The Fabrication and Application of a PDMS Micro Through-Holes Mask in Electrochemical Micromanufacturing

The electrochemical micromanufacturing process, as a key micromanufacturing technology, plays an important role in diverse industries. In this paper, polydimethylsiloxane (PDMS) is employed as a mask in the electrochemical micromanufacture of microstructures because of its chemical resistance, low cost, flexibility, and high molding capability. A new method for fabricating a PDMS micro through-holes mask is proposed. In this method, a thin resist film is employed to enhance the adhesion between the substrate and the SU-8 pillar array which is used as a mold. A vacuum-aided process is used to inject the PDMS gel into the SU-8 mold and the PDMS micro through-holes mask can be peeled off from the SU-8 mold when the gel is cured. Experiments were conducted to verify the feasibility of the proposed approach and PDMS microholes of various shapes were obtained. The PDMS mask can then be successfully applied in the electrochemical micromanufacturing process to generate microstructures and microdimple and embossment arrays have been successfully demonstrated. Furthermore, the PDMS mask can be reused, as it is not damaged during the manufacturing process.

Research of Powder Blasting Based Ona New Type PDMS Mask

This paper presents an efficient molding technology to fabricate PDMS mask with the help of precision cutting process. At the same time, we have studied the influence of major parameters on the effect of glass erosion rate in powder blasting process. Preliminary results indicate that particledimension and mask opening size can have a decisive influence on the erosion rate. The mask molding technology we have referred can meet the requirement of etching vias through the depth of 500μmglass substrate. Different etching modes can formdifferenthole structures which is suitable for different MEMS devices, enriching elaborate processing technologyfor glass.

Patterning and Reactive Ion Etching of Diamond Films using Light Coupling Masks

We describe the novel application of light coupling masks (LCM) in the lithographic patterning of fine structures in diamond films. A PDMS mask was used in the exposure of complex patterns of gratings in AZP 1205 resist on a substrate of Al/ diamond. The profiles of these grating patterns were then modified on a localized scale by a process of reflow of the resist. We report on the transfer of the patterns formed in resist by the LCMs into the diamond film using a sputtered Al layer as a mask. The two-stage process comprised etching of the pattern into the Al followed by transfer into the diamond film using CF4/ O2 and CHF3/ O2 gases. The presence of O2 in the CF4/ O2 and CHF3/ O2 gas mixtures produced Al oxides on the surface of the mask. The etch selectivity of the mask was greater in CF4/ O2 than in CHF3/ O2 gases and was only weakly dependent on the concentration of O2 (0-12 sccm).