Figure 1: Ge-dot phototransistors (PTs) have a self-organized, gate-stacking heterostructure of a SiO2/Ge-dot/SiO2/SiGe-channel, which is simultaneously produced in a single oxidation step. | Scientific Reports

Figure 1: Ge-dot phototransistors (PTs) have a self-organized, gate-stacking heterostructure of a SiO2/Ge-dot/SiO2/SiGe-channel, which is simultaneously produced in a single oxidation step.

From: High Photoresponsivity Ge-dot PhotoMOSFETs for Low-power Monolithically-Integrated Si Optical Interconnects

Figure 1

Cross-sectional scanning electron microscopic micrographs and 3D schematic diagrams of Ge-dot PTs with (a) tox = 3.5 nm and (b) tox = 38.5 nm showing our ability to precisely control the sizes of the Ge nanodots and the thicknesses of the SiO2 gate oxide. Notably, there exists a 3.5 nm-thick interfacial layer of SiO2 surrounding the Ge dots as a result of an exquisitely-controlled dynamic balance between the fluxes of oxygen and silicon interstitials. (c) EDX elemental x-ray mapping micrographs of a SiO2/Ge-QD/SiO2/SiGe-shell heterostructure over the Si substrate.

Back to article page