A capacitive humidity sensor based on ordered macroporous silicon with thin film surface coating

作者：Wang Yun; Park Seungwoo; Yeow John T W^*; Langner Andreas; Mueller Frank

来源：Sensors and Actuators B: Chemical , 2010, 149(1): 136-142.

DOI：10.1016/j.snb.2010.06.010

• Humidity sensor
• Ordered structure
• Ordered macroporous silicon
• Ta(2)O(5)

In this paper, we report a new approach for humidity sensing. The sensor is based on ordered macroporous silicon with a Ta(2)O(5) thin film coating. The ordered macroporous silicon array has perfectly aligned pores and uniform pore size (4 mu m). The 95 nm Ta(2)O(5) thin film is uniformly deposited on the pore surface by atomic layer deposition (ALD), which acts as an adsorption enhancement layer. The sensor's capacitance is measured to RH changes. The sensor shows very high sensitivity and small hysteresis, especially at high RH levels. It also shows very good repeatability and long term stability.

• 出版日期2010-8-6