Device for the storage and use of at least one photomask for lithographic projection and method for using the device in an exposure installation

Abstract

The invention relates to a device for the storage of at least one photomask for lithographic projection and a method for using the device in an exposure installation. A container is suitable for receiving a photomask. The container has a housing, a closable opening device situated at the container housing and serving for the entry and issuing of the photomask, and one gas inlet opening arranged to purge the photomask. The invention also relates to a method for using the device in an exposure installation.

1 . A device for storage and use of at least one photomask for lithographic projection, the device comprising: 
 a container suitable for receiving a photomask, the container comprising a container housing and a closable opening device situated at the container housing and serving for the entry and issuing of the photomask, the container comprising at least one gas inlet opening arranged in such a way that, in the case of purging the photomask, a purge gas flushes around the photomask with a substantially laminar flow.    
   
   
       2 . The device according to  claim 1 , wherein the photomask comprises a transparent substrate, which is provided with a pattern of absorbent, partly absorbent, phase-shifting or reflective structure elements on its front side, and comprising a frame, which is arranged on the front side of the transparent substrate outside the pattern of absorbent, partly absorbent or phase-shifting structure elements, and comprises a protective film, which is arranged above the transparent substrate on the frame in order to protect the structure elements from particles in an at least partly closed-off volume.  
   
   
       3 . The device according to  claim 2 , wherein the protective film is permeable to gaseous substances of the purge gas toward the volume.  
   
   
       4 . The device according to  claim 2 , wherein the protective film is provided with one pinhole or a plurality of pinholes in order to enable a gas exchange between the volume and the region outside the volume.  
   
   
       5 . The device according to  claim 2 , wherein the frame is provided with one pinhole or a plurality of pinholes in order to enable a gas exchange between the volume and the region outside the volume.  
   
   
       6 . The device according to  claim 1 , wherein the container housing comprises an electrostatically dissipating coating.  
   
   
       7 . The device according to  claim 1 , wherein the container housing comprises a reticle holder in order to hold the photomask in a predetermined position.  
   
   
       8 . Device according to  claim 7 , wherein the closable opening is a bottom flap and comprises a reticle support in order to hold the photomask in a predetermined position.  
   
   
       9 . The device according to  claim 8 , wherein the gas inlet opening and the gas outlet opening are arranged on the bottom flap in a manner offset with respect to the photomask.  
   
   
       10 . The device according to  claim 1 , wherein the container comprises a handling flange suitable for transferring the photomask to an exposure apparatus by means of a mechanical interface.  
   
   
       11 . The device according to  claim 1 , wherein the container and the bottom flap correspond to an industry standard according to a SEMI standard.  
   
   
       12 . The device according to  claim 11 , wherein the mechanical interface corresponds to an industry standard according to a SEMI standard.  
   
   
       13 . A device for storage and use of at least one photomask for lithographic projection, the device comprising: 
 a container suitable for receiving a photomask, the container comprising a container housing and a closable opening device situated at the container housing and serving for the entry and issuing of the photomask, the container comprising at least one gas inlet opening arranged in such a way that, in the case of purging the photomask, a purge gas flushes around the photomask; and    a purge device comprising at least one gas feed line connected to the gas inlet opening, the purge device being suitable for purging the container with a purge gas in order to prevent crystallization on the photomask, and in which the container comprises a gas outlet opening and the purge device furthermore comprises at least one gas discharge line connected to the gas outlet opening.    
   
   
       14 . The device according to  claim 13 , wherein the purging device is connected to an adapter plate arranged below the bottom flap of the container, so that the gas feed line is connected to the gas inlet opening and the gas discharge line is connected to the gas outlet opening.  
   
   
       15 . The device according to  claim 14 , further comprising a holding frame suitable for receiving the container, said holding frame comprises fixings suitable for receiving the adapter plate.  
   
   
       16 . The device according to  claim 15 , wherein the fixings are embodied in screwable fashion in order to enable the adapter plate to be exchanged.  
   
   
       17 . The device according to  claim 14 , wherein the adapter plate is embodied in the holding frame as rack bottom on which the container with the photomask is placed and can be secured by means of a hinged mechanism.  
   
   
       18 . The device according to  claim 14 , wherein the positioning of the container in the holding frame is effected by means of the handling flange.  
   
   
       19 . The device according to  claim 14 , wherein the positioning of the photomask in the container is effected by means of constant contact pressure.  
   
   
       20 . The device according to  claim 17 , wherein the hinged mechanism is embodied in the form of a clip, which is fitted to the holding frame in a rotatable manner and can be pivoted into a receiving position and a holding position.  
   
   
       21 . A device for storage and use of at least one photomask for lithographic projection, the device comprising: 
 a container suitable for receiving a photomask, the container comprising a container housing and a closable opening device situated at the container housing and serving for the entry and issuing of the photomask, the container comprising at least one gas inlet opening arranged in such a way that, in the case of purging the photomask, a purge gas flushes around the photomask with a substantially laminar flow; and    a purge device comprising at least one gas feed line connected to the gas inlet opening, the purge device being suitable for purging the container with a purge gas in order to prevent crystallization on the photomask, and in which the container comprises a gas outlet opening and the purge device furthermore comprises at least one gas discharge line connected to the gas outlet opening, said purging device being arranged below the bottom flap of the container, so that the gas feed line is connected to the gas inlet opening and the gas discharge line is connected to the gas outlet opening.    
   
   
       22 . The device according to  claim 21 , wherein the purge device comprises a mixing device for purging with a plurality of gases, the mixing device comprising a T-piece and mixing valve in order to admix the plurality of gases in the desired mixing ratio.  
   
   
       23 . The device according to  claim 22 , wherein the purge device feeds a gas mixture for cleaning of organic contaminations as purge gas.  
   
   
       24 . The device according to  claim 23 , wherein the purge device feeds a nitrogen-ozone gas mixture.  
   
   
       25 . The device according to  claim 22 , wherein the purge device feeds a gas mixture for cleaning of inorganic contaminations as purge gas.  
   
   
       26 . The device according to  claim 25 , wherein the purge device feeds a nitrogen-argon gas mixture.  
   
   
       27 . The device according to  claim 22 , wherein the purge device feeds a nitrogen-hydrogen gas mixture.  
   
   
       28 . The device according to  claim 27 , wherein the purge device feeds a hydrogen-containing gas mixture.  
   
   
       29 . The device according to  claim 28 , wherein the gas mixture is a forming gas in which the hydrogen proportion is chosen below a flammability threshold.  
   
   
       30 . The device according to  claim 22 , wherein the purge device feeds a nitrogen-carbon dioxide gas mixture.  
   
   
       31 . The device according to  claim 21 , wherein the purge device controls the gas temperature and/or the gas partial pressures of the purge gas alongside the mixing ratios.  
   
   
       32 . The device according to  claim 21 , wherein the purge device feeds a gas mixture suitable for removing water from the surface of the photomask.  
   
   
       33 . The device according to  claim 32 , wherein the purge device feeds a nitrogen-oxygen gas mixture.  
   
   
       34 . The device according to  claim 32 , wherein the purge device feeds an air mixture from which water comprises been removed.  
   
   
       35 . A device for storage and use of at least one photomask for lithographic projection, the device comprising: 
 a container suitable for receiving a photomask, the container comprising a container housing and a closable opening device situated at the container housing and serving for the entry and issuing of the photomask, the container comprising at least one gas inlet opening arranged in such a way that, in the case of purging the photomask, a purge gas flushes around the photomask with a substantially laminar flow; and    a microwave source suitable for emitting microwave radiation comprising a specific wavelength and intensity from the side of the structure elements onto the photomask.    
   
   
       36 . The device according to  claim 35 , wherein the wavelength and/or intensity of the microwave radiation of the microwave source is chosen such that chemical bonds of impurities on the surface of the transparent substrate, in the volume between the surface of the transparent substrate and the protective film or on the surface of the protective film at least partly break up.  
   
   
       37 . The device according to  claim 36 , wherein the wavelength and/or intensity of the microwave radiation of the microwave source is furthermore chosen such that hydrogen-oxygen bonds in the impurities at least partly break up.  
   
   
       38 . The device according to  claim 37 , wherein the impurities comprise ammonium sulfate present in crystalline form on the surface of the transparent substrate, in the volume between the surface of the transparent substrate and the protective film or on the surface of the protective film.  
   
   
       39 . The device according to  claim 35 , wherein the wavelength of the microwave radiation of the microwave source is furthermore chosen such that it lies within a range in which the protective film is at least partly transparent to microwave radiation.  
   
   
       40 . The device according to  claim 39 , wherein the protective film comprises a Teflon-containing material.  
   
   
       41 . The device according to  claim 39 , wherein the frequency of the microwave radiation lies within the range of between 2 GHz and 3 GHz.  
   
   
       42 . The device according to  claim 41 , wherein the frequency of the microwave radiation is approximately 2455 MHz.  
   
   
       43 . The device according to  claim 35 , wherein the wavelength and intensity of the microwave radiation of the microwave source are furthermore chosen such that no or virtually no electrostatic charging or spark-overs occur on electrically conductive structure elements on the transparent substrate.  
   
   
       44 . The device according to  claim 43 , wherein the microwave source is pulsed.  
   
   
       45 . The device according to  claim 35 , wherein the wavelength and intensity of the microwave radiation is furthermore chosen such that water at least partly absorbs the microwave radiation.  
   
   
       46 . The device according to  claim 35 , wherein the photomask comprises a frame, the protective film of the photomask is fixed to the frame by means of an adhesive, and the wavelength and intensity of the microwave radiation is furthermore chosen such that the microwave radiation does not damage the adhesive.  
   
   
       47 . The device according to  claim 35 , wherein the microwave source comprises a filter comprising the material of the protective film.  
   
   
       48 . A device for storage and use of at least one photomask for lithographic projection, the device comprising: 
 a container suitable for receiving a photomask, the container comprising a container housing and a closable opening device situated at the container housing and serving for the entry and issuing of the photomask, the container comprising at least one gas inlet opening arranged in such a way that, in the case of purging the photomask, a purge gas flushes around the photomask with a substantially laminar flow; and    an infrared source suitable for emitting infrared radiation comprising a specific wavelength and intensity from the side of the structure elements onto the photomask.    
   
   
       49 . The device according to  claim 48 , wherein the wavelength and/or intensity of the infrared radiation of the infrared source is suitable for heating impurities on the surface of the transparent substrate, in the volume between the surface of the transparent substrate and the protective film or on the surface of the protective film.  
   
   
       50 . The device according to  claim 48 , wherein the wavelength of the infrared radiation of the infrared source is furthermore chosen such that it lies within a range in which the protective film is at least partly transparent to infrared radiation.  
   
   
       51 . The device according to  claim 48 , wherein the wavenumber of the infrared radiation lies within the range of between 1000 cm −1  and 4000 cm −1 .  
   
   
       52 . The device according to  claim 51 , wherein the wavenumber of the infrared radiation lies within the range of between 1100 cm −1  and 1400 cm −1 .  
   
   
       53 . The device according to  claim 51 , wherein the wavenumber of the infrared radiation lies within the range of between 2500 cm −1  and 3500 cm −1 .  
   
   
       54 . The device according to  claim 48 , wherein the intensity of the infrared radiation is chosen such that the infrared radiation heats ammonium sulfate.  
   
   
       55 . The device according to  claim 48 , further comprising a mirror that directs the infrared radiation of the infrared source onto the photomask.  
   
   
       56 . A device for storage and use of at least one photomask for lithographic projection, the device comprising: 
 a container suitable for receiving a photomask, the container comprising a container housing and a closable opening device situated at the container housing and serving for the entry and issuing of the photomask, the container comprising at least one gas inlet opening arranged in such a way that, in the case of purging the photomask, a purge gas flushes around the photomask through a gas feed line; and    a gasket being arranged between said one gas inlet opening and said gas feed line, said gasket providing a collapsible seal between said gas inlet opening and said gas feed line.    
   
   
       57 . The device according to  claim 56 , wherein said container further comprises at least one gas outlet opening arranged in such a way that, in the case of purging the photomask, the purge gas is removed through a gas discharge line and a further gasket being arranged between said one gas outlet opening and said gas discharge line, said further gasket providing a collapsible seal between said gas outlet opening and said gas discharge line.  
   
   
       58 . The device according to  claim 57 , wherein the gasket and/or the further gasket are formed from a self-inflating material.  
   
   
       59 . The device according to  claim 58 , wherein the gasket is arranged in a toroidal shape between the gas inlet opening  40  and the gas feed line.  
   
   
       60 . The device according to  claim 58 , wherein the gasket is provided as a collapsible gasket having a passive state of being collapsed.  
   
   
       61 . The device according to  claim 58 , wherein the gasket is provided as a collapsible gasket having a passive state of being expanded.  
   
   
       62 . The device according to  claim 57 , wherein the gas inlet opening is arranged as a stub and the gas feed line is adapted to house the gas inlet opening in an overlapping manner.  
   
   
       63 . The device according to  claim 62 , wherein the gas discharge line is arranged as a stub and the gas outlet opening is adapted to house the gas discharge line in an overlapping manner.  
   
   
       64 . The device according to  claim 62 , wherein the gasket and/or the further gasket are arranged as a sleeve having a double-walled cross-section.  
   
   
       65 . The device according to  claim 64 , wherein the sleeve comprises an outer wall member and an inner wall member which are arranged such that a passing gas stream unfolds the inner wall member and the out wall member to provide the collapsible seal.  
   
   
       66 . The device according to  claim 65 , wherein said outer wall member or said inner wall member comprise an elastic material.  
   
   
       67 . The device according to  claim 66 , wherein said outer wall member and said inner wall member being subdivided into a plurality of fins which partially overlap each other.  
   
   
       68 . The device according to  claim 67 , wherein said fins are arranged such that the purge gas bends the fins in order to provide the collapsible seal.  
   
   
       69 . A device for storage and use of a work piece in semiconductor manufacturing, the device comprising: 
 a container suitable for receiving the work piece, the container comprising a container housing and a closable opening device situated at the container housing and serving for the entry and issuing of the work piece, the container comprising at least one gas inlet opening arranged in such a way that, in the case of purging the work piece, a purge gas flushes around the work piece through a gas feed line; and    a gasket being arranged between said one gas inlet opening and said gas feed line, said gasket providing a collapsible seal between said gas inlet opening and said gas feed line.    
   
   
       70 . The device according to  claim 69 , wherein said work piece comprises a plurality of semiconductor wafers.  
   
   
       71 . The device according to  claim 69 , wherein said work piece comprises a photo mask.  
   
   
       72 . A method for using a device in a fabrication installation, the method comprising: 
 providing a fabrication installation comprising at least one exposure apparatus suitable for receiving the photomask;    feeding the photomask from the container into the exposure apparatus;    carrying out one or more exposure processes with the exposure apparatus using light from a UV source;    removing the photomask from the exposure apparatus into the container; and    cleaning the photomask in the container by purging with the purge gas.    
   
   
       73 . The method according to  claim 72 , further comprising: 
 providing the microwave source;    irradiating the photomask with microwave radiation; and    cleaning the photomask in the container by purging with the purge gas.    
   
   
       74 . The method according to  claim 72 , further comprising: 
 providing the infrared source;    irradiating the photomask with microwave radiation; and    cleaning the photomask in the container by purging with the purge gas.