公开(公告)号：EP3839603A1

公开(公告)日：2021-06-23

申请号：EP20215784.8

申请日：2020-12-18

Applicant: STMicroelectronics S.r.l.

Inventor： SEGHIZZI, Luca ,  BONI, Nicolò ,  OGGIONI, Laura ,  CARMINATI, Roberto ,  CARMINATI, Marta

IPC: G02B26/08 ,  B81B3/00 ,  B81C1/00

Abstract: For manufacturing an optical microelectromechanical device (70), a first wafer (90) of semiconductor material having a first surface (100A) and a second surface (100B) is machined to form a suspended mirror structure (86), a fixed structure (74) surrounding the suspended mirror structure (86), elastic supporting elements (84A-84D) which extend between the fixed structure and the suspended mirror structure, and an actuation structure (83), coupled to the suspended mirror structure. A work wafer (10') is machined separately to form a second wafer (15) having a chamber (104) delimited by a bottom wall having a through opening (103). The second wafer is bonded to the first surface (100A) of the first wafer (90) in such a way that the chamber (104) overlies the actuation structure (83) and the through opening (103) is aligned to the suspended mirror structure (86). Furthermore, a third wafer (98) is bonded to the second surface (100B) of the first wafer to form a composite wafer device (112). The composite wafer device (112) is then diced to form an optical microelectromechanical device (70).

公开(公告)号：EP4293409A1

公开(公告)日：2023-12-20

申请号：EP23177206.2

申请日：2023-06-05

Applicant: STMicroelectronics S.r.l.

Inventor： BONI, Nicolò ,  CARMINATI, Roberto ,  MERLI, Massimiliano

IPC: G02B26/08 ,  B81B1/00 ,  H10N30/00

Abstract: A microelectromechanical mirror device (3) has a first mirror tiltable structure (3a, 10) provided in a first die (11) of semiconductor material having a main extension in a horizontal plane (xy) defined by a first (x) and by a second (y) horizontal axes. The first mirror tiltable structure (3a, 10) has: a fixed structure (14) defining a frame (14') which delimits a cavity (13); a tiltable element (12) carrying a reflecting region (12'), elastically suspended above the cavity (13) and having a first (A) and a second (B) median axes of symmetry, elastically coupled to the frame (14') by a first (15a) and a second (15b) coupling structures, on opposite sides of the second axis (B); and a driving structure (20), coupled to the tiltable element (12) to cause it to rotate around the first axis (A) with a resonance movement. The first mirror tiltable structure (3a, 10) is asymmetrical with respect to the second axis (B) and has, along the first horizontal axis (x): a first extension dimension (d1), on a first side of the second axis (B); and a second extension dimension (d2), greater than the first extension dimension (d1), on a second side of the second axis (B), opposite to the first side.

公开(公告)号：EP4092475A1

公开(公告)日：2022-11-23

申请号：EP22171657.4

申请日：2022-05-04

Applicant: STMicroelectronics S.r.l.

Inventor： BONI, Nicolò ,  MENDICINO, Gianluca ,  DUQI, Enri ,  CARMINATI, Roberto ,  MERLI, Massimiliano

IPC: G02B26/08

Abstract: A microelectromechanical mirror device (1; 100) has, in a die (1') of semiconductor material: a fixed structure (4) defining a cavity (3); a tiltable structure (2) carrying a reflecting region (2'), elastically suspended above the cavity; at least a first pair of driving arms (12a, 12b), coupled to the tiltable structure and carrying respective piezoelectric material regions (13) which may be biased to cause a rotation thereof around at least one rotation axis; elastic suspension elements (6a, 6b), which couple the tiltable structure elastically to the fixed structure, being stiff with respect to movements out of the horizontal plane and yielding with respect to torsion; and a piezoresistive sensor (20), configured to provide a detection signal (S r ) indicative of the rotation of the tiltable structure. At least one test structure (30, 30') is integrated in the die to provide a calibration signal (S c ) indicative of a sensitivity variation of the piezoresistive sensor (20), in order to calibrate the detection signal (S r ).

公开(公告)号：EP4083679A1

公开(公告)日：2022-11-02

申请号：EP22170130.3

申请日：2022-04-26

Applicant: STMicroelectronics S.r.l.

Inventor： CARMINATI, Roberto ,  BONI, Nicolò ,  MARTINI, Irene ,  MERLI, Massimiliano ,  OGGIONI, Laura

IPC: G02B26/08 ,  B81C1/00

Abstract: A process for manufacturing a microelectromechanical mirror device includes: in a semiconductor wafer (50), defining a support frame (2), a plate (5) connected to the support frame (2) so as to be orientable around at least one rotation axis (X) and cantilever structures (9) extending from the support frame (2) and coupled to the plate (5) so that bending of the cantilever structures (9) causes rotations of the plate (5) around the at least one rotation axis (X); forming piezoelectric actuators (10) on the cantilever structures (9); forming pads (12) on the support frame (2); and forming spacer structures (25) protruding from the support frame (2) more than both the pads (12) and the stacks of layers (15, 16, 17, 20, 21, 22) forming the piezoelectric actuators (10).

公开(公告)号：EP3984944A1

公开(公告)日：2022-04-20

申请号：EP21202712.2

申请日：2021-10-14

Applicant: STMicroelectronics S.r.l.

Inventor： BONI, Nicolò ,  VINCIGUERRA, Lorenzo ,  CARMINATI, Roberto ,  MERLI, Massimiliano

IPC: B81B3/00 ,  G02B26/08

Abstract: The MEMS device (1) is formed by a body (5) of semiconductor material, which defines a support structure (10); by a pass-through cavity (15) in the body, which is surrounded by the support structure; by a movable structure (20) suspended in the pass-through cavity; by an elastic structure (25), which extends in the pass-through cavity between the support structure (10) and the movable structure (20). The elastic structure has a first portion (25A) and a second portion (25B) and is subject, in use, to mechanical stress. The MEMS device is further formed by a metal region (45), which extends on the first portion (25A) of the elastic structure (25), and by a buried cavity (30) in the elastic structure, wherein the buried cavity extends between the first and the second portions of the elastic structure.

公开(公告)号：EP3854751A1

公开(公告)日：2021-07-28

申请号：EP21152454.1

申请日：2021-01-20

Applicant: STMicroelectronics S.r.l.

Inventor： DUQI, Enri ,  BONI, Nicolò ,  BALDO, Lorenzo ,  MERLI, Massimiliano ,  CARMINATI, Roberto

IPC: B81C1/00 ,  G02B26/08

Abstract: A method of processing a wafer (100) for manufacturing an oscillating structure (30), comprising the steps of: forming torsional elastic elements (56, 58); forming a mobile element (54, 60) connected to the torsional elastic elements; processing the first side of the wafer to form a mechanical reinforcement structure (112); and processing the second side of said wafer by steps of chemical etching, deposition of metal material, and/or deposition of piezoelectric material. Processing of the first side of the wafer is carried out prior to processing of the second side of the wafer so as not to damage possible sensitive structures formed on the first side of the wafer.

公开(公告)号：EP3839602A1

公开(公告)日：2021-06-23

申请号：EP20212233.9

申请日：2020-12-07

Applicant: STMicroelectronics S.r.l.

Inventor： BONI, Nicolò ,  CARMINATI, Roberto ,  MERLI, Massimiliano

IPC: G02B26/08 ,  B81B3/00

Abstract: A microelectromechanical mirror device (200) has: a fixed structure (24) defining a cavity (23); a tiltable structure (22) carrying a reflecting surface (22'), elastically suspended above the cavity (23) and having a main extension in a horizontal plane (xy); elastic elements (26a-26b, 34a-34d) coupled to the tiltable structure (22); at least one first pair of driving arms (32a, 32b), which carry respective regions of piezoelectric material (33), that can be biased to cause rotation of the tiltable structure (22) about at least one first axis of rotation (X) parallel to a first horizontal axis (x) of the horizontal plane (xy), are elastically coupled to the tiltable structure on opposite sides of the first axis of rotation (X) and are interposed between the tiltable structure (22) and the fixed structure (24). The driving arms (32a, 32b) have, along an orthogonal axis (z) transverse to the horizontal plane (xy), a thickness smaller than that of at least some of the elastic elements (26a-26b, 34a-34d) coupled to the tiltable structure (22).