Low-order wavefront error account for a large proportion of wave aberrations.A compensation method for low order aberration of projection lithography objective based on Interior Point Method is presented.Compensation ...Low-order wavefront error account for a large proportion of wave aberrations.A compensation method for low order aberration of projection lithography objective based on Interior Point Method is presented.Compensation model between wavefront error and degree of movable lens freedom is established.Converting over-determined system to underdetermined system,the compensation is solved by Interior Point Method(IPM).The presented method is compared with direct solve the over-determined system.Then,other algorithm GA,EA and PS is compared with IPM.Simulation and experimental results show that the presented compensation method can obtained compensation with less residuals compared with direct solve the over-determined system.Also,the presented compensation method can reduce computation time and obtain results with less residuals compare with AGA,EA and PS.Moreover,after compensation,RMS of wavefront error of the experimental lithography projection objective decrease from 56.05 nm to 17.88 nm.展开更多
A 95 W Nd：YAG laser system pumped by a vertical cavity surface emitting laser（VCSEL） array is described.The laser contains an all-fiber-based seeder, an Nd：YAG regenerative amplifier, and a four-pass amplifier. Th...A 95 W Nd：YAG laser system pumped by a vertical cavity surface emitting laser（VCSEL） array is described.The laser contains an all-fiber-based seeder, an Nd：YAG regenerative amplifier, and a four-pass amplifier. The laser operates at 300 Hz with energies up to 317 m J. The beam has a top-hat intensity distribution. The temporal pulse shape is flat in time, and the pulse width can be adjusted in the range of 2–6 ns.展开更多
We present a Fizeau interferometer using a microscopic objective as a tool for surface contouring without the need for a numerical lens for reconstruction. The interferometer is associated with a telescope system to f...We present a Fizeau interferometer using a microscopic objective as a tool for surface contouring without the need for a numerical lens for reconstruction. The interferometer is associated with a telescope system to feature the object with collimated light. The experiment is conducted on two objects possessing different step heights.The phase maps from the captured off-axis holograms are calculated numerically, which allows us to deduce the contours of the objects. The great advantages of the presented technique are that it can be done in real time and there is no need for numerical lenses for micro-objects reconstruction.展开更多
文摘Low-order wavefront error account for a large proportion of wave aberrations.A compensation method for low order aberration of projection lithography objective based on Interior Point Method is presented.Compensation model between wavefront error and degree of movable lens freedom is established.Converting over-determined system to underdetermined system,the compensation is solved by Interior Point Method(IPM).The presented method is compared with direct solve the over-determined system.Then,other algorithm GA,EA and PS is compared with IPM.Simulation and experimental results show that the presented compensation method can obtained compensation with less residuals compared with direct solve the over-determined system.Also,the presented compensation method can reduce computation time and obtain results with less residuals compare with AGA,EA and PS.Moreover,after compensation,RMS of wavefront error of the experimental lithography projection objective decrease from 56.05 nm to 17.88 nm.
文摘A 95 W Nd：YAG laser system pumped by a vertical cavity surface emitting laser（VCSEL） array is described.The laser contains an all-fiber-based seeder, an Nd：YAG regenerative amplifier, and a four-pass amplifier. The laser operates at 300 Hz with energies up to 317 m J. The beam has a top-hat intensity distribution. The temporal pulse shape is flat in time, and the pulse width can be adjusted in the range of 2–6 ns.
基金supported by the Chinese Academy of Sciences Fellowship for Postdoctoral and Visiting Scholars from Developing Countries
文摘We present a Fizeau interferometer using a microscopic objective as a tool for surface contouring without the need for a numerical lens for reconstruction. The interferometer is associated with a telescope system to feature the object with collimated light. The experiment is conducted on two objects possessing different step heights.The phase maps from the captured off-axis holograms are calculated numerically, which allows us to deduce the contours of the objects. The great advantages of the presented technique are that it can be done in real time and there is no need for numerical lenses for micro-objects reconstruction.
