Polycrystalline diamond and method for manufacturing same, scribe tool, scribe wheel, dresser, rotating tool, wire drawing die, cutting tool, electrode, and processing method using polycrystalline diamond

Polycrystalline diamond having a diamond single phase as basic composition, wherein

• the polycrystalline diamond includes a plurality of crystal grains,
• the polycrystalline diamond contains boron, hydrogen, oxygen, and a remainder containing carbon and trace impurities,
• the boron is dispersed in the crystal grains at an atomic level, and greater than or equal to 90 atomic % of the boron is present in an isolated substitutional type,
• the hydrogen and the oxygen are present in an isolated substitutional type or an interstitial type in the crystal grains,
• each of the crystal grain has a grain size of less than or equal to 500 nm,
• the polycrystalline diamond has a surface covered with a protective film,
• the boron has an atomic concentration of greater than or equal to 1×1014 cm−3 and less than or equal to 1×1022 cm−3,
• the hydrogen has an atomic concentration of greater than or equal to 1×1017 cm−3 and less than or equal to 1×1020 cm−3,
• the oxygen has an atomic concentration of greater than or equal to 1×1017 cm−3 and less than or equal to 1×1020 cm−3,
• in a Raman spectroscopic measurement of the polycrystalline diamond, a peak area around 1575 cm−1±30 cm−1 with a half width of greater than 10 cm−1 and less than or equal to 20 cm−1 is less than 1% of a peak area around 1300 cm−1±30 cm−1 with a half width of less than or equal to 60 cm−1,
• the surface of the polycrystalline diamond has a dynamic friction coefficient of less than or equal to 0.05,
• the protective film contains a BOX cluster, at least one of O and OH that are an oxygen end of the carbon, and a precipitate precipitated out of the crystal grains,
• the protective film has an average film thickness of greater than or equal to 1 nm and less than or equal to 1000 nm,
• the polycrystalline diamond contains a graphene nanoribbon,
• the polycrystalline diamond has a peak at a Raman shift of 1554 cm−1±20 cm−1 with a half width of less than or equal to 10 cm−1 in the Raman spectroscopic measurement, and
• the polycrystalline diamond has a peak at a Raman shift of 2330 cm−1±20 cm−1 with a half width of less than or equal to 6 cm−1 in the Raman spectroscopic measurement, and
• wherein the protective film is a graphene nanoribbon.