Patent ID: 7923906

Claim:
A process for forming a ferroelectric film on a substrate by a sputtering technique, the ferroelectric film containing a perovskite type oxide that is represented by Formula (P) shown below, wherein a target, which has a composition in accordance with the film composition of the ferroelectric film to be formed, and the substrate are located at a spacing from each other, a shield, which surrounds an outer periphery of the target on the substrate side, is located in a non-contact state with respect to the target, the shield being provided with a plurality of shielding layers, which are superposed one upon another at intervals with respect to the direction of the superposition, and the ferroelectric film is formed on the substrate by the sputtering technique under conditions of a height of the shield such that a difference Vs−Vf (V) between a plasma potential Vs (V) in plasma at the time of the film formation by the sputtering technique and a floating potential Vf (V) becomes equal to at most 35V, and under conditions such that a temperature of the substrate becomes equal to at least 400° C.: (Pb 1−x+δ M x ) (Zr y Ti 1−y )O— (P) wherein M represents at least one kind of element selected from the group consisting of Bi and lanthanide elements, x represents a number satisfying the condition of 0.05≦x≦0.4, and y represents a number satisfying the condition of 0<y≦0.7, the standard composition being such that δ=0, and z=3, with the proviso that the value of δ and the value of z may deviate from the standard values of 0 and 3, respectively, within a range such that the perovskite structure is capable of being attained.