Semiconductor device including dielectric layer and method of forming the same

A method of forming a semiconductor device, comprising:

• forming a switching device on a semiconductor substrate;
• forming a pad separation layer on the switching device;
• forming a conductive pad connected to the switching device while extending through the pad separation layer;
• forming a first electrode on the conductive pad;
• forming a dielectric layer on the first electrode;
• and
• forming a second electrode on the dielectric layer,
• wherein the forming a dielectric layer comprises:
• forming a first dielectric layer having a single-crystal perovskite structure on the first electrode;
• and
• forming a second dielectric layer on the first dielectric layer,
• wherein an upper surface of the first dielectric layer adjacent to the second dielectric layer has a greater surface roughness than an upper surface of the second dielectric layer adjacent to the second electrode, and
• wherein the first dielectric layer comprises SrTiO3, SrBaTiO3, CaTiO3, SrZrO3, SrHfO3, LaAlO3, or a combination thereof.

A method of forming a semiconductor device, comprising:

• forming a first electrode having a single-crystal perovskite structure on a single-crystal perovskite strontium titanate (SrTiO3) substrate using a pulsed laser deposition (PLD) method;
• forming a dielectric layer on the first electrode;
• and
• forming a second electrode on the dielectric layer,
• wherein the forming a dielectric layer comprises:
• forming a first dielectric layer having a single-crystal perovskite structure on the first electrode using an atomic layer deposition (ALD) method;
• and
• forming a second dielectric layer on the first dielectric layer,
• wherein an upper surface of the first dielectric layer adjacent to the second dielectric layer has a greater surface roughness than an upper surface of the second dielectric layer adjacent to the second electrode,
• wherein a thickness of the second dielectric layer is 0.05 to 0.3 times a thickness of the first dielectric layer, and
• wherein the dielectric layer has a dielectric constant of 100 to 900.