US 12,557,306 B2Granted

Convex shape trench in RDL for stress relaxation

AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.

InventorsChia-Nan Lin, Yen-Cheng Lin, Jiann-Horng Lin

Life of this patent

Estimating the term…

Loading patent…

Abstract

A method includes: providing a passivation layer with an embedded MIM capacitor; forming a redistribution layer (RDL) above the passivation layer; and forming an opening in the RDL above the MIM capacitor, wherein the opening separates the RDL into first and second RDL structures, wherein each of the first and second RDL structures has a convex-shaped profile on a sidewall that defines the opening that separates the first RDL structure from the second RDL structure, and wherein the convex-shaped profile on the sidewalls resists stress migration from the RDL to the MIM capacitor to resist stress migration induced cracks forming in the MIM capacitor. The forming an opening includes: removing a portion of the RDL to a first depth using first etching operations; and removing a portion of the RDL to a second depth by laterally etching sidewalls of the first and second RDL structures.

Claims20

Dependent claims

A method comprising:

providing a first passivation layer over a substrate with a metal-insulator-metal (MIM) capacitor embedded in the first passivation layer;
forming a redistribution layer (RDL) above the first passivation layer;
and
forming an opening in the RDL above a portion of the MIM capacitor, wherein the opening separates the RDL into a first RDL structure and a second RDL structure, wherein each of the first RDL structure and the second RDL structure has a convex-shaped profile on a sidewall that defines the opening that separates the first RDL structure from the second RDL structure, forming the opening comprising:
removing a portion of the RDL above the portion of the MIM capacitor to a first depth using first etching operations;
and
removing a portion of the RDL above the portion of the MIM capacitor to a second depth to a top level of the first passivation layer by performing second etching operations that include lateral etching of sidewalls of the first RDL structure and the second RDL structure below the first depth to the second depth, wherein the lateral etching forms the convex-shaped profile on the sidewalls.

4 more elements

A method comprising:

providing a substrate having an interconnect structure in a dielectric layer over the substrate and having a first passivation layer over the dielectric layer, the first passivation layer having a first sublayer, a second sublayer over the first sublayer, and a metal-insulator-metal (MIM) capacitor formed between the first sublayer and the second sublayer;
forming a redistribution layer (RDL) above the first passivation layer and in an opening in the first passivation layer above a top metal structure in the interconnect structure to connect to the top metal structure;
and
forming an opening in the RDL above a portion of the MIM capacitor, wherein the opening separates the RDL into a first RDL structure that is not connected to the top metal structure and a second RDL structure that includes the RDL that connects to the top metal structure, wherein each of the first RDL structure and the second RDL structure has a convex-shaped profile on a sidewall that defines the opening that separates the first RDL structure from the second RDL structure, wherein forming the opening comprises:
forming a patterned photoresist (PR) layer that defines an opening above the portion of the MIM capacitor;
removing a portion of the RDL under the opening in the patterned PR layer to a first depth using first etching operations;
removing a portion of the RDL under the opening in the patterned PR layer to a second depth at a top of the first passivation layer by performing second etching operations that include lateral etching of sidewalls of the first RDL structure and the second RDL structure below the first depth to the second depth, the lateral etching forming the convex-shaped profile on the sidewalls;
and
removing the patterned PR layer.

6 more elements

A method comprising:

providing a substrate having an interconnect structure in a dielectric layer over the substrate and having a first passivation layer over the dielectric layer, the first passivation layer having a first sublayer, a second sublayer over the first sublayer, and a metal-insulator-metal (MIM) capacitor formed between the first sublayer and the second sublayer;
forming a redistribution layer (RDL) above the first passivation layer;
forming an opening in the RDL above a portion of the MIM capacitor, wherein the opening separates the RDL into a first RDL structure and a second RDL structure, wherein each of the first RDL structure and the second RDL structure has a convex-shaped profile on a sidewall that defines the opening that separates the first RDL structure from the second RDL structure, wherein forming the opening comprises:
vertical etching a portion of the RDL above the portion of the MIM capacitor to a first depth using anisotropic vertical etching operations;
and
laterally etching sidewalls of the first RDL structure and the second RDL structure below the first depth to a second depth at a top level of the first passivation layer thereby forming the convex-shaped profile on the sidewalls;
and
filling the opening between the first RDL structure and the second RDL structure with a second dielectric layer.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 18/163,995Filed 3 Feb 2023 · us provisional application
Priority: 23 Dec 2022
Published: US 2024/0213190 A127 Jun 2024
Granted: 17 Feb 2026
Term ends: Not estimatedThe source records don’t support an estimate.

Classification17 codes

H10D 1/692
Capacitors having no potential barriers: electrodes
H10W 10/0142
Using trench refilling with dielectric materials, e.g. shallow trench isolations: the dielectric materials being chemical transformed from…
H10W 10/17
Isolation regions comprising dielectric materials: formed using trench refilling with dielectric materials, e.g. shallow trench isolations
H10W 20/067
Of conductive parts of the interconnections: by modifying the pattern of conductive parts