PHOTONIC INTEGRATED APPARATUS INCLUDING GERMANIUM

Smart overview of the Invention

The photonic integrated apparatus described involves a layered semiconductor structure aimed at enhancing optical sensing capabilities. It incorporates a first semiconductor layer made of silicon, topped by a second semiconductor layer of germanium. This configuration is designed to generate photocurrent from light received by the silicon layer. A conductive layer with a Schottky junction structure interfaces with the germanium layer, and a tunneling barrier layer is positioned between the germanium and conductive layers.

Technological Context

Photonic integrated circuits are crucial in fields like optical sensors and optical communication, where they integrate various optical elements. Traditional silicon-based photonic devices face challenges in detecting infrared light due to silicon's bandgap limitations. This invention addresses these limitations by incorporating germanium, which allows for infrared light detection, thereby extending the functional range of optical sensors.

Key Features

• The germanium layer can be doped similarly to the silicon layer or remain undoped, with a lower doping concentration than silicon.
• The conductive layer forms a Schottky junction with the germanium layer, and the tunneling barrier layer is essential for reducing dark current.
• The design includes a conductive via and potentially a multi-layer conductive structure to optimize electrical connectivity and performance.

Structural Details

The apparatus includes a substrate and a dielectric layer beneath the silicon layer, which serves as a waveguide. The germanium layer, conductive layer, and tunneling barrier collectively function as a photodetector. The tunneling barrier layer, possibly made of metal oxides like TiO₂ or ZnO, surrounds part of the germanium layer, enhancing the device's efficiency by managing electron flow and minimizing energy losses.

Applications and Variations

While the primary focus is on enhancing photodetection capabilities, the apparatus can integrate additional optical components like light sources and modulators. The described structure allows for flexibility in design, accommodating various optical elements to suit different applications in optical communication and sensor technologies. The detailed configuration ensures that the device can be adapted for diverse functional requirements, offering a robust solution for modern photonic challenges.