpiece carrying unit 30 and/or the workpiece transmission unit 30. The workpiece transmission unit 10 correspondingly adjusts the transmission parameters 12 of the workpiece through the first controller 11 according to the feedback of the feedback control unit 40, and the workpiece bearing unit 30 correspondingly adjusts the absorption parameters 32 of the workpiece bearing unit 30 through the second controller 31 according to the feedback of the feedback control unit 40.

The measurement device and the measurement method for the cross-over force provided by this embodiment will be described below by taking the process of the cross-over between the mask transmission subsystem and the mask stage of the lithography machine as an example, where the cross-over force measured by the cross-over force measurement device in this embodiment is the impact force of the mask plate on the mask stage during the process of the cross-over between the mask transmission subsystem and the mask stage. Fig. 3 is a schematic structural diagram of the handover force measuring apparatus according to the present embodiment. As shown in fig. 3, in the present embodiment, the workpiece 50 is a mask, the workpiece support unit 30 is a mask stage, and the Chuck (Chuck)33 is disposed on the mask stage; the force measuring unit 20 is a thin-sheet type pressure sensor and is arranged on a chuck 31 of the mask table; the workpiece transmission unit 10 is a reticle exchange hand, the reticle exchange hand adsorbs a reticle to vertically move to a mask table, the reticle is released to a chuck 33 of the mask table, a thin sheet type pressure sensor arranged on the chuck 33 is triggered, the pressure sensor measures a numerical value of impact force when the reticle exchange hand is connected with the mask table, the numerical value is converted into a signal and is output to the feedback control unit 40 (not shown in the figure), the feedback control unit 40 analyzes and processes the signal and then feeds the signal back to the reticle exchange hand, a first controller arranged on the reticle exchange hand adjusts transmission parameters of the reticle correspondingly according to feedback of the feedback control unit 40, and the transmission parameters, namely the speed parameters of the reticle, comprise speed (v), acceleration (a) and jerk (jerk). In this embodiment, the feedback control unit 40 may be a part of the mask transmission subsystem, or may exist separately.

Fig. 4 is a measurement schematic diagram of the handover force measurement apparatus according to the present embodiment. As shown in fig. 4, firstly, the reticle is adsorbed by the reticle hand and moved to the home position, the first controller on the reticle hand sets the transmission parameters, the reticle is adsorbed by the reticle hand and moved to the reticle stage, the reticle is released to the chuck, the thin-sheet pressure sensor is triggered, and the value of the cross-over force is measured. The numerical value of the handover force is transmitted to a feedback control unit, the feedback control unit sends a signal to a first controller on a handover plate to judge the relation between the handover force F1 and a first set value (the servo force peak value A of the mask table), and if F1 is less than or equal to A, the handover is finished; if F1 is larger than A, the exchange plate hand returns to the home position, the first controller adjusts the transmission parameters, and then the exchange plate hand moves to the mask stage to measure and judge the handover force until the measured handover force meets the condition that F is less than or equal to A. Therefore, finite element simulation analysis can be carried out on the mask plate by measuring the numerical value of the intersection force, and the deformation and the stress of the mask plate can be obtained. And for the stress condition of the mask plate in the whole process of moving the exchange plate hand from the home position to the mask table, dynamic analysis can be performed, the displacement response of the mask plate at different stations is analyzed, and the handover precision of the mask plate can be further improved by utilizing a simulation analysis result.

In the actual handover process, the exchange plate hand adsorbs the mask to move to the home position, a first controller on the exchange plate hand is set to set transmission parameters according to a simulation result, the exchange plate hand adsorbs the mask to move to the mask table, the mask is released to the chuck, the thin sheet type pressure sensor is triggered, and a handover force value is measured. The numerical value of the handover force is transmitted to a feedback control unit 40, the feedback control unit 40 sends a signal to a first controller on a handover plate to judge the relation between the handover force F and the servo force peak value A of the mask table, and if F is less than or equal to A, the handover is finished; if F is larger than A, the switching edition hand returns to the home position, and the first controller on the switching edition hand sends out an error signal to wait for a further instruction of the feedback control system.

In addition, the sheet-type pressure sensor in the embodiment can be adhered to different areas according to actual requirements, and the measuring method of the handover force can be expanded to measure the stress condition of the whole process of handing over the mask plate to the mask table by the exchange plate.

Furthermore, the invention also provides a photoetching machine, which comprises the above-mentioned connecting force measuring device.

Example two

The embodiment provides a device and a method for measuring a cross-over force, which are applied to a pre-alignment process in a silicon wafer transmission subsystem.

Specifically, fig. 5 is a schematic structural diagram of the handover force measuring apparatus provided in this embodiment. As shown in fig. 5, the workpiece 50 in the intersection force measuring device is a silicon wafer, the workpiece supporting unit 30 is a pre-alignment module in the silicon wafer transmission subsystem, specifically, the silicon wafer is adsorbed on the silicon wafer storage structure 34 of the pre-alignment module, and a second controller arranged in the pre-alignment module controls the adsorption force of the silicon wafer storage structure 34 on the silicon wafer by controlling the vacuum pressure in the pre-alignment module. The workpiece transmission unit 10 is a robot blade fork (not shown in the figure), the measurement unit 20 is a sheet sensor fixed on the lower surface of the silicon wafer, for example, a sheet pressure sensor, which can be fixed on the lower surface of the silicon wafer by adhesion, and measures during adsorption, and transmits the obtained adsorption force to the feedback control unit 40 in a signal form, and the feedback control unit 40 analyzes and processes the measured adsorption force and feeds the processed adsorption force back to the second controller, and correspondingly adjusts the adsorption force by controlling the vacuum pressure. In this embodiment, the feedback control unit 40 may be a part of a silicon chip transmission subsystem, or may exist alone.

Fig. 6 is a measurement schematic diagram of the handover force measurement apparatus according to the present embodiment. As shown in fig. 6, when the wafer fork of the robot arm adsorbs the silicon wafer and moves to the pre-alignment handover station, the silicon wafer storage structure of the pre-alignment module has set adsorption pressure, and then handover adsorption is performed, the wafer pressure sensor measures the adsorption force value of the silicon wafer during handover and feeds the value back to the feedback control unit to determine whether the second set value (adsorption force index B) is met, and if F2 is greater than or equal to B, handover is finished; if F2 is less than B, the mechanical arm piece fork returns to the home position, the second controller adjusts the adsorption parameters of the pre-alignment module, the mechanical arm piece fork adsorbs the silicon wafer and returns to the pre-alignment handover station for handover adsorption until the adsorption force F2 is measured to be more than or equal to B. Therefore, the pressure of the adsorption vacuum can be adjusted through the second controller, and finite element simulation analysis is carried out on the silicon wafer to obtain the deformation and the stress of the silicon wafer. The simulation analysis result is utilized to further improve the handover precision of the silicon chip.

EXAMPLE III

The embodiment provides a handover force measuring device, which is applied to a pre-alignment process in a silicon wafer transmission subsystem, wherein handover force measured by the handover force measuring device in the embodiment refers to the adsorption force of a pre-alignment module on a silicon wafer in the pre-alignment process in the silicon wafer transmission subsystem. In this embodiment, the workpiece 50 in the intersection force measuring apparatus is a silicon wafer, and the workpiece carrying unit 30 is a pre-alignment module in a silicon wafer transmission subsystem, different from the second embodiment, in this embodiment, the silicon wafer is adsorbed on a temperature control platform (TSU)35 in the pre-alignment module after being intersected. In the silicon wafer transmission subsystem, the temperature control platform 35 plays a role in controlling the temperature of the silicon wafer in the pre-alignment module, as shown in fig. 7, the middle region of the silicon wafer is supported by the pre-alignment module to adsorb the silicon wafer, i.e., an adsorption force F3 is generated on the silicon wafer, a gas film with a certain thickness is formed between the temperature control platform 35 and the silicon wafer, an upward thrust force F4 is generated on the silicon wafer, the silicon wafer deforms under the action of forces bearing opposite directions of the adsorption force F3 and the thrust force F4, and the stress regions are different, so that the stress conditions of different regions of the silicon wafer need to be analyzed to obtain the deformation conditions of the silicon wafer. In the embodiment, the force measuring unit 20 is arranged on the lower surface of the silicon wafer to obtain the bearing force of the silicon wafer. The method of embodiment 2 can be adopted to stick a corresponding sensor on the lower surface of the silicon wafer to measure and feed back the stress condition of the silicon wafer, so as to adjust the adsorption force and the thrust force, further obtain the deformation of the silicon wafer through simulation analysis, and provide data reference for optimizing the temperature control platform. In this embodiment, the force measuring units 20 may be located on the lower surface of the silicon wafer corresponding to the pre-alignment module support region, or located on the lower surface of the silicon wafer corresponding to the region outside the pre-alignment module support region, and the number and positions of the force measuring units 20 may be set according to actual measurement requirements.

In summary, the present invention provides an apparatus and a method for measuring a handover force, and a lithography machine. Wherein, handing-over force measuring device includes: the workpiece bearing unit is used for bearing a workpiece; the workpiece transmission unit is used for transmitting the workpiece to the workpiece bearing unit to realize the connection of the workpiece; the force measuring unit is arranged on the workpiece or the workpiece bearing unit and used for measuring the stress of the workpiece or the workpiece bearing unit in the workpiece handover process and outputting the stress in a signal form; and the feedback control unit is in signal connection with the workpiece bearing unit, the force measuring unit and the workpiece transmission unit, and is used for receiving the signal output by the force measuring unit, analyzing and processing the signal and feeding the signal back to the workpiece bearing unit and/or the workpiece transmission unit. The handover force measuring method includes: the workpiece transmission unit transmits the workpiece to the workpiece bearing unit; the force measuring unit measures the stress of the workpiece or the workpiece bearing unit and outputs the stress in a signal form; the feedback control unit receives the signal output by the force measuring unit, analyzes and processes the signal and feeds the signal back to the workpiece bearing unit or the workpiece transmission unit. According to the invention, the stress condition of the workpiece in the handover process is measured by the force measuring unit and is output to the feedback control unit in a signal form, and the signal is analyzed and processed by the feedback control unit and then fed back to the workpiece bearing unit or the workpiece transmission unit so as to control the transmission and adsorption of the workpiece, thereby reducing the deformation of the workpiece in the handover process and improving the handover precision of the workpiece.

It should be noted that, in the present specification, all the embodiments are described in a related manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the structural embodiment, since it is substantially similar to the method embodiment, the description is relatively simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.