Enhancement of the Si p-n diode NIR photoresponse by embedding β-FeSi2 nanocrystallites

• DOI: 10.1038/srep14795
• Publication Date: 2015-10-05T11:40:25Z
• Authors: A. V. Shevlyagin; D. L. Goroshko; E. A. Chusovitin; K. N. Galkin; N. G. Galkin; A. K. Gutakovskii
• Keywords: Quantum Efficiency

By using solid phase epitaxy of thin Fe films and molecular beam Si, a p(+)-Si/p-Si/β-FeSi2 nanocrystallites/n-Si(111) diode structure was fabricated. Transmission electron microscopy data confirmed well-defined multilayered with embedded nanocrystallites two typical sizes: 3-4 15-20 nm, almost coherent the Si matrix. The at zero bias conditions exhibited current responsivity 1.7 mA/W, an external quantum efficiency about 0.2%, specific detectivity 1.2 × 10(9) cm Hz(1/2)/W wavelength 1300 nm room temperature. In avalanche mode, reached up to 20 mA/W (2% in terms efficiency) value gain equal 5. obtained indicate that embedding β-FeSi2 into depletion region p-n junction results expansion spectral sensitivity 1600 increase photoresponse by more than orders magnitude comparison conventional junction. Thereby, fabricated combines advantage silicon photodiode functionality simplicity near infrared light detection capability β-FeSi2.