| 초록 |
Silicon nitride (SiNx) is widely studied for gate dielectric, charge trap layer and spacer applications in front-end-of-line (FEOL) semiconductor processing. The Most role of SiNx is gate spacer. This SiNx spacer acts as dopant out diffusion barrier and preventing etching damage during later processing. As the device feature size continues to shrink, the allowed thermal budget during processing is decreasing and film quality such as excellent step coverage is required of necessity. Atomic layer deposition (ALD) is an ideal solution to satisfy these requirements due to its self-limited reaction. Moreover, the introduction of plasma can achieve lowering deposition temperature by supplying additional energy from the plasma. However, the ion – substrate bombardment causes damage to the substrate, therefore, Remote plasma ALD (RPALD) has been developed. In this presentation, we discuss silicon nitride deposited by Remote plasma ALD. Furthermore, to gain better quality film, We use 3step recipe introducing intermediate H2 plasma step between the CSN-2 and the N2 plasma step. And we compared two deposition conditions at 350 ℃ due to low thermal budget spacer The silicon nitride (SiNx) was deposited using 1,3-di-isopropylamino-2,4-dimethylcyclosilazane (CSN-2) and N2 remote plasma and H2 remote plasma. Process window, physical and chemical properties of the film were evaluated spectroscopy ellipsometry (SE), auger electron spectroscopy (AES), and x-ray photoelectron spectroscopy (XPS). And to compare two different step recipes, transmission electron microscopy (TEM) and wet etch rate test (WER) was carried out. |
