Patent ID: 7201972

Claim:
A metal thin film comprising: a metal material; and a diamond particle dispersed in the metal material, wherein the metal thin film has a film thickness of 5 nm to 35000 nm, wherein the diamond particle is dispersed almost homogeneously over the direction of the film thickness of the metal thin film, wherein the metal thin film has the diamond particle at a concentration of 1 to 12%, and wherein based on a conversion into a circle having an equivalent area, the diamond particle has a first particle size distribution with respect to a particle size of 16 nm or less, at a number average existence rate of 50% or more; the diamond particle has a particle size distribution with respect to a particle size of 50 nm or more, at a number average existence rate of substantially 0%; and the diamond particle has a particle size distribution with respect to a particle size of 2 nm or less, at a number average existence rate of substantially 0%. and further wherein: the diamond particle has an element composition including 72 to 89.5% of total carbon, 0.8 to 1.5% of hydrogen, 1.5 to 2.5% of nitrogen and 10.5 to 25.0% of oxygen, summing up to 100%, the diamond particle, at the time of being dried and when analyzed by a X-ray diffraction (XD) spectrum analysis using Cu—K α radiation, has the largest peak at a Bragg angle of 43.9° (2 θ±2 °), strong and characteristic peaks at either of Bragg angles of 73.5° and 95°, a significantly biased halo at a Bragg angle of 17°, and essentially no peak at a Bragg angle of 26.5°, the diamond particle has a specific surface area of 1.50×10 5 m 2 /kg or more, wherein all of the surface carbon atoms are substantially bonded with hetero atoms, wherein the diamond particle has a total absorption space of 0.5 m 3 /kg or more.