US 2006/0068334 A1 · Phase-shifting optical maskless lithography enabling asics at the 65 and 45 NM nodes

Abstract

Phase stepped and paired piston SLM configurations are described, with attention to rasterization and image stability. In contrast to attenuated phase-shift reticle performance of simple titling mirror SLMs, these configuration have phase shifting capabilities emulating a hard phase shift reticle and beyond. To use a straight-forward rasterization architecture where individual pixels are determined by the local pattern data, the SLM is operated so that the complex amplitude created by a mirror or mirror pair is confined to the real axis. The tilting phase-step mirror SLM gives a new set of rules for lithography: no penalty for phase shift over binary, no penalty for OPC verses non-OPC pattern, seamless pattern decompositions, optimal tones for each pattern, etc. This gives performance and flexibility never seen before.

Claims24

Dependent claims

A method of producing a complex valued amplitude signal by relaying radiation from paired reflective piston elements in a Spatial Light Modulator (SLM), the method including:

pairing reflective piston elements having a reference difference in surface height substantially corresponding to a positive natural number multiple (1, 2, 3 . . . ) of one quarter wavelength of an electromagnetic radiation used to illuminate the paired piston elements;
transmitting one or more control signals to the paired piston elements to actuate the paired piston elements to produce a complex valued amplitude signal;
and
relaying the electromagnetic radiation from a multitude of the paired piston elements toward and image plane.

1 more element

Dependencies are inferred from the claim text.

Phase-shifting optical maskless lithography enabling asics at the 65 and 45 NM nodes

Life of this patent

Phase-shifting optical maskless lithography enabling asics at the 65 and 45 NM nodes

Life of this patent

Abstract

Claims24