CN101198433A - 使用激光对热敏介电材料进行精抛光/精密结构化的方法 - Google Patents
使用激光对热敏介电材料进行精抛光/精密结构化的方法 Download PDFInfo
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- B—PERFORMING OPERATIONS; TRANSPORTING
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Abstract
本发明涉及一种对热敏介电材料特别是热膨胀系数小的介电材料使用激光辐射进行精抛光/精密结构化的方法。使用这种方法,将强超短波激光照射到材料待加工的表面上,激光对材料表面的作用时间在10-13秒至10-11秒范围内,激光脉冲能量控制在烧蚀极限以下,但是足可以调节库仑爆炸的发生。采用按照本发明的方法,材料在纳米范围内的去除量利用超短波激光脉冲在皮秒和亚皮秒时间范围中就可以完成,其间,在精密烧蚀工艺步骤(去除量在烧蚀极限以下),材料表面即被精抛光。由于对等待加工表面的激光辐射作用时间极短,温升很小,仅在十几度左右。
Description
本发明涉及一种使用激光对热敏介电材料进行精抛光/精密结构化的方法。
超精密技术包括对物体及其表面以宏观尺寸对形状和光滑度进行极其精密加工的加工方法。表面被平整和成形得越精密,其光学性能就越好。为此,就必须研究对各种不同材料的加工,因为光学可用波长的光谱相当宽。除了能够生产更为光滑平整和成形更为精确的用于可见光范围的透镜外,还越来越多地要求用于红外线-乃至紫外线和X光领域的镜组。为此必须通过把常规的和全新制造工艺相结合,提高抛光技术的完美化水平。
除了传统的机械方法,目前基本上公开了两种利用辐射对材料抛光的方法。
一种是使用离子束对介电材料做精抛光的方法,另一种则是使用CO2-激光方法。再有就是近来出现了一种用YAG-激光进行金属抛光的方法。
这两种激光方法都需要短时间地熔化表面,以将不平整部位处理光滑平整,达到抛光效果。其间,表面的能量密度必须选择得只出现显微小峰值的熔化和气化,而不会产生破坏结构的处理。例如对于光导纤维的末端使用CO2-激光进行加工以传播更高的激光功率,应用光学杂志第39卷33,20期,2000年11月,第6136-6143页对此已有说明。使用YAG-激光对外形复杂的金属材料进行抛光(参见DGM AKTUELL杂志2001年3月第12期“激光抛光金属”和/或DE 102 28 743 A1),对此先前大部分需要通过手工操作。这两种激光工艺由于它们的熔化过程都不适合对温度敏感的材料,像微晶玻璃(Zerodur)。在这些材料上,对表面的平整处理只能在温度没有显著升高的条件下才能进行。
所以对此类材料的精密抛光,目前只使用离子束。可是它的缺点是必须要有一台真空设备,需要处理的工件越大,设备的耗费也就越高。
本发明的目的在于:提出一种使用激光辐射对热敏介电材料,特别是对热膨胀系数小的材料进行精抛光/精密结构化的方法。
上述目的根据本发明通过一种方法得以解决。使用这种方法,将强超短波激光照射到材料待加工的表面上,激光对材料表面的作用时间在10-13秒至10-11秒范围内,激光脉冲能量控制在电蚀极限以下,但是足可以调节库仑爆炸的发生。
采用按照本发明的方法,纳米范围内的材料去除量用超短波激光脉冲在皮秒和亚皮秒时间范围里就可以实现,其中在前电蚀工艺步骤过程中(去除量在电蚀极限以下),材料表面被精抛光。由于对待加工表面的激光辐射作用时间极短,温升很小,仅仅在几个10度以内。所以,这种按照本发明的方法也可以说成是一种冷加工方法。这种方法可在空气中进行,意味着不再需要耗费很大的真空设备,而且还可以根据样品去除量实施在线联机控制。
采用按照本发明的解决办法,可以利用上面已经提到过的库仑爆炸效应(在物理学周报(Phys.Rev.)B 62(2000)13167-13173页,物理学周报信函(Phys.Rev.Letters)88(2002)097603;应用物理杂志A 79(2004)1153-1155页里已经举例说明)。利用这种效应,强超短波激光对材料表面的辐射只会在接近表面的区域内剥蚀掉极其微少的材料(0,1到不多的几个纳米)。其间,通过光化电离测定表面的电子,电子数目之多,致使接近表面区域中残留的离子处于相当高的静电应力之下,从而造成这些离子分离。
为了调节到需要的能量密度,已经在一种实施方式中把激光向待加工表面的辐射流通量调整在极限流通量的70%和95%之间。将待加工的表面安置在激光光束的焦点之前,就可以做到这点。
在另外一种实施形式下,利用激光束对待加工表面用进行扫描。由于根据本发明的工艺是在空气中操作的,所以这通过公知的手段就可以相对简单地实施。
下面,结合附图来详细说明一个实施例。
附图说明:
图1:本发明实施例原理示意图
图2:经过按照本发明的方法加工后的表面
实施例中,微晶玻璃(Zerodur)的表面已经用本发明的方法加工。在此过程中,激光束借助一个透镜在试样方向聚焦,其中如图1中所示,试样表面处于焦点前。试样表面的位置要选择得让激光流通量F达到极限流通量Fth的约70%至95%。不可以在焦点后定位,因为很高的激光强度可能使得等离子体在空气中在焦点区域被击穿,致使破坏光束的轮廓,造成能量损耗。此外,在激光束里还装上了一个矩形光阑,以尽量模拟出一种礼帽(Tophat-)轮廓。虽然试样内部(干扰部位)也出现了变形,但是太深,对试样表面不起作用。由于扫描方法的剥蚀量就其与成像法相比所达到的粗糙度要小,从而被证实是一种更有希望的工艺方法,因此才选中这种礼帽(Tophat-)轮廓。在这个实施例中,试样表面用激光束做条带状照射,一条紧挨着一条。在采用超短波激光原始轮廓(高斯轮廓)的情况下,条带重叠因试样表面的粗糙度而不够充分,所以也采用了这种模拟的礼帽(Tophat-)轮廓。
这种类型的礼帽(Tophat-)轮廓也可以通过一个可控衍射光学元件(DOE)制造出来,说得更确切些,使用这种DOE,同样可以在待加工表面上制做出一个理想的礼帽(Tophat-)轮廓。
曾经使用过一种商业上通用的波长800纳米脉冲宽度50飞秒的加强TiSa-系统做为激光系统。至今没有进行过波长变动的尝试,只考虑起始辐射的第二谐波(大约400纳米)的波长为可用波长,因为采用这种波长才能有足够的能量供使用。
图2显示了一条使用本发明的方法在剥蚀极限以下用运行速度0,1mm/s电蚀制造出来的宽条带。这里,流通量F为大约80%的极限流动量,就是说,1,6J/cm2即为材料剥蚀最理想的流通量值。试样距一个50mm-透镜的焦点为3,9mm。每次脉冲的激光能量在矩形光阑后为0,9mJ,激光的重复脉冲频率为700Hz。这就意味着,在按照本发明的方法中,大约有500次脉冲冲击到试样差不多同一部位上。共并排拉了20条线,相互之间的间距Δz=70μm。附图显示出一种对称均匀的剥蚀状况,看不出一道道的线条。当然还可以并排设置更多条的直线。其结果就是在试样整个面上的电蚀。按照本发明的方法加工的表面的粗糙度为rms-粗糙度=1±0,15nm。
Claims (5)
1.使用激光对热敏介电材料进行精抛光/精密结构化的方法,其特征在于:将强超短波激光照射到材料待加工的表面上,激光对材料表面的作用时间在10-13秒至10-11秒范围内,激光脉冲能量控制在电蚀极限以下,但是足可以调节库仑爆炸的发生。
2.如权利要求1所述的方法,其特征在于:待加工表面上激光辐射的流通量应调节在电蚀极限的70%和95%之间。
3.如权利要求2所述的方法,其特征在于:待加工的表面置放于激光束焦点的前面。
4.如权利要求1所述的方法,其特征在于:用激光束对待加工表面进行扫描。
5.如权利要求4所述的方法,其特征在于:向待加工表面发射的激光束的外形,应调整成一种礼帽(Tophat-)轮廓。
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US (1) | US20080143021A1 (zh) |
EP (1) | EP1871566B1 (zh) |
JP (1) | JP2008538324A (zh) |
KR (1) | KR20080003900A (zh) |
CN (1) | CN101198433A (zh) |
AT (1) | ATE527080T1 (zh) |
CA (1) | CA2604641A1 (zh) |
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Cited By (4)
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CN107498176A (zh) * | 2017-08-02 | 2017-12-22 | 中国科学院光电研究院 | 一种多孔陶瓷的准分子激光抛光及检测方法 |
CN107873087A (zh) * | 2015-06-19 | 2018-04-03 | 临床激光热疗系统公司 | 侧向发射的光波导和用于向光波导中引入微修饰的方法 |
CN108620725A (zh) * | 2017-12-19 | 2018-10-09 | 嘉兴迪迈科技有限公司 | 一种激光玻璃的抛光方法 |
US11713546B2 (en) | 2019-09-27 | 2023-08-01 | Sin Woo Co., Ltd. | Method for manufacturing paper buffer tray for packaging and buffer tray manufactured thereby |
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WO2007149460A2 (en) * | 2006-06-20 | 2007-12-27 | Chism William W | Method of direct coulomb explosion in laser ablation of semiconductor structures |
EP2430649A4 (en) * | 2009-05-15 | 2014-07-16 | Translith Systems Llc | METHOD AND APPARATUS FOR CONTROLLED LASER ABLATION OF MATERIAL |
DE102010023568A1 (de) * | 2010-06-08 | 2011-12-08 | Forschungsverbund Berlin E.V. | Verfahren und Vorrichtung zum Herstellen nanostrukturierter Oberflächen |
US9849512B2 (en) * | 2011-07-01 | 2017-12-26 | Attostat, Inc. | Method and apparatus for production of uniformly sized nanoparticles |
JP5890739B2 (ja) * | 2012-04-19 | 2016-03-22 | 住友電工ハードメタル株式会社 | 切削工具およびその製造方法 |
DE102012010635B4 (de) | 2012-05-18 | 2022-04-07 | Leibniz-Institut für Oberflächenmodifizierung e.V. | Verfahren zur 3D-Strukturierung und Formgebung von Oberflächen aus harten, spröden und optischen Materialien |
WO2016161348A1 (en) | 2015-04-01 | 2016-10-06 | Attostat, Inc. | Nanoparticle compositions and methods for treating or preventing tissue infections and diseases |
CN107614629A (zh) | 2015-04-13 | 2018-01-19 | 阿托斯塔特公司 | 抗腐蚀纳米颗粒组合物 |
US11473202B2 (en) | 2015-04-13 | 2022-10-18 | Attostat, Inc. | Anti-corrosion nanoparticle compositions |
DE102015119325A1 (de) | 2015-11-10 | 2017-05-11 | Leibniz-Institut für Oberflächenmodifizierung e.V. | Verfahren zur Glättung von Oberflächen eines Werkstücks |
US10201571B2 (en) | 2016-01-25 | 2019-02-12 | Attostat, Inc. | Nanoparticle compositions and methods for treating onychomychosis |
EP3580013A4 (en) * | 2017-02-09 | 2020-12-16 | US Synthetic Corporation | ENERGY-PROCESSED POLYCRYSTALLINE DIAMOND COMPACT AND ASSOCIATED PROCESSES |
US11018376B2 (en) | 2017-11-28 | 2021-05-25 | Attostat, Inc. | Nanoparticle compositions and methods for enhancing lead-acid batteries |
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CN113828929B (zh) * | 2021-10-27 | 2022-10-04 | 西安交通大学 | 抛光机、复合激光抛光及修复高熵合金增材制件的方法 |
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US5800625A (en) * | 1996-07-26 | 1998-09-01 | Cauldron Limited Partnership | Removal of material by radiation applied at an oblique angle |
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US6830993B1 (en) * | 2000-03-21 | 2004-12-14 | The Trustees Of Columbia University In The City Of New York | Surface planarization of thin silicon films during and after processing by the sequential lateral solidification method |
US20020046995A1 (en) * | 2000-05-02 | 2002-04-25 | Chang Yong-Joon Andrew | Method for forming microchannels by scanning a laser |
DE10125206B4 (de) * | 2001-05-14 | 2005-03-10 | Forschungsverbund Berlin Ev | Verfahren zur direkten Mikrostrukturierung von Materialien |
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DE10228743B4 (de) * | 2002-06-27 | 2005-05-04 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Verfahren zum Glätten und Polieren von Oberflächen durch Bearbeitung mit Laserstrahlung |
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Cited By (5)
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CN107873087A (zh) * | 2015-06-19 | 2018-04-03 | 临床激光热疗系统公司 | 侧向发射的光波导和用于向光波导中引入微修饰的方法 |
CN107498176A (zh) * | 2017-08-02 | 2017-12-22 | 中国科学院光电研究院 | 一种多孔陶瓷的准分子激光抛光及检测方法 |
CN107498176B (zh) * | 2017-08-02 | 2019-05-14 | 中国科学院光电研究院 | 一种多孔陶瓷的准分子激光抛光及检测方法 |
CN108620725A (zh) * | 2017-12-19 | 2018-10-09 | 嘉兴迪迈科技有限公司 | 一种激光玻璃的抛光方法 |
US11713546B2 (en) | 2019-09-27 | 2023-08-01 | Sin Woo Co., Ltd. | Method for manufacturing paper buffer tray for packaging and buffer tray manufactured thereby |
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CA2604641A1 (en) | 2006-10-26 |
WO2006111446A1 (de) | 2006-10-26 |
EP1871566B1 (de) | 2011-10-05 |
DE102005020072A1 (de) | 2006-11-02 |
ATE527080T1 (de) | 2011-10-15 |
EP1871566A1 (de) | 2008-01-02 |
JP2008538324A (ja) | 2008-10-23 |
US20080143021A1 (en) | 2008-06-19 |
DE102005020072B4 (de) | 2007-12-06 |
KR20080003900A (ko) | 2008-01-08 |
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