Piezoelectric thick film more than 100 miro-meters deposited by the ultrasonic assisted hydrothermal method

医用超声器件和微压电致动器对压电薄膜的厚度提出了很高的要求。在传统的压电薄膜沉积工艺中，由于600℃以上的高温晶化过程，薄膜内部容易产生裂纹，从而限制了薄膜的厚度。在本研究中，我们重点研究了反应温度为250℃的水热法，通过发展超声波辅助水热法，我们展示了172微米厚的Nb酸钾薄膜。

For medical ultrasonic devices and micro piezoelectric actuators, thick piezoelectric films are strongly demanded. In the conventional piezoelectric film deposition processes, the thickness have been limited because the crack was easily made inside the film due to high temperature crystallization process more than 600 degree C.In this study, we focused on the hydrothermal method whose reaction temperature is 250 degree C. By developing the ultrasonic assisted hydrothermal method, we demonstrated a 172 micrometer thickness of potassium niobate film.