Chamferless via structures

Patent metadata

Field	Value
Publication number	US-10937694-B2
Application number	US-201916503706-A
Country	US
Kind code	B2
Filing date	Jul 5, 2019
Priority date	Sep 2, 2015
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

Chamferless via structures and methods of manufacture are provided. The method includes: forming at least one non-self-aligned via within at least dielectric material; plugging the at least one non-self-aligned via with material; forming a protective sacrificial mask over the material which plugs the at least one non-self-aligned via, after a recessing process; forming at least one trench within the dielectric material, with the protective sacrificial mask protecting the material during the trench formation; removing the protective sacrificial mask and the material within the at least one non-self-aligned via to form a wiring via; and filling the wiring via and the at least one trench with conductive material.

First claim

What is claimed:

1. A method, comprising:
forming a mask over a via fill material of a non-self-aligned via after recessing the via fill material to below elements formed above a dielectric material;
forming a trench within the dielectric material, with the mask protecting the non-self-aligned via and the via fill material;
removing the mask and the via fill material within the non-self-aligned via to form a wiring via; and
filling the wiring via and the trench with a same conductive material that is continuous and devoid of any intervening material between the wiring via in the non-self-aligned via and the trench,
wherein the trench extends over the wiring via.

2. The method of claim 1 , wherein the via fill material comprises an antireflective coating.

3. The method of claim 1 , wherein the via fill material comprises an optical planar layer.

4. The method of claim 1 , wherein the via fill material comprises a spin on material.

5. The method of claim 1 , wherein the via fill material comprises an ultra low-k dielectric material.

6. The method of claim 1 , wherein the dielectric material is an ultra low-k material.

7. The method of claim 1 , wherein the non-self-aligned via is further formed within an optical planarization layer above the dielectric material.

8. The method of claim 7 , wherein the non-self-aligned via is formed with several etch chemistries.

9. The method of claim 1 , wherein the mask selectively adheres to the via fill material.

10. The method of claim 9 , wherein the mask is Ruthenium.

11. The method of claim 1 , wherein the wiring via has sidewalls at a sidewall angle greater than 85°.

12. The method of claim 1 , wherein the filling the wiring via and the trench with the conductive material comprises forming copper material by an electroplating process.

13. The method of claim 1 , wherein the non-self-aligned via extends between the elements and through a hardmask and etch stop materials to expose an underlying metal material.

14. The method of claim 13 , further comprising removing the elements, the hardmask and the etch stop materials, prior to filling the wiring via.

15. The method of claim 1 , wherein the wiring via has vertical sidewalls with a constant angle in the ultra low-k dielectric material.

16. The method of claim 1 , wherein the trench extends over the top of the wiring via and over an upper surface of the dielectric material surrounding the top of the wiring via, and wherein the conductive material filling the trench covers the upper surface of the conductive material filling the wiring via and covers the upper surface of the dielectric material surrounding the top of the wiring via.

17. The method of claim 1 , further comprising a second wiring via in the dielectric material, wherein the trench extends between the wiring via and the second wiring via, and over an upper surface of conductive material filling the second wiring via.

18. The method of claim 17 , wherein the trench extends over a top of the wiring via and a top of the second wiring via, and over an upper surface of the dielectric material surrounding the top of the wiring via and the top of the second wiring via, and wherein the conductive material filling the trench completely covers the top of the wiring via and the top of the second wiring via, and extends over the upper surface of the dielectric material surrounding the top of the wiring via and the top of the second wiring via.

19. The method of claim 18 further comprising a block material and a metal layer underlying the blocking layer and the conductive material, wherein the dielectric material is directly on and contacting the block material, and wherein the block material is directly on and contacting the metal layer.

20. The method of claim 19 , further comprising a second wiring via in the dielectric material,
wherein the dielectric material is continuous with no etch stop layer at a line/via junction, wherein the dielectric material is an ultra low-k material, wherein the non-self-aligned via is within an optical planarization layer above the dielectric material, wherein the wiring via and the second wiring via have sidewalls at a sidewall angle greater than 85°, wherein the trench extends between the wiring via and the second wiring via, wherein the trench extends over the top of the wiring via and a top of the second wiring via, and over an upper surface of the dielectric material surrounding the tops of the wiring via and the second wiring via, wherein the conductive material filling the trench completely covers the top of the wiring via and the top of the second wiring via, and extends over the upper surface of the dielectric material surrounding the top of the wiring via and the top of the second wiring via, and wherein the metal layer is one of copper and tungsten.

Assignees

• IBM
• Globalfoundries Inc

Inventors

• Lenhardt Mark L
• Mont Frank W
• Peethala Brown C
• Siddiqui Shariq
• Striss Jessica P
• Trickett Douglas M

Classifications

• H10W20/0693

  by forming self-aligned vias · CPC title

• H10P50/73

  using masks for insulating materials · CPC title

• H10W20/087

  involving multiple stacked pre-patterned masks · CPC title

• H10W20/085

  involving intermediate temporary filling with material · CPC title

• H10W20/082

  the openings being tapered via holes · CPC title