Direct combination of carbon structure with optoelectronics crystal: thermal behavior of implanted carbon in lithium niobate crystal at near surface

Abstract

The thermal motion mechanism of carbon (C) in lithium niobate (LiNbO _3 ) crystal was briefly studied, which provides experience and direction for the experimental parameters of graphene production by direct implantation of carbon ions into LiNbO _3 . Thin-film LiNbO _3 crystal and bulk LiNbO _3 crystal of z-cut were direct implanted by carbon ions with a dose of 1.14 × 10 ^16 cm ^−2 and then annealed at different temperatures, thin-film LiNbO _3 at 700 °C and bulk LiNbO _3 at 900 °C. The experimental conditions and parameters of ion implantation and annealing were all the same except the annealing temperature. The samples were characterized by RBS, XRD, EDS and Raman spectrum. The results show that during annealing, the implanted carbon ions aggregate into clusters while moving towards the surface. This behavior prevents the carbon ions from precipitating on the LiNbO _3 surface, which is not conducive to the production of graphene. The formation of graphene on LiNbO _3 surface by direct ion implantation can only occur when implanted C dose and annealing temperature lie in a specific range.

Keywords

• lithium niobate
• thermal motion
• graphene
• ions implantation
• annealing