[16p-412-1~20] 13.5 Semiconductor devices and related technologies

△ [16p-412-14] Effect of cooling process on compressive strain in GOI layers fabricated by Ge condensation

〇(D)Wukang Kim¹, Mitsuru Takenaka¹, Shinichi Takagi¹ (1.The Univ. of Tokyo)

Keywords:Ge condensation, GOI, Compressive Strain

Ge has high potential for a next generation channel material because of the high elecrtron and hole mobility and easy introduction into the Si platform. Moreover, a UTB (Ultra-thin body) GOI (Ge-on-Insulator) structure is very important to suppress the short channel effect. Among the several GOI fabrication methods, the Ge condensation method is one of the most promising techiniques to fabricate UTB GOIs. However, one of the problems in Ge condensation is the relaxation of strain during the condensation process, which not only causes defects on GOI layers but also prevents high performance in pMOSFETS. Therefore, it is crucial to suppress the strain relaxation during Ge condensation. We have recently reported that compressive strain remains in GOI layers by reducing temperature cycles with slow cooling process during the Ge condensation. However, the impact of the cooling time on remaining strain has not been examined yet. In this study, we have examined the effect of cooling time in Ge condensation method on strain in GOI. The slower GOI cooling process with the continuous oxidation/ annealing in furnaces resulted in higher compressive strain in GOI layers, which is expected to provide higher hole mobility in pMOSFETs.