Abstract: A process capable of forming an inorganic film which can be used at a relatively large thickness equivalent to, or greater than, the thickness of an organic SOG, without being subjected to oxidation by O.sub.2 plasma treatment used in a fabrication process of a semiconductor device. Polysilazane is first coated on a base, and the resulting polysilazane film is converted to a silicon dioxide film.

Abstract: Novel polysilphenylenesiloxanes having a three-dimensional mesh structure of silphenylenesiloxane core surrounded by triorganosilyl groups, which have a good sensitivity to ionizing radiations such as deep ultraviolet rays, electron beams and X-rays, a high softening point of 400.degree. C. or more, and a good resistance to O.sub.2 -plasma etching, and exhibit a high contrast and low swelling. These polysiphenylenesiloxanes are useful as a resist material, especially a top layer resist of the bi-level resist system and an interlevel dielectric or heat-resisting protective layer. The resist material has a high resolution because of a high contrast, low swelling and high thermal resistance thereof.

Abstract: Novel polysilphenylenesiloxanes having a three-dimensional mesh structure of silphenylenesiloxane core surrounded by triorganosilyl groups, which have a good sensitivity to ionizing radiations such as deep ultraviolet rays, electron beams and X-rays, a high softening point of 400.degree. C. or more, and a good resistance to O.sub.2 -plasma etching, and exhibit a high contrast and low swelling. These polysiphenylenesiloxanes are useful as a resist material, especially a top layer resist of the bi-level resist system and an interlevel dielectric or heat-resisting protective layer. The resist material has a high resolution because of a high contrast, low swelling and high thermal resistance thereof.

Abstract: A lower alkyl polysilsesquioxane having a general formula ##STR1## wherein R is CH.sub.3 is C.sub.2 H.sub.5, and n is an integer equal to about 50 to about 10,000, prepared by (a) dissolving a lower alkyl trifunctional silane in an organic solvent at a temperature of -31 20.degree. C. to -50.degree. C. to form an organic solution thereof; (b) hydrolyzing the lower alkyl trifunctional silane by dropping water into the organic solution at a temperature of -20.degree. C. to -50.degree. C. under an inert gas pressurized at 1,000 to 3,000 Pa; and (c) gradually heating the organic solution together with a water phase lying therebeneath up to a temperature of 60.degree. C. to 100.degree. C. under an inert gas pressurized at 1,000 to 3,000 Pa.

Abstract: A high-energy radiation-sensitive pattern-forming resist material consisting of polysilsesquioxane having no hydroxyl group in its molecule. The pattern-forming material of this invention has an improved sensitivity to high-energy radiation exposure, a high resistance to dry etching, a high resolution capability, and an improved thermal stability.

Abstract: A lower alkyl polysilsesquioxane having a general formula ##STR1## wherein R is CH.sub.3 or C.sub.2 H.sub.5, and n is an integer equal to about 50 to about 10,000, prepared by (a) dissolving a lower alkyl trifunctional silane in an organic solvent at a temperature of -20.degree. C. to -50.degree. C. to form an organic solution thereof; (b) hydrolyzing the lower alkyl trifunctional silane by dropping water into the organic solution at a temperature of -20.degree. C. to -50.degree. C. under an inert gas pressurized at 1,000 to 3,000 Pa; and (c) gradually heating the organic solution together with a water phase lying therebeneath up to a temperature of 60.degree. C. to 100.degree. C. under an inert gas pressurized at 1,000 to 3,000 Pa.

Abstract: A high-energy radiation-sensitive pattern-forming resist material consisting of polysilsesquioxane having no hydroxyl group in its molecule. The pattern-forming material of this invention has an improved sensitivity to high-energy radiation exposure, a high resistance to dry etching, a high resolution capability, and an improved thermal stability.