Since Liu and Cohen predicted that the bulk modulus of carbon nitride films with the structure of β-C3N4 are comparable or even surpass those of diamond, intensive experimental efforts have been done to synthesize this new material. Various kinds of synthesized methods have been applied to fabricate carbon nitride films, whereas samples with sufficient amounts of crystallized C3N4 structure or with mechanical properties comparable to the predicted values have not been reported. From the basic of ion-solid interaction, Wang, et al. have proposed a novel method, "low energy ion implantation + swift heavy ion irradiation", for synthesizing compound in atom mixed materials. This method has been used in the present work.
The SiO2 films was firstly implanted by 120 keV C-ions at room temperature (RT) and then irradiated at RT with 4.57 MeV/u Pb ions. The implantation was performed on 200 kV Heavy Ion Implanter (IMP, Lanzhou) to the dose ranging from 2.0×10^17C/cm^2 to 8.6×10^17C/cm^2,The irradiation was performed at CARIL-GANIL,Caen,France to the fluence ranging from 5.0×10^11Pb/cm^2 to 3.8×10^12Pb/cm^2.Some parameters were given in Table 1(TRIM 96 calculation)。
<正>Crystalline SiO2(c-SiO2) samples were firstly implanted at room temperature (RT) with 120 keV Cions and then irradiated at RT with 950 MeV Pb ions. The C-ion irradiation experiments were performed on the 200 kV heavy ion implanter of IMP and the selected implantation doses are 2. 0×1017 , 5. 0×1017, 8. 6×1017 and 1. 2×1017C/cm2. The Pb ion irradiation was carried out at the IRASME (CIRIL-GANIL, Caen) and the irradiation fluencies are 5.0×1011,1. 0×1012 and 1..0×1012 Pb/cm2 , respectively. The chemical bonds formation in the samples was investigated by using a Spectrum GX IR spectroscopy.
Wang ZhiguangZhao ZhimingA. BenyagoubM. ToulemondeSong YinLiu ChunbaoZang HangWei KongfangJin Yunfan
Crystalline SiO2 (c-SiO2) samples were implanted at room temperature (RT) with 120 keV C-ions and the selected implantation doses were 2.0×1017, 5.0×1017, 8. 6×1017 and 1. 2×1017 C/cm2. These samples were annealed in vacuum under 500, 700, 900 and 1 100℃, respectively. The modification of the samples was investigated at RT by using a Spectrum GX IR spectroscopy.
Wang Zhiguang, Zhao Zhiming, Song Yin, Liu Chunbao, Zang Hang, Wei Kongfang and Jin Yunfan
In the present work, we used the technique of “low energy ion implantation + swift; heavy ion irradiation ”to investigate huge electronic excitations induced modification in N-doped graphite-like-carbon.
Experimental results showed that energetic ion induced phase change in a solid could be achieved not only by irradiation at high fluences but also by singe ion induced huge electronic excitations. The phase change produced in the later condition is just along individual ion latent tracks。Poecently, we have proposed a novel technique,“low energy ion implantation + swift heavy ion irradiation”, for synthesizing new structures in atom mixed materials in which more attention was paid to the dense electronic excitations effect induced by theincident ions. In the present work, the technique[2} was used to investigate huge electronic excitations