Patent Publication Number: US-2022238329-A1

Title: Semiconductor lithography apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of International Patent Application No. PCT/CN2021/100906 filed on Jun. 18, 2021, which claims priority to Chinese Patent Application No. 202110118289.7, filed on Jan. 28, 2021. The above-referenced patent applications are incorporated herein by reference in their entirety. 
    
    
     TECHNICAL FIELD 
     The present application relates to the field of semiconductor technologies, and in particular, relates to a semiconductor lithography apparatus. 
     BACKGROUND 
     A photomask is a template for manufacturing a circuit of a chip. Once the photomask is contaminated, products will be greatly affected. A semiconductor device has a machine station in which a device for detecting particle contamination of the photomask is disposed. The particle contamination of the photomask occurs at an extremely high frequency, which seriously affects the efficiency of the machine station of the semiconductor device. Meanwhile, the machine station checks the particle contamination on a surface of the photomask only regularly instead of all the time, or check it after an exposure process, which results in a problem that a whole batch of products often needs to be reprocessed. If the particle contamination cannot be detected due to a design defect of a detection device per se, product scrap will be caused, which will have a very serious impact on a yield and a cost. 
     For a semiconductor lithography apparatus in the related art, a photomask conveying process in the semiconductor lithography apparatus will involve a plurality of parts and a large number of mechanical transmission components. In this way, some contaminating particles will be generated during the conveying process and fall on the surface of the photomask to cause contamination. In the related art, the surface of the photomask is cleaned by introducing a cleaning gas towards the surface of the photomask from an upper side of the photomask in the semiconductor lithography apparatus and by blowing the cleaning gas to the surface of the photomask from the top down. However, if the cleaning gas is not clean or a gas introducing pipeline is worn, or if particles are produced due to the inner wear of the semiconductor device in a few days, the particles will, on the contrary, be blown by the cleaning gas from the top down to fall on the surface of the photomask, leading to low efficiency in treating the photomask contamination. 
     SUMMARY 
     The present application provides a semiconductor lithography apparatus. 
     The semiconductor lithography apparatus according to an embodiment of the present application includes: a photomask conveying device and a photomask clamping device connected to the photomask conveying device, wherein the photomask clamping device is configured to carry a photomask; and a photomask-cleaning gas jet device connected to the photomask clamping device for jetting a gas to an upper side of the photomask so as to prevent particulate matters from falling on a surface of the photomask. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic diagram of a connecting structure between a photomask-cleaning gas jet device and a photomask clamping device in a semiconductor lithography apparatus according to an embodiment of the present application; 
         FIG. 2  is a schematic top view of a connecting structure between the photomask-cleaning gas jet device and the photomask clamping device in the semiconductor lithography apparatus according to an embodiment of the present application; 
         FIG. 3  is a top view of a photomask-cleaning gas jet device of the semiconductor lithography apparatus according to an embodiment of the present application; and 
         FIG. 4  is a side view of a photomask-cleaning gas jet device of the semiconductor lithography apparatus according to an embodiment of the present application. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     A semiconductor lithography apparatus according to embodiments of the present application will be described below with reference to the accompanying drawings. The semiconductor lithography apparatus when in use may convey and utilize a photomask  200 . For example, the semiconductor lithography apparatus according to the embodiments of the present application may be an exposure machine or a lithography machine, which can avoid particle contamination of the photomask  200  during the process of conveying or utilizing the photomask  200 , so as to increase an application efficiency of the photomask  200 , improve a product yield and reduce a cost. 
     The semiconductor lithography apparatus according to the embodiments of the present application may include a photomask conveying device, a photomask clamping device, and a photomask-cleaning gas jet device  100 . 
     The photomask conveying device is configured to convey the photomask  200 . For example, the photomask conveying device may include a robotic arm, by which the photomask  200  may be conveyed to different parts. The photomask clamping device is connected with the photomask conveying device for clamping and carrying the photomask  200 . For example, the photomask clamping device may be connected to an end of the photomask conveying device, the latter is moved to drive the photomask clamping device to move, such that the photomask  200  may be transferred among different positions. 
     The photomask-cleaning gas-jet device  100  is connected to the photomask clamping device. When carrying the photomask  200  by the photomask clamping device, the photomask-cleaning gas-jet device  100  may be configured to blow a gas towards an upper side of the photomask  200 , to prevent contamination caused by particulate matters falling on a surface of the photomask  200 . Specifically, during the use of the semiconductor lithography apparatus, for example, during the process of conveying the photomask  200 , internal transmission components of the semiconductor lithography apparatus wear out and produce particulate matters. The photomask-cleaning gas-jet device  100  may be configured to jet the gas from the bottom up, not only to prevent the particulate matters from being blown downward to the surface of the photomask  200 , but also to blow the falling particulate matters upward to prevent them from falling on the surface of the photomask. Moreover, when a cleaning gas contains contaminating particulate matters or the jetted gas passes through a pipe having particulate matters inside, the particulate matters may also be prevented from falling on the surface of the photomask  200 , since the cleaning gas is jetted upward. 
     As a result, by providing the photomask-cleaning gas jet device  100  in the semiconductor lithography apparatus according to the embodiments of the present application, the photomask-cleaning gas jet device  100  may jet the gas from the bottom up to prevent the particulate matters from falling on the surface of the photomask  200 , thereby reducing the contamination of the photomask  200 , increasing the utilization rate of the photomask  200 , and further improving the product yield and reducing the cost. 
     For a gas jet direction of the photomask-cleaning gas jet device  100 , the photomask-cleaning gas jet device  100  may jet a gas upward inclinedly towards the photomask  200 , which may not only prevent the particulate matters from falling on the surface of the photomask  200 , but also allow the particulate matters to inclinedly move following the gas by means of inclined gas-jetting and to be jetted out of a corresponding area above the surface of the photomask  200 , so as to further prevent the contamination caused by the particulate matters falling on the surface of the photomask  200 . Optionally, an inclination angle between the gas jet direction of the photomask-cleaning gas-jet device  100  and the surface of the photomask  200  may range from 25° to 75°, for example, the inclination angle between the gas jet direction of the photomask-cleaning gas-jet device  100  and the surface of the photomask  200  may be 60°. 
     In some embodiments of the present application, the photomask-cleaning gas jet device  100  may include a gas jet pipe  1  and a nozzle  15  communicated with the gas jet pipe  1 , where the gas jet pipe  1  is connected to a gas source of the cleaning gas jetted by the photomask-cleaning gas-jet device, such that delivering the cleaning gas may be accomplished. The nozzle  15  is configured to jet the cleaning gas, that is, the cleaning gas delivered by the gas jet pipe  1  is jetted by the nozzle  15 , by which a jet direction of the cleaning gas may be defined. 
     One end of the nozzle  15  is connected to the gas jet pipe  1 , and the other end of the nozzle  15  extends upward inclinedly towards a position where the photomask  200  is disposed, such that the gas jet direction of the nozzle  15  is inclined upward with respect to the surface of the photomask  200 . In other words, the nozzle  15  are disposed inclinedly with respect to the surface of the photomask  200  and extend upward. In this way, the cleaning gas may be jetted upward inclinedly by the nozzle  15  to form a cleaning area above the photomask  200  for preventing the particulate matters from falling on the photomask  200 . 
     Optionally, as shown in  FIG. 4 , an inclination angle a between the gas-jet direction of the nozzle  15  and the surface of the photomask  200  ranges from 25° to 75°. For example, the inclination angle a between the gas jet direction of the nozzle  15  and the surface of the photomask  200  may be 30°, 40°, or 50°. As a result, the particulate matters may be not only blown upward and prevented from falling on the surface of the photomask  200 , but also blown out of the corresponding area above the photomask  200 . Preferably, the inclination angle a between the gas jet direction of the nozzle  15  and the surface of the photomask  200  is 60°. 
     In an example shown in  FIG. 4 , when the nozzle  15  is disposed inclinedly and the photomask  200  is carried on the photomask clamping device, an included angle between the nozzle  15  and a plane, in which the photomask  200  is disposed, ranges from 25° to 75°. That is, the inclination angle of the nozzle  15  with respect to the surface of the photomask  200  ranges from 25° to 75°, and preferably the inclination angle of the nozzle  15  with respect to the surface of the photomask  200  is 60°. 
     In some examples of the present application, the photomask-cleaning gas-jet device  100  may jet the gas to at least two opposite sides of the photomask  200 , such that the cleaning gas may form a convective area above the photomask  200  since the cleaning gas on each side of the photomask  200  is jetted upward inclinedly with respect to the surface of the photomask  200 . As a result, the flow mildness of the cleaning gases may be improved, and the particulate matters may be further prevented from falling on the surface of the photomask  200 . 
     Specifically, at least two opposite sides of the photomask  200  may be provided with the nozzles  15  to form the convective gas jet area above the photomask  200 . In other words, the nozzles  15  may be disposed outside the photomask  200 . That is, the nozzles  15  may be disposed on an outer side of an outer edge of the photomask  200 , and extend upward inclinedly towards a position where the photomask  200  is disposed, so as to produce the cleaning gas inclining upward. Moreover, the nozzles  15  may be formed at least on both sides of the photomask  200 . For example, as shown in  FIGS. 1 to 4 , the nozzles  15  may be formed on left and right sides of the photomask  200  and at the same time on a front side of the photomask  200 , such that when the nozzles  15  jet the gas, a convective gas jet area may be formed above the photomask  200  to further prevent the particulate matters from falling on and contaminating the photomask  200 . 
     In some specific examples of the present application, the gas jet pipe  1  may include a first pipe  11 , a second pipe  12 , and a third pipe  13 . Ends of the first pipe  11  are connected with one end of the second pipe  12  and one end of the third pipe  13  on the same side, respectively. The second pipe  12  and the third pipe  13  are disposed on two opposite sides of the photomask  200  respectively; the first pipe  11 , the second pipe  12 , and the third pipe  13  surround the photomask  200 ; and the first pipe  11 , the second pipe  12  and the third pipe  13  are all provided with the nozzles  15 . 
     As shown in  FIGS. 2 and 4 , the second pipe  12 , the first pipe  11 , and the third pipe  13  are connected in sequence to partially surround the photomask  200 . Specifically, the first pipe  11  and the third pipe  13  are arranged in parallel and disposed outside two opposite sides of the photomask  200 ; ends of the first pipe  11  are connected to the second pipe  12  and the third pipe  13 , respectively; and the nozzles  15  are formed on the first pipe  11 , the second pipe  12 , and the third pipe  13 , such that cleaning gases may be jetted on at least two opposite sides of the photomask  200 , thereby forming the convective gas-jet area above the photomask  200 . 
     For the shape of the nozzle  15 , the nozzle  15  may be flat, and may extend along an extension direction of the gas jet pipe  1 . For example, the first pipe  11  may be provided with a first nozzle  15 , and the second pipe  12  may be provided with a second nozzle  15 ; and the third pipe  13  may be further provided with a third nozzle  15 . Moreover, one first nozzle  15  is provided and has a flat shape extending along a length direction of the first pipe  11 ; one second nozzle  15  may be provided and formed in a flat shape extending along a length direction of the second pipe  12 ; and one third nozzle  15  may be provided and formed in a flat shape extending along a length direction of the third pipe  13 . 
     Alternatively, the nozzle  15  may be formed in a hollow cylindrical structure, and a plurality of nozzles  15  may be provided and disposed at even intervals along the extension direction of the gas jet pipe  1 . In this way, the intensity of a gas flow jetted by the nozzles  15  may be enhanced, thereby blowing off the particulate matters. As shown in  FIG. 1 , a plurality of the nozzles  15  are provided and are disposed on the first pipe  11 , the second pipe  12  and the third pipe  13  at even intervals. 
     Optionally, both the second pipe  12  and the third pipe  13  are in communication with the first pipe  11 , and the gas jet pipe  1  further includes a fourth pipe  14 , which is in communication with the first pipe  11  and a gas source. As a result, the gas source may deliver the cleaning gas to the first pipe  11  through the fourth pipe  14 , and the cleaning gas flows to the second pipe  12  and the third pipe  13  respectively through the first pipe  11 , thereby facilitating the delivery of the cleaning gas and enabling the cleaning gas to be jetted out through the nozzles  15  on the first pipe  11 , the second pipe  12  and the third pipe  13 . 
     Further, the photomask conveying device includes a robotic conveying arm, in which the fourth pipe  14  is disposed. Specifically, the gas source may be disposed in a machine station of the semiconductor lithography apparatus; and the fourth pipe  14  is penetratively disposed in the robotic conveying arm to facilitate the connection between the fourth pipe  14  and the gas source. When the robotic conveying arm moves to transfer the photomask  200 , the fourth pipe  14  may move with the robotic conveying arm. As a result, during the process of moving the photomask  200 , the photomask-cleaning air-jet device  100  may also clean the photomask  200  to prevent the particulate matters from falling on the surface of the photomask  200 . Moreover, the fourth pipe  14  may also be protected by the robotic conveying arm. 
     In some embodiments of the present application, the photomask-cleaning gas jet device  100  further includes at least one control valve. The control valve is disposed on the gas jet pipe  1  for controlling on-off of the gas jet pipe  1 . As a result, the gas jetting of the nozzles  15  on the gas jet pipe  1  may be controlled by the control valve, so as to prevent the particulate matters from falling by jetting the gas when the photomask  200  is disposed on the photomask clamping device. The control valve may be provided as one or more in number. When a plurality of control valves are provided, the control valves may be disposed on different positions of the gas jet pipe  1 . In this way, the gas-jet pipe  1  may be divided into a plurality of sections, and the plurality of control valves control on/off of the plurality of sections of the gas jet pipe  1 , respectively, so as to control, by the control valves, different sections of the gas-jet pipe  1  to jet the gas. As a result, the different nozzles  15  of the gas jet pipe  1  may be controlled to jet the gas according to cleaning needs. 
     Optionally, three control valves may be provided and are disposed on the first pipe  11 , the second pipe  12  and the third pipe  13  respectively, so as to control the photomask-cleaning gas jet device  100  to jet the gas to different sides of the photomask  200 . Specifically, by the three control valves, the on/off of the first pipe  11 , the second pipe  12  and the third pipe  13  may be separately controlled to further control the gas jetting of the nozzles  15  on the first pipe  11 , the second pipe  12  and the third pipe  13 . By turning on and off different control valves, the nozzles  15  on the first pipe  11 , the second pipe  12 , and the third pipe  13  jet the gas or do not jet the gas. In this way, each control valve may be adjusted according to actual cleaning needs, such that the cleaning gas is jetted to different sides of the photomask  200  through the nozzles  15  to further prevent the contamination caused by the particulate matters. 
     In some embodiments of the present application, the photomask clamping device includes a clamping plate  2  for carrying and clamping the photomask  200 ; the clamping plate  2  is provided with a through hole penetrating in a thickness direction thereof; the photomask-cleaning gas jet device  100  is connected below the photomask clamping device; and the nozzle  15  is penetratively disposed in the through hole, which facilitates the connection of the photomask-cleaning gas jet device  100  with the photomask clamping device. As shown in  FIG. 1 , the photomask  200  is carried on a substantially middle position of the clamping plate  2 ; and a plurality of through holes are provided and are disposed on an area that surrounds and supports the photomask  200 . The photomask-cleaning gas-jet device  100  is provided with a plurality of nozzles  15 , which are disposed in a one-to-one correspondence with the plurality of through holes; and each of the nozzles  15  is correspondingly installed in the corresponding through hole such that the plurality of nozzles  15  may be disposed around the photomask  200 . The through holes penetrate through the clamping plate  2  along the thickness direction of the clamping plate  2 , the photomask-cleaning gas jet device  100  is disposed below the clamping plate  2 , and the nozzles  15  pass through the through holes so as to be exposed from a surface of the clamping plate  2 , thereby jetting the cleaning gas upward inclinedly towards a position where the photomask  200  is disposed. 
     Optionally, an upper surface of the nozzle  15  is flush with an upper surface of the clamping plate  2 . In this way, when the photomask  200  is carried on the clamping plate  2 , the upper surface of the nozzle  15  may be flush with the surface of the photomask  200 , such that the leaning gas may be jetted inclinedly towards the upper side of the photomask  200  when the nozzle  15  jet the gas. 
     Further, the clamping plate  2  is provided with a groove on the bottom thereof; the gas-jet pipe  1  is embedded in the groove; and the nozzle  15  is disposed in the through hole. As a result, by embedding the gas jet pipe  1  in the groove, the clamping plate  2  and the photomask-cleaning gas-jet device  100  may be fixedly connected to prevent the nozzle  15  from falling out of the through hole. Moreover, this structure is simple and the connection is convenient. 
     As shown in  FIG. 1 , the clamping plate  2  includes a first clamping and carrying portion  21  and a second clamping and carrying portion  22 , which are disposed oppositely at an interval, for fixing the photomask  200 . Specifically, the first clamping and carrying portion  21  and the second clamping and carrying portion  22  are disposed in parallel at an interval. The photomask  200  is carried between the first clamping and carrying portion  21  and the second clamping and carrying portion  22 . The clamping plate  2  further includes photomask-cleaning carrying portions  23 , which are configured to connect the photomask-cleaning gas jet device  100 . The photomask-cleaning carrying portions are disposed on outer sides of the first clamping and carrying portion and the second clamping and carrying portion, and the photomask-cleaning gas jet device  100  is connected to the photomask-cleaning carrying portions  23 , such that the photomask-cleaning gas-jet device  100  may be disposed around the photomask  200  to jet the gas upward inclinedly towards the photomask  200 . 
     Described above are merely preferred embodiments of the present application. It should be noted that for those of ordinary skills in the art, a number of improvements and modifications can be made without departing from the principle of the present application, and shall be construed as falling within the protection scope of the present application.