Patent ID: 11914282
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A system of measuring an image of a pattern in a scanning type extreme ultraviolet (EUV) mask, comprising:
a high-power laser output unit comprising a flat mirror and a spherical mirror, which are used to focus a high-power femto-second laser on a gas cell;
a coherent EUV light generating portion comprising the gas cell, which is used to generate a coherent EUV light from light output from the high-power laser output unit;
a pin-hole, a graphene filter, and a zirconium (Zr) filter configured to remove a high-power laser beam from the coherent EUV light;
a stage, on which a reflection-type EUV mask is placed, and which is configured to move the reflection-type EUV mask in a direction of an x-axis or y-axis;
an x-ray spherical mirror configured to focus the coherent EUV light on a zone-plate lens and to improve optical efficiency;
a zone-plate lens placed between the stage and the x-ray spherical mirror to focus a reflected portion of the coherent EUV light on a region of the reflection-type EUV mask;
an x-ray flat mirror placed between the zone-plate lens and the x-ray spherical mirror to guide and reflect a beam, which is focused by the x-ray spherical mirror, to the zone-plate lens;
an order sorting aperture (OSA) placed on the stage and configured to transmit only a first-order diffraction light of the focused coherent EUV light; and
a detector portion placed on the stage and comprising a sensor array, which is configured to sense an energy distribution of the coherent EUV light according to an angle of the reflected portion of the coherent EUV light, when the transmitted first-order diffraction light, which is a portion of the focused coherent EUV light, is reflected by the region of the reflection-type EUV mask.