Precision screen printing with sub-micron uniformity of metallization materials on green sheet ceramic

Abstract

Precision screen printing is described that is capable of sub-micron uniformity of the metallization materials that are printed on green sheet ceramic. In some examples, puck is formed with electrical traces by screen printing a paste that contains metal on a ceramic green sheet in a pattern of electrical traces and processing the printed green sheet to form a puck of a workpiece carrier. In some example, the printing includes applying a squeegee of a screen printer to the printed green sheet in a squeegeeing direction while the green sheet is on a printer bed of the screen printer. The method further includes mapping the printer bed at multiple locations along the squeegeeing direction, identifying non-uniformities in the printer bed mapping, and modifying a printer controller of the screen printer to compensate for mapped non-uniformities in the printer bed.

What is claimed is: 
     
         1 . A top plate of a workpiece carrier, comprising:
 a plurality of ceramic green sheets; and   a printed ceramic green sheet having conductive patterns printed thereon, the printed sheet being embedded within the plurality of ceramic green sheets, wherein the plurality of ceramic green sheets are sintered and hardened.   
     
     
         2 . The top plate of  claim 1 , wherein the conductive patterns form resistive heaters. 
     
     
         3 . The top plate of  claim 1 , wherein the printed sheet further comprises electrical components attached to the sheet and coupled to the patterns. 
     
     
         4 . The top plate of  claim 3 , wherein the conductive patterns form a coil. 
     
     
         5 . The top plate of  claim 1 , further comprising a frame to carry the hardened plurality of green sheets. 
     
     
         6 . The top plate of  claim 1 , wherein the ceramic green sheets are formed of ceramic powder and glass compacted with a binder. 
     
     
         7 . The top plate of  claim 1 , wherein the printed conductive patterns comprise a conductive metal in a paste form including a suspension and a dispersant dispensed into patterns. 
     
     
         8 . The top plate of  claim 1 , wherein the conductive patterns comprise a plurality of heater traces, each heater trace having a resistivity of at least 50Ω. 
     
     
         9 . The top plate of  claim 1 , wherein printed ceramic green sheet comprises Al 2 O 3 . 
     
     
         10 . The top plate of  claim 1 , wherein printed ceramic green sheet comprises AlN. 
     
     
         11 . The top plate of  claim 1 , wherein the conductive patterns comprise a conductive material selected from the group consisting of tungsten, molybdenum, zinc, silver and gold. 
     
     
         12 . The top plate of  claim 1 , further comprising:
 an upper circular platform above a lower concentric circular base, the lower concentric circular base having a diameter greater than a diameter of the upper circular platform.   
     
     
         13 . The top plate of  claim 12 , wherein the upper platform has internal electrodes to electrostatically attach a workpiece to the top plate. 
     
     
         14 . The top plate of  claim 1 , further comprising:
 internal electrodes to electrostatically attach a workpiece to the top plate.   
     
     
         15 . An electrostatic chuck, comprising:
 a top plate, comprising:
 a plurality of ceramic green sheets; and 
 a printed ceramic green sheet having conductive patterns printed thereon, the printed sheet being embedded within the plurality of ceramic green sheets, wherein the plurality of ceramic green sheets are sintered and hardened; 
   a cooling plate beneath the top plate; and   an adhesive attaching the top plate to the cooling plate.   
     
     
         16 . The electrostatic chuck of  claim 15 , further comprising:
 a base plate beneath the cooling plate.   
     
     
         17 . The electrostatic chuck of  claim 16 , further comprising:
 an insulating plate between the cooling plate and the base plate.   
     
     
         18 . The electrostatic chuck of  claim 15 , wherein the top plate further comprises:
 an upper circular platform above a lower concentric circular base, the lower concentric circular base having a diameter greater than a diameter of the upper circular platform.   
     
     
         19 . The electrostatic chuck of  claim 15 , further comprising:
 internal electrodes to electrostatically attach a workpiece to the top plate.   
     
     
         20 . A plasma system, comprising:
 a processing chamber body having sidewalls and a bottom wall defining a processing region;   an electrostatic chuck in the processing region, the electrostatic chuck comprising:
 a top plate, comprising:
 a plurality of ceramic green sheets; and 
 a printed ceramic green sheet having conductive patterns printed thereon, the printed sheet being embedded within the plurality of ceramic green sheets, wherein the plurality of ceramic green sheets are sintered and hardened; and 
 
 a cooling plate beneath the top plate; and 
 an adhesive attaching the top plate to the cooling plate; 
   a lid coupled to a top portion of the chamber body; and   a showerhead between the lid and the processing region.