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Title: Pulsed laser induced atomic layer etching of silicon
We demonstrate the laser mediated atomic layer etching (ALEt) of silicon. Using a nanosecond pulsed 266 nm laser focused loosely over and in a parallel configuration to the surface of the silicon, we dissociate Cl2 gas to induce chlorination. Then, we use pulsed picosecond irradiation to remove the chlorinated layer. Subsequently, we perform continuous wave (CW) laser annealing to eliminate amorphization caused by the picosecond laser etching. Based on atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS), we observed strong evidence of chlorination and digital etching at 0.85 nm etching per cycle with good uniformity.  more » « less
Award ID(s):
2024391
NSF-PAR ID:
10453049
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of Vacuum Science & Technology A
Volume:
41
Issue:
2
ISSN:
0734-2101
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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