Chemically removable Cu CMP slurry abrasive

• US 6,169,034 B1
• Filed: 11/25/1998
• Issued: 01/02/2001
• Est. Priority Date: 11/25/1998
• Status: Expired due to Term

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Yang, Kai, Erb, Darrell M., Avanzino, Steven C., Schonauer, Diana M.
• Primary Examiner(s): Smith, Matthew
• Assistant Examiner(s): Hullinger, Robert A.
• Application Number:
  US09/199,352
• Time in Patent Office: 769 Days
• Field of Search: 438/689, 438/691, 438/692, 438/693, 438/627, 438/687, 134/1.3, 134/6
• US Class Current: 438/693
• CPC Class Codes: C09G 1/02 containing abrasives or grinding agents abrasives as such C09K3/14; polishing of semi-conductors H01L
• CPC Class Codes: C09K 3/1463 Aqueous liquid suspensions
• CPC Class Codes: H01L 21/3212 by chemical mechanical polishing [CMP]

Abstract

Abrasion of Cu metallization during CMP is reduced and residual slurry particulate removal facilitated by employing a CMP slurry containing a dispersion of soft mineral particles having high solubility in dilute acids. Embodiments include CMP Cu metallization with a slurry containing magnesium oxide particles and removing any residual magnesium oxide particles after CMP with an organic acid, such as citric acid or acetic acid, or a dilute inorganic acid, such as hydrochloric, phosphoric, boric or fluoboric acid.

Claims

1. A method of manufacturing a semiconductor device, the method comprising:

depositing a layer of Copper (Cu) or a Cu alloy;

chemical mechanical polishing (CMP) the deposited Cu or Cu alloy with a slurry containing a particulate abrasive material having a hardness less than about Mohs 6; and

chemically removing remaining particulate material after CMP with a dilute acidic solution without buffing or scrubbing.

2. The method according to claim 1, comprising removing dilute particulate material with a dilute solution of citric, acetic, phthalic, tartaric succinic, hydrochloric, phosphoric, boric, or fluoboric acid.

3. The method according to claim according to claim 1, wherein the particulate abrasive material comprises a mineral having a particle size less than 5 μ

m.

4. The method according to claim 3, wherein the mineral has a particle size of about 0.1 μ

m to about 3 μ

m.

5. A method of manufacturing a semiconductor device, the method comprising:

depositing a layer of copper (Cu) or a Cu alloy;

chemical mechanical polishing (CMP) the deposited Cu or Cu alloy with a slurry containing a particulate abrasive material; and

chemically removing remaining particulate material after CMP with a dilute acidic solution of citric, acetic, phthalic, tartaric, succinic, hydrochloric, phosphoric, boric, or fluoboric acid, without buffing or scrubbing;

wherein;

the particulate abrasive material comprises a mineral having a particle size less than 5 μ

m and has a hardness less than about 6 Mohs; and

the mineral comprises a metal oxide.

6. The method according to claim 5, wherein the mineral comprises magnesium oxide.

7. The method according to claim 6, wherein the slurry comprises about 1 wt. % to about 10 wt. % magnesium oxide.

8. The method according to claim 7, wherein the slurry further comprises:

about 0.5 wt. % to about 5 wt. % of ammonium tartrate;

about 0.1 wt. % to about 0.3 wt. % of benzotriazole;

about 1 wt. % to about 5 wt. % hydrogen peroxide; and

about 89.7 wt. % to about 98.4 wt. % of water.

9. The method according to claim 6, comprising:

depositing an interdielectric layer over a substrate;

forming damascene openings in the interdielectric layer;

depositing a barrier layer lining the damascene openings and on the interdielectric layer;

depositing the Cu or Cu alloy on the barrier layer filling the opening; and

CMP.

10. The method according to claim 9, comprising;

depositing a seedlayer on the barrier layer; and

electroplating or electroless plating the Cu or Cu alloy on the seedlayer.

11. A method of manufacturing a semiconductor device, the method comprising:

depositing a layer of copper (Cu) or a Cu alloy;

chemical mechanical polishing (CMP) the deposited Cu or Cu alloy with a slurry containing a particulate abrasive material comprising magnesium oxide; and

removing remaining particulate material after CMP with a dilute acidic solution.

12. The method according to claim 11, wherein the slurry comprises about 1 wt. % to about 10 wt. % magnesium oxide.

13. The method according to claim 12, wherein the slurry further comprises:

about 0.5 wt. % to about 5 wt. % of ammonium tartrate;

about 0.1 wt. % to about 0.3 wt. % of benzotriazole;

about 1 wt. % to about 5 wt. % hydrogen peroxide; and

about 89.7 wt. % to about 98.4 wt. % of water.

14. The method according to claim 11, comprising:

depositing an interdielectric layer over a substrate;

forming damascene openings in the interdielectric layer;

depositing a barrier layer lining the damascene openings and on the interdielectric layer;

depositing the Cu or Cu alloy on the barrier layer filling the opening; and

CMP.

15. The method according to claim 14, comprising:

depositing a seedlayer on the barrier layer; and

electroplating or electroless plating the Cu or Cu alloy on the seedlayer.