A process for manufacturing a microelectromechanical device with a mobile structure, in particular a micromirror

Abstract

The application discloses a process for manufacturing a microelectromechanical device with a mobile structure, in particular a micromirror. The manufacturing process comprising the steps of: forming abottom semiconductor region including a main sub-region, which extends through a bottom dielectric region that coats a semiconductor wafer, and a secondary sub-region, which coats the bottom dielectric region and surrounds the main sub-region; forming a first top cavity and a second top cavity through the wafer, delimiting a fixed body and a patterned structure that includes a central portion, which contacts the main sub-region, and deformable portions, in contact with the bottom dielectric region; forming a bottom cavity through the bottom semiconductor region, as far as the bottom dielectric region, the bottom cavity laterally delimiting a stiffening region that includes the main sub-region and leaving exposed parts of the bottom dielectric region that contact the deformable portions and parts of the bottom dielectric region that delimit the first and second top cavities; and selectively removing the parts left exposed by the bottom cavity.

Description

[0001] Statement of priority [0002] This application claims priority to Italian Patent Application No. 102018000008533, filed September 12, 2018, the contents of which are hereby incorporated by reference in their entirety to the fullest extent permitted by law. technical field [0003] The present disclosure relates to a method for manufacturing microelectromechanical devices, in particular micromirrors, with moving structures. Background technique [0004] Known in the art are MEMS (Micro Electro Mechanical Systems) devices with mirror structures obtained using semiconductor technology. [0005] The MEMS devices described above are used, for example, in portable devices, such as portable computers, laptops, notebooks (including ultra-thin notebooks), PDAs, tablet computers, smartphones, for optical applications, in particular for light generated by light sources The radiation beam is directed in a desired scan pattern or modality. [0006] Due to their small size, the...

AI Technical Summary

Problems solved by technology

Such selective removal of semiconductor material cannot be obtained by timed etching, as this would lead to excessive variability between different MEMS devices formed starting from wafers of semiconductor material as described above

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