Wafer 415-T
Wafer 415-T has been delivered to the lab. It was processed with TEOS and annealed at 950 C. There are a few usable samples, especially along the edge of the wafer. Pinhole density increases as you move towards the center. The uniformity across the wafer is good.
From left to right, top to bottom: (0,1) @ 35kx; (0,1) @ 35kx; (-5,0) @ 35kx; (-5,0) @ 50kx
I purposely skipped the hot H20 rinse after EDP etching to see what the edge would look like. You can see darker spots along the edges which could be precipitates from the etch.
These edges look much cleaner to me as the intermediate band is gone. Is the only difference that you skipped the hot water rinse? Or were some other solutions changed out as well? We should do a well-organized study of this characteristic, as I doubt these images can really be directly compared to the previous ones (etch time, wafer position, processing variables, etc. likely different). Is the H2SO4 clean still being done?