US 12,297,099 B2
Process for manufacturing a combined microelectromechanical device and corresponding combined microelectromechanical device
Federico Vercesi, Milan (IT); Luca Seghizzi, Milan (IT); Laura Oggioni, Milan (IT); and Lorenzo Corso, Ruginello (IT)
Assigned to STMICROELECTRONICS S.r.l., Agrate Brianza (IT)
Filed by STMICROELECTRONICS S.r.l., Agrate Brianza (IT)
Filed on May 13, 2022, as Appl. No. 17/744,312.
Claims priority of application No. 102021000013718 (IT), filed on May 26, 2021.
Prior Publication US 2022/0380203 A1, Dec. 1, 2022
Int. Cl. B81B 7/02 (2006.01); B81B 7/00 (2006.01)
CPC B81B 7/02 (2013.01) [B81B 7/0058 (2013.01); B81B 2201/0264 (2013.01); B81B 2203/0127 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A process for manufacturing a combined microelectromechanical device, comprising:
bonding a cap to a die with an adhesive, including forming a first cavity and a second cavity corresponding, respectively, to a first microelectromechanical structure and a second microelectromechanical structure in the die;
forming an access channel through the cap in fluidic communication with the first cavity;
controlling a pressure value inside the first cavity distinct from a pressure value inside the second cavity; and
hermetically closing the first cavity with respect to the access channel,
bonding the cap to the die including:
implementing, prior to forming the access channel, a first bonding phase at a controlled pressure having a first value corresponding to the pressure value inside the second cavity; and
implementing, after forming the access channel, a second bonding phase at a controlled pressure having a second value corresponding to the pressure value inside the first cavity, including the adhesive deforming during the second bonding phase to hermetically seal the first cavity with respect to the access channel.