Study On Hybrid Polysiloxane Materials For Waveguides

With the rapid development of science and technology, the optical interconnects solve the bottleneck problem of electrical interconnections. Optical waveguide devices are the bases for the development of optical interconnects, and so the research and development of optical waveguide materials with high performance have become a critical issue. Inorganic-organic hybrid materials have attracted great public attention because the hybrid materials combined the advantages of both inorganic and organic materials. The conventional hydrolytic sol-gel process to synthesis hybrid materials remains to have many serious problems, such as high optical propagation loss and abrupt shrinkage. To solve these problems, this paper prepared a series of hybrid silicone optical waveguide materials by a non-hydrolytic sol-gel process.Firstly, novel fluorinated polysiloxane (FPSQ) waveguides have been synthesized by a non-hydrolytic sol-gel process. The chemicals used are diphenylsilanediol (DPSD), perfluoro-alkylsilane (FAS-17) and 3-methacryl-oxypropyltrimethoxysilane (KH-570) in the synthesis. Structural information was obtained by Nuclear Magnetic Resonance (NMR) and Fourier Transform Infra-Red (FTIR) spectroscopy. Optical propagation loss and refractive index measurements were obtained using a Prism-Coupler. Experimental results show that the introduction of FAS-17 monomer can reduce the optical loss to 0.086dB/cm, but the refractive index is reduced significantly. DSC and TGA were utilized to test the thermal properties of FPSQ materials. The thermal decomposition temperatures for 1% mass loss (Td1%) were higher than 345℃, indicating the great thermostability of FPSQ films for waveguides.To further expand the scope of refractive index, phenyltrimethoxysilane (PTMS) and zirconium n-propoxide (IV) were introduced into the three monomers’system respectively. The optical properties of the three systems were compared with each other. Experimental results demonstrate that both PTMS and TV can increase refractive index and expand the scope of refractive index. When the content of PTMS was added to 5mol%, refractive index increased by 0.01. When the content of IV was added to 0.6mol%, refractive index increases by about 0.03. These show that IV monomer have better effect to improve refractive index. At the same time, the introduction of two monomers does’t increase optical propagation loss. At last, TGA and AFM were used to study the thermal properties and surface properties of the cured films. Experimental results show that both PTMS and IV can improve the thermal properties and the surface roughness was not affected.