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Bistable shape memory actuators were fabricated by microsystem technology processes and characterized with regard to their use in tactile graphic displays. The actuators were realized as sputter-deposited buckled metallic thin-film carriers, having structured Ti-Ni-Cu and Ti-Ni-Hf shape memory alloys on the top and at the bottom, respectively. They were sputtered on wavy-structured substrate and had lateral dimensions ranging from 2.2 to 3.5 mm in width and from 1 to 3 mm in length. The actuators were switched with voltages in the range of 0.2 to 0.8 V and with currents in the range of 0.2 to 0.8 A. A force of 2.2 mN with a displacement of 0.7 mm was reached. To improve the performance further, a special test setup was developed. The bistable actuators in it were sputtered on a planar substrate with lateral dimensions ranging from 6 to 8 mm in width and from 3 to 6 mm in length. These actuators were switched with actuation voltages in the range of 0.6 to 1.6 V and with currents in the range of 0.6 to 1.8 A. Thus, a force of 16 mN with a displacement of 1.2 mm was reached. [2007-0261] Index Terms--Bistable actuators, shape memory alloys (SMAs), tactile display, thin-film actuators.

In neural prosthetic systems, a low-impedance electrode-tissue interface is important for maintaining signal quality for recording, as well as effective charge transfer for stimulation. However, neural microelectrodes often have high impedance due to their small surface areas. In this paper, we present a simple method of increasing their effective surface areas by introducing nanostructures on the electrode sites. The method combines photolithography and electron-beam evaporation with a locally patterned anodized porous alumina template to integrate Au-nanorod arrays on the flexible thin-film microelectrode, which can significantly increase the effective surface area and decrease impedance due to its 3-D and compact nanostructures. Moreover, the geometrical and electrical properties of Au-nanorod electrodes were demonstrated and compared with conventional planar microelectrodes by using a scanning electron microscope and an impedance spectroscopy system. Experimental results showed that approximately 25 times lower interface impedance was achieved for this nanostructured microelectrode. Such Au-nanorod integrated microelectrode arrays will be a promising tool for neural engineering. [2008-0136] Index Terms--Electron-beam evaporation, flexible, neural electrode, porous alumina.

The lamination of the core in thin film magnetic components is necessary to reduce the eddy current losses of the structure at high frequencies. The usual way to achieve lamination of the core is by physical vapor deposition (PVD) techniques. These methods are however costly and the deposition of layers is non selective. In this article, an almost entirely aqueous-based electrochemical process for the lamination of magnetic cores is presented. The process uses an electrodepositable photoresist Eagle 2100 ED codeposited with a catalyst (palladium). The Eagle layer is left as an insulator and the catalyst allows the activation of the layer for subsequent metallization. The process can be reproduced as many times as required for producing the multilayers. It is also selective: it does not require multiple photolithography steps. As a demonstration of the multilayer process, a core constituted of two layers of [Ni.sub.80] [Fe.sub.20] (6 [micro]m each layer), separated by an Eagle insulating layer, electroplated over three-dimensional structures, was produced. [1344] Index Terms--Electrodeposition, electrophoretic photoresist, lamination, magnetic, microtransformer, muitilayer.