NOVELTY - A fullerene derivative (I) is new.    USE - New fullerene derivative is used for manufacture of organic solar cell (all claimed).    ADVANTAGE - The fullerene derivative has high electron mobility and solubility. The safe and efficient organic solar cell having high workability, light efficiency and flexibility is economically manufactured using the fullerene derivative.    DETAILED DESCRIPTION - A fullerene derivative of formula (I) is new.    m,a=0 or 1;    p=1-3;    Cn=60-84C fullerene;    R1-R10=alkyl, cycloalkyl, alkoxy, aryl, aryloxy, t-alkoxy, t-aryloxy, alkyl sulfoxy, aryl sulfoxy, alkenyl, silyl, boron, alkylamine, aralkyl, amine, arylamine, heteroarylamine, aralkyl amine, fluorenyl, carbazole, heterocycyl (all optionally substituted) containing N, O and S, H, D, halo, nitrile, nitro, imide, amide, hydroxyl, ester or carbonyl, where adjacent substituent is bonded with optionally substituted hydrocarbyl to form optionally substituted heterocyclyl containing N, O and S, or adjacent substituent is bonded with substituent in same carbon to form imine, alkenyl (both optionally substituted), spiro bond or carbonyl;    b=1 or 2;    L=1-20C alkylene, 1-20C divalent ether, 5-30C divalent aryl (all optionally substituted) or divalent heteroaryl containing N, O and/or S;    M=group of formula (a)-(d);and    R=alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, arylalkyl, aryloxy, t-alkoxy, t-aryloxy, alkylsulfoxy, arylsulfoxyl, alkenyl, silyl, siloxy, alkylamine, aralkylamine, arylamine, heteroarylamine, aryl, fluorenyl, carbazole, heteroaryloxy comprising N, O and/or S, heteroaryl (all optionally substituted) comprising N, O and/or S, H, D, halo, nitrile, nitro, imide, amide, hydroxy, ester or carbonyl.    (i) When m is 0, at least one of substituent of ring is (L)a-(M)b during formation of the ring with R1-R8 and adjacent substituent of R1-R8; and (ii) When m is 1, at least one of substituent of ring is (L)a-(M)b during formation of ring with R1-R10 and adjacent substituent of R1-R10. INDEPENDENT CLAIMS are included for the following:    (1) organic solar cell, which has primary electrode (102), secondary electrode (105) opposite to primary electrode, and organic layer(s) equipped between primary electrode and secondary electrode. Organic layer(s) contains fullerene derivative; and    (2) manufacture of organic solar cell, which involves preparing substrate (101), forming primary electrode on top of substrate, forming organic layer(s) comprising photoactive layer (104) on top of primary electrode, forming secondary electrode on top of organic layer.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the organic solar cell containing the fullerene derivative.    Substrate (101)    Primary electrode (102)    Hole-transport layer (103)    Photoactive layer (104)    Secondary electrode (105)