Ferroelectric thin film coated substrate, producing method thereof and capacitor structure element using thereof

A method of producing a ferroelectric thin film coated substrate, comprising:

• the first step of forming a metal oxide buffer layer on a substrate;
• the second step of forming a first ferroelectric thin film with a first film thickness, which is crystalline, on said metal oxide buffer layer at a first substrate temperature;
• and
• the third step of forming a second ferroelectric thin film with a second film thickness thicker than the first film thickness on said first ferroelectric thin film at a second substrate temperature which is lower than the first substrate temperature.

A capacitor structure element, comprising:

• a substrate;
• a metal oxide buffer layer formed on said substrate;
• a first ferroelectric thin film with a first film thickness, which is crystalline, formed on said metal oxide buffer layer at a first substrate temperature;
• a second ferroelectric thin film with a second film thickness thicker than the first film thickness, said second ferroelectric thin film being formed on said first ferroelectric thin film at a second substrate temperature lower than the first substrate temperature;
• a lower electrode made of a conductive material formed between said substrate and said metal oxide buffer layer;
• and
• an upper electrode made of a conductive material formed on said second ferroelectric thin film.

A ferroelectric thin film coated substrate, comprising:

• a substrate;
• a metal oxide buffer layer formed on said substrate;
• a first ferroelectric thin film formed on said metal oxide buffer layer, said first ferroelectric thin film being crystalline;
• and
• a second ferroelectric thin film with a film thickness thicker than that of said first ferroelectric thin film, said second ferroelectric thin film formed on said first ferroelectric thin film, said second ferroelectric thin film being crystalline and partially amorphous.