The effect of the frequency and power of the bias applied to the substrate on plasma properties in 60 MHz（VHF） magnetron sputtering was investigated.The plasma properties include the ion velocity distribution funct...The effect of the frequency and power of the bias applied to the substrate on plasma properties in 60 MHz（VHF） magnetron sputtering was investigated.The plasma properties include the ion velocity distribution function（IVDF）,electron energy probability function（EEPF）,electron density ne,ion flux Γi,and effective electron temperature Teff.These parameters were measured by a retarding field energy analyzer and a Langmuir probe in the 60 MHz magnetron sputtering,assisted with 13.56 MHz or 27.12 MHz substrate bias.The 13.56 MHz substrate bias led to broadening and multi-peaks IVDFs,Maxwellian EEPFs,as well as high electron density,ion flux,and low electron temperature.The 27.12 MHz substrate bias led to a further increase of electron density and ion flux,but made the IVDFs narrow.Therefore,the frequency of the substrate bias was a possible way to control the plasma properties in VHF magnetron sputtering.展开更多
Ions bombardment is very important in thin films and surface processing. The ion energy and ion flux are two important parameters in ion bombardment. The ion current density mainly dependent on the plasma density give...Ions bombardment is very important in thin films and surface processing. The ion energy and ion flux are two important parameters in ion bombardment. The ion current density mainly dependent on the plasma density gives the number of energetic ions bombarding the substrate. The self-bias voltage in plasma sheath accelerates plasma ions towards the substrate. RF discharge can increase plasma density and RF bias can also provide the insulator substrate with a plasma sheath. In order to choose and control ion energy, ion density, the angle of incidence, and ion species, ion beam sources are used. New types of electrodeless ion sources (RF, MW, ECR-MW) have been introduced in detail. In the last, the effects of ion bombardment on thin films and surface processing are presented.展开更多
We have developed a plasma etching simulator to investigate the evolution of pattern profiles in SiO2 material under different plasma conditions. This model focuses on energy and angular dependent etching yield （phys...We have developed a plasma etching simulator to investigate the evolution of pattern profiles in SiO2 material under different plasma conditions. This model focuses on energy and angular dependent etching yield （physical sputtering in this paper）, neutral and ion angular distributions, and reflection of ions or neutrals on the surface of a photoresist or SiO2. The effect of positive charge accumulation on the surface of insulated mask or SiO2 is studied and the charge accumulation contributes to a deflection of ion trajectory. The wafer profile evolution has been simulated using a cellular-automata-like method under radio-frequency （RF） bias and direct-current （DC） bias, respectively. On the basis of the critical role of angular distribution of ions or neutrals, the wafer profile evolution has been simulated for different variances of angles. Observed microtrenching has been well reproduced in the simulator. The ratio of neutrals to ions has been considered and the result shows that because the neutrals are not accelerated by an electric field, their energy is much lower compared with ions, so they are easily reflected on the surface of SiO2, which makes the trench shallower.展开更多
基金supported by National Natural Science Foundation of China(Nos.11275136,10975105)
文摘The effect of the frequency and power of the bias applied to the substrate on plasma properties in 60 MHz（VHF） magnetron sputtering was investigated.The plasma properties include the ion velocity distribution function（IVDF）,electron energy probability function（EEPF）,electron density ne,ion flux Γi,and effective electron temperature Teff.These parameters were measured by a retarding field energy analyzer and a Langmuir probe in the 60 MHz magnetron sputtering,assisted with 13.56 MHz or 27.12 MHz substrate bias.The 13.56 MHz substrate bias led to broadening and multi-peaks IVDFs,Maxwellian EEPFs,as well as high electron density,ion flux,and low electron temperature.The 27.12 MHz substrate bias led to a further increase of electron density and ion flux,but made the IVDFs narrow.Therefore,the frequency of the substrate bias was a possible way to control the plasma properties in VHF magnetron sputtering.
基金The project supported by the National Nature Science Foundation of China(No.19835030)
文摘Ions bombardment is very important in thin films and surface processing. The ion energy and ion flux are two important parameters in ion bombardment. The ion current density mainly dependent on the plasma density gives the number of energetic ions bombarding the substrate. The self-bias voltage in plasma sheath accelerates plasma ions towards the substrate. RF discharge can increase plasma density and RF bias can also provide the insulator substrate with a plasma sheath. In order to choose and control ion energy, ion density, the angle of incidence, and ion species, ion beam sources are used. New types of electrodeless ion sources (RF, MW, ECR-MW) have been introduced in detail. In the last, the effects of ion bombardment on thin films and surface processing are presented.
基金supported by National Natural Science Foundation of China (Nos.11075029 and 10975030)the Important National Science and Technology Specific Project of China (No.2011ZX02403-001)
文摘We have developed a plasma etching simulator to investigate the evolution of pattern profiles in SiO2 material under different plasma conditions. This model focuses on energy and angular dependent etching yield （physical sputtering in this paper）, neutral and ion angular distributions, and reflection of ions or neutrals on the surface of a photoresist or SiO2. The effect of positive charge accumulation on the surface of insulated mask or SiO2 is studied and the charge accumulation contributes to a deflection of ion trajectory. The wafer profile evolution has been simulated using a cellular-automata-like method under radio-frequency （RF） bias and direct-current （DC） bias, respectively. On the basis of the critical role of angular distribution of ions or neutrals, the wafer profile evolution has been simulated for different variances of angles. Observed microtrenching has been well reproduced in the simulator. The ratio of neutrals to ions has been considered and the result shows that because the neutrals are not accelerated by an electric field, their energy is much lower compared with ions, so they are easily reflected on the surface of SiO2, which makes the trench shallower.
