[21p-P17-1~26] 13.4 Si wafer processing /Si based thin film /MEMS/Integration technology

[21p-P17-7] Fabrication of n⁺poly-Ge film with high electron concentration and high electron mobility by Flash-lamp annealing (FLA)

〇Masahiro Koike^1,2, Koji Usuda^1,2, Yoshiki Kamata^1,2, Mori Takahiro^2,3, Tatsuro Maeda^2,3, Tsutomu Tezuka^1,2 (1.Toshiba Corp., 2.GNC, AIST, 3.AIST)

Keywords:semiconductor,germanium,anneal

n⁺poly-Ge films were fabricated from amorphous Ge with various doses of P-ion implantation by annealing sequences using combinations of flash lamp annealing (FLA) and conventional furnace annealing (FA). It was clarified that crystallization by FA resulted in p⁺poly-Ge films with high hole concentration (~10¹⁸ cm^-3) originating from acceptor-like defects; on the other hand, activation annealing by FLA resulted in n⁺poly-Ge films with high electron concentration (~10¹⁹ cm^-3). Activation ratios as high as those for crystalline Ge and high electron mobility (>140 cm²/Vs) exceeding the values for crystalline Si were achieved. The origin of these high values in the FLA-activated poly-Ge could be explained by the lower concentration of acceptor-like defects inside grain than that in FA-activated poly-Ge.