Jaguiro Pavel Victorovich, Formation and
properties of porous silicon and avalanche-type light emitting structures based
on it.
Keywords: porous silicon, anodizing,
avalanche breakdown, electroluminescence, quantum efficiency.
The nature of formation and behaviour of porous silicon electroluminescencent
layers are investigated, the manufacture technology is designed, experimental
and theoretical researches of optoelectronic devices on porous silicon are
carried out. The concept of negative interfacial tension on porous silicon is proposed
and its quantity is evaluated. The concept explains stability of cylindrical
porous structure and propagation of pores only in a direction of a pore’s
hemispherical bottom. The analytical expression for pore radius is derived; the
hard dependence of porous silicon parameters from convective transport
conditions is elicited.
The analytical expression for an optical
behavior of porous silicon with taking into account pore structure is obtained.
On its basis the procedure of porous silicon porosity and thickness
measurements by using interference colors is designed.
It is experimentally revealed and
theoretically explored a rather high visible light radiation from microinsular
silicon structures. Is theoretically derived, that the efficiency of a light emission
at avalanche breakdown of silicon structures essentially depends on their
microtopology, being incremented in a series " a plane, cylinder,
sphere" in tens thousand time.
The following parameters are reached:
external quantum efficiency > 0,15 %, luminosity - 200 W/ñì2,
operating speed – few nanoseconds, endurance - more than 1000 hours of
continuous operation. For the first time optoelectronic pair: the porous
silicon light-emitting diode - optical channel - porous silicon photodiode is
explored experimentally.