The Early Stages of Etching
In order to develop an understanding of the initial formation of holes, high magnifications were used to study how etching occurs in the first hour.
Note: This particular batch was etched in 70 degree 6M NaOH. This would yield smaller diameter pits than the standard 80 degree etch.
| 20 minutes ( — = 1.63 um) | 25 minutes( — = 1.81 um) | 30 minutes( — = 1.81 um) |
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| 35 minutes( — = 2.65 um) | 40 minutes( — = 1.95 um) | 45 minutes( — = 1.93 um) |
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| 50 minutes( — = 2.55 um) | 55 minutes( — = 2.78 um) | 60 minutes( — = 2.55 um) |
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