Analysis of the erbium silicide growth mechanism on SOI for n-type SB-MOSFETs

다국어 초록 (Multilingual Abstract)

We have investigated the formation conditions of the stable Er silicides according to the annealing temperature and various ratios of Er to Si thickness considering the strip process of unreacted Er on the silicon on insulator (SOI) substrate. As the thickness ratio of Er to Si layer increases, the synthesized Er silicides on SOI substrate become gradually unstable. Especially, the Er-rich region is formed near the interface between the Si and BOX layer on decreasing the Si thickness and these unstable Er silicides are easily removed in the strip process by SPM. Also, the amount of Si consumed by Er during the silicide formation and the total thickness of the Er silicides are calculated from the density of the Si, Er, and Er silicide. From the experimental and theoretical results, the thickness of the Er layer should be about 1.5 times greater than the theoretical thickness and must be below 1.5 times the Si thickness to form stable Er silicide.