A new and simple cantilever type Pb(Zr, Ti)O3 [PZT] microactuator was fabricated by adopting RuO2. The RuO2 has reasonably good conductivity and stiffness and it can replace the double layer of electrode and supporting layer to a single layer in a cantilever beam. The RuO2, PZT and Al thin films were deposited on the Si substrate. The patterning of the Al was carried out by a lithography process and etched with a chemical wet etchant. The etching of PZT and RuO2 were performed by a reactive ion etching system. The Si was etched isotropically to form a cantilever beam. The fabricated cantilever beam consists of Al, PZT and RuO2, and the thicknesses of the films are 0.40, 0.25 and 0.70 µm, respectively. The beams were from 140 µm to 275 µm in length and all of them were 60 µm wide. Driving tilt angles of the cantilever beams were almost proportional to the applied voltages.

A new thermal neutron beam monitor with a Gas Electron Multiplier (GEM) is developed to meet the needs of the next generation of neutron facilities. A prototype chamber has been constructed with two 100 mm×100 mm GEM foils. Enriched boron-10 is coated on one surface of the aluminum cathode plate as the neutron convertor. 96 channel pads with an area of 8 mm×8 mm each are used for fast signal readout. In order to study the basic characteristics of a boron-coated GEM, several irradiation tests were carried out with α source 239 Pu and neutron source 241 Am(Be). The signal induced by the neutron source has a high signal-to-noise ratio. A clear image obtained from α source 239 Pu is presented, which shows that the neutron beam monitor based on a boron-coated GEM has a good two-dimensional imaging ability. No. 7 ZHOU Jian-Rong et al: Neutron beam monitor based on a boron-coated GEM