Fatigue-free bipolar loop treatment to reduce imprint effect in piezoelectric device

A method for preventing degraded device performance of a piezoelectric device, the method comprising:

• operating the piezoelectric device in a performance mode over a first time period by applying one or more voltage pulses greater than or equal to a first amplitude to the piezoelectric device, wherein the first amplitude is greater than an electric coercive field voltage of the piezoelectric device;
• determining that a predetermined threshold value of the performance mode has been reached;
• and
• performing a bipolar loop to the piezoelectric device over a second time period by:
• applying a voltage bias signal across the piezoelectric device at a second amplitude at a first polarity;
• adjusting the voltage bias signal across the piezoelectric device from the second amplitude to a third amplitude at a second polarity opposite to the first polarity, wherein the second amplitude is equal to the third amplitude, and wherein the second amplitude is less than or equal to the electric coercive field voltage of the piezoelectric device;
• and
• adjusting the voltage bias signal across the piezoelectric device from the third amplitude to a fourth amplitude that is between the second amplitude and the third amplitude.

A system, the system comprising:

• a piezoelectric device disposed on a semiconductor substrate, the piezoelectric device comprising a piezoelectric structure disposed between a first electrode and a second electrode;
• bias circuitry electrically coupled to the first electrode and the second electrode, wherein the bias circuitry is configured to operate in a performance mode by applying a voltage bias across the piezoelectric structure;
• measurement circuitry electrically coupled to the bias circuitry, wherein the measurement circuitry is configured to detect that a predetermined threshold value has been reached during the performance mode;
• and
• wherein the bias circuitry is configured to perform a recovery operation upon detection of the predetermined threshold value by:
• increasing the voltage bias from a start value to a first magnitude at a first polarity, decreasing the voltage bias from the first magnitude at the first polarity to the first magnitude at a second polarity opposite to the first polarity, and increasing the voltage bias from the first magnitude at the second polarity to an end value equal to the start value.