NOVELTY - Fine silicon particle (I) covered by an organic thin film that is covalently bound to the surface, is claimed.    USE - (I) is useful in solar cell (claimed).    ADVANTAGE - The method provides high-efficiency silicon solar cell at an extremely low cost.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (1) a method for manufacturing (I) comprising a process of having the surface of (I) reacting with an alkoxysilane compound by dispersing (I) among a chemical absorption liquid produced from a mixture of at least an alkoxysilane compound, a silanol condensation catalyst, and a nonaqueous organic solvent;    (2) a method for manufacturing a solar cell comprising a process to form a paste by mixing into an organic solvent the n-type or p-type fine silicon particles covered by an organic film, including a first reactive functional group covalently bound to the surface and the n-type or p-type fine silicon particles covered by an organic film, including a second reactive functional group covalently bound to the surface, a process of applying it to the surface of a base material, and a process of hardening; and    (3) a solar cell where n-type fine silicon particles (11) covered by a first organic thin film covalently bound to the surface and n-type fine silicon particles covered by a second organic thin film covalently bound to the surface are mixed together and covalently bound to each other via the organic thin films to form a hardened film layer of the n-type fine silicon particles, and p-type fine silicon particles covered by a first organic thin film covalently bound to the surface and p-type fine silicon particles covered by a second organic thin film covalently bound to the surface are mixed together and covalently bound to each other via the organic thin films to form a hardened film layer of the p-type fine silicon particles, and then both fine particle layers form a lamination layer on a glass substrate (14).    DESCRIPTION OF DRAWING(S) - The figure shows a solar cell that uses the fine silicon particle.    n-Type fine silicon particles (11)    Epoxy group (12)    Amino group (13)    Glass substrate (14)    Aluminum film. (18)