A sintered body for bonding a semiconductor device component, which is obtained by fusing copper fine particles having a primary particle diameter of 1 to 300 nm by a sintering temperature at 200°C to 350°C and composited with an organic compound containing polyethylene oxide having 8 to 200 carbon atoms, wherein when a Vickers hardness of the sintered body at 150°C is set as Hvb and a Vickers hardness of the same sintered body at 25°C is set as Hva, a value of (Hvb/Hva) × 100 (%) is 5% or more and 20% or less, wherein the Vickers hardness was evaluated as specified in the description, wherein the organic compound is a thioether compound according to one of Formulae to W-(OCH 2 CH 2) n -O-CH 2 -CH -CH 2 -S-X, [W-(OCH 2 CH 2) n -O-CH 2 -CH -CH 2 -S-] d Y, [W-(OCH 2 CH 2) n -O-CH 2 -CH -CH 2 -S-R a -] t Z, wherein, in Formulae,, and, W is a C 1 -C 8 alkyl group and n is an integer representing the repeating number of 4 to 100; X is a C 2 -C 12 alkyl group, an allyl group, an aryl group, an arylalkyl group, -R 1 -OH, -R 1 -NHR 2, or -R 1 -(COR 3) m, where R 1 is a C 1 -C 4 saturated hydrocarbon group, R 2 is a hydrogen atom, a C 2 -C 4 acyl group, a C 2 -C 4 alkoxycarbonyl group, or a benzyloxycarbonyl group which may have a C 1 -C 4 alkyl group or a C 1 -C 8 alkoxy group as a substituent on an aromatic ring, R 3 is a hydroxy group, a C 1 -C 4 alkyl group, or a C 1 -C 8 alkoxy group, and m is an integer of 1 to 3; Y is a divalent to tetravalent group in which a carbon atom is directly bonded to a sulfur atom, and is a C 1 -C 4 saturated hydrocarbon group or a group in which two or three C 1 -C 4 saturated hydrocarbon groups are linked by -O-, -S-, or -NHR b -, where R b is a C 1 -C 4 saturated hydrocarbon group, and d is an integer of 2 to 4; and, R a is a C 2 -C 5 alkylcarbonyloxy group, Z is a divalent to hexavalent group in which a carbon atom is directly bonded to a sulfur atom, and is a C 2 -C 6 saturated hydrocarbon group, an isocyanuric acid-N,N',N"-triethylene group, or a group in which two or three C 2 -C 6 saturated hydrocarbon groups are linked by -O-, -S-, or -NHR c - where R c is a C 1 -C 4 saturated hydrocarbon group, and t is an integer of 2 to 6, wherein the concentration of said thioether-type organic compound is 0.3% to 10% by mass. wherein when a Vickers hardness of the sintered body at 150°C is set as Hvb and a Vickers hardness of the same sintered body at 25°C is set as Hva, a value of (Hvb/Hva) × 100 (%) is 5% or more and 20% or less, wherein the Vickers hardness was evaluated as specified in the description, wherein the organic compound is a thioether compound according to one of Formulae to W-(OCH 2 CH 2) n -O-CH 2 -CH -CH 2 -S-X, [W-(OCH 2 CH 2) n -O-CH 2 -CH -CH 2 -S-] d Y, [W-(OCH 2 CH 2) n -O-CH 2 -CH -CH 2 -S-R a -] t Z, wherein, in Formulae,, and, W is a C 1 -C 8 alkyl group and n is an integer representing the repeating number of 4 to 100; X is a C 2 -C 12 alkyl group, an allyl group, an aryl group, an arylalkyl group, -R 1 -OH, -R 1 -NHR 2, or -R 1 -(COR 3) m, where R 1 is a C 1 -C 4 saturated hydrocarbon group, R 2 is a hydrogen atom, a C 2 -C 4 acyl group, a C 2 -C 4 alkoxycarbonyl group, or a benzyloxycarbonyl group which may have a C 1 -C 4 alkyl group or a C 1 -C 8 alkoxy group as a substituent on an aromatic ring, R 3 is a hydroxy group, a C 1 -C 4 alkyl group, or a C 1 -C 8 alkoxy group, and m is an integer of 1 to 3; R 1 is a C 1 -C 4 saturated hydrocarbon group, R 2 is a hydrogen atom, a C 2 -C 4 acyl group, a C 2 -C 4 alkoxycarbonyl group, or a benzyloxycarbonyl group which may have a C 1 -C 4 alkyl group or a C 1 -C 8 alkoxy group as a substituent on an aromatic ring, R 3 is a hydroxy group, a C 1 -C 4 alkyl group, or a C 1 -C 8 alkoxy group, and m is an integer of 1 to 3; Y is a divalent to tetravalent group in which a carbon atom is directly bonded to a sulfur atom, and is a C 1 -C 4 saturated hydrocarbon group or a group in which two or three C 1 -C 4 saturated hydrocarbon groups are linked by -O-, -S-, or -NHR b -, where R b is a C 1 -C 4 saturated hydrocarbon group, and d is an integer of 2 to 4; and, R a is a C 2 -C 5 alkylcarbonyloxy group, Z is a divalent to hexavalent group in which a carbon atom is directly bonded to a sulfur atom, and is a C 2 -C 6 saturated hydrocarbon group, an isocyanuric acid-N,N',N"-triethylene group, or a group in which two or three C 2 -C 6 saturated hydrocarbon groups are linked by -O-, -S-, or -NHR c - where R c is a C 1 -C 4 saturated hydrocarbon group, and t is an integer of 2 to 6, wherein the concentration of said thioether-type organic compound is 0.3% to 10% by mass.