US 11,851,324 B2
Method for sealing entries in a MEMS element
Christoph Hermes, Kirchentellinsfurt (DE); Hans Artmann, Boeblingen-Dagersheim (DE); Heribert Weber, Nuertingen (DE); Peter Schmollngruber, Aidlingen (DE); Thomas Friedrich, Moessingen-Oeschingen (DE); Tobias Joachim Menold, Weil der Stadt (DE); and Mawuli Ametowobla, Stuttgart (DE)
Assigned to ROBERT BOSCH GMBH, Stuttgart (DE)
Appl. No. 17/291,251
Filed by Robert Bosch GmbH, Stuttgart (DE)
PCT Filed Dec. 13, 2019, PCT No. PCT/EP2019/085117
§ 371(c)(1), (2) Date May 4, 2021,
PCT Pub. No. WO2020/126922, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 102018222749.7 (DE), filed on Dec. 21, 2018.
Prior Publication US 2022/0002147 A1, Jan. 6, 2022
Int. Cl. B81C 1/00 (2006.01)
CPC B81C 1/00047 (2013.01) [B81B 2201/0257 (2013.01); B81B 2201/0264 (2013.01); B81B 2203/0315 (2013.01); B81C 2203/0145 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for sealing entries in a MEMS element, comprising the following steps:
providing a functional layer having a functional region;
producing a cavity underneath the functional region of the functional layer using a first entry outside of the functional region of the functional layer, at least a part of the first entry is a trench that extends circumferentially around at least a part of the cavity so that the first entry is arranged at multiple sides of the cavity;
sealing the first entry after the production of the cavity;
subsequent to the sealing of the first entry, producing a second entry to the cavity, outside of the functional region of the functional layer, wherein the second entry is located laterally to a single position of the cavity without extending circumferentially around the cavity, so that the second entry is entirely located laterally to only a single side of the cavity;
melting sealing material in a region of the second entry; and
cooling off the melted sealing material to seal the second entry.