title: Enhancement of the Si p-n diode NIR photoresponse by embedding β-FeSi2 nanocrystallites.
abstract: By using solid phase epitaxy of thin Fe films and molecular beam epitaxy of Si, a p(+)-Si/p-Si/β-FeSi2 nanocrystallites/n-Si(111) diode structure was fabricated. Transmission electron microscopy data confirmed a well-defined multilayered structure with embedded nanocrystallites of two typical sizes: 3-4 and 15-20 nm, and almost coherent epitaxy of the nanocrystallites with the Si matrix. The diode at zero bias conditions exhibited a current responsivity of 1.7 mA/W, an external quantum efficiency of about 0.2%, and a specific detectivity of 1.2 × 10(9) cm × Hz(1/2)/W at a wavelength of 1300 nm at room temperature. In the avalanche mode, the responsivity reached up to 20 mA/W (2% in terms of efficiency) with a value of avalanche gain equal to 5. The data obtained indicate that embedding of β-FeSi2 nanocrystallites into the depletion region of the Si p-n junction results in expansion of the spectral sensitivity up to 1600 nm and an increase of the photoresponse by more than two orders of magnitude in comparison with a conventional Si p-n junction. Thereby, fabricated structure combines advantage of the silicon photodiode functionality and simplicity with near infrared light detection capability of β-FeSi2.
authors.affiliation: Institute of Automation and Control Processes FEB RAS, Radio St. 5, 690041 Vladivostok, Russia.
authors.forename: A V
authors.initials: AV
authors.lastname: Shevlyagin
authors.affiliation: Institute of Automation and Control Processes FEB RAS, Radio St. 5, 690041 Vladivostok, Russia.|Far Eastern Federal University, School of Natural Sciences, Sukhanova St. 8, 690950 Vladivostok, Russia.
authors.forename: D L
authors.initials: DL
authors.lastname: Goroshko
authors.affiliation: Institute of Automation and Control Processes FEB RAS, Radio St. 5, 690041 Vladivostok, Russia.
authors.forename: E A
authors.initials: EA
authors.lastname: Chusovitin
authors.affiliation: Institute of Automation and Control Processes FEB RAS, Radio St. 5, 690041 Vladivostok, Russia.|Far Eastern Federal University, School of Natural Sciences, Sukhanova St. 8, 690950 Vladivostok, Russia.
authors.forename: K N
authors.initials: KN
authors.lastname: Galkin
authors.affiliation: Institute of Automation and Control Processes FEB RAS, Radio St. 5, 690041 Vladivostok, Russia.|Far Eastern Federal University, School of Natural Sciences, Sukhanova St. 8, 690950 Vladivostok, Russia.
authors.forename: N G
authors.initials: NG
authors.lastname: Galkin
authors.affiliation: Rzhanov Institute of Semiconductor Physics, SB RAS, Lavrentieva Ave.1, 630090 Novosibirsk, Russia.|Novosibirsk State University, Pirogova St. 2, 630090 Novosibirsk, Russia.
authors.forename: A K
authors.initials: AK
authors.lastname: Gutakovskii