Corrosion-resistant gas distribution plate for plasma processing chamber

Abstract

Disclosed herein is a gas distribution plate for use in a gas distribution assembly for a processing chamber, where the gas distribution plate is fabricated from a solid yttrium oxide-comprising substrate, which may also include aluminum oxide. The gas distribution plate includes a plurality of through-holes, which are typically crescent-shaped. Through-holes which have been formed in the solid yttrium oxide-comprising substrate by ultrasonic drilling perform particularly well. The solid yttrium oxide-comprising substrate typically comprises at least 99.9% yttrium oxide, and has a density of at least 4.92 g/cm 3 , a water absorbency of about 0.02% or less, and an average grain size within the range of about 10 μm to about 25 μm. Also disclosed herein are methods for fabricating and cleaning the yttrium oxide-comprising gas distribution plate.

1 . A gas distribution plate for use in a gas distribution assembly in a processing chamber, wherein said gas distribution plate is fabricated from a solid yttrium oxide-comprising substrate, and wherein said gas distribution plate includes a plurality of through-holes. 
   
   
       2 . A gas distribution plate in accordance with  claim 1 , wherein said through-holes have been formed in said solid yttrium oxide-comprising substrate by ultrasonic drilling. 
   
   
       3 . A gas distribution plate in accordance with  claim 2 , wherein said through-holes are crescent-shaped. 
   
   
       4 . A gas distribution plate in accordance with  claim 1 , wherein said solid yttrium oxide-comprising substrate comprises at least 99.9% yttrium oxide. 
   
   
       5 . A gas distribution plate in accordance with  claim 4 , wherein said solid yttrium oxide-comprising substrate has a density of at least 4.92 g/cm 3 . 
   
   
       6 . A gas distribution plate in accordance with  claim 1  or  claim 4  or  claim 5 , wherein said solid yttrium oxide-comprising substrate has a water absorbency of about 0.02% or less. 
   
   
       7 . A gas distribution plate in accordance with  claim 1  or  claim 4  or  claim 5 , wherein said solid ttrium oxide-comprising substrate has an average grain size within the range of about 10 μm to about 25 μm. 
   
   
       8 . A gas distribution plate in accordance with  claim 1 , wherein said solid yttrium oxide-comprising substrate includes impurities at equal to or less than the following maximum concentrations: 90 ppm Al; 10 ppm Ca; 5 ppm Cr; 5 ppm Cu; 10 ppm Fe; 5 ppm K; 5 ppm Mg; 5 ppm Na; 5 ppm Ni; 120 ppm Si; and 5 ppm Ti. 
   
   
       9 . A gas distribution plate in accordance with  claim 1 , wherein at least a portion of a surface of said solid yttrium oxide-comprising substrate is fluorinated. 
   
   
       10 . A gas distribution plate in accordance with  claim 1 , wherein said processing chamber is used for plasma processing. 
   
   
       11 . A gas distribution plate in accordance with  claim 10 , wherein said plasma processing is performed in the presence of halogen-comprising species. 
   
   
       12 . A gas distribution plate in accordance with  claim 11 , wherein said halogen-comprising species include chlorine-comprising species. 
   
   
       13 - 34 . (canceled)