Abstract: The present disclosure provides a gallium nitride substrate, where the gallium nitride substrate has a surface having a diameter not less than 50 mm; nine circular regions having a diameter not greater than 1 mm are taken on a surface of the gallium nitride substrate; threading dislocation densities and threading dislocation tilt angles are calculated at the nine circular regions using a multi-photon excitation photoluminescence spectrum; an average value of products of the threading dislocation densities in the nine circular regions and tangent values of the threading dislocation tilt angles is not greater than 1E6 cm?2; and a quotient of a difference between a maximum value and a minimum value of the products of the threading dislocation densities in the nine circular regions and the tangent values of the threading dislocation tilt angles divided by the average value is not greater than 50%.

Abstract: The present disclosure provides a gallium nitride substrate, where the gallium nitride substrate has a surface having a diameter not less than 50 mm; nine circular regions having a diameter not greater than 1 mm are taken on a surface of the gallium nitride substrate; threading dislocation densities and threading dislocation tilt angles are calculated at the nine circular regions using a multi-photon excitation photoluminescence spectrum; an average value of products of the threading dislocation densities in the nine circular regions and tangent values of the threading dislocation tilt angles is not greater than 1E6 cm?2; and a quotient of a difference between a maximum value and a minimum value of the products of the threading dislocation densities in the nine circular regions and the tangent values of the threading dislocation tilt angles divided by the average value is not greater than 50%.