Femtosecond Laser Machining of an X-ray Mask in a 500 Micron-Thick Tungsten Sheet
Femtosecond laser material processing (FLMP) was used to make an X-ray mask in a 500 µm thick tungsten sheet without the use of any chemical etch methods. The laser produced an 800 nm wavelength at a 1 kHz repetition rate and a pulse width of 100 fs. The laser beam arrival at the tungsten sheet was...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-11-01
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| Series: | Micromachines |
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| Online Access: | https://www.mdpi.com/2072-666X/14/11/2071 |
| _version_ | 1797458353608196096 |
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| author | Ebenezer Owusu-Ansah Colin Dalton |
| author_facet | Ebenezer Owusu-Ansah Colin Dalton |
| author_sort | Ebenezer Owusu-Ansah |
| collection | DOAJ |
| description | Femtosecond laser material processing (FLMP) was used to make an X-ray mask in a 500 µm thick tungsten sheet without the use of any chemical etch methods. The laser produced an 800 nm wavelength at a 1 kHz repetition rate and a pulse width of 100 fs. The laser beam arrival at the tungsten sheet was synchronized to a computer numerically controlled (CNC) stage that allowed for motion in the XYZθ directions. The X-ray mask design was made using CAD/CAM software (Alphacam 2019 R1) and it consisted of linear, circular, and 45° angle features that covered an area of 10 mm × 10 mm. A total of 70 laser beam passes at a moderate laser energy of 605.94 J/cm<sup>2</sup> were used to make through-cut features into the tungsten sheet. The morphology of the top view (laser incident, LS) images showed cleaner and smoother cut edges relative to the bottom view (laser exit, LE) images. It was found that the size dimensions of the through-cut features on the LE surfaces were better aligned with the CAD dimensions than those of the LS surfaces. The focused laser beam produced inclined cut surfaces as the beam made the through cut from the LS to the LE of the tungsten sheet. The circular features at the LS surface deviated toward being oval-like on the LE surface, which could be compensated for in future CAD designs. The dependence of the CNC processing speed on the thickness of the etch depth was determined to have a third-order exponential decay relationship, thereby producing a theoretical model that will be useful for future investigators to predict the required experimental parameters needed to achieve a known etch depth in tungsten. This is the first study that has demonstrated the capability of using a femtosecond laser to machine through-cut an X-ray mask in a 500 µm thick tungsten sheet with no involvement of a wet etch or any other such supporting process. |
| first_indexed | 2024-03-09T16:35:53Z |
| format | Article |
| id | doaj.art-0b7abf2f2078440fa8bc0d548ed3c341 |
| institution | Directory Open Access Journal |
| issn | 2072-666X |
| language | English |
| last_indexed | 2024-03-09T16:35:53Z |
| publishDate | 2023-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Micromachines |
| spelling | doaj.art-0b7abf2f2078440fa8bc0d548ed3c3412023-11-24T14:56:27ZengMDPI AGMicromachines2072-666X2023-11-011411207110.3390/mi14112071Femtosecond Laser Machining of an X-ray Mask in a 500 Micron-Thick Tungsten SheetEbenezer Owusu-Ansah0Colin Dalton1Department of Electrical & Software Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, CanadaDepartment of Electrical & Software Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, CanadaFemtosecond laser material processing (FLMP) was used to make an X-ray mask in a 500 µm thick tungsten sheet without the use of any chemical etch methods. The laser produced an 800 nm wavelength at a 1 kHz repetition rate and a pulse width of 100 fs. The laser beam arrival at the tungsten sheet was synchronized to a computer numerically controlled (CNC) stage that allowed for motion in the XYZθ directions. The X-ray mask design was made using CAD/CAM software (Alphacam 2019 R1) and it consisted of linear, circular, and 45° angle features that covered an area of 10 mm × 10 mm. A total of 70 laser beam passes at a moderate laser energy of 605.94 J/cm<sup>2</sup> were used to make through-cut features into the tungsten sheet. The morphology of the top view (laser incident, LS) images showed cleaner and smoother cut edges relative to the bottom view (laser exit, LE) images. It was found that the size dimensions of the through-cut features on the LE surfaces were better aligned with the CAD dimensions than those of the LS surfaces. The focused laser beam produced inclined cut surfaces as the beam made the through cut from the LS to the LE of the tungsten sheet. The circular features at the LS surface deviated toward being oval-like on the LE surface, which could be compensated for in future CAD designs. The dependence of the CNC processing speed on the thickness of the etch depth was determined to have a third-order exponential decay relationship, thereby producing a theoretical model that will be useful for future investigators to predict the required experimental parameters needed to achieve a known etch depth in tungsten. This is the first study that has demonstrated the capability of using a femtosecond laser to machine through-cut an X-ray mask in a 500 µm thick tungsten sheet with no involvement of a wet etch or any other such supporting process.https://www.mdpi.com/2072-666X/14/11/2071ultrafast laserslaser ablationultrafast laser processingfemtosecond laser pulsefemtosecond laser material processing (FLMP)computer numerically controlled (CNC) motion |
| spellingShingle | Ebenezer Owusu-Ansah Colin Dalton Femtosecond Laser Machining of an X-ray Mask in a 500 Micron-Thick Tungsten Sheet Micromachines ultrafast lasers laser ablation ultrafast laser processing femtosecond laser pulse femtosecond laser material processing (FLMP) computer numerically controlled (CNC) motion |
| title | Femtosecond Laser Machining of an X-ray Mask in a 500 Micron-Thick Tungsten Sheet |
| title_full | Femtosecond Laser Machining of an X-ray Mask in a 500 Micron-Thick Tungsten Sheet |
| title_fullStr | Femtosecond Laser Machining of an X-ray Mask in a 500 Micron-Thick Tungsten Sheet |
| title_full_unstemmed | Femtosecond Laser Machining of an X-ray Mask in a 500 Micron-Thick Tungsten Sheet |
| title_short | Femtosecond Laser Machining of an X-ray Mask in a 500 Micron-Thick Tungsten Sheet |
| title_sort | femtosecond laser machining of an x ray mask in a 500 micron thick tungsten sheet |
| topic | ultrafast lasers laser ablation ultrafast laser processing femtosecond laser pulse femtosecond laser material processing (FLMP) computer numerically controlled (CNC) motion |
| url | https://www.mdpi.com/2072-666X/14/11/2071 |
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