16:30 〜 16:45
▼ [19p-W834-12] Characterization of Dopant in Individual Si / Ge Core-Shell Nanowires Investigated by Atom Probe Tomography
キーワード：Nanowires,Boron,Atom Probe Tomography
Introduction
In recent years, considerable research has been carried out regarding Si / Ge or Ge / Si core-shell nanowires (NWs) due to their substantial potential in the application of many devices such as metal-oxide field-effect semiconductor transistor and their compatibility with current semiconductor technology [1]. The dopant distributions in the Si / Ge or Ge / Si core-shell NWs directly affect the performance of devices. Therefore, it is important to get clear of the dopant distribution in individual Si / Ge or Ge / Si core-shell NWs.
Laser-assisted atom probe tomography (APT) has proved to be a powerful method to study semiconductor NWs in the atomic-scale resolution [2]. In the previous report, we have report the APT study of B distribution in Ge / Si core-shell NWs [3]. In this study, the B distribution in Si / Ge core-shell NWs was investigated by APT.
Experiment
Si / Ge core-shell NWs were grown on Si (111) substrate by chemical vapor deposition (CVD), with gold nano colloid particles as the catalyst for vapor-liquid-solid (VLS) growth. B atoms were doped during the growth of Si core [4]. Individual Si / Ge core-shell NW specimens for APT analysis were prepared by gallium focused ion beam, with FIB-SEM dual-beam system (Helios NanoLab600i, FEI) as shown in Fig. 1(a). APT analysis was performed using a laser-assisted local electrode atom probe (LEAP4000X HR, AMETEK).
Results
Figures 1(b) and (c) show atom maps of Si / Ge core-shell NW and B distribution in the NW. The Si / Ge core-shell structure was clearly observed in the atom map. Moreover, it was found that B segregated at the Si / Ge interface and B concentration increased gradually from the tip to the bottom of the NW. In this presentation, the details of sample preparation and more analysis data will be shown.
Acknowledgements
The authors would thank N. Ebisawa for the technical support. This work was supported in part by JSAP KAKENHI Grant No. 15H05413.
References
[1] Y. Cui et al., Science 291, 851 (2001).
[2] D. E. Perea et al., Nature Nanotechnol. 4, 315 (2009).
[3] B. Han et al., JSAP Autumn meeting 14P-2Q-9 (2015).
[4] N. Fukata et al., ACS Nano 6, 8887 (2012).
In recent years, considerable research has been carried out regarding Si / Ge or Ge / Si core-shell nanowires (NWs) due to their substantial potential in the application of many devices such as metal-oxide field-effect semiconductor transistor and their compatibility with current semiconductor technology [1]. The dopant distributions in the Si / Ge or Ge / Si core-shell NWs directly affect the performance of devices. Therefore, it is important to get clear of the dopant distribution in individual Si / Ge or Ge / Si core-shell NWs.
Laser-assisted atom probe tomography (APT) has proved to be a powerful method to study semiconductor NWs in the atomic-scale resolution [2]. In the previous report, we have report the APT study of B distribution in Ge / Si core-shell NWs [3]. In this study, the B distribution in Si / Ge core-shell NWs was investigated by APT.
Experiment
Si / Ge core-shell NWs were grown on Si (111) substrate by chemical vapor deposition (CVD), with gold nano colloid particles as the catalyst for vapor-liquid-solid (VLS) growth. B atoms were doped during the growth of Si core [4]. Individual Si / Ge core-shell NW specimens for APT analysis were prepared by gallium focused ion beam, with FIB-SEM dual-beam system (Helios NanoLab600i, FEI) as shown in Fig. 1(a). APT analysis was performed using a laser-assisted local electrode atom probe (LEAP4000X HR, AMETEK).
Results
Figures 1(b) and (c) show atom maps of Si / Ge core-shell NW and B distribution in the NW. The Si / Ge core-shell structure was clearly observed in the atom map. Moreover, it was found that B segregated at the Si / Ge interface and B concentration increased gradually from the tip to the bottom of the NW. In this presentation, the details of sample preparation and more analysis data will be shown.
Acknowledgements
The authors would thank N. Ebisawa for the technical support. This work was supported in part by JSAP KAKENHI Grant No. 15H05413.
References
[1] Y. Cui et al., Science 291, 851 (2001).
[2] D. E. Perea et al., Nature Nanotechnol. 4, 315 (2009).
[3] B. Han et al., JSAP Autumn meeting 14P-2Q-9 (2015).
[4] N. Fukata et al., ACS Nano 6, 8887 (2012).