Spectral extension of Ge photodiodes via Sn implantation and flashlamp annealing
This solution offers a method to extend the spectral range of Ge photodiodes by implementing Sn implantation and flashlamp annealing, enhancing their responsivity and reducing dark currents. Compatible with CMOS platforms, it targets applications in SWIR sensing.
Overview
This research introduces an innovative process to enhance the spectral range of germanium (Ge) photodiodes through tin (Sn) implantation and flashlamp annealing. The process aims to leverage fully CMOS-compatible fabrication to develop GeSn photodiodes, which boast a cut-off wavelength exceeding 1800 nm. This approach promises high responsivities and low dark currents, making it ideal for short-wave infrared (SWIR) applications.
Technical specifications
The technique involves post-CMOS fabrication steps where Sn is implanted into Ge photodiodes, followed by an annealing process. This method reduces the semiconductor bandgap, shifting the absorption edge to longer wavelengths. Key features include:
- Sn implantation: Adaptation of implantation parameters to suit device requirements.
- Flashlamp annealing: Optimization of annealing parameters, such as temperature and ramp time, to enhance device performance.
- Iterative optimization: Continuous refinement of diode geometry and processing parameters to achieve desired performance metrics.
Technology readiness level
The current technology readiness level is 3, indicating the concept has been experimentally proven in a laboratory setting. Future work will focus on optimizing the implantation and annealing processes to improve device characteristics and validate performance against non-implanted Ge photodiodes.
About Brandenburgische Technische Universität Cottbus
BTU Cottbus–Senftenberg is a public technical university of about 7,500 students with a compact, internationally oriented and strongly practice-focused character. Across three locations in Cottbus and Senftenberg, research laboratories, experimental facilities and a transfer database help companies identify relevant expertise and equipment. Its Technology and Innovation function supports project scoping, partner matching, funding advice, collaboration agreements, patents, licenses and startup formation, while regional industry and research partnerships connect research to Lusatia’s industrial transformation. Research is supported by competitive funding from the DFG, BMBF and BMWK, alongside European and state sources.
delivered to your inbox.