Several lithographic techniques are used for patterning in the nanoscale region. This article examines X-Ray Lithography
How X-Ray Lithography Works
The X-ray lithography process is almost identical to photolithography and extreme ultraviolet lithography but uses a mask is made from an X-ray transparent material with a pattern of high Z material either etched or deposited on it. Exposure of the substrate resist is done using a parallel beam of X-rays.
The X-Ray source begins with an electron beam than is converted to an X-Ray beam in a synchrotron. At the time of writing a synchrotron costs in the vicinity of $25million making X-Ray Lithography an expensive process.
Figure 1. Basic illustration of how X-Ray Lithography works
Applications for X-Ray lithography are the same as those for other optical based lithographic techniques such as photolithography. These applications most commonly include computer chips and other semiconductor related devices.
The resolution of the etched pattern depends upon the mask features and exposure control but is lower than 50nm and theoretically can be much lower.