Sapphire-GaN-based planar integrated free-space optical system.
We report on the design and fabrication of a planar integrated free-space optical system working on the basis of binary phase diffractive optical elements (DOEs) realized in GaN on a sapphire substrate. Group III-nitride/sapphire substrates enable the parallel monolithic integration of passive microoptical elements like lenses and gratings as demonstrated here and optoelectronic devices like light emitters and photodetectors on a single wafer. We present an approach for the simultaneous optimization of the efficiency of transmissive and reflective diffractive optical elements processed in a single lithographic etching step.
Institute of Micro- and Nanotechnologies, Optical Engineering, Technical University Ilmenau, Ilmenau, Germany.
M
M
Hofmann
S
S
Hauguth-Frank
V
V
Lebedev
O
O
Ambacher
S
S
Sinzinger