Specific Process Knowledge/Etch/ICP Metal Etcher/Chromium/End point: Difference between revisions
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I was looking at trenches with sizes ranging from 200 nm to 2 µm in width. The masking materials was negative DUV resist: NUV 2300-0.5 of approximately 500 nm. The process flow can be seen here: [[:File:Process_flow_for_test_wafers xx.pdf]] | I was looking at trenches with sizes ranging from 200 nm to 2 µm in width. The masking materials was negative DUV resist: NUV 2300-0.5 of approximately 500 nm. The process flow can be seen here: [[:File:Process_flow_for_test_wafers xx.pdf]] | ||
== | ==Etch close to optimal== | ||
The etch rate is faster near the edge. Therefor the trenches are in general wider at the edges. Here all structures has been etched down to the SiO2 layer and the dimensions are close to being unaffected, especially in the middel. The sidewalls are close to 90 degrees; Sometimes a little positive and sometimes a little negative. The improve more the etch rate should be more uniform over the wafer and the Cr should be with small grain sizes. I stopped '''41 s after the end point curve 'SUM_C2' top point on the barc etch''' and '''170 s after the end point curve 'CR_Avg_5208' started to drop on the Cr etch'''. | The etch rate is faster near the edge. Therefor the trenches are in general wider at the edges. Here all structures has been etched down to the SiO2 layer and the dimensions are close to being unaffected, especially in the middel. The sidewalls are close to 90 degrees; Sometimes a little positive and sometimes a little negative. The improve more the etch rate should be more uniform over the wafer and the Cr should be with small grain sizes. I stopped '''41 s after the end point curve 'SUM_C2' top point on the barc etch''' and '''170 s after the end point curve 'CR_Avg_5208' started to drop on the Cr etch'''. | ||