Method of producing a diffractive optical element and diffractive optical element produced by such a method
View Patent ↗A microlithography projection exposure system has an illumination system with an illumination optical system. The latter can have at least one diffractive optical element, which is divided into multiple adjacently arranged individual elements, each of which has one specified bundle-forming and polarizing effect.
1. A method comprising:
a) optically polishing a surface of a first substrate;
after a), b) joining the optically polished surface of the first substrate to a second substrate, the second substrate comprising an optically polarization-active material;
after b), c) forming multiple adjacently arranged elements into the first substrate; and
after c), d) removing portions of the second substrate at locations corresponding to the elements,
wherein, for each of the elements, when a bundle of light is incident on the element, the element has a bundle forming effect on a part of the bundle of light.
2. The method according to claim 1 , wherein c) comprises:
generating fins in the first substrate; and
stripping the fins in sections.
3. The method according to claim 1 , wherein the first substrate is joined to the second substrate by matchingly thrusting both substrates jointly together.
4. The method according to claim 1 , wherein d) comprises:
forming etch structures in the second substrate, the etch structures having etch projecting ends therebetween; and
heating the etch projecting ends until portions of the second substrate are detached from the first substrate.
5. The method according to claim 4 , wherein the etch structures are located along the periphery of the portions of the second substrate that are detached by the heating.
6. The method according to claim 4 , wherein heating comprises laser irradiation.
7. The method according to claim 1 , further comprising, after b) and before d), polishing of an outer surface of the first and second substrates to a achieve a desired thickness of the first and second substrates.
8. The method according to claim 1 , further comprising reducing the layer thickness of the second substrate.
9. The method according to claim 1 , further comprising joining the first and second substrates to a third substrate, the third substrate comprising an optically doubly refracting material.
10. A diffractive optical element produced according to a method according to claim 1 .
11. A system, comprising:
at least one diffractive optical element produced according to a method according to claim 1 ,
wherein the system is an illumination optical system.
12. A system, comprising:
an illumination optical system comprising at least one diffractive optical element produced according to claim 1 ,
wherein the system is a microlithography projection exposure system.
13. A method, comprising:
using a microlithography projection exposure system to form a micro-electronic component, the microlithography projection exposure system comprising an illumination system comprising at least one diffractive optical element produced according to claim 1 .