Maskless lithography
US5870176A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1997 |
| Grant date | Feb 9, 1999 |
| Priority date | — |
| Expiry date | Jun 18, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/904
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides a method for maskless lithography. A plurality of individually addressable and rotatable micromirrors together comprise a two-dimensional array of micromirrors. Each micromirror in the two-dimensional array can be envisioned as an individually addressable element in the picture that comprises the circuit pattern desired. As each micromirror is addressed it rotates so as to reflect light from a light source onto a portion of the photoresist coated wafer thereby forming a pixel within the circuit pattern. By electronically addressing a two-dimensional array of these micromirrors in the proper sequence a circuit pattern that is comprised of these individual pixels can be constructed on a microchip. The reflecting surface of the micromirror is configured in such a way as to overcome coherence and diffraction effects in order to produce circuit elements having straight sides.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.