| 主权项 |
1. A method for manufacturing a compound refractive lens for focusing X-rays in two dimensions, the compound refractive lens comprising a mother lens and a daughter lens, and the method comprising preparation of the mother lens, preparation of the daughter lens, and assembly of the mother lens and the daughter lens, wherein:
1) the preparation of the mother lens comprises:
a) using a glass substrate-chrome material to prepare a photolithographic mask of the mother lens by using an electron beam lithography; the photolithographic mask of the mother lens comprising a plurality of first parabola-shaped holes and a plurality of square holes arranged coaxially at intervals; a cross section of each of the first parabola-shaped holes being formed by connecting openings of two symmetrical parabolas; the number of the square holes being n, and a side length of the square hole being 1+δ, wherein n is an integer from 20 and 100, and δ is within the range of between 1 and 2 μm;b) cleaning a glass substrate;c) depositing a copper, aluminum, or gold film on the cleaned glass substrate as an electroforming cathode film using a sputtering method or an evaporation method;d) spin coating a layer of a BP212 positive photoresist on the electroforming cathode film; baking, and curing the positive photoresist;e) spin coating a layer of a SU-8 photoresist having a thickness of 1 on the BP212 positive photoresist;f) exposing, developing, and hardening the coated SU-8 photoresist using the photolithographic mask of the mother lens prepared in step a);g) washing a first sample piece obtained from step f), and removing an exposed BP212 positive photoresist from an upper surface of the sample piece;h) placing the first sample piece treated by step g) in an electroforming solution for electroforming, the electroforming material being copper, nickel, iron, or chromium;i) taking the first sample piece out of the electroforming solution when a thickness of the electroforming material is the same as the thickness of the SU-8 photoresist, both being 1; and washing the first sample piece to remove remaining electroforming solution;j) immersing the first sample piece in an acetone solution; removing the BP212 positive photoresist and the SU-8 photoresist adhering on the BP212 photoresist to yield the mother lens; 2) the preparation of the daughter lens comprises:
k) using a glass substrate-chrome material to prepare a photolithographic mask of the daughter lens by using the electron beam lithography; the photolithographic mask of the daughter lens comprising a clamping arm and a plurality of square embedded lens bodies coaxially arranged on the clamping arm; the number of the square embedded lens bodies being n, which is the same as the number of the square holes of the mother lens; each of the square embedded lens bodies comprising a second parabola-shaped hole having a cross section formed by connecting openings of two symmetrical parabolas; a center of the second parabola-shaped hole and a center of the square embedded lens body coincide; the square embedded lens body having a side length of 1; the square embedded lens body and the clamping arm being integrated as a whole body; and a thickness of the clamping arm being t;l) cleaning a silicon substrate;m) spin coating a layer of BP212 photoresist on a surface of the silicon substrate; and pre-baking the silicon substrate to yield a second sample piece;n) depositing a copper, aluminum, or gold film on the second sample piece obtained from step m) as an electroforming cathode film using the sputtering method or the evaporation method;o) spin coating a layer of KMP C5315 photoresist on the second sample piece from step n);p) spin coating a layer of SU-8 photoresist having a thickness of 1 on the second sample piece from step o);q) exposing, developing, and hardening the coated SU-8 photoresist using the photolithographic mask of the daughter lens prepared in step k);r) removing an exposed KMP C5315 photoresist from an upper surface using a degumming agent of KMP C5315;s) placing the second sample piece treated by step r) in an electroforming solution for electroforming, the electroforming material being copper, nickel, iron, or chromium but different from the material of the electroforming cathode film;t) taking the second sample piece out of the electroforming solution when a thickness of the electroforming material is the same as the thickness of the SU-8 photoresist, both being 1; and washing the second sample piece to remove remaining electroforming solution;u) immersing the second sample piece in an acetone solution; removing the KMP C5315 photoresist and the SU-8 photoresist adhering on the KMP C5315 photoresist, and meanwhile removing the BP212 photoresist and the silicon substrate;v) removing the electroforming cathode film from the second sample piece after treatment of step u) using a method of chemical etching to yield the daughter lens; and 3) the assembly of the mother lens and the daughter lens comprises:
w) placing the mother lens and the daughter lens beneath a microscope, finding and clamping the clamping arm of the daughter lens, aligning the square embedded lens bodies of the daughter lens with the square holes of the mother lens, respectively, for allowing the first parabola-shaped holes and the second parabola-shaped holes to form an orthogonal structure and allowing the n square embedded lens bodies of the daughter lens to fit the n square holes of the mother lens, respectively; and inserting and pressing the square embedded lens bodies into the corresponding square holes, respectively. |
