Semiconductor Physics, Quantum Electronics & Optoelectronics. 2005. V. 8, N 4. P. 005-013.
Zn and Mn impurity effect on electron and luminescent properties
of porous silicon
V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine,
45, prospect Nauky, 03028 Kyiv, Ukraine
E-mail: pve18@isp.kiev.ua
Abstract. Investigated in this work are por-Si/n-Si structures prepared by anodizing
silicon in 1 % HF water solution, which was followed by natural aging in air and doping
with Zn and Mn impurities. When aging, the oxide film of nanoelements in the above
structures is substituted by a silicate one. Measurements of temperature dependencies
(100...300 K) describing the capacitance photovoltage behavior caused by intense pulses
(∼1021 quanta/cm2
s) of red or white light enabled us to determine the following values
and their changes: the boundary potential for n-Si, distribution of the concentration
inherent to boundary electron states in the n-Si forbidden gap, concentration of traps for
non-equilibrium holes at the interface por-Si/n-Si and in the por-Si layer. The
substitution of the oxide film by the silicate one, the thickness of which can exceed the
initial thickness of the oxide film, makes these structures more stable and results in
sizable changes of spectral dependencies of the short-time (t < 250 ns) and integrated
(t > 250 ns) photoluminescence relaxation components as well as shifts the latter into the
shortwave range.
Keywords: porous silicon, capacitance photovoltage, photoluminescence, doping metal,
boundary electron states, electron traps.
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