High selective atomic layer etching in combination with area-selective deposition for atomic-scale process design

Abstract We investigated the critical process steps to realize high selective SiO 2 atomic layer etching (ALE) in combination with area-selective deposition (ASD) of a carbon mask. To realize high selective etching, it is important to effectively utilize the difference in incubation time of the carbon deposition on different surfaces. It was found that the incubation time of carbon deposition on SiO 2 can be controlled by adjusting the amount of oxygen from the plasma and substrate. As a result, ultra-high selective etching can be realized by combining ASD with CH 4 /O 2 /Ar plasma for carbon mask deposition and ALE with C 4 F 8 /Ar plasma adsorption, followed by Ar plasma desorption.