Evaluation of Ag diffusion coefficient and control of diffusion depth in MgSi pn-junction diode

Hori, Nobuhiko*; Esaka, Fumitaka  ; Udono, Haruhiko*

Magnesium half silicide is a semiconductor with an indirect energy gap of about 0.6 eV at room temperature. This material is attracting attention as a suitable material for Si-based infrared photo detector. In this study, Ag diffusion coefficient was evaluated for the Ag diffused MgSi substrate using a conventional sputter etching. In addition, the sensitivity of the diode was improved by controlling the Ag diffusion depth. As the result, the sensitivity of the diode with the diffusion depth of 20 m was four times higher than that with the diffusion depth of 80 m.