MEMS structure for a MEMS device, MEMS device, and method for manufacturing the MEMS structure

Abstract

The present disclosure relates to a MEMS structure 100 for a MEMS device 1000, in particular a MEMS mirror device, comprising: a functional element 1 which is designed to be oscillatingly movable along and / or about at least two oscillation axes X, Y, and spring sections 3a - 3d which hold the functional element 1 oscillatingly movable along and / or about the at least two oscillation axes, wherein at least a portion of the spring sections 3a - 3d is spaced from the functional element 1 in the direction of a normal vector of a substrate plane and the spring sections 3a - 3d of the portion of the spring sections 3a - 3d are designed to be axially symmetrical to at least one of the oscillation axes X, Y.

Claims

[1] MEMS structure (100) for a MEMS device (1000), in particular a MEMS mirror device (1000), comprising: - a functional element (1) which is designed to be movable in an oscillating manner along and / or around at least two oscillation axes (X, Y), and - spring sections (3a - 3d) which hold the functional element (1) so as to be oscillatingly movable along and / or about the at least two oscillation axes, wherein at least some of the spring sections (3a - 3d) are spaced apart from the functional element (1) in the direction of a normal vector of a substrate plane and the spring sections (3a - 3d) of the part of the spring sections (3a - 3d) are axially symmetrical to at least one of the oscillation axes (X, Y). [2] MEMS structure (100) according to claim 1, wherein the at least one part of the spring sections (3a - 3d) at least partially overlaps with the functional element (1) in a direction perpendicular to the normal vector of the substrate plane. [3] MEMS structure (100) according to claim 1 or 2, wherein the functional element (1) has at least one coupling section (2), in particular at least two coupling sections (2), by means of which the functional element (1) is mechanically connected to the spring sections (3a - 3d). [4] MEMS structure (100) according to claim 4, wherein the at least one coupling section (2) or the at least two coupling sections (2) are connected to the functional element (1) on the side of the functional element (1) which faces the spring sections (3a - 3d). [5] MEMS structure (100) according to claim 3 or 4, wherein the at least one coupling section (2) or at least one of the at least two coupling sections (2) comprises at least two support sections (2a) connected to the functional element (1) and a beam section (2b) connecting the at least two support sections (2a) to one another and connected to at least one spring section (3a - 3d). [6] MEMS structure (100) according to one of the preceding claims, wherein the spring sections (3a - 3d) are formed in pairs for the oscillation of the functional element (1) in the corresponding dimension. [7] MEMS structure (100) according to claim 6, wherein each pair of spring sections (3a - 3d) has a connecting section (3v) by means of which the two spring sections (3a - 3d) of the respective pair are connected to each other, and the connecting portion (3v) of a first pair of spring portions (3a, 3b) is also the connecting portion (3v) of a second pair of spring portions (3c, 3d). [8] MEMS structure (100) according to claim 7, wherein each of the spring sections (3a, 3b) of the first pair is connected to one of the two coupling sections (2) at an end opposite the connecting section (3v), and each of the spring portions (3c, 3d) of the second pair has, at an end opposite the connecting portion (3v), an anchor portion (4a) adapted to be connected to an external structure (10). [9] MEMS structure (100) according to claim 7 or 8, wherein the second pair of spring sections (3c, 3d) is designed to protrude in the longitudinal direction (L) of the second pair of spring sections (3c, 3d) relative to the functional element (1), or the functional element (1) has an overhang (U) in the longitudinal direction (L) of the second pair of spring sections (3c, 3d) relative to the second pair of spring sections (3c, 3d), advantageously an overhang (U) of 10 - 50% of the length (L) of the second pair of spring sections (3c, 3d), particularly advantageously an overhang (U) of 25 - 35% of the length (L) of the second pair of spring sections (3c, 3d), or the second pair of spring sections (3c, 3d) terminates with the functional element (1) in the longitudinal direction (L) of the second pair of spring sections (3c, 3d), so that neither the functional element (1) has an overhang (U) in the longitudinal direction (L) of the second pair of spring sections (3c, 3d) relative to the second pair of spring sections (3c, 3d), nor does the second pair of spring sections (3c, 3d) protrude relative to the functional element (1) in the longitudinal direction (L) of the second pair of spring sections (3c, 3d). [10] MEMS structure (100) according to one of claims 3 to 9, wherein the functional element (1) has a functional section (1a) and a frame section (1c) surrounding the functional section (1a), and the frame section (1c) of the functional element (1) has at least one coupling section (2), by means of which the functional element (1) is mechanically connected to the spring sections (3a - 3d). [11] MEMS structure (100) according to claim 10, wherein the functional element (1) further comprises at least two holding sections (1b) formed between the functional section (1a) and the frame section (1c) and mechanically connecting the functional section (1a) to the frame section (1c). [12] MEMS structure (100) according to one of claims 3 to 9, wherein the functional element (1) further comprises at least one holding section (1b) which is formed between a functional section (1a) and at least one coupling section (2) and mechanically connects the functional section (1a) to the respective coupling section (2). [13] MEMS structure (100) according to claim 11 or 12, wherein the at least one holding section (1b) or the at least two holding sections (1b) are further designed as resilient holding sections (1b), in particular as torsion- and / or bending-resilient holding sections (1b). [14] MEMS structure (100) according to one of the preceding claims, wherein each of the spring sections (3a - 3d) which is spaced from the functional element (1) in the direction of the normal vector of the substrate plane is formed from two parallel spring subsections (3aa - 3db). [15] MEMS structure (100) according to claims 7 and 14, wherein a first spring section (3aa) of a first spring section (3a) of the first pair of spring sections (3a, 3b) has a connecting section with a first spring section (3da) of a second spring section (3d) of the second pair of spring sections (3c, 3d), a second spring section (3db) of the second spring section (3d) of the second pair of spring sections (3c, 3d) has a connecting section with a second spring section (3bb) of a second spring section (3b) of the first pair of spring sections (3a, 3b), a first spring section (3ba) of the second spring section (3b) of the first pair of spring sections (3a, 3b) has a connecting section with a first spring section (3ca) of the first spring section (3c) of the second pair of spring sections (3c, 3d), and a second spring section (3cb) of the first spring section (3c) of the second pair of spring sections (3c, 3d) has a connecting section with a second spring section (3ab) of the first spring section (3a) of the first pair of spring sections (3a, 3b). [16] MEMS structure (100) according to claim 15, wherein each of the spring portions (3ca, 3cb, 3da, 3db) of the second pair has, at an end opposite to the connecting portion, an anchor portion (3k1, 3k2) adapted to be connected to an external structure (10). [17] MEMS structure (100) according to claim 16, wherein between the respective anchor section (3k1, 3k2) and the respective spring part section (3ca, 3cb, 3da, 3db) of the second pair, a lever section (3Lca, 3Lcb, 3Lda, 3Ldb) is further formed, which is configured to excite an oscillation of the functional element (1). [18] MEMS structure (100) according to claim 17, wherein the lever sections (3Lca, 3Lcb, 3Lda, 3Ldb) are arcuate or partially circular. [19] MEMS structure (100) according to one of the preceding claims, further comprising: at least one actuator (8a, 8b) which is provided on at least one of the spring sections (3a - 3d) which are spaced from the functional element (1) in the direction of the normal vector of the substrate plane, or on at least one lever section (3Lca, 3Lcb, 3Lda, 3Ldb). [20] MEMS structure (100) according to claim 19, wherein the at least one actuator (8a, 8b) is provided on the side of the at least one spring section (3a - 3d) facing away from the functional element (1), or the at least one actuator (8a, 8b) is provided on the side of the at least one lever section (3Lca, 3Lcb, 3Lda, 3Ldb) which faces away from the functional element (1). [21] MEMS structure (100) according to one of the preceding claims, wherein the functional element (1) has a functional section (1a) with a functional surface (1d) formed by a mirror surface (1d) or by a mirror element (1d) provided on the functional section (1a). [22] MEMS device (1000), in particular a MEMS mirror device, comprising: - a MEMS structure (100) according to one of the preceding claims, - an outer structure (10) to which the MEMS structure (100) is connected, and - a transparent element (7), wherein the outer structure (10) and the transparent element (7) are adapted to vacuum pack the MEMS structure (100) within the MEMS device (1000). [23] A method for manufacturing a MEMS structure (100) according to any one of claims 1 to 21, comprising: - Providing (S101) a base layer (L1) with a first stack (L2) comprising a semiconductor layer (L2a) and an insulator layer (L2b), wherein the insulator layer (L2b) of the first stack (L2) is connected to the base layer (L1), - Structuring (S102) the semiconductor layer (L2a) of the first stack (L2) to form the at least two coupling sections (2), - Providing (S103) a second stack (L3) on the structured semiconductor layer (L2a) of the first stack (L2), wherein the second stack (L3) has a semiconductor layer (L3a) and an insulator layer (L3b), and the insulator layer (L3b) of the second stack (L3) is connected at least to the at least two structured coupling sections (2), - Structuring (S104) the semiconductor layer (L3a) of the second stack (L3) to form the spring sections (3a - 3d), which are spaced from the functional element (1) in the direction of the normal vector of the substrate plane and are axially symmetrical to the at least one of the oscillation axes (X, Y), and the respective anchor sections (4a, 3k1, 3k2), - Structuring (S105) the base layer (L1) to form the functional element (1), and - partially removing (S106) the insulator layer (L2b) of the first stack (L2) and / or the insulator layer (L3b) of the second stack (L3).

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