Avalanche Photodiode and Manufacturing Method Thereof

摘要

An avalanche photodiode includes a GeOI substrate; an I—Ge absorption layer configured to absorb an optical signal and generate a photo-generated carrier; a first p-type SiGe layer, a second p-type SiGe layer, a first SiGe layer, and a second SiGe layer, where a Si content in any one of the SiGe layers is less than or equal to 20%; a first SiO2 oxidation layer and a second SiO2 oxidation layer; a first taper type silicon Si waveguide layer and a second taper type silicon Si waveguide layer; a heavily-doped n-type silicon Si multiplication layer; and anode electrodes and a cathode electrode.

主权项

1. An avalanche photodiode (APD) comprising:
a germanium-on-insulator (GeOI) substrate; an intrinsic-germanium (I—Ge) absorption layer disposed on the GeOI substrate and configured to:
absorb an optical signal; andgenerate a photo-generated carrier; a second p-type silicon-germanium (SiGe) layer disposed on the I—Ge absorption layer; a first p-type SiGe layer disposed on the second p-type SiGe layer, wherein a germanium (Ge) content in either the first p-type SiGe layer or the second p-type SiGe layer is less than or equal to 20%; a first silicon dioxide (SiO2) oxidation layer disposed on the GeOI substrate; a second SiO2 oxidation layer disposed on the first SiO2 oxidation layer; a first SiGe layer disposed on the first SiO2 oxidation layer (72); a second SiGe layer disposed on the first SiO2 oxidation layer, wherein a Ge content in either the first SiGe layer or the second SiGe layer is less than or equal to 20%; a first taper type silicon (Si) waveguide layer disposed on the second SiO2 oxidation layer; a second taper type Si waveguide layer disposed on the first SiGe layer; a heavily-doped n-type Si multiplication layer disposed on the second SiGe layer and the first p-type SiGe layer; a cathode electrode is disposed on the heavily-doped n-type Si multiplication layer; and anode electrodes are disposed on the GeOI substrate, wherein the first taper type Si waveguide layer, the second taper type Si waveguide layer, the first SiGe layer, and the second SiGe layer form an evanescent wave coupling structure, wherein the first SiGe layer, the second SiGe layer, the first p-type SiGe layer, and the second p-type SiGe layer form a taper type structure, and wherein the first SiGe layer, the second SiGe layer, the first p-type SiGe layer, the second p-type SiGe layer, and the I—Ge absorption layer form an evanescent wave coupling structure.