IC chip uniform delayering methods
US7504337B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2007 |
| Grant date | Mar 17, 2009 |
| Priority date | — |
| Expiry date | Aug 29, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/24
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods of uniformly delayering an IC chip are disclosed. One embodiment includes: performing an ash on the wafer including an Al layer thereof and etching the Al layer; polishing an edge of the wafer using a slurry including an approximately 30 μm polishing particles; removing the aluminum layer and at least one metal layer by polishing using a slurry including approximately 9 μm diamond polishing particles and a non-abrasive backside of a polishing sheet; removing any remaining metal layers to a first metal layer by polishing using a slurry including approximately 3 μm diamond polishing particles and the non-abrasive backside of a polishing sheet; removing any scratches by polishing using a slurry including approximately 1 μm diamond polishing particles and the non-abrasive backside of a polishing sheet; and removing the first metal layer to a polyconductor layer by polishing using a colloidal slurry including approximately 0.25 μm diamond polishing particles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.