In the last two decades there has been growing interest in silicon photonics and in the possibility to integrate new materials to overcome the silicon intrinsic limitations. Erbium has represented a viable solution for the realization of light sources at telecommunications wavelengths opening the path to the investigation of various photonic devices based on rare earth. In this work we investigate a photodetector operating at 1550 nm whose detection mechanism is based on the internal photoemission effect through an Er/Si Schottky junction. The Er/Si junction has been carefully electrically characterized showing a potential barrier and cut-off wavelength of 0.59 eV and 2105 nm, respectively. Moreover, a responsivity of 0.62 mA/W has been measured for a 3 μm-width waveguide at 1550 nm and at reverse voltage of -8 V. Finally, the noise equivalent power of the device has been evaluated as high as 0.53 nW/(Hz)1/2 at -8 V. Even if device responsivity is still low, we believe that our insights may suggest Er/Si as a new platform for the integration of various optical functionalities on the same chip opening new frontiers in the field of low-cost silicon micro and nanophotonics.

中文翻译：

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集成Er / Si肖特基光电探测器在光波导的端面上

在过去的二十年中，人们对硅光子学以及集成新材料以克服硅固有限制的可能性越来越感兴趣。b代表了一种可行的解决方案，用于实现电信波长的光源，这为研究各种基于稀土的光子器件打开了道路。在这项工作中，我们研究了工作在1550 nm处的光电探测器，其检测机制基于通过Er / Si肖特基结的内部光发射效应。已对Er / Si结进行了仔细的电气表征，分别显示出0.59 eV和2105 nm的势垒和截止波长。此外，对于3μm宽度的波导，在1550 nm和反向电压-8 V下的响应度为0.62 mA / W。