ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
This article presents an innovative micromachined silicon actuator. A 50-μm-thick silicon foil is anodically bonded onto a broached Pyrex substrate. A free standing membrane and four coplanar electrodes in close proximity are then lithographied and etched. The use of phosphorus doped silicon with low electrical resistivity allows the application of an electrostatic force between one electrode and the moving diaphragm. This plane displacement and the induced interelectrode variation are capacitively detected. Due to the very low electrical resistivity of the doped silicon, there is no need to metallize the vertical trenches of the device. No piezoelectric transducer takes place so that the mechanical device is free from any hysteretic or temperature dependance. The range of the possible actuation along the x and y axis is around 5 μm. The actual sensitivity is xn=0.54 Å/Hz1/2 and yn=0.14 Å/Hz1/2. The microengineering steps and the electronic setup devoted to design the actuator and to perform relative capacitive measurements ΔC/C=10−6 from an initial value C(approximate)10−13 F are described. The elaborated tests and performances of the device are presented. As a conclusion, some experimental projects using this subnanometric sensitive device are mentioned. © 2000 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1150608
Permalink