Résumé
A new fluorescent silsequioxane precursor with tuned optical properties and controlled aggregation properties is designed. The two cyclohexyl moieties introduced in the molecular structure allow the formation of very good quality films. The J-aggregated structure is transcribed into the solid by photoacidcatalyzed hydrolysis–polycondensation. Aggregation of the chromophores is reducedandhighlyfluorescentmaterials are obtained.The photoacid generator liesonthe surface of thehomogeneouslayer of the sol–gelprecursor. Thisphase separation presents several advantages, including UV protection of the chromophore and easy removal of the PAG. The first example of chemical amplification in the photolithography of the conjugated silsesquioxane precursor is demonstrated. As hydrolysis–polycondensation could be achieved in a controlled way by UV exposure, chemically amplified photolithography is achieved by irradiating a composite film (_110nm thick) on silicon wafer by using a copperTEMgrid as shadowmask. Thepattern is produceduniformly on a miscroscopic scale of 3 mm, the photopatterned pixels remaining highly fluorescent.Thesizes of the photolithographedpixels correspondto the sizes of the rectangular holes of the 300_75 mesh grid (hole: 63 mm_204 mm).