X-ray lithography beamline imaging system

Claim 1

A method for imaging an X-ray lithography beamline from an X-ray source emitting an X-ray beam along a y axis and diverging along x and z axes, respectively, where the x, y and z axes are orthogonal to each other, comprising: providing a mirror having a reflecting surface reflecting the X-ray beam to an imaging plane orthogonal to the y axis and spaced from the mirror along the y axis; determining the optical path function F from the source A to the image B by determining the optical path function from the source A to the mirror P, and from the mirror P to the image B, according to F=AP+PB=((x.sub.A -x).sup.2 +(y.sub.A -y).sup.2 +(z.sub.A -z).sup.2).sup.1/2 +((x.sub.B -x).sup.2 +(y.sub.B -y).sup.2 +(z.sub.B -z).sup.2).sup.1/2 where x A is the position of the source A along the x axis, y A is the position of the source along the y axis, z A is the position of the source along the z axis, x B is the position of the image along the x axis, y B is the position of the image along the y axis, z B is the position of the image along the z axis, x is the position on the mirror along the x axis, y is the position on the mirror along the y axis, and z is the position on the mirror along the z axis, such that A(x A , y A , z A ) is the source position, B(x B , y B , z B ) is the image position, and P(x, y, z) is the position on the mirror; determining the partial derivatives of the optical path function F, ∂F/∂x, ∂F/∂y, ∂F/∂z, wherein the displacement of reflected rays from the image line along the x axis is zero, Δx=0, if ∂F/∂x=0, the displacement of reflected rays from the image line along the y axis is zero, Δy=0, if ∂F/∂y=0, and the displacement of reflected rays from the image line along the z axis is zero, Δz=0, if ∂F/∂z=0; determining a grid on said reflecting surface comprising a plurality of grid points; and modifying the slope at said grid points such that the displacement of the reflected rays from the image line vanishes.

Claim 2

A method for imaging an X-ray lithography beamline from an X-ray source emitting an X-ray beam along a y axis and diverging along x and z axes, respectively, where the x, y and z axes are orthogonal to each other, comprising: providing a mirror having a reflecting surface reflecting the X-ray beam to an imaging plane orthogonal to the y axis and spaced from the mirror along the y axis; determining the optical path function F from the source A to the image B by determining the optical path function from the source A to the mirror P, and from the mirror P to the image B, according to F=AP+PB=((x.sub.A -x).sup.2 +(y.sub.A -y).sup.2 +(z.sub.A -z).sup.2).sup.1/2 +((x.sub.B -x).sup.2 +(y.sub.B -y).sup.2 +(z.sub.B -z).sup.2).sup.1/2 where x A is the position of the source A along the x axis, y A is the position of the source along the y axis, z A is the position of the source along the z axis, x B is the position of the image along the x axis, y B is the position of the image along the y axis, z B is the position of the image along the z axis, x is the position on the mirror along the x axis, y is the position on the mirror along the y axis, and z is the position on the mirror along the z axis, such that A(x A , y A , z A ) is the source position, B(x B , y B , z B ) is the image position, and P(x, y, z) is the position on the mirror; determining the partial derivatives of the optical path function F, ∂F/∂x, ∂F/∂y, ∂F/∂z, wherein the displacement of reflected rays from the image line along the x axis is zero, Δx=0, if ∂F/∂x=0, the displacement of reflected rays from the image line along the y axis is zero, Δy=0, if ∂F/∂y=0, and the displacement of reflected rays from the image line along the z axis is zero, Δz=0, if ∂F/∂z=0; determining a grid on said reflecting surface comprising a plurality of grid points; and modifying the slope at said grid points such that the displacement of the reflected rays from the image line vanishes.