Boron-diffusing source for semiconductor element and diffusing method thereby

Abstract

Abstract PURPOSE:To perform B diffusion in an Si substrate with uniformity and excellent repeatability by using a diffusion source formed of a reaction product of a B compound and a polyalcohol compound and of a solvent. CONSTITUTION:A single polymer or copolymer of HO(C2H4O)nH (n<14), poly- hydroxyalkyl acrylate or methacrylate, polyvinyl butyral, mannitol, etc. are added to boric acid, boric acid anhydride, alkyl boric acid ester, boron chloride or the like and an alcohol solvent such as methylalcohol and glycerin is added thereto. And further, if necessary, an alcohol-soluble metal compound such as phosphoric acid and P2O5 is added thereto, and, through the heat reaction at a temperature of 40 deg.C or more, a sort of boric acid ester is produced and it is applied on the Si substrate by rotation. Subsequently, the solvent is volatilized, an organic part in a film is removed by destructive burning through the heat treatment at the temperature of 500-600 deg.C, thereby an inorganic film of B2O3 is prepared, and further by treating the same at the temperature of 700 deg.C or more, B diffusion is performed. By this method, the uniform and high-density diffusion is performed with ease and with excellent repeatability and in a mass-production manner.

Inventors

• 👤 Akira Hashimoto
• 👤 Muneo Nakayama
• 👤 Toshihiro Nishimura

Bibliographic Details