Method and apparatus for enhancing endpoint detection of a via etch

A method used in processing a semiconductor wafer, comprising:

• forming a first process layer;
• forming a second process layer above said first process layer;
• forming a first masking layer above at least a portion of said second process layer, leaving an outer edge portion of at least said second process layer exposed;
• performing an etching process to remove said outer edge portion of said first and second layers;
• removing said first masking layer;
• forming a second masking layer above said second process layer;
• patterning said second masking layer to expose portions of said first process layer;
• and
• performing an etching process to substantially remove said exposed portions of said first process layer.

A method used in processing a semiconductor wafer, comprising:

• forming a first process layer above the wafer;
• forming a first masking layer above at least a portion of said first process layer, said first masking layer having an outer edge;
• and
• performing at least one etching process to remove said first process layer extending beyond said outer edge of said first masking layer;
• forming a second process layer above said first process layer;
• forming a second masking layer above said second process layer;
• patterning said second masking layer to expose portions of said first process layer;
• and
• performing at least one etching process to remove said exposed portions of said second process layer.

A method used in processing a semiconductor wafer, comprising:

• forming a first process layer above the wafer;
• forming a first masking layer above at least a portion of said first process layer, said first masking layer having an outer edge;
• and
• performing at least one etching process to remove said first process layer extending beyond said outer edge of said first masking layer;
• forming a second process layer above said first process layer;
• forming a second masking layer above said second process layer, said second masking layer having an outer edge;
• performing at least one etching process to remove said second process layer extending beyond said outer edge of said second masking layer.

A method used in processing a semiconductor wafer, comprising:

• forming a first process layer above the wafer;
• forming a first masking layer above at least a portion of said first process layer, the first masking layer being without openings;
• patterning the first masking layer to form a solid layer having a first outer edge;
• performing at least one etching process to remove the first process layer extending beyond the first outer edge of the solid layer;
• forming a second process layer above the first process layer;
• forming a second masking layer above the second process layer;
• patterning said second masking layer to expose portions of the second process layer;
• and
• performing at least one etching process to remove the exposed portions of the second process layer.

A method used in processing a semiconductor wafer, comprising:

• forming a first process layer above the wafer;
• forming a second process layer above the first process layer, leaving an outer edge portion of at least the first process layer exposed;
• forming a first masking layer above at least a portion of the second process layer;
• and
• performing an etching process to remove at least the outer edge portion of the first process layer.