Semiconductor devices including lower electrodes including inner protective layer and outer protective layer

A semiconductor device comprising:

• a landing pad on a substrate;
• a lower electrode structure including a first lower electrode on the landing pad and a second lower electrode on the first lower electrode;
• a buried layer between the first lower electrode and the second lower electrode;
• a first supporter pattern on a side surface of the lower electrode structure, the first supporter pattern including a supporter hole;
• a dielectric layer on a surface of each of the lower electrode structure and the first supporter pattern;
• and
• an upper electrode on the dielectric layer,
• wherein the first lower electrode includes a first outer protective layer, a first conductive layer between opposing sidewalls of the first outer protective layer, and a first inner protective layer between opposing sidewalls of the first conductive layer,
• wherein the second lower electrode includes a second outer protective layer, a second conductive layer between opposing sidewalls of the second outer protective layer, and a second inner protective layer between opposing sidewalls of the second conductive layer, and
• wherein each of the first outer protective layer and the second outer protective layer comprises titanium oxide, each of the first conductive layer and the second conductive layer includes titanium nitride, and each of the first inner protective layer and the second inner protective layer includes titanium silicon nitride.

A semiconductor device comprising:

• a landing pad on a substrate;
• a lower electrode on the landing pad, the lower electrode including an outer protective layer, a conductive layer having a U-shaped cross-sectional surface between opposing sidewalls of the outer protective layer, and an inner protective layer between opposing sidewalls of the U-shaped cross-sectional surface of the conductive layer;
• a first supporter pattern on a side surface of the lower electrode, the first supporter pattern including a supporter hole;
• a first metal layer between the conductive layer and the first supporter pattern, the first metal layer overlapping the outer protective layer in a vertical direction and including an upper surface at a lower level than an upper surface of the first supporter pattern;
• a dielectric layer on a surface of each of the lower electrode and the first supporter pattern;
• and
• an upper electrode on the dielectric layer,
• wherein the outer protective layer includes titanium oxide, the conductive layer includes titanium nitride, and the inner protective layer includes titanium silicon nitride, and
• wherein, in a horizontal cross-sectional view, the outer protective layer and the first metal layer each have an arc shape and together surround the conductive layer.