Hard abrasive particle-free polishing of hard materials

US11078380B2 · kind B2 · utility

Assignees

• ENTEGRIS, INC. · US
• University of Florida Research Foundation, INC. · US

Inventors

• Rajiv Singh · Natick, US
• Arul Chakkaravarthi Arjunan · Gainesville, US
• Deepika Singh · Gainesville, US
• Chaitanya Ginde · Gainesville, US
• Puneet Narendra JAWALI · Gainesville, US

Key dates

• Filing date: Jul 10, 2017
• Grant date: Aug 3, 2021
• Expiry date: Jul 10, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/3212
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A method of CMP includes providing a slurry solution including ≥1 per-compound oxidizer in a concentration between 0.01 M and 2 M with a pH from 2 to 5 or 8 to 11, and ≥1 buffering agent which provides a buffering ratio ≥1.5 that compares an amount of a strong acid needed to reduce the pH from 9.0 to 3.0 as compared to an amount of strong acid to change the pH from 9.0 to 3.0 without the buffering agent. The slurry solution is exclusive any hard slurry particles or has only soft slurry particles that have throughout a Vickers hardness <300 Kg/mm2 or Mohs Hardness <4. The slurry solution is dispensed on a hard surface having a Vickers hardness >1,000 kg/mm2 is pressed by a polishing pad with the slurry solution in between while rotating the polishing pad relative to the hard surface.