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Updated: Jun 17, 2026
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Developing High Performance GaP/Si Heterojunction Solar Cells
Published on: November 16, 2018
High-performance self-powered photodetectors based on Te/Si heterojunctions
Quanyu Lu1, Changhui Du1, Yunjie Liu2
1Shandong Key Laboratory of Intelligent Energy Materials, School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China. haolanzhong@upc.edu.cn.
Nanoscale
|June 16, 2026
Summary
High-performance tellurium/silicon (Te/Si) heterojunction photodetectors were fabricated. These devices overcome limitations of pure tellurium, offering high responsivity and detectivity for self-powered, high-speed applications.
Area of Science:
- Materials Science
- Optoelectronics
- Semiconductor Physics
Background:
- Tellurium (Te) shows promise for self-powered photodetectors due to its electrical properties and stability.
- Limitations include high dark current and slow response speeds in pure Te devices, hindering practical use.
Purpose of the Study:
- To develop high-performance Te/Si heterojunction photodetectors.
- To address the limitations of pure Te photodetectors by introducing a built-in electric field.
Main Methods:
- Fabrication of Te/Si heterojunctions using sputtering.
- Deposition of textured Te films onto n-type silicon (n-Si).
- Characterization of photodetector performance under illumination.
Main Results:
- Achieved high responsivity (370 mA W⁻¹) and detectivity (2.08 × 10¹² Jones) at 0 V bias.
- Demonstrated a 3 dB cut-off frequency of ~5 kHz and rapid response times (~135/142 μs).
- Exhibited excellent repeatability and stability in the Te/Si heterojunction photodetectors.
Conclusions:
- Te/Si heterojunctions effectively utilize a built-in electric field to enhance photodetector performance.
- These heterojunctions are suitable for high-performance, self-powered, and high-speed photodetector applications.
- The developed photodetectors show significant potential for advanced optoelectronic systems.
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