1 0 0 0 OA Hard x-ray photoelectron spectroscopy study on valence band structure of semiconducting BaSi2
- 著者
- Baba Masakazu Ito Keita Du Weijie Sanai Tatsunori Okamoto Kazuaki Toko Kaoru Ueda Shigenori Imai Yoji Kimura Akio Suemasu Takashi
- 出版者
- American Institute of Physics
- 雑誌
- Journal of applied physics (ISSN:00218979)
- 巻号頁・発行日
- vol.114, no.12, pp.123702, 2013-09
- 被引用文献数
- 15
The valence band structures of a 35-nm-thick BaSi2 epitaxial film on Si(111) have been explored at room temperature by hard x-ray photoelectron spectroscopy (HAXPES). The experimentally obtained photoelectron spectrum is well reproduced by first-principles calculations based on the pseudopotential method. The top of the valence band consists mainly of Si 3s and 3p states in BaSi2, suggesting that the effective mass of holes is small in BaSi2. This is favorable from the viewpoint of solar cell applications. The observed spectrum shifted slightly to the lower energy side due to n-type conductivity of BaSi2. The valence band top was observed at about 0.8 eV below the Fermi level in the HAXPES spectrum.
- 著者
- Baba Masakazu Tsurekawa Sadahiro Watanabe Kentaro Du W. Toko Kaoru Hara Kosuke O. Usami Noritaka Sekiguchi Takashi Suemasu Takashi
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.103, no.14, pp.142113, 2013-09
- 被引用文献数
- 29 3
Potential variations around the grain boundaries (GBs) on the surface in undoped n-BaSi2 epitaxial films on Si(111) and Si(001) were analyzed using Kelvin prove force microcopy. The potentials were higher at GBs than those in the BaSi2 grains on Si(111). The average barrier height was approximately 30 meV at the GBs, indicating that the enhanced potentials repulse photogenerated holes so that the charge carrier recombination can be effectively reduced. In contrast, the potentials were smaller at GBs in the BaSi2 on Si(001), and the average barrier heights were approximately 30 and 50 meV along Si[1–10] and [110], respectively.
- 著者
- Khan M. Ajmal Hara Kosuke O. Nakamura Kotaro Du Weijie Baba Masakazu Toh Katsuaki Suzuno Mitsushi Toko Kaoru Usami Noritaka Suemasu Takashi
- 出版者
- Elsevier B.V.
- 雑誌
- Journal of crystal growth (ISSN:00220248)
- 巻号頁・発行日
- vol.378, pp.201-204, 2013-09
- 被引用文献数
- 18 1
We have successfully grown a-axis-oriented p-type BaSi2 films on Si(111) by in situ boron (B) doping using molecular beam epitaxy (MBE). The hole concentration in B-doped BaSi2 was controlled in the range between 1017 and 1019 cm−3 at room temperature by changing the temperature of the B Knudsen cell crucible. The acceptor level was estimated to be approximately 23 meV.