Scanned focus deposition system

Abstract

There is provided a deposition system ( 1 ) for yielding substantially uniform deposition of an evaporant material onto a substrate. The deposition system ( 1 ) comprises: a source ( 10 ) for generating a coherent energy beam; a substantially planar target ( 60 ) containing the evaporant material and disposed in spaced relation to the substrate; a focusing element ( 30 ) optically coupled to the source for focusing the coherent energy beam onto the target ( 60 ); and, an actuator ( 40 ) coupled to the focusing element ( 30 ) for reversibly translating the focusing element ( 30 ) along a scanning path directed substantially parallel to a target plane defined by the target ( 60 ). The focused coherent energy beam defines an impingement spot ( 14 ) on the target ( 60 ). The impingement spot ( 14 ) is displaced responsive to the translation of the focusing element ( 30 ) along the scanning path. The focus of the coherent energy beam on the target ( 60 ) thus remains substantially preserved.

What is claimed is:  
     
         1 . A deposition system for substantially uniform deposition of an evaporant material onto a substrate comprising: 
 (a) a source for generating a coherent energy beam;    (b) a substantially planar target disposed in spaced relation to the substrate and defining a target plane, said target containing the evaporant material;    (c) a focusing element optically coupled to said source for focusing said coherent energy beam onto said target, said focused coherent energy beam defining an impingement spot on said target; and,    (d) an actuator coupled to said focusing element for reversibly translating said focusing element along a scanning path directed substantially parallel to said target plane for displacing said impingement spot;    whereby said focus of said coherent energy beam on said target remains substantially preserved.    
     
     
         2 . The deposition system as recited in  claim 1  wherein said target is rotated about a target rotation axis substantially normal to said target plane.  
     
     
         3 . The deposition system as recited in  claim 2  wherein said actuator is adapted to automatically translate said focusing element in reciprocal manner.  
     
     
         4 . The deposition system as recited in  claim 3  wherein said actuator is adapted to translate said focusing element in accordance with a predetermined rate profile based upon the position of said impingement spot relative to said target rotation axis.  
     
     
         5 . The deposition system as recited in  claim 4  wherein said predetermined rate profile is defined by a substantially sinusoidal displacement profile, the rate of said translation being inversely related to the displacement of said impingement spot from said target rotation axis.  
     
     
         6 . The deposition system as recited in  claim 1  wherein said focusing element includes a convex lens.  
     
     
         7 . The deposition system as recited in  claim 1  wherein said scanning path is described by a plurality of directional components, each said directional component being substantially parallel to said target plane.  
     
     
         8 . The deposition system as recited in  claim 7  further comprising a vertical actuator coupled to said focusing element.  
     
     
         9 . The deposition system as recited in  claim 4  wherein said actuator includes an angularly displaceable platform member having a sidewall portion defining therefor a predetermined peripheral contour.  
     
     
         10 . The deposition system as recited in  claim 4  wherein said actuator includes: 
 (a) an angularly displaceable platform member; and,  
 (b) an adjustment member coupled to said platform member in selectively displaceable manner.  
 
     
     
         11 . A reciprocated focusing system for pulsed laser deposition of a target evaporant material onto a substrate comprising: 
 (a) a source for generating a laser beam;    (b) a substantially planar target disposed in spaced relation to the substrate and defining a target plane, said target containing the evaporant material;    (c) a focusing element optically coupled to said source for focusing said laser beam onto said target, said focused laser beam defining an impingement spot on said target; and,    (d) an actuator coupled to said focusing element for reciprocally translating said focusing element along a scanning path to displace said impingement spot, said scanning path being described by at least one directional component, each said directional component of said scanning path being substantially parallel to said target plane;    whereby said focus of said laser beam on said target remains substantially preserved during said displacement of said impingement spot along said target.    
     
     
         12 . The reciprocated focusing system as recited in  claim 11  wherein said target is rotated about a target rotation axis substantially normal to said target plane.  
     
     
         13 . The reciprocated focusing system as recited in  claim 12  wherein said actuator is adapted to translate said focusing element in accordance with a predetermined rate profile based upon the position of said impingement spot relative to said target rotation axis.  
     
     
         14 . The reciprocated focusing system as recited in  claim 13  wherein said predetermined rate profile is defined by a substantially sinusoidal displacement profile, the rate of said translation being inversely related to the displacement of said impingement spot from said target rotation axis.  
     
     
         15 . The reciprocated focusing system as recited in  claim 11  wherein said scanning path is described by a plurality of said directional components.  
     
     
         16 . The reciprocated focusing system as recited in  claim 15  wherein said actuator includes at least first and second actuator components for respectively translating said impingement spot along said directional compnents.  
     
     
         17 . The reciprocated focusing system as recited in  claim 16  wherein at least one of said first and second actuator components is programmable.  
     
     
         18 . A pulsed laser deposition system for substantially uniform deposition of an evaporant material onto a substrate comprising: 
 (a) a source for generating a laser beam;    (b) a substantially planar target disposed in spaced relation to the substrate and defining a target plane, said target containing the evaporant material;    (c) a focusing element optically coupled to said source for focusing said laser beam onto said target, said focused laser beam defining on said target an impingement spot having a predetermined shape and a predetermined size dimension; and,    (d) an actuator coupled to said focusing element for reversibly translating said focusing element along a scanning path described by at least one directional component parallel to said target plane;    whereby said impingement spot is scanned along said target, said predetermined shape and size dimension of said impingement spot on said target being substantially preserved during said scanning.    
     
     
         19 . The pulsed laser deposition system as recited in  claim 18  wherein said target is rotated about a target rotation axis substantially normal to said target plane.  
     
     
         20 . The pulsed laser deposition system as recited in  claim 19  wherein said actuator is adapted to automatically translate said focusing element in reciprocol manner.  
     
     
         21 . The pulsed laser deposition system as recited in  claim 20  wherein said actuator is adapted to translate said focusing element in accordance with a predetermined rate profile based upon the position of said impingement spot relative to said target rotation axis.  
     
     
         22 . The pulsed laser deposition system as recited in  claim 21  wherein the rate of said translation is inversely related to the displacement of said impingement spot from said target rotation axis.  
     
     
         23 . The pulsed laser deposition system as recited in  claim 22  wherein said scanning path is compositely described by a plurality of said directional components.