Determination of Surface Modified CVD Diamond/ Si(111) Film Post Implanted Ion Fe-B and NiFe-B Related to Magnetoresistance Properties

Nanostructure investigation on the post implantation by Fe-B and NiFe-B on CVD diamond/Si(111) film have been studied by means of STEM related to their Magnetoresistance(MR) phenomena. Two samples were investigated carefully, firstly sample is post NiFe-B at E=70keV and dose= 1015 ions/cm2 (denoted as A-E3D1). Secondly, is post FeB at E=20 keV and dose= 1015 ions/cm2 (denoted as B-E1D1). Based on FPP measurement at room temperature (RT) and Happlied=8 kOe, A-E3D1 sample has MR ratio almost 80% and MR ratio in B-E1D1 sample is 45%. Based on STEM-EDX investigation, there are two aspects of how MR ratio of A-E3D1 more higher than those of B-E1D1. Firstly, surface nanostructure on the top of A- E3D1 film is more grazing than on the top of B-E1D1. Analysis with Scanning Transmission Electron Microscope (STEM) equipped with Electron Energy Loss Spectroscopy (EELS) the growth of amorphous carbon layer on top of the implanted diamond film with thickness around 100 nm and only 20 nm on the no implanted sample have observed. Boron atoms were found inside the carbon amorphous layer distributed homogenously. Secondly, oxygen content at the interface between diamond film and silicon substrate in sample A-E3D1 was lower than those in B-E1D1 sample. This condition gives the resistance value in A-E3D1 lower than value in B-E1D1. This result is close to the Raman Spectroscopy data measurement which obviously suggests changes on the Raman spectrum due to implantation related to Oxygen excitation from B-E1D1 sample and the properties of magnetic film, respectively.