Oleg G Semyonov

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Recombination of minority carriers in heavily doped n-InP wafers has been investigated using spectral and time-resolved photoluminescence at different temperatures. Studies of the transmitted luminescence were enabled by the partial transparency of the samples due to the Moss–Burstein effect. Temporal evolution of the transmitted luminescence shows(More)
We describe the design, properties, and performance of an excitation-emission (EE) fluorimeter that enables spectral characterization of an object simultaneously with respect to both its excitation and its emission properties. Such devices require two wavelength-selecting elements, one in the optical path of the excitation broadband light to obtain tunable(More)
The shape of the photoluminescence line registered from a side edge of InP wafer is studied as a function of the distance from the excitation spot. The observed redshift in the luminescence maximum is well described by radiation filtering and is consistent with the absorption spectra. Our method provides an independent and accurate determination of the(More)
We study the photoluminescence spectra of n-doped InP bulk wafers, both in the reflection and the transmission geometries relative to the excitation beam. From the observed spectra we estimate the spatial distribution of minority carriers allowing for the spectral filtering due to reabsorption of luminescence in the wafer. This distribution unambiguously(More)
We study the photoluminescence spectra excited at an edge side of n-InP slabs and observed from the broadside. In a moderately doped sample the intensity drops off as a power-law function of the distance from the excitation—up to several millimeters—with no change in the spectral shape. The hole distribution is described by a stationary Lévy-flight process(More)
Keywords: Bulk InP luminescence Thermal degradation Thick epitaxial layers Hydride vapor phase epitaxy Semiconductor scintillators a b s t r a c t Radiative efficiency of highly luminescent bulk InP wafers severely degrades upon heat treatment involved in epitaxial growth of quaternary layers and fabrication of photodiodes on the surface. This unfortunate(More)
Broadband reduction of light reflection from the surface of InP wafers after high-temperature annealing in air has been observed. In the transparency region of the material, the reflection drop is accompanied by increasing transmission of light through the wafer. The spectral position of a deep minimum of the reflection coefficient can be tuned, by varying(More)
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