Ge self-assembled quantum dots （SAQDs） are grown with a self-assembled UHV/CVD epitaxy system. Then, the as-grown Ge quantum dots are annealed by ArF excimer laser. In the ultra-shot laser pulse duration, -20ns, bul...Ge self-assembled quantum dots （SAQDs） are grown with a self-assembled UHV/CVD epitaxy system. Then, the as-grown Ge quantum dots are annealed by ArF excimer laser. In the ultra-shot laser pulse duration, -20ns, bulk diffusion is forbidden,and only surface diffusion occurs, resulting in a laser induced quantum dot （LIQD）. The diameter of the LIQD is 20-25nm which is much smaller than the as-grown dot and the LIQD has a higher density of about 6 ×10^10cm^-2. The surface morphology evolution is investigated by AFM.展开更多
The diffusion and the activation of phosphorus in phosphorus and fluorine co-implanted Ge after being annealed by excimer laser are investigated.The results prove that the fluorine element plays an important role in s...The diffusion and the activation of phosphorus in phosphorus and fluorine co-implanted Ge after being annealed by excimer laser are investigated.The results prove that the fluorine element plays an important role in suppressing phosphorus diffusion and enhancing phosphorus activation.Moreover,the rapid thermal annealing process is utilized to evaluate and verify the role of fluorine element.During the initial annealing of co-implanted Ge,it is easier to form high bonding energy FnVm clusters which can stabilize the excess vacancies,resulting in the reduced vacancy-assisted diffusion of phosphorus.The maximum activation concentration of about 4.4 ×10^(20) cm^(-3) with a reduced diffusion length and dopant loss is achieved in co-implanted Ge that is annealed at a tailored laser fluence of 175 mJ/cm^(2).The combination of excimer laser annealing and co-implantation technique provides a reference and guideline for high level n-type doping in Ge and is beneficial to its applications in the scaled Ge MOSFET technology and other devices.展开更多
A method to improve Ge n＋/p junction diode performance by excimer laser annealing （ELA） and epitaxial Si passi- vation under a low ion implantation dose is demonstrated. The epitaxial Si passivation layer can unpin...A method to improve Ge n＋/p junction diode performance by excimer laser annealing （ELA） and epitaxial Si passi- vation under a low ion implantation dose is demonstrated. The epitaxial Si passivation layer can unpin the Fermi level of the contact of Al/n-Ge to some extent and reduce the contact resistance. In addition, the fabricated Ge n ：/p junction diode by ELA plus epitaxial Si passivation exhibits a decreased reverse current density and an increased forward current density, resulting in a rectification ratio of about 6.5 x 10^6 beyond two orders magnitude larger than that by ELA alone. The reduced specific contact resistivity of metal on n-doped germanium and well-behaved germanium n＋/p diode arc beneficial for the performance improvement of Ge n-MOSFETs and other opto-electronic devices.展开更多
利用Kr F准分子激光器晶化非晶硅薄膜,研究了不同的激光能量密度和脉冲次数对非晶硅薄膜晶化效果的影响。利用X射线衍射(XRD)和扫描电子显微镜(SEM)对晶化前后的样品的物相结构和表面形貌进行了表征和分析。实验结果表明,在激光频率为1...利用Kr F准分子激光器晶化非晶硅薄膜,研究了不同的激光能量密度和脉冲次数对非晶硅薄膜晶化效果的影响。利用X射线衍射(XRD)和扫描电子显微镜(SEM)对晶化前后的样品的物相结构和表面形貌进行了表征和分析。实验结果表明,在激光频率为1 Hz的条件下,能量密度约为180 m J/cm2时,准分子激光退火处理实现了薄膜由非晶结构向多晶结构的转变;当大于晶化阈值180 m J/cm2小于能量密度230 m J/cm2时,随着激光能量密度增大,薄膜晶化效果越来越好;激光能量密度为230 m J/cm2时,晶化效果最好、晶粒尺寸最大,约60 nm,并且此时薄膜沿Si(111)面择优生长;脉冲次数50次以后对晶化的影响不大。展开更多
文摘Ge self-assembled quantum dots （SAQDs） are grown with a self-assembled UHV/CVD epitaxy system. Then, the as-grown Ge quantum dots are annealed by ArF excimer laser. In the ultra-shot laser pulse duration, -20ns, bulk diffusion is forbidden,and only surface diffusion occurs, resulting in a laser induced quantum dot （LIQD）. The diameter of the LIQD is 20-25nm which is much smaller than the as-grown dot and the LIQD has a higher density of about 6 ×10^10cm^-2. The surface morphology evolution is investigated by AFM.
基金Project supported by the National Natural Science Foundation of China(Grant No.61904155)the Science and technology Project of Fujian Provincial Department of Education,China(Grant No.JAT200484)+1 种基金the Natural Science Foundation of Fujian Province,China(Grant No.2018J05115)the Scientific Research Projects of Xiamen University of Technology,China(Grant No.YKJCX2020078).
文摘The diffusion and the activation of phosphorus in phosphorus and fluorine co-implanted Ge after being annealed by excimer laser are investigated.The results prove that the fluorine element plays an important role in suppressing phosphorus diffusion and enhancing phosphorus activation.Moreover,the rapid thermal annealing process is utilized to evaluate and verify the role of fluorine element.During the initial annealing of co-implanted Ge,it is easier to form high bonding energy FnVm clusters which can stabilize the excess vacancies,resulting in the reduced vacancy-assisted diffusion of phosphorus.The maximum activation concentration of about 4.4 ×10^(20) cm^(-3) with a reduced diffusion length and dopant loss is achieved in co-implanted Ge that is annealed at a tailored laser fluence of 175 mJ/cm^(2).The combination of excimer laser annealing and co-implantation technique provides a reference and guideline for high level n-type doping in Ge and is beneficial to its applications in the scaled Ge MOSFET technology and other devices.
基金Project supported by the High Level Talent Project of Xiamen University of Technology,China(Grant No.YKJ16012R)
文摘A method to improve Ge n＋/p junction diode performance by excimer laser annealing （ELA） and epitaxial Si passi- vation under a low ion implantation dose is demonstrated. The epitaxial Si passivation layer can unpin the Fermi level of the contact of Al/n-Ge to some extent and reduce the contact resistance. In addition, the fabricated Ge n ：/p junction diode by ELA plus epitaxial Si passivation exhibits a decreased reverse current density and an increased forward current density, resulting in a rectification ratio of about 6.5 x 10^6 beyond two orders magnitude larger than that by ELA alone. The reduced specific contact resistivity of metal on n-doped germanium and well-behaved germanium n＋/p diode arc beneficial for the performance improvement of Ge n-MOSFETs and other opto-electronic devices.
文摘利用Kr F准分子激光器晶化非晶硅薄膜,研究了不同的激光能量密度和脉冲次数对非晶硅薄膜晶化效果的影响。利用X射线衍射(XRD)和扫描电子显微镜(SEM)对晶化前后的样品的物相结构和表面形貌进行了表征和分析。实验结果表明,在激光频率为1 Hz的条件下,能量密度约为180 m J/cm2时,准分子激光退火处理实现了薄膜由非晶结构向多晶结构的转变;当大于晶化阈值180 m J/cm2小于能量密度230 m J/cm2时,随着激光能量密度增大,薄膜晶化效果越来越好;激光能量密度为230 m J/cm2时,晶化效果最好、晶粒尺寸最大,约60 nm,并且此时薄膜沿Si(111)面择优生长;脉冲次数50次以后对晶化的影响不大。
