TECHNOLOGY FOCUS - ELECTRONICS - Preferred Component: The substrate is selected from organic electronic apparatus, organic photovoltaic apparatus, dye-sensitized solar cell, bulk heterojunction cell, and light emitting diodes.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The rigid molecule is selected from 3,4,9,10-perylene tetracarboxylic dianhydride and 1,4,5,8-naphthalenetetracarboxylic dianhydride. The sodium alkoxide comprises a long chain alkyl ester. The long chain alkyl ester comprises carbon group selected from methyl group, ethyl group, butyl group, propyl group, a heptyl group, a hexyl group, an octyl group, a nonyl group, and a decyl group. The aromatic diamine is 4,4'-oxydianiline. The alcohol is selected from methanol, ethanol and hexanol. The solvent comprises a polar aprotic solvent. The polar aprotic solvent is selected from dimethyl sulfoxide, N-methyl-2-pyrrolidone, tetrahydrofuran, ethyl acetate, acetone, dimethylformamide, and acetonitrile. Preferred Method: The method (M1) further involves: thermally converting the soluble precursor to an insoluble and infusible rigid molecule; polymerizing the substituted diester diacid of the rigid molecule by reacting the diester diacid of the rigid molecule with an aromatic diamine to form a polyamide-ester; precipitating the polyamide-ester in an alcohol to form a precipitate; re-dissolving the precipitate in a solvent to form a homogeneous polyamide-ester solution; applying the homogeneous polyamide-ester solution to a substrate; heating the substrate to a fixed temperature; and holding the substrate at the fixed temperature for a predetermined amount of time to form a film or a fiber. The polymerization step is a reaction under Yamazaki-Higashi amidation conditions. The fixed temperature is less than 350 degrees C. The re-dissolving step is performed at dissolving temperature of room temperature to 90 degrees C. The increasing the substrate in the heating occurs incrementally. The substrate is held at the fixed temperature for 30 minutes to 240 minutes. The heating step is performed in a vacuum. EXAMPLE - No suitable example given.