APPARATUS AND METHOD FOR PROCESSING OR IMAGING A SAMPLE
The invention relates to an apparatus and method for exposing a sample. The apparatus comprises a source for electromagnetic radiation or particles having energy, an exposing unit for exposing said sample to said electromagnetic radiation or particles, and a substrate holding device for holding said sample at least during said exposing. The exposing unit comprises a component for manipulating and/or blocking at least part of the electromagnetic radiation or charged particles. The component comprises a cooling arrangement which is arranged for substantially maintaining the component at a predetermined first temperature. The substrate holding device comprises a temperature stabilizing arrangement which is arranged to substantially stabilize the temperature of a sample arranged on said substrate holding device. The temperature stabilizing arrangement comprises a phase change material having a phase change at a second temperature, which is at or near the first temperature.
1 . Apparatus for exposing a sample, wherein said apparatus comprises
a source for electromagnetic radiation or particles having energy,
an exposing unit for exposing said sample to said electromagnetic radiation or particles, wherein the exposing unit comprises a component for at least partially and/or temporally manipulating and/or blocking at least part of the electromagnetic radiation or charged particles, wherein the component comprises a cooling arrangement which is arranged for substantially maintaining the component at a predetermined first temperature, and
a substrate holding device for holding said sample at least during said exposing, wherein the substrate holding device comprises a temperature stabilizing arrangement which is arranged to substantially stabilize the temperature of a sample arranged on said substrate holding device, wherein the temperature stabilizing arrangement comprises a phase change material having a phase change at a second temperature,
wherein the cooling arrangement and the temperature stabilizing arrangement are arranged such that the second temperature is at or near the first temperature.
2 . Apparatus according to claim 1 , wherein the cooling arrangement and the temperature stabilizing arrangement are arranged such that a difference between the first temperature and the second temperature is not more than 4° C., preferably not more than 2° C.
3 . Apparatus according to claim 1 , wherein the first temperature is lower than the second temperature.
4 . Apparatus according to claim 1 , wherein the first temperature is substantially equal to the second temperature, preferably wherein the first temperature and the second temperature are substantially equal to room temperature, in particular to room temperature in a Fabrication Plant (Fab).
5 . Apparatus according to claim 1 , wherein the phase change material comprises an Eutectic metal alloy.
6 . Apparatus according to claim 1 , wherein the cooling arrangement comprises conduits for guiding a cooling fluid through the conduits, wherein the conduits are arranged in thermal contact with the component.
7 . Apparatus according to claim 6 , wherein the cooling arrangement is arranged such that a difference between a temperature of the cooling fluid and the second temperature is not more than 4° C., preferably not more than 2° C.
8 . Apparatus according to claim 6 , wherein the cooling arrangement comprises a temperature control system which is arranged the control the temperature of the cooling fluid with respect to the temperature of the substrate holding device.
9 . Apparatus according to claim 8 , wherein the apparatus comprises temperature sensors for measuring the temperature of the substrate holding device and the temperature of the exposing unit, in particular the part of the exposing unit which is arranged adjacent the substrate holding device.
10 . Apparatus according to claim 8 , wherein the cooling arrangement comprising
a cooling device for cooling the cooling fluid to a temperature below the first temperature, and
a heating device for heating the cooling fluid, wherein the heating device is arranged in the conduits at an upstream position with respect to the component.
11 . Apparatus according to claim 1 , wherein the component comprises a projection lens for projecting the electromagnetic radiation or particles onto the sample.
12 . Apparatus according to claim 11 , wherein the cooling arrangement comprises conduits for guiding a cooling fluid through the conduits, wherein the conduits are arranged in thermal contact with the component, wherein the conduits are arranged for transporting the cooling fluid through or around the projection lens.
13 . Apparatus according to claim 1 , wherein the component comprises a modulation device for modulating the electromagnetic radiation or particles.
14 . Apparatus according to claim 13 , wherein the cooling arrangement comprises conduits for guiding a cooling fluid through the conduits, wherein the conduits are arranged in thermal contact with the component, wherein the conduits are arranged for transporting the cooling fluid through or around the modulation device.
15 . Apparatus according to claim 14 , wherein the modulation device comprises a beam blanking assembly comprising a beam deflector for deflecting a beam of electromagnetic radiation or particles and a beam stop for blocking said beam of electromagnetic radiation or particles, wherein the conduits are arranged for transporting the cooling fluid through or around the beam stop.
16 . Apparatus according to claim 1 , wherein the source is a source for charged particles and the exposing unit comprises a charged particle optical system for projecting one or more charged particle beams onto said sample.
17 . Apparatus according to claim 16 , wherein the source is arranged to provide multiple charged particle beams and wherein the charged particle optical system is arranged for projecting one or more of said multiple charged particle beams onto said sample, wherein at least a first part of the conduits is arranged in an area between two charged particle beams.
18 . Apparatus according to claim 1 , wherein the exposing unit comprises one or more temperature sensors, preferably wherein one of said one or more temperature sensor is arranged at a side of said exposing unit which faces the substrate holding device.
19 . Method for exposing a sample using an apparatus according to claim 1 , wherein a conditioning of the temperature stabilizing arrangement is performed prior to the processing or imaging of the sample, wherein the conditioning comprises the step of solidifying at least part of the liquid phase change material of said temperature stabilizing arrangement.
20 . Method according to claim 19 , wherein the conditioning further comprises the step of setting the temperature of the temperature stabilizing arrangement at the second temperature prior to the processing or imaging of the sample.
21 . (canceled)
22 . Method according to claim 19 , wherein a temperature of the apparatus during operation is in a temperature range from 19° C. to 22° C., preferably wherein the first temperature and the second temperature are also arranged in the temperature range from 19° C. to 22° C.
23 . Use of an apparatus according to claim 1 for exposing a sample, in particular for processing or imaging a sample.
24 . Method according to claim 19 , wherein the cooling arrangement of the apparatus comprises conduits for guiding a cooling fluid through the conduits, wherein the conduits are arranged in thermal contact with the component, wherein the cooling arrangement further comprises:
a cooling device for cooling the cooling fluid to a temperature below the first temperature, and
a heating device for heating the cooling fluid, wherein the heating device is arranged in the conduits at an upstream position with respect to the component.
wherein the method comprises the step of controlling at least one of the heating device and the cooling device to establish a temperature difference between the substrate holding device and the exposing unit, in particular the part of said exposing unit which faces the substrate holding device, which temperature difference is less than 4° C., preferably less than 2° C., more preferably less than 1° C.