Title :
Diamond AFM probe with piezoelectric sensor and actuator
Author :
Shibata, T. ; Unno, K. ; Makino, E.
Author_Institution :
Dept. of Mech. Eng., Ibaraki Univ., Hitachi, Japan
Abstract :
In order to develop a diamond AFM probe with a piezoelectric sensor and actuator, we fabricated lead zirconate titanate (PZT) thin film on a diamond thin film substrate and examined its piezoelectric properties. The PZT thin film was sputtered at room temperature and then annealed in a nitrogen (N/sub 2/) ambient to obtain a perovskite structure. On diamond thin film substrates, the value of piezoelectric constant, d/sub 31/, was as low as about -20 pC/N due to rough surface of the diamond film. After a poling treatment, however, its piezoelectric constant improved to about -65 pC/N. For realization of a PZT sensor and actuator on a diamond cantilever, the PZT thin film was also successfully patterned by reactive ion etching (RIE) in SF/sub 6/ plasma using a Pt upper electrode layer as an etching mask without any damage on a diamond layer. Based on the fabrication and patterning of PZT thin film together with microfabrication techniques of CVD diamond film, we demonstrate the diamond AFM probe of 150 /spl mu/m in length, 50 /spl mu/m in width and 5 /spl mu/m in thickness with a PZT sensor and actuator of 1 /spl mu/m in thickness. The resolution of image sensing and actuation force were estimated to be about 0.4 nm at a resolution of charge measurement of 1/spl times/10/sup -15/ C and 12 /spl mu/N at an applied voltage of 8 V, respectively.
Keywords :
CVD coatings; atomic force microscopy; diamond; dielectric polarisation; image sensors; lead compounds; metallic thin films; microsensors; piezoelectric actuators; piezoelectric thin films; piezoelectricity; probes; rough surfaces; sputter etching; sputtered coatings; 0.4 nm; 1 micron; 150 micron; 293 to 298 K; 5 micron; 50 micron; C; CVD diamond film; PZT; PbZrO3TiO3; Pt electrode layer; RIE; SF/sub 6/ plasma; actuation force; annealing; charge measurement; diamond AFM probe; diamond film; etching; image sensing; lead zirconate titanate; microfabrication techniques; nitrogen; piezoelectric actuator; piezoelectric constant; piezoelectric properties; piezoelectric sensor; poling treatment; reactive ion etching; room temperature; rough surface; sputtered coatings; thin film substrate; Etching; Image resolution; Piezoelectric actuators; Piezoelectric films; Plasma temperature; Probes; Sputtering; Substrates; Thin film sensors; Titanium compounds;
Conference_Titel :
TRANSDUCERS, Solid-State Sensors, Actuators and Microsystems, 12th International Conference on, 2003
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-7803-7731-1
DOI :
10.1109/SENSOR.2003.1215363