Optical Isolator with Si Guiding Layer Fabricated by Photosensitive Adhesive Bonding

Abstract

An optical isolator employing a nonreciprocal guided-radiation mode conversion is described. The optical isolator composes of a magneto-optic waveguide with a Si guiding layer, which can be realized by photosensitive adhesive bonding. The optical isolator was designed at a wavelength of 1.55 μm. Relationship of waveguide parameters was clarified for isolator operation. Dependence of the thickness of an adhesive layer was investigated for the design of the optical isolator.

Photosensitive adhesive bonding process of magnetooptic waveguides with Si guiding layer for optical nonreciprocal devices

“…Therefore, by this technique, the adhesive layer thickness can be reduced to below 1 µm. The result is clearly different from those obtained by Yokoi et al, 7) owing to the difficulty in the bonding process control. Besides the bonding process, waveguide length should also be taken into account since it is an important parameter to determine isolation ratio resulting from attenuation in the waveguide.…”

“…widths. The graph exhibits similar profiles to those reported previously by Yokoi et al 7) The significance of the practical gap width must be discussed on the basis of this figure.…”

“…The proposed optical isolator needs a layer of the adhesive material for bonding the magnetic garnet onto the Si guiding layer. TMMR N-A1000 7) and a thinner are used as the photosensitive adhesive material and diluent, respectively. The temperature and pressure for bonding are approximately 160 °C and 600 g=cm 2 , respectively.…”

“…Ghosh et al 6) studied the SOI waveguide optical isolator of the Mach-Zehnder Interferometer (MZI) type using divinylsiloxanebis-benzocyclobutene (DVS-BCB) as an adhesive material for bonding the magnetic garnet on the silicon waveguide. Yokoi et al 7) proposed the fabrication of a magnetooptic waveguide in the optical isolator using a TMMR N-A1000 photosensitive adhesive from Tokyo Ohka Kogyo. The optical isolator is composed of a straight rib waveguide with a cerium-substituted yttrium iron garnet (Ce:YIG)=Si=SiO 2 structure.…”

Fabrication Processes of SOI Structure for Optical Nonreciprocal Devices

“…S. Ghosh et al [10] studied the SOI waveguide optical isolator of the Mach-Zehnder Interferometer (MZI) type by using divinylsiloxanebis -benzocyclobutene (DVS-BCB) as an adhesive material for bonding magnetic garnet on the silicon waveguide. H. Yokoi et al [11] proposed the magneto-optic waveguide in the optical isolator using TMMR N-A1000 photosensitive adhesive from TOKYO OHKA KOGYO Co. Ltd. Moreover, The SOI optical waveguide is also studied with surface activated bonding technique.…”