Plasma deposition on a partially fabricated battery cell through a mesh screen

Abstract

A plasma chamber for depositing a battery component material on a partially fabricated battery cell comprising a battery component layer containing charge-carrying metal species and having an exposed surface. The chamber comprises a support carrier to hold a battery support comprising the partially fabricated battery cell. A mesh screen is positioned at a preset distance from the support carrier, the mesh screen having a plurality of mesh openings. An exhaust maintains a pressure of the process gas in the plasma chamber. A plasma power source is capable of applying an electrical power to the process gas to generate a plasma from the process gas for plasma deposition, during which the mesh screen is capable of reducing migration of the charge-carrying metal species across the battery component layer.

What is claimed is: 
     
         1 . A plasma chamber for depositing a battery component layer on a partially fabricated battery cell comprising a battery component layer containing charge-carrying metal species and an exposed surface, the chamber comprising:
 (a) a support carrier to hold a battery support comprising the partially fabricated battery cell;   (b) a mesh screen spaced apart, and positioned at a preset distance, from the support carrier, the mesh screen having a plurality of mesh openings;   (c) a gas distributor to introduce a process gas into the plasma chamber;   (d) an exhaust to maintain a pressure of the process gas in the plasma chamber; and   (e) a plasma power source capable of applying an electrical power to the process gas to generate a plasma from the process gas,   whereby during plasma deposition, the mesh screen is capable of reducing migration of the charge-carrying metal species across the battery component layer.   
     
     
         2 . A chamber according to  claim 1  comprising at least one of:
 (i) a mesh screen power source that maintains the mesh screen at a positive or negative bias; 
 (ii) the mesh screen is maintained at electrical ground; or 
 (iii) the mesh screen is maintained at a floating potential. 
 
     
     
         3 . A chamber according to  claim 1  wherein the mesh screen comprises (i) a wire grid, or (ii) a solid sheet with the mesh openings. 
     
     
         4 . A chamber according to  claim 1  wherein the mesh screen comprises mesh openings comprising at least one of the following:
 (i) a cumulative open area which is at least 70% of the total area of the mesh screen; 
 (ii) an open area of at least 0.25 mm 2 ; and 
 (iii) a dimension of at least 0.5 mm. 
 
     
     
         5 . A chamber according to  claim 1  wherein the mesh screen is positioned at a preset distance that is at least one of:
 (i) at least 0.5 cm; or 
 (ii) less than 20 cm. 
 
     
     
         6 . A chamber according to  claim 1  adapted to be a sputtering chamber having a sputtering target that is electrically coupled to the plasma power source to generate a sputtering plasma to sputter battery component material from the sputtering target. 
     
     
         7 . A chamber according to  claim 1  adapted to be a plasma-enhanced evaporative chamber having an evaporation source holding the battery component material and an evaporator for evaporating the battery component material from the evaporation source. 
     
     
         8 . A chamber according to  claim 1  adapted to be a plasma-enhanced CVD chamber having process electrodes for generating a plasma upon application of the electrical power to the process electrodes. 
     
     
         9 . A chamber according to  claim 1  wherein the partially fabricated battery cell comprises a battery component layer that is at least one of:
 (i) a cathode or electrolyte; and 
 (ii) a lithium-containing material. 
 
     
     
         10 . A chamber according to  claim 9  wherein the lithium-containing material comprises lithium cobalt oxide or LiPON. 
     
     
         11 . A chamber according to  claim 1  adapted to deposit a battery component material comprising lithium, lithium oxide, LiPON or copper. 
     
     
         12 . A sputtering chamber for depositing a battery component layer on a partially fabricated battery cell comprising a battery component layer containing charge-carrying metal species and an exposed surface, the chamber comprising:
 (a) a sputtering target comprising a sputtering member composed of the battery component material;   (b) a support carrier facing the sputtering target, the support carrier being adapted to hold a battery support comprising the partially fabricated battery cell;   (c) a mesh screen spaced apart, and at a preset distance, from the support carrier, the mesh openings having a plurality of mesh openings;   (d) a gas distributor to introduce a process gas into the sputtering chamber;   (e) an exhaust to maintain a pressure of the process gas in the sputtering chamber; and   (f) a plasma power source to apply an electrical power to the sputtering target to form a sputtering plasma to sputter the battery component material off the sputtering target and onto the battery component layer of the partially fabricated battery cell.   
     
     
         13 . A chamber according to  claim 12  wherein the mesh screen is electrically charged, grounded or floating. 
     
     
         14 . A chamber according to  claim 12  comprising a magnetron abutting the sputtering target. 
     
     
         15 . A chamber according to  claim 12  wherein the sputtering target is composed of at least one of lithium, lithium oxide, LiPON or copper. 
     
     
         16 . A plasma evaporation chamber for depositing a battery component layer on a partially fabricated battery cell comprising a battery component layer containing charge-carrying metal species and an exposed surface, the chamber comprising:
 (a) an evaporation source comprising a crucible containing a metal-containing source material composed of the battery component material;   (b) a support carrier facing the evaporation source, the support carrier adapted to hold a battery support comprising the partially fabricated battery cell;   (c) a mesh screen spaced apart, and positioned at a preset distance, from the support carrier, the mesh screen having a plurality of mesh openings;   (d) a gas distributor to introduce an inert gas into the sputtering chamber;   (e) an exhaust to maintain a pressure of the inert gas in the sputtering chamber; and   (f) a plasma power source to apply an electrical power to a coil to form a plasma.   
     
     
         17 . A chamber according to  claim 16  wherein the mesh screen is positioned at a preset distance of at least 1 cm and less than 20 cm from the support carrier. 
     
     
         18 . A chamber according to  claim 16  wherein the mesh screen comprises mesh openings comprising at least one of the following:
 (i) a cumulative open area which is at least 70% of the total area of the mesh screen; 
 (ii) an open area of at least 0.25 mm 2 ; and 
 (iii) a dimension of at least 0.5 mm. 
 
     
     
         19 . A chamber according to  claim 16  wherein the metal-containing source material is composed of at least one of lithium, lithium oxide, LiPON or copper. 
     
     
         20 . A chamber according to  claim 16  wherein the partially fabricated battery cell comprises a battery component layer that is at least one of:
 (i) a cathode or electrolyte; and 
 (ii) a lithium-containing material.