Structure with conductive plug and method of forming the same

• US 9,576,903 B2
• Filed: 07/16/2015
• Issued: 02/21/2017
• Est. Priority Date: 07/16/2015
• Status: Active Grant

• Current Assignee: Macronix International Co., Ltd.
• Original Assignee: Macronix International Co., Ltd.
• Inventors: Lee, Ching-Hsiung, Tsai, Shih-Chang
• Primary Examiner(s): YUSHINA, GALINA G
• Application Number:
  US14/801,648
• Publication Number:
  US 20170018500A1
• Time in Patent Office: 586 Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/76802 by forming openings in dielectrics
• CPC Class Codes: H01L 21/76816 Aspects relating to the layout of the pattern or to the size of vias or trenches layout of the interconnections per se H01L23/528; CAD of ICs G06F30/00
• CPC Class Codes: H01L 21/76831 in via holes or trenches, e.g. non-conductive sidewall liners
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76879 by selective deposition of conductive material in the vias, e.g. selective C.V.D. on semiconductor material, plating plating on semiconductors in general H01L21/288
• CPC Class Codes: H01L 23/481 Internal lead connections, e.g. via connections, feedthrough structures
• CPC Class Codes: H01L 23/485 consisting of layered constructions comprising conductive layers and insulating layers, e.g. planar contacts H01L23/4821, H01L23/4822, H01L23/4824, H01L23/4825 take precedence; materials H01L23/532, bond pads H01L24/02, bump connectors H01L24/10
• CPC Class Codes: H01L 23/5226 Via connections in a multilevel interconnection structure
• CPC Class Codes: H01L 23/5283 Cross-sectional geometry
• CPC Class Codes: H01L 23/53223 Additional layers associated with aluminium layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 23/53266 Additional layers associated with refractory-metal layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 23/5329 Insulating materials
• CPC Class Codes: H01L 23/53295 Stacked insulating layers

Abstract

Provided is a structure with a conductive plug including a substrate, a first dielectric layer, an etch stop layer, a second dielectric layer, a conductive plug and a liner. The substrate has a conductive region therein. The first dielectric layer, the etch stop layer and the second dielectric layer are sequentially formed on the substrate and have at least one opening therethrough. Besides, the opening has a substantially vertical sidewall. The conductive plug fills in the opening and is electrically connected to the conductive region. The liner surrounds the upper portion of the conductive plug. A method of forming a structure with a conductive plug is further provided.

Claims

1. A structure with a conductive plug, comprising:

a substrate, having a conductive region therein;

a first dielectric layer, an etch stop layer and a second dielectric layer, sequentially disposed on the substrate, wherein a portion of the first dielectric layer and a portion of the etch stop layer are disposed on the conductive region, wherein at least one opening penetrates through the first dielectric layer, the etch stop layer and the second dielectric layer;

a conductive plug, filling in the opening and electrically connected to the conductive region, wherein the conductive plug has a side surface and a bottom surface, and the bottom surface of the conductive plug is in direct contact with the conductive region; and

a liner, disposed on the etch stop layer and surrounding a portion of the side surface of the conductive plug.

2. The structure of claim 1, wherein an aspect ratio of the opening ranges from about 2:

1 to 40;

1.

3. The structure of claim 1, wherein the liner is only disposed between the conductive plug and the second dielectric layer and is in contact with the etch stop layer.

4. The structure of claim 1, wherein the etch stop layer comprises silicon nitride, silicon oxynitride or a combination thereof.

5. The structure of claim 1, wherein the liner comprises polysilicon, amorphous silicon, silicon nitride, silicon oxynitride or a combination thereof.

6. The structure of claim 1, wherein a thickness ratio of the second dielectric layer to the first dielectric layer is about 1:

1 to 20;

1.

7. The structure of claim 1, wherein a thickness ratio of the first dielectric layer to the etch stop layer is about 2:

1 to 10;

1.

8. The structure of claim 1, wherein a thickness ratio of the etch stop layer to the liner is about 5:

3 to 5;

1.

9. The structure of claim 1, wherein the conductive plug comprises:

a barrier layer, disposed on a surface of the opening; and

a metal layer, filling up the opening.

10. The structure of claim 1, wherein the conductive region comprises a doped region, a gate or a wire.