Low energy deuteriurn ion beam with high beam density was used to bombard deuterated metal target. In order to study the D-D reaction in solid

the relation of D-D reaction in solid and the material structure was studied by analyzing the charged particle spectra of D-D fusion. At the same time

the deuterium cluster-ion beam and deuteron beam were applied to identify the features of D-D fusion beyond the triplantation range of ions. An unknown peak

which appeared between the proton peak (3MeV) and triton peak (1MeV)

was observed. It is identified to be proton peak of the D-D fusion

which occurred far beyond the ion beam implanting range in solid. The isolated deuteron gave higher fusion reaction yield

comparing with the deuteron in cluster-ion with the same velocity. Some interpretations about the experimental phenomena were discussed

based on the basic principles of beam-solid interaction and channeling effect.