US Patent No. 10,988,372

MEMS DEVICE WITH REDUCED ELECTRIC CHARGE, CAVITY VOLUME AND STICTION


Patent No. 10,988,372
Issue Date April 27, 2021
Title Mems Device With Reduced Electric Charge, Cavity Volume And Stiction
Inventorship Dongyang Kang, San Jose, CA (US)
Assignee InvenSense, Inc., San Jose, CA (US)

Claim of US Patent No. 10,988,372

1. A method comprising:forming a first mask on a first portion of a first surface of a substrate;
forming a second mask on the first mask and further forming the second mask on a second portion of the first surface of the substrate;
etching an first exposed portion of the first surface of the substrate;
removing the second mask;
etching a second exposed portion of the first surface of the substrate;
removing the first mask;
forming an oxide layer on the first surface of the substrate;
forming a third mask on the oxide layer except for a portion of the oxide layer corresponding to bumpstop features;
removing the portion of the oxide layer corresponding to the bump stop features;
etching third exposed portion of the first surface of the substrate; and
removing the third mask.