Ultrasonic vibration sub-element and ultrasound probe

An ultrasonic vibration sub-element, comprising:

• a substrate;
• a ground layer, disposed on the substrate;
• a first insulation layer, wherein the ground layer is disposed between the substrate and the first insulation layer;
• a second insulation layer, wherein the first insulation layer is disposed between the ground layer and the second insulation layer;
• a first electrode layer, configured to receive a direct current voltage, wherein the second insulation layer is disposed between the first insulation layer and the first electrode layer;
• a third insulation layer, wherein the first electrode layer is disposed between the second insulation layer and the third insulation layer;
• and
• a second electrode layer, configured to receive an alternating current signal and disposed between the second insulation layer and the third insulation layer,
• wherein before the ultrasonic vibration sub-element is driven, there is a cavity between the first insulation layer and the second insulation layer,
• wherein when the ultrasonic vibration sub-element is driven, the first electrode layer receives the direct current voltage and is configured to at least drive the second insulation layer to shrink toward the cavity, and the second electrode layer receives the alternating current signal and is configured to at least drive the third insulation layer to vibrate.