MEMS device and method for manufacturing the same

The MEMS device addresses the issue of isolation joint damage by ensuring the movable part contacts the cavity bottom before the joint, using a two-step etching process to create a recess with a tapered structure, maintaining insulation and preventing joint damage.

JP7893696B2Active Publication Date: 2026-07-22ROHM CO LTD
View PDF 5 Cites 0 Cited by

Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
ROHM CO LTD
Filing Date
2022-09-20
Publication Date
2026-07-22

AI Technical Summary

Technical Problem

Conventional MEMS devices face issues where the trench isolation joint protrudes below the beam structure and contacts the silicon substrate when the beam deforms, leading to damage and reduced insulation performance.

Method used

The MEMS device design ensures that the shortest distance between the movable part and the recess bottom is less than the distance between the movable part and the isolation joint, with a tapered structure preventing contact between the isolation joint and the cavity bottom, and includes a manufacturing process involving two etching steps to form a recess with a smaller depth for the side wall of the second trench.

Benefits of technology

This design prevents damage to the isolation joint and maintains insulation performance by ensuring the isolation joint does not contact the cavity bottom, resulting in a highly reliable MEMS device.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure 0007893696000001
    Figure 0007893696000001
  • Figure 0007893696000002
    Figure 0007893696000002
  • Figure 0007893696000003
    Figure 0007893696000003
Patent Text Reader

Abstract

To provide a MEMS device which prevents contact between an isolation joint and a bottom of a cavity while maintaining insulation of the isolation joint.SOLUTION: A MEMS device with a movable portion: a substrate; a recess provided in the substrate; a movable portion supported in the recess in a hollow state; and an isolation joint inserted into a predetermined position of the movable portion for electrically insulating the movable portion on both sides of the movable portion. The shortest distance (fg1) between a bottom of the recess and the movable portion is smaller than distance (fg2) between the bottom of the recess and the isolation joint (fg1<fg2). A depth (s2) of the movable portion adjacent to the isolation joint is less than a depth (t) of the isolation joint. The movable portion includes a portion having a depth (mh) greater than the depth (t) of the isolation joint.SELECTED DRAWING: Figure 2
Need to check novelty before this filing date? Find Prior Art