Laser thermal annealing of silicon nitride for increased density and etch selectivity
US6706576B1 · kind B1 · utility
58Cited by
9References
20Claims
0Family size
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Key dates
| Filing date | Mar 14, 2002 |
| Grant date | Mar 16, 2004 |
| Priority date | — |
| Expiry date | Mar 14, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02274
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The density of a deposited silicon nitride layer is increased by laser thermal annealing in N2, thereby increasing etch selectivity with respect to an overlying oxide and, hence, avoiding damage to underlying silicide layers and gates. Embodiments include laser thermal annealing a silicon nitride layer deposited as an etch stop layer, e.g., in fabricating EEPROMs, to increase its density by up to about 8%, thereby increasing its etch selectivity with respect to an overlying BPSG layer to about {fraction (1/12)} to about {fraction (1/14)}.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.