Presentation Information
[11a-PA6-1]Investigation of Nitrogen Plasma Irradiation Effect on GaN Growth
on ScAlMgO4 Substrate by RF-MBE Technique
〇(P)Earul Islam1, Gentatsuro Hata2, Trang Nakamoto3, Takashi Fujii1,4, Ryuichi Sugie2, Tsutomu Araki2 (1.Ritsumeikan Uni., ROST, 2.Ritsumeikan Uni., Col. of Sci. & Eng., 3.Ritsumeikan Uni., R-GIRO, 4.Fukuda Crystal Lab.)
Keywords:
III-N,Crystal Growth,Nitrogen Plasma
III-N semiconductors are showing superior performance in optical and electronic device applications. But easy access free standing high quality III-N epitaxial layers or substrates fabrication techniques are still immature. ScAlMgO4 (SAM) substrate is promising for III-N growth owing to its low in-plane lattice mismatch (1.8%), compatible thermal expansion coefficients, and reusability. However, challenges such as low growth rate, poor crystal quality, and Mg contamination into III-N still need to be addressed. We prefer low-temperature RF plasma-assisted MBE useful to avoid Mg contamination. Plasma of nitrogen radical (N*) irradiation conditions at the beginning of the growth and expected reduce threading dislocation. We examine simultaneous Gallium (Ga) flux and N* exposure, N* irradiation after and before Ga flux pulse followed by their simultaneous exposure for 2 hours of GaN growth. 2theta-Omega study confirms wurtzite single crystalline growth of GaN. In rocking curve study, the full width half maximum reduces ~41% for N* irradiation before and after Ga flux pulse than that of simultaneous case, indicates better single crystalline growth. Therefore, N* treatment seems effective for better crystallinity of GaN.