Protective shield around the inner edge of endpoint window in a plasma etching chamber

A protective shield around a window in a plasma etcher comprising:

• a plasma etcher having a wall surrounding a chamber, an opening in said wall;
• said wall having an inside face and an outside face;
• said inside face of said wall covered by a protective coating;
• an opening edge, of said wall, defining said opening;
• a window pane over said opening and over a portion of said outside face of said wall;
• the improvement being;
• a shield covering said opening edge of said wall around said opening and a portion of said inside face of said wall around said opening;
• and covering portions of said protective coating adjacent to said opening;
• said shield comprised of an electrically insulating and plasma resistant material;
• said protective shield has a thickness in a range of between 0.5 and 3.0 mm;
• whereby said shield prevents the chamber from arcing and generating particles and extend the lifetime of said well.

A protective shield around a horizontal window in a plasma etcher comprising:

• a plasma etcher having a wall surrounding a chamber, an opening in said wall;
• said wall having an inside face and an outside face;
• said inside face of said wall covered by a protective coating;
• a opening edge, of said wall, defining said opening;
• a window pane over said opening and over a portion of said outside face of said wall;
• said chamber comprised of a material selected from the group consisting of aluminum, stainless-steel and Ti;
• said chamber has a coating of anodized material composed of aluminum oxide and said coating being an electrical insulator;
• a shield covering said opening edge of said wall around said opening and a portion of said inside face of said wall around said opening;
• said shield covers said opening edge around said opening and covers a portion between about 5 and 20 mm of the inside face of the wall 30 around the opening;
• and covering portions of said protective coating adjacent to said opening;
• and covering a portion of said window pane adjacent to said opening;
• said shield comprised of an electrically insulating and plasma resistant material;
• said protective shield is comprised of polytetrafluoroethlyene and has a thickness in a range of between 0.5 and 3.0 mm;
• whereby said shield prevents the chamber from arcing and generating particles and extend the lifetime of said well.