Tunable capacitor using electrowetting phenomenon

A tunable capacitor comprising:

• a first electrode;
• a second electrode which is spaced apart from the first electrode and faces the first electrode;
• a fluidic channel which is formed between the first and second electrodes;
• a nonconductive fluid which is disposed in the fluidic channel and moves along the fluidic channel when a direct current (DC) potential difference occurs between the first and second electrodes;
• a first alternating current (AC) electrode which is formed between two of the first electrodes;
• and
• a second AC electrode which is formed between two of the second electrodes to face the first AC electrode;
• wherein each of the first and second electrodes comprises a plurality of electrodes.

A tunable capacitor comprising:

• a first electrode;
• a second electrode which is spaced apart from the first electrode and faces the first electrode;
• a fluidic channel which is formed between the first and second electrodes;
• and
• a nonconductive fluid which is disposed in the fluidic channel and moves along the fluidic channel when a direct current (DC) potential difference occurs between the first and second electrodes, wherein the fluidic channel is in a ring shape with both ends connected to each other, and
• a part of the ring-shaped fluidic channel, where the nonconductive fluid moves, is wider than other parts.

A tunable capacitor comprising:

• a first electrode;
• a second electrode which is spaced apart from the first electrode and faces the first electrode;
• a fluidic channel which is formed between the first and second electrodes;
• a nonconductive fluid which is disposed in the fluidic channel and moves along the fluidic channel when a direct current (DC) potential difference occurs between the first and second electrodes;
• and
• at least one fluid movement preventer which restricts movement of the nonconductive fluid in the fluidic channel.