Sample	Heating temperature (K) for 4.20 × 10² s in air	Thickness of films (nm) by TEM observation	Compositional ratio (at%) by EDX		Mass% of oxide films and their crystallite sizes (nm) by XRD*
Sample	Heating temperature (K) for 4.20 × 10² s in air	Thickness of films (nm) by TEM observation	Cu	O	Cu₂O	CuO
1)	523	around 40	90	10	6.0 (19.9)	0.25 (5.1)
2)	573	around 100	85	15	13.2 (17.4)	0.40 (5.6)
3)	623	non-uniform	82	18	22.6 (9.2)	6.05 (3.6)