Broadband PureB Ge-on-Si Photodiodes

Abstract

Broadband PureB Ge-on-Si photodiodes were fabricated by in-situ capping of n-type Ge-islands grown by chemical-vapor deposition on Si with a 10-nm-thick pure boron layer. Using deposition temperatures from 575C -700C, the B-layer forms p + -like anodes with nmshallow junctions and low dark currents, enabling close to ideal responsivities of 0.13, 0.37, 0.48, and 0.19 A/W at wavelengths 406, 670, 1310 and 1550 nm, respectively.