Polymer hydrogen silsesquioxane (HSQ) solution in methyl isobutyl ketone (MIBK) commercially known as FOx (flowable oxide) is an alternative material to silicon dioxide obtained by chemical deposition. Standard process to obtain amorphous SiO2 film from polymer HSQ includes: deposition by spin coating, removal of solvent by softbake on hotplate and oxidation of materials by heating in an oven or oxygen plasma treatment. Having parameters similar to those of SiO2, polymer HSQ after softbake is sensitive to an electron beam and also to wavelengths below ? = 157 nm. Due to those factors, it can be used as a high resolution (20 nm details) negative mask in next generation lithography and in e-beam lithography. Removal of FOx after hardbake is possible only with dry etching or in HF solution. The paper reports on possibilities of application of HSQ polymer for integrated optoelectronics. Technology of obtaining an SiO2 layer from HSQ polymer is described. Measurements of thickness, refractive index and transmittance from 200 nm to 800 nm are reported for the fabricated layers.
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