RAMO4 substrate

A RAMO4 substrate comprising a RAMO4 base material part containing a single crystal represented by the general formula RAMO4, where R represents one or a plurality of trivalent elements selected from a group of elements including:

• Sc, In, Y, and a lanthanoid element, A represents one or a plurality of trivalent elements selected from a group of elements including:
• Fe(III), Ga, and Al, and M represents one or a plurality of divalent elements selected from a group of elements including:
• Mg, Mn, Fe(II), Co, Cu, Zn, and Cd, wherein:
• the RAMO4 base material part has a beveled portion at an edge portion of the RAMO4 base material part,
• the RAMO4 base material part has a principal surface having an off angle θ with respect to a cleavage surface of the single crystal,
• the beveled portion contains a first region having an angle θ1 with respect to the principal surface, and a second region formed outside the first region, having an angle θ2 with respect to the principal surface, and
• the angles θ, θ1, and θ2 satisfy the relationship θ1<θ<θ2.