| The rapid development of photonic technology and photonic components in telecom and datacom industries need advanced photic material with low-cost waveguide fabrication urgently.Optical polymer will play a key role in integrated photonics fileld due to their easier processibility and integration over inorganic counterparts.Organic silicone polymers can be viewed as organic-inorganic hybrids that combine many desirable properties of conventional organic and inorganic components,such as good thermal stability,rigidity, transparency to UV and visible light,and photostability.In this thesis,three hybrid materal systems have been developed for waveguides.The first one is solid UV curable polysilisesquoxane(PSQ-S15) derived from phenyltriethoxylsilane andγ-Methacryloxypropyltfimethoxysilane.Films with low surface roughness(Rq＜0.5nm) can be obtained by spin-coating using dimethyl formamide(DMF) as solvent.Curing behavior and optical properties(at 1310nm and 1550nm) are discussed.Double bonds(C=C) and Si-OH as curable chemical groups are introduced to PSQ-S15.The optical losses of the films which are cured with different initiators(BPO or IHT-PI 184) are about 0.60dB·cm-1 at 1550nm and 0.31dB·cm-1 at 1310nm cured films.The refractive indexes of the cured film are 1.535 at 1550nm,and 1.533 at 1310nm,the thermal-optic coefficients are -2.2×10-4℃-1 both at 1310nm and 1550nm,and the birefringence are lower than 0.0005.Besides,the cured films shows outstanding thermal stability(no Tg in the range of 40～300℃,and Td with 1.0wt% weight loss are above 370℃in nitrogen).To overcome possible defect of PSQ-S15 films because of the water absorption as using DMF at spin coating procedure,solvent-free liquid hybrid materials(named as PSQ-LH and PSQ-LL) are prepared base on sol-gel process using phenyltrimethoxylsilane, methyltrimethoxylsilane andγ-methacryloxypropyltrimeth-oxysilane as precursors.PSQ-Ls crack-free films with one to ten or more micrometers thickness which possess low surface roughness(Rq＜0.5nm) can be obtained by spin coating without solvent.The refractive index of PSQ-Ls can be exactly tuned from 1.450 to 1.520 by blending PSQ-LH and PSQ-LL at room temperature.There are there reactive groups in PSQ-Ls,C=C,Si-OH and Si-OCH3.In the simplex photoinitiator curing system,a majority of Si-OCH3 is reserved but hardly find Si-OH in the films which undergo UV curing and thermal curing processes.And the optical loss of the corresponding waveguide film is as low as 0.70dB·cm-1.The curing process is optimized for the simplex photoinitiator system,and the dependence of optical properties on water feed,UV exposure time,thermal curing temperature and time is discussed.Optical losses of cured PSQ-LH films are about 0.70～0.80dB·cm-1 at 1550nm and 0.20～0.30dB·cm-1 and birefringence are lower than 0.0005 at both wavelength.The thermal-optic coefficients are-2.2×10-4℃-1 for PSQ-LL cured films both at 1310nm and 1550nm,and -2.4×10-4℃-1 for PSQ-LH cured films both at 1310nm and 1550nm.In addition,the cured films aren't exist Tg in the range of 40～300℃,and Td with 1.0wt%weight loss are 330～347℃for PSQ-LH films, and 322～328℃for PSQ-LL films in nitrogen.In order to increase refractive index and improve mechanical property of above hybrid materials,three hybrid materials containing bridged structures(P-6FDA,P-DP and P-DHPZ) are synthesized from(6FDA-Si,DP-Si,and DHPZ-Si),diphenylsilanediol andγ-methacryloxypropyltrimethoxysilane respectively.After UV(IHT-PI 184 as photoinitiator) and thermal curing process,the optical losses of P-6FDA,P-DP and P-DHPZ films are 0.39, 0.25,and 0.39dB·cm-1 at 1310nm respectively,and 0.63,0.62 and 0.82dB·cm-1 at 1550nm respectively,the refractive index are 1.525(TE),1.550(TE),and 1.558(TE) at 1310nm respectively,and 1.522(TE),1.548(TE) and 1.556(TE) at 1550nm respectively. Birefringences are＜0.0005,0.0012 and 0.0028 at 1310nm respectively,and＜0.0005,0.0010 and 0.0027 at 1550nm respectively.Three cured films also show outstanding thermal stability (Td with 1.0wt%weight loss are 333℃,334℃and 366℃in nitrogen,and no Tg in the range of 40～300℃).PSQ-Ls material system can satisfy requirements for integrated optical waveguide. Conventional lithographic patterning,hard nanoimprint and soft nanoimprint are applied to fabricate optical waveguides using PSQ-Ls.And high quality sidewalls of waveguides are obtained,and achieve propagation light by a straight waveguide.In addition,PSQ-Ls also applied to fabricate Fabry-Perot fiber pressure sensor successfully.
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