Tohru Matsuura

Fabrication of fluorinated polyimide microgrids using magnetically controlled reactive ion etching (MC-RIE) and their applications to an ion drag integrated micropump

Magnetically controlled reactive ion etching (MC-RIE) of a fluorinated polyimide substrate achieved etching selectivity of up to 2600, resulting in a smoothly etched surface and structures hundreds of micrometers high having good perpendicularity. This technique is useful for three-dimensional microfabrication. As an example of a typical application, we fabricated an ion drag integrated micropump with microgrid sets consisting of high pole-shaped counter-electrode elements arranged like a pair of interleaved combs by using a fluorinated polyimide as the structural material, metallization, and lift-off using a ZnO sacrificial layer. This micropump moved ethanol with a flow rate of about when 200 V was applied to the counter electrodes.

Micro-grid fabrication of fluorinated polyimide by using magnetically controlled reactive ion etching (MC-RIE)

A micro grid consisting of 100- mu m-high pole-shaped counterelectrode elements arranged like a pair of interleaved combs was fabricated using a fluorinated polyimide as structural material and metallization and lift-off using a ZnO sacrificial layer. Research into the magnetically controlled reactive ion etching (MC-RIE) of fluorinated polyimide substrate has resulted in an etching selectivity of up to 2600. These conditions result in a smooth etched surface. Shaped constructions hundreds of micrometers high with a good perpendicular shape can be formed using the MC-RIE technique for fluorinated polyimide micro-fabrication. Moreover, many kinds of 3-D structural devices can be manufactured when this technology is combined to a lift-off method using a ZnO sacrificial layer.<<ETX>>

Electrically separated two-axis MEMS mirror array module for wavelength selective switches

A novel two-axis MEMS mirror array module for wavelength selective switches feature a new electrode structure that reduces electrical interference between adjacent channels. The fabricated 50-channel mirror module has good characteristics satisfying system requirements.

Fluorinated polyimide fabrication by magnetically controlled reactive ion etching (MC RIE)

This paper describes the etching rates and morphologies of etched surfaces of fluorinated polyimides having fluorine concentrations, when a magnetic field parallel to the cathode surface was varied during magnetically controlled reactive ion etching (MC RIE). The fluorine concentration of fluorinated polyimides is a key parameter used to control the etching rate in MC RIE and the etching rate can also be increased by applying a high magnetic field. The etching rate was maximum when the fluorine concentration was 15-23 wt%, and the peaks became sharper as the magnetic field increased. The surface morphology also became smoother with increasing magnetic field, and SEM observation revealed that the surface morphology of 23 wt% fluorine polyimide was smoothest when a high etching rate and a high magnetic field were used.

Vibration-proof mechanism design of free-space optical switch modules using MEMS mirror devices for telecom systems

For practical application in a telecommunications system, optical switch modules using MEMS mirror devices should be mechanical-vibration-proof, which is a fundamental environmental reliability criterion. To satisfy this requirement, we propose a design technique for vibration-proof mechanisms. This technique utilizes the dynamic characteristics of each mechanical component and an actual measurement of optical characteristics when mechanical vibration is applied. We evaluated the fundamental environmental characteristics of prototype optical switch modules, such as a wavelength-selectable switch module and a 3-D MEMS optical switch module. The results confirmed that the switching module satisfies the Telcordia GR-63 office vibration test with the application of vibration-proof mechanism, indicating that the MEMS optical switch module is suitable for practical use.

High-aspect-ratio gold electrodes fabricated by thick-multilevel interconnection technology for electrical isolation of MEMS mirrors in wavelength-selective switches

Electrical separation-walls with a high aspect ratio are fabricated in the narrow space between mirror-drive electrodes. With these walls between adjacent channels, each MEMS mirror successfully operates with very low electrical interference.