Method for reducing leaching in metal-coated MEMS
AssigneeNetwork Photonics, Inc.
InventorsBevan Staple, David Miller, Lilac Muller
Life of this patent
Estimating the term…
Abstract
A method is provided for preventing dopant leaching from a doped structural film during fabrication of a microelectromechanical system. A microstructure that includes the doped structural film, sacrificial material, and metallic material is produced with a combination of deposition, patterning, and etching techniques. The sacrificial material is dissolved with a release solution that has a substance destructive to the sacrificial material. This substance also acts as an electrolyte, forming a galvanic cell with the doped structural film and metallic material acting as electrodes. The effects of the galvanic cell are suppressed by including a nonionic detergent mixed in the release solution.
Claims34
A method for preventing dopant leaching from a doped structural film during fabrication of a microelectromechanical system, the method comprising:
- producing a microstructure that includes the doped structural film, sacrificial material, and metallic material by a combination of techniques selected from the group consisting of deposition, patterning, and etching;
- dissolving the sacrificial material with a release solution, the release solution comprising a substance destructive to the sacrificial material and acting as an electrolyte to form a galvanic cell with the doped structural film and metallic material acting as electrodes;
- and
- suppressing effects of the galvanic cell by including a nonionic detergent mixed in the release solution.
A method for preventing dopant leaching from a doped polysilicon structural film during fabrication of a surface micromachined mirror array having a plurality of moveable reflective surfaces for use in a wavelength router, the method comprising:
- producing a mirror microstructure that includes the doped polysilicon, sacrificial silicon oxide material, and gold by a combination of techniques selected from the group consisting of deposition, patterning, and etching;
- dissolving the silicon oxide material with a release solution, the release solution comprising HF and acting as an electrolyte forming a galvanic cell with the doped polysilicon structural film and gold acting as electrodes;
- and
- suppressing effects of the galvanic cell by including a nonionic detergent mixed in the release solution.
A method for fabricating a routing mechanism for use in a wavelength router of the type configured to receive, at an input port, light having a plurality of spectral bands and to direct subsets of the spectral bands to respective ones of a plurality of output ports by providing optical paths in a free-space optical train disposed between the input ports and the output ports and by providing the routing mechanism to direct a given spectral band to different output ports depending on a state of a dynamically configurable routing unit in the routing mechanism, the method comprising:
- forming a plurality of such dynamically configurable routing units on a doped structural film with sacrificial material and metallic material by a combination of techniques selected from the group consisting of deposition, patterning, and etching;
- dissolving the sacrificial material with a release solution, the release solution comprising a substance destructive to the sacrificial material and acting as an electrolyte forming a galvanic cell with the doped structural film and metallic material acting as electrodes;
- and
- suppressing the effects of the galvanic cell by including a nonionic detergent mixed in the release solution,
- whereby dopant leaching from the doped structural film due to the effects of the galvanic cell is suppressed.
Dependencies are inferred from the claim text.