الفهرس 
Filters Analysis and DesignOnly 14 pages are availabe for public view
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Abstract
Porous silicon (PS) technology is an interesting technique for the fabrication
of optoelectronic materials with controlled photoluminence and electroluminence
properties. In addition to its compatibility with microelectronic technology, it allows
the flexibility of changing material properties by changing porosity. As the PS layer is
usually formed by electrochemical’ etching of silicon in hydrofluoric acid (HF), the
etching current density controls the porosity, and thus multilayer structures could be
easily formed by changing the current density during the fabrication process. This
motivated a lot of researchers to deveLop different PS based photonic devices. In the
last few years, many active and passive devises have been fabricated based on the PS
technology like: mirrors, interference filters, waveguides, micro cavity resonators,
light emitting diodes (LEDs), optical sensors, biosensors, and chemical sensors. One
of the key optical parameters that can be easily controlled in PS technology over a
wide dynamic range is the material refractive index.
In this work, Optical filters are fabricated with electrochemical etching of
silicon in electrolyte containing hydrofluoric acid and alcohol. The work steps are
first to accurately characterize PS fabricated at various conditions and determine its
optical parameters; then fabricate optical transmission and reflection interference
filters in the near-infrared range with acceptable quality; finally, fitting the
simulations with the measured responses of the fabricated filters.
To obtain high quality devices using porous silicon, a very good control ofthe
etching process is needed, and material homogeneity should be ensured. For this
reason, an electrochemical cell is constructed with certain design, used with a
computer controlled electrical source to control the etching parameters. The effect of
each parameter and some fabrication techniques are studied. We had to ensure the material homogeneity both laterally and in depth, hence some precautions and
fabrication methodology had to be taken into considerations. Also, the problem of
material oxidation and the effect of the stress changing inside the material had to be
studied.