[16a-F204-1~11] 3.15 Silicon photonics

[16a-F204-6] Effect of n-type doping level on direct band gap light emission intensity for asymmetric metal/Ge/metal diodes

〇(D)Takayuki Maekura¹, Chisato Motoyama¹, Kentaro Tanaka¹, Keisuke Yamamoto¹, Hiroshi Nakashima², Dong Wang¹ (1.I-Eggs, Kyushu Univ., 2.GIC, Kyushu Univ.)

Keywords:Optical interconnection, Ge light source

We investigated the effect of n-type doping level on light intensity of direct band gap (DBG) electroluminescence (EL) for fin type asymmetric metal/Ge/metal (MGM) diodes. To obtain a doping level of 10¹⁸ cm^-3 order, which is commercially unavailable, a n-Ge/p-Ge structure was fabricated by Sb doping on a p-Ge substrate. The doping level of n-Ge layer was controlled by changing the temperature of push diffusion. The MGM diodes were fabricated on the n-Ge layer, for which the DBG EL intensity was positively dependent on doping level until doping level of 1.0 x 10¹⁸ cm^-3, owing to the increase in electron population in direct conduction band.