Semiconductor structure and manufacturing method for the same
View Patent ↗The present disclosure provides a micro electro mechanical system (MEMS) structure, including a device substrate having a first region and a second region different from the first region, a capping substrate bonded over the device substrate, a first cavity in the first region and between the device substrate and capping substrate, wherein the first cavity has a first cavity pressure, a second cavity in the second region and between the device substrate and capping substrate, wherein the second cavity has a second cavity pressure lower than the first cavity pressure, an outgassing material, wherein the outgassing material includes a top surface and a sidewall exposed to the first cavity, the outgassing material is free from being in direct contact with the capping substrate, wherein the outgassing material includes a trench, and a passivation layer disposed over the device substrate, and is in direct contact with the outgassing material.
1 . A micro electro mechanical system (MEMS) structure, comprising:
a device substrate having a first region and a second region different from the first region;
a capping substrate bonded over the device substrate;
a first cavity in the first region and between the device substrate and the capping substrate, wherein the first cavity has a first cavity pressure;
a second cavity in the second region and between the device substrate and the capping substrate, wherein the second cavity has a second cavity pressure lower than the first cavity pressure;
an outgassing material comprising a plurality of blocks and a first sidewall between adjacent blocks of the plurality of blocks and exposed to the first cavity, each of the plurality of blocks having a trench defined by a second sidewall; and
a passivation layer disposed over the device substrate, wherein the passivation layer comprises an inner sidewall laterally surrounding an outgassing material, and wherein the first sidewall of the outgassing material extends from a top surface of the outgassing material to a top surface of the passivation layer.
2 . The MEMS structure of claim 1 , wherein the second sidewall connects to a bottom surface of the trench positioned between the top surface of the outgassing material and the top surface of the passivation layer.
3 . The MEMS structure of claim 1 , wherein a bottom surface of the trench is exposed to the first cavity.
4 . The MEMS structure of claim 1 , wherein a depth of the trench being less than or equal to a thickness of the outgassing material.
5 . A micro electro mechanical system (MEMS) structure, comprising:
a device substrate having a first region and a second region different from the first region;
a capping substrate bonded over the device substrate;
a first cavity in the first region and between the device substrate and capping substrate, wherein the first cavity has a first cavity pressure;
a second cavity in the second region and between the device substrate and capping substrate, wherein the second cavity has a second cavity pressure lower than the first cavity pressure;
an outgassing material, wherein the outgassing material comprises a top surface and a first sidewall exposed to the first cavity, wherein the outgassing material comprises a trench, a depth of the trench being less than or equal to a thickness of the outgassing material, and wherein the trench comprises a second sidewall defining the trench; and
a passivation layer disposed over the device substrate, and is in direct contact with the outgassing material, wherein the first sidewall of the outgassing material extends from the top surface of the outgassing material to a top surface of the passivation layer.
6 . The MEMS structure of claim 5 , wherein the outgassing material comprises a material capable of generating substantial outgassing gas after undergoing a temperature for bonding the device substrate and the capping substrate.
7 . The MEMS structure of claim 5 , further comprising a movable component in the first cavity.
8 . The MEMS structure of claim 5 , wherein the top surface of the outgassing material concaves toward the device substrate.
9 . The MEMS structure of claim 5 , wherein the outgassing material comprises oxide.
10 . The MEMS structure of claim 5 , further comprising a recessed portion at the passivation layer, and the outgassing material is disposed in the recessed portion.
11 . The MEMS structure of claim 10 , wherein a bottom of the recessed portion is exposed to the first cavity from the outgassing material.
12 . The MEMS structure of claim 10 , wherein the outgassing material comprises a lower surface between the top surface and a bottom of the recessed portion, the lower surface is exposed to the first cavity.
13 . A micro electro mechanical system (MEMS) structure, comprising:
a device substrate having a first region and a second region adjacent to the first region;
a capping substrate bonded over the device substrate;
a first cavity in the first region and between the device substrate and capping substrate, wherein the first cavity has a first cavity pressure;
a second cavity in the second region and between the device substrate and capping substrate, wherein the second cavity has a second cavity pressure lower than the first cavity pressure;
an outgassing material, wherein the outgassing material comprises a plurality of protrusions protruding away from the device substrate, a top surface and a first sidewall exposed to the first cavity, the outgassing material is free from being in direct contact with the capping substrate; and
a passivation layer disposed over the device substrate, and is in direct contact with the outgassing material, wherein the first sidewall of the outgassing material extends from the top surface of the outgassing material to a top surface of the passivation layer.
14 . The MEMS structure of claim 13 , wherein the passivation layer extends from the first region to the second region.
15 . The MEMS structure of claim 13 , further comprising an outgassing barrier layer in the first cavity.
16 . The MEMS structure of claim 13 , wherein the outgassing material partially covers the passivation layer such that a portion of the passivation layer is exposed to the first cavity.
17 . The MEMS structure of claim 13 , wherein each of the plurality of protrusions comprises a recess depressed from the top surface of the outgassing material.
18 . The MEMS structure of claim 17 , wherein the recess is defined by a second sidewall, the second sidewall being in connection to a bottom surface of the recess positioned between the top surface of the outgassing material and the top surface of the passivation layer.
19 . The MEMS structure of claim 13 , further comprising a metal line covered by the passivation layer.
20 . The MEMS structure of claim 19 , further comprising a rerouting layer connected to the metal line.