MANUFACTURING METHOD OF COMPOSITE SUBSTRATE AND COMPOSITE SUBSTRATE

PROBLEM TO BE SOLVED: To provide a manufacturing method of a composite substrate having a desired warp, and to provide the composite substrate.SOLUTION: A single crystal substrate group 10 which consists of single crystal substrates each having a front face and a rear face is prepared. The single crystal substrate group 10 is so arranged that front faces of the substrates in the single crystal substrate group 10 are inclined to one another. The substrates in the single crystal substrate group 10 are arranged such that their front faces as a whole form either a convex or a concave. The back faces of the substrates in the single crystal substrate group 10 are faced with a base substrate 30. The back faces of the substrates in the single crystal substrate group 10 and the base substrate 30 are bonded together.