Hot-rolled copper alloy sheet and sputtering target

A hot-rolled copper alloy sheet comprising:

• 0.2 mass % or more and 2.1 mass % or less of Mg;
• 0.4 mass % or more and 5.7 mass % or less of Al;
• and
• a remainder being Cu and inevitable impurities,
• wherein among the inevitable impurities, an amount of Fe is 0.0020 mass % or less, an amount of O is 0.0020 mass % or less, an amount of S is 0.0030 mass % or less, and an amount of P is 0.0010 mass % or less,
• when measurement is performed in a measurement area of 150000 μm2 or more in a sheet-thickness central portion at a measurement interval of 1 μm by an EBSD method, measurement results are analyzed by data analysis software OIM to obtain a CI value at each measurement point, measurement points where the Cl value is 0.1 or less are removed, an orientation difference between crystal grains is analyzed, and a boundary between adjacent measurement points where an orientation difference between the measurement points is 15° or more is defined as a crystal grain boundary, a special grain boundary length ratio which is a ratio (Lσ/L) of a sum La of lengths of special grain boundaries with 3≤Σ≤29 to a length L of all measured crystal grain boundaries is 20% or more, and
• an average crystal grain size A in the sheet-thickness central portion is 40 μm or less.