An extreme ultraviolet lithography corrugated plate illumination system

Abstract

The invention provides a corrugated plate illuminating system for extreme ultraviolet lithography. The corrugated plate illuminating system comprises a light source, a collecting lens, a corrugated plate and a relay lens group, wherein the EUV (Extreme Ultraviolet) light transmitted by the light source is collected by the collecting lens to form a parallel beam or an approximate parallel beam with small angle convergence; the parallel beam or the approximate parallel beam sequentially passes through the corrugated plate and the relay lens group and then is radiated to a mask; the corrugated plate serves as a cylindrical reflector array sequentially arranged in the direction perpendicular to the axial direction, and is used for dividing the wide incident beam into a plurality of channels; each channel forms a meridian image and a sagittal image to the light source; the relay lens group comprises a corrected type composite paraboloid collecting lens and a quadric surface reflector, and is used for superposing the meridian image formed by the corrugated plate onto the mask surface, and imaging the sagittal image formed by the corrugated plate to an exit pupil of the illuminating system. The corrugated plate illuminating system disclosed by the invention reduces the quantity of the reflector in the system to increase the efficiency optical energy utilization of the system.

Description

technical field [0001] The invention belongs to the technical field of lithography lighting design, in particular to an extreme ultraviolet lithography corrugated plate lighting system. Background technique [0002] Photolithography is a technology for manufacturing semiconductor devices, which uses optical methods to transfer the circuit pattern on the mask plate to the silicon wafer. A variety of semiconductor devices can be fabricated using photolithography, such as diodes, transistors, and VLSI. A typical lithography exposure system includes illumination system, mask, projection objective lens and silicon wafer. [0003] Extreme ultraviolet lithography (EUVL) is a microelectronic lithography technology that uses EUV radiation with a wavelength of 11-14 nm as the exposure light source. The core component of the projection lithography machine is the projection exposure optical system, and the most important components of the system are the illumination system and the pro...

AI Technical Summary

Problems solved by technology

[0007] The object of the present invention is to overcome the defects of the prior art, in order to solve the problem of low light energy utilization rate of the extreme ultraviolet lithography lighting system, to provide a high light energy utilization rate extreme ultraviolet lithography corrugated plate lighting system, by reducing the reflection in the system The number of mirrors should be increased by grazing incidence as much as possible to improve the light energy utilization rate of the system. The surface shape of the corrugated plate of the uniform light element adopts a cylindrical mirror array, which reduces the difficulty of system processing, and the system has the characteristics of compact structure.

Images