System to reduce heat-induced distortion of photomasks during lithography
US6521901B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1999 |
| Grant date | Feb 18, 2003 |
| Priority date | — |
| Expiry date | Nov 30, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31794
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
The present invention relates generally to methods, apparatuses and materials to reduce or minimize the heating of a substrate (and associated distortions of the photomask) caused by electron-beam energy deposited in the substrate during patterning. The present invention provides useful materials and methods for reducing such reflection or re-radiation effects, leading to temperature stability of the substrate, reduced thermal distortion and the possibility of increased patterning accuracy. The infrared absorbing materials of the present invention also possess sufficient electrical conductivity to dissipate scattered electrons residing on the material, and sufficient thermal conductivity to dissipate heat rapidly and not result in local heating or significant temperature rise of the absorber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.