Atomic Layer Etching Applications in Nano-Semiconductor Device Fabrication

These days, the process of plasma etching is exhibited in various forms, including the reactive ion etching (RIE) method. Not only memory device but also computing element such as system semiconductor is becoming more important, and more in demand than ever. In tandem with that demand increase trend, semiconductor process should be sophisticated to manufacture extremely complex semiconductor device structure. However, the downscaling of semiconductor devices has given rise to certain limitations, such as etch profile, short channel effect (SCE), control of critical dimension and material selection. Therefore, to overcome these complex problems, atomic layer etching (ALE) technology was developed, which is more precise compared to the existing method by using repetitive process between modification (self-limiting) and removal. This study analyzes the overall trend of the ALE technology currently being investigated in the field of semiconductors. In particular, we describe the application of ALE to Si, Ge, W, GaN, SiO2 layers, and graphene layers. Also the process of overcoming the above-mentioned limitations using ALE in semiconductor manufacturing processes. The ALE technology is considered as one of the leading new paradigms in the manufacture of semiconductor devices, such as improving 3D nanostructure device structure, High-K oxide etching, line edge/width roughness (LER/LWR), and the selective Atomic Layer Deposition (ALD) in the future. Atomic Layer Deposition (ALD) is a thin-film deposition process, one of chemical vapor deposition based on the sequential use of a gas-phase materials. Although there are limitations to be challenged, ALE technology will be as one of counterplan of conventional etching technology in post-semiconductor industry.