(2) Improvement of surface tribology by ion beam bombardment.
　Effects of ion beam bombardment on surface tribology are studied by a tibometer, nano-scale tribology measurements using AFM, a Vickers hardness tester, a micro hardness tester by an indentation method. These results are compared with the depth profiles of elemental composition measured by RBS, ERD, and AES, with the chemical structure measured by XPS, and with the crystalline structure by glancing angle XRD.

(3) Computer simulation of ion-solid interaction
　Dynamic-SASAMAL, a dynamic Monte Carlo simulation code, was developed. Using the code, the fluence dependence of depth profile of composition and vacancy under high fluence implantation of ions of keV to MeV order are calculated and compared with experimental results.

(2) Oxygen depth profiling by resonant backscattering with He ions.
　Presize depth profiling was realized by controlling the analyzing ion energy by the bias voltage induced on the sample holder without changing the accelerator voltage.

(3) Depth profiling of nitrogen by the resonant nuclear reaction analysis using 15N12C reaction.
　Nitrogen behavior at every stage of the implantation is studied using alternative implantation of 15N and 15N.

(4) Hydrogen depth profiling by ERD and NRA.

(5) Analysis of neighboring atoms by heavy ion RBS.