@article{oai:kanagawa-u.repo.nii.ac.jp:00013571,
 author = {中田, 穣治 and 稲垣, 俊哉 and 関, 裕平 and 星野, 靖},
 journal = {Science Journal of Kanagawa University},
 month = {Oct},
 note = {We measured sheet resistances of IIa-type diamond substrates implanted with P ions at a 900℃ substrate temperature and room temperature (RT). Also, O ions were implanted at RT only. P and O elements have been considered possible donor candidates in diamond substrates. However, there has been no report on successfully achieving n -type conductivity using ion implantation methods in reproducible and reliable ways. Electrical measurements were performed just after implantation and after subsequent annealing at 1150℃ and 1300℃. Concerning P-implanted samples at 900℃ , we recorded activation energy of 0.6 eV for samples after implantation and after 1150℃ post-annealing with flat and average concentrations of 5.0×1019/ cm3 and 5.0×1020/cm3. This 0.6 eV value was obtained within a 300~600℃ temperature range and corresponded to marked P activation energy. Concerning O-implanted samples at RT, sheet resistances show higher values with increasing but not decreasing temperatures. This hysteresis phenomenon also appeared in RT P-implantation cases. It can be concluded that in both P and O RT-implanted cases, defects introduced during implantation would be annealed during sheet resistance measurements in the increasing temperature stage. It is suggested that 900℃ implantation is favorable for RT implantation, in the sense of achieving activation energy of 0.6 eV , which is thought to be the ionization energy of P-implanted samples. However, in almost all samples measured in the present experiments, we cannot judge n -type conduction by Hall Effect measurements. This fact strongly suggests that hopping conduction occurred in the subband formed in the wide band gap in the diamond substrate. It is suggested that this sub-band is formed by secondary defects consisting of stacking faults or dislocations resulting from primary defects of vacancies and interstitials introduced by RT ion implantation. It is proposed that the IBIEC (Ion-Beam-Induced Epitaxial Crystallization) method is favorable to any other annealing method such as furnace annealing, rapid thermal annealing, and electron or laser beam annealing, in order to reduce secondary defects that might cause the formation of a conductive sub-band in the wide-band gap of the diamond substrates. This is because IBIEC is a low-temperature annealing method involving a non-equilibrium process. Low temperature decreases the formation of secondary defects, resulting in reducing the formation of conductive sub-bands. Eventually, hopping conduction would not occur, and p -type or n -type conduction might be expected . It is concluded that fundamental and basic research is needed on the mechanism of defect formation during ion implantation into diamond substrates, and on the mechanism of secondary defects during electrical measurement and annealing., Departmental Bulletin Paper, 原著, 2019年度神奈川大学総合理学研究所共同研究助成論文},
 pages = {41--51},
 title = {IIa型CVDダイヤモンド基板にｎ型ドーパント元素をイオン注入しポストアニールによって形成した電気伝導層の電気特性},
 volume = {31},
 year = {2020}
}