Kazuo Nakajima

TL;DR: In this paper, a transparent conductive Sn-doped β-Ga2O3 single crystal with high crystallinity was successfully fabricated as a substrate for the growth of GaN-based compounds.

TL;DR: In this paper, a new concept of growing a polycrystalline Si ingot suitable for solar cells by casting based on the directional growth behavior of polycrystaline Si investigated using an in situ observation system.

TL;DR: In this article, the effect of thermal annealing on the surface morphology, and electrical and optical properties was examined to compared with that before annaling, and the results suggest that Sn-doped β-Ga2O3 single crystal is thermally stable and is useful as substrate for the growth condition of GaN-based compounds.

TL;DR: In this article, the authors investigated the generation mechanism of dislocations by comparing dislocation occurrence in multicrystalline silicon with calculated results of the shear stress on the slip plane by finite element analysis.

TL;DR: In this paper, the performance of solar cells with stacked self-assembled Ge dots in the intrinsic region of Si-based p-i-n diode was investigated and the results showed that electron-hole pairs generated in Ge dots can be efficiently separated by the internal electric field, and can contribute to the photocurrent without considerable recombination in Ge/Si interfaces.