Aspects of ions induced texture evolution on Ge surface: A statistical assessment

作者：Garg S K; Datta D P; Kanjilal D; Som T^*

来源：Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms , 2017, 409: 181-186.

DOI：10.1016/j.nimb.2017.04.012

• Ion irradiation
• Nano scale pattern
• Statistical analysis

We study the temporal variation in texture of Ge surface undergoing 100 keV Kr+ ion implantation as a function of ion incidence angle. Our experimental results show that ripple patterns develop on the Ge surface, which gradually transform into faceted structures. In order to understand the compatibility of such surface texture for various applications, we evaluate regularity of patterns in terms of orientation and shape, homogeneity, the effective increment in the surface area, etc. These information are extracted from statistical parameters, namely surface texture area ratio, texture direction index, texture aspect ratio, ratio of system correlation length to ripple wavelength, directional roughness exponents, and anisotropy ratio, computed from atomic force microscopic images of the implanted surfaces. We find that the ripple patterns are most regular in a narrow range of ion incidence angle around theta = 45 degrees. However, at higher angles, regularity in pattern is found to improve at higher ion fluences. Further, higher surface area of irradiated Ge is observed at highest fluences. Indeed, these findings can help to decide the optimized value of ion fluence for creating the desired surface texture required for particular application. Further scaling analysis reveals that the present case can be associated with two universality classes of scaling, namely Family-Vicsek or intrinsic universality class.

• 出版日期2017-10-15