[15p-2R-1~22] 13.2 Exploratory Materials, Physical Properties, Devices

[15p-2R-17] Control of Electrical Properties of BaSi₂ Thin Films by Alkali-metal-fluoride Treatment

〇Kosuke Hara^1,2, Weijie Du³, Keisuke Arimoto¹, Junji Yamanaka¹, Kiyokazu Nakagawa¹, Kaoru Toko³, Takashi Suemasu^2,3, Noritaka Usami^2,4 (1.Univ. Yamanashi, 2.JST-CREST, 3.Univ. Tsukuba, 4.Nagoya Univ.)

Keywords:Silicide semiconductor,Impurity doping,Alkali metal

We have investigated the alkali-metal doping of BaSi₂ films by means of the deposition of alkali-metal fluorides followed by annealing. It has been found that LiF treatment with annealing at 400 and 500 ^oC enhances electron density up to 10²⁰ cm⁻³ while NaF or KF treatment is not effective for carrier density control. A doping mechanism is proposed based on structural characterization that Li is incorporated into BaSi₂ as a donor at the same time as the dissociation of LiF.