Amorphization and recrystallization of 6H-SiC by ion-beam irradiation

Abstract

Amorphization of 6H-SiC with 200 keV Ge+ ions at room temperature and subsequent ion-beam-induced epitaxial crystallization (IBIEC) with 300 keV Si+ ions at 480 °C have been studied by Rutherford backscattering spectrometry/channeling and transmission electron microscopy analysis. Experimental results on amorphous layer thicknesses have been compared with trim calculations in association with the critical energy density model. Density changes during amorphization have been observed by step height measurements. Particular attention has been directed to the crystal quality and a possible polytype transformation during the IBIEC regrowth. The IBIEC process consists of two stages and results in a multilayer structure. In the initial phase an epitaxial growth of 6H-SiC has been obtained. With increasing IBIEC dose the epitaxial growth changes to columnar growth and is stopped by polycrystallization of 3C polytype in the near-surface region.

Ion-beam synthesis of amorphous SiC films: Structural analysis and recrystallization

“…[5][6][7] To avoid this problem, the use of ion-beam induced epitaxial crystallization ͑IBIEC͒ has been recently studied. 8 Heera et al have reported the recrystallization of 6H-SiC wafers amorphized by Ge ϩ ion implantation by the use of Si ϩ ion implantation at temperatures as low as 480°C. 8 However, in this work recrystallization is not complete, being the regrowth process stopped by polynucleation near the surface region.…”

“…8 Heera et al have reported the recrystallization of 6H-SiC wafers amorphized by Ge ϩ ion implantation by the use of Si ϩ ion implantation at temperatures as low as 480°C. 8 However, in this work recrystallization is not complete, being the regrowth process stopped by polynucleation near the surface region. To clarify the mechanisms involved, further experiments are needed, including the analysis of amorphous layers obtained by different processes.…”

Infrared reflection investigation of ion‐implanted and post‐implantation‐annealed epitaxially grown 6H‐SiC

“…Thirdly, along with the normal amorphization as a result of atomic displacement, implants may also cause high stress to accumulate in the region behind the distribution of the damage energy. 20 Last, but not the least, excess carbon implantation may enhance the amorphization process, 25 and therefore the amorphous layer can be thicker than the calculations suggested. The thickness of the deepest implantation range, R p C 2R p , 26 of Al (197 keV) is 0.34 µm, which agrees with our fitted result.…”

An EPR study of defects induced in 6H-SiC by ion implantation

“…There is an EPR signal even for the unimplanted wafer. It consists of an isotropic line with zero-crossing g value, go, of 2.0029 + 0.0002, peak-to-peak width, AB , of 0 47 + 0 02 mT and is 9 PP 9 --. slightly asymmetric m shape.…”