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Blazed gratings are one of the most significant technology of
diffractive optical elements (DOEs). They are widely adopted
in various
opto-electro-mechanical systems. This dissertation analyzed
blazed gratings by using basic grating theory, color
dispersions. In addition,
multilevel gratings were used to simulate blazed gratings.
Rigorous coupled wave algorithm and Scalar diffraction theory
were used to
calculate the relationship between grating depth and
diffraction efficiency. The optimal gratings were designed
using the methodologies developed.
In addition to develop the design tooling, semiconductor
processing techniques were adopted to fabricate multilevel
gratings during the course
of developing this dissertation. The fabrication processes
include photolithography and etching. In order to fabricate
large area high
performance DOEs, new alignment marks were developed to
minimize alignment errors. The fabrication parameters needed
to precisely control
the etching results were also identified. Once the DOEs were
fabricated, the multilevel gratings manufactured were verified
by measuring surface
profile and diffraction efficiency. The results obtained
verified that the theoretical design matches well with the DOEs
fabricated. These results
verified the applicability of the design and manufacturing
techniques developed in this dissertation.
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