Activities (2)
Polymeric and Hybrid Nanocomposites for Microphotonics
Doped  PMMA to increase the refractive index To prepare titanium oxide - polymethylmethacrylate nanocomposites,  the sol-gel process and direct embedded  of titanium oxide nanoparticleswere used. The refractive index increases for the polymer thin films modified with TiO2 compatatively with refractive index of undoped polymer thin films (i.e. by doping with TiO2 the refractive index of PMMA rise from 1.504 to 2.075 at 450 nm).
Experimental refractive index values of PMMA thin film spin coated from 7 %  PMMA  in chlorobenzene  on Si  <100>
Fig. Experimental refractive index values of polyacrylate thin film doped with TiO2 and spin coated on SiO2/ Si
SiO2-TiO2 thin films doped and undoped with Er2O3 were prepared by diping and spinning. After a treatment at high temperatures (30 min. at 900 oC) or at lower temperatures (100 oC), the oxide films were characterised by spectroellipsometrie. Some compositions were selected as matrix for the photonic material thin films doped with rare earth. To generate patterns onto SiO2-TiO2 thin films doped and undoped we used: UV-lithography followed by wet etching; UV-lithography followed by reactive ion etching (RIE);
a)	b)
Refractive index (a) and thickness (b) of SiO2-TiO2 films prepared by diping  on SiO2/Si  (1– 4 layers treated 30 min. at 900 0C)
a	b
SiO2-TiO2 thin films doped with Er2O3 and UV patterned, after etching in:  a - “buffered oxide etch” , b – RIE to obtain micro-ring resonators