ABSTRACT
This report is based on the rigorous coupled wave theory (RCWA) of the
sub-wavelength grating,has carried on the perfect theory inferential reasoning
regarding the sub-wavelength diffraction grating's diffraction situation, especially has
carried on the detailed inferential reasoning regarding the rectangular trough
sub-wavelength diffraction grating's diffraction, and compiles the corresponding
MATLAB procedure to carry on the computer simulation computation the diffraction
efficiency of the diffraction grating . Through massive theoretical calculation and
analysis the computer simulation result, obtains the diffraction grating diffraction
efficiency not only with the diffraction grating incidence angle, the polarization angle,
the azimuth related, but also related with diffraction grating material, line structure
(cycle, trough depth, duty factor). The present paper has analyzed diffraction grating
each kind of parameter separately to the diffraction efficiency influence, as well as
incident light wave condition regarding diffraction grating diffraction efficiency
influence. Through to affects the big several parameters to carry on the analysis and
the utilization computer simulation computation, obtained the sub-wave length
diffraction grating zero order diffraction efficiency along with each main parameter
change when has the corresponding change rule, thus regarding meets the different
need the Asian wave length diffraction grating to carry on the optimization design.
This topic's work lies in the use coupled wave theory to carry on the massive analyses and the
computation, to affected the sub-wavelength diffraction grating zero order diffraction efficiency
each parameter to carry on the comprehensive analysis, unified the sub-wavelength diffraction
grating the actual production process, removed the influence to be small and the actual
non-influence parameter, had determined affects the sub-wavelength diffraction grating zero order
diffraction efficiency the main parameter, then to affects the big several parameters to carry on the
analysis computation emphatically, obtained the sub-wavelength diffraction grating zero order
diffraction efficiency along with the azimuth change rule, made the sample through the micro
processing craft to confirm the above filter characteristic uniqueness existence, and confirmed
carried on the computation based on the coupled wave theory the computational procedure
accuracy.
Key Word:Sub-wavelength grating , rigorous coupled-wave analysis,
zero-diffraction efficiency, filtration characteristic