本文選題：飛秒激光 + 色散��； 參考：《北京理工大學(xué)》2016年博士論文

【摘要】：飛秒激光微/納制造是一個(gè)包含機(jī)械、熱力學(xué)、光學(xué)、材料等多個(gè)學(xué)科的前沿交叉領(lǐng)域,在國(guó)防、醫(yī)療、信息等方面均有廣泛應(yīng)用。飛秒激光具有超高的峰值功率,其與材料作用是一個(gè)從納米到毫米、從飛秒到微秒的非線性、非平衡多尺度過(guò)程,與傳統(tǒng)制造的機(jī)理完全不同,因此,研究飛秒激光微/納加工技術(shù),對(duì)物理及制造科學(xué)本身都有著極其重要的意義。隨著微小型化的進(jìn)一步發(fā)展,對(duì)制造品質(zhì)的要求不斷提高,因此,飛秒激光微/納制造也面臨著新的挑戰(zhàn),如更高的加工質(zhì)量,更高的加工效率和更好的加工可控性等。在理論上,飛秒激光與材料相互作用過(guò)程中,許多經(jīng)典理論已不再適用,材料光學(xué)及熱力學(xué)瞬時(shí)(飛秒)局部(納米)特性的變化極其重要,需要引入量子力學(xué),以提高其預(yù)測(cè)精度。在實(shí)驗(yàn)上,飛秒激光微/納加工是一個(gè)多參數(shù)過(guò)程,涉及波長(zhǎng)、波形、脈寬、頻率等,但是激光波形和脈寬會(huì)在激光傳輸過(guò)程中因色散的引入而導(dǎo)致畸變或展寬,影響加工的精度及可重復(fù)性;此外,飛秒激光加工的表面質(zhì)量、加工效率、可控性等仍需要進(jìn)一步提高。因此,針對(duì)上述科學(xué)問(wèn)題,本課題組基于電子動(dòng)態(tài)調(diào)控的思想,提出利用飛秒激光時(shí)域整形的方法,解決脈沖的畸變及展寬,通過(guò)調(diào)控光子與電子的相互作用,控制材料局部瞬時(shí)光學(xué)和熱力學(xué)特性,選擇性激發(fā)材料相變,實(shí)現(xiàn)高質(zhì)量、高效率、更高可控性的飛秒激光微/納制造新方法。本論文主要研究了基于電子動(dòng)態(tài)調(diào)控的時(shí)域整形飛秒激光加工非金屬材料(電介質(zhì)、聚合物和半導(dǎo)體),其主要內(nèi)容包括:1)以高斯光束為例,建立了飛秒激光在介質(zhì)中傳輸?shù)纳⒛Ｐ?理論模擬并分析了二階色散、三階色散對(duì)飛秒激光脈沖的脈寬及脈沖時(shí)域形狀的影響。2)建立了時(shí)域整形的飛秒激光與電介質(zhì)材料相互作用的量子等離子體模型,深入的研究了自由電子的激發(fā)電離、加熱以及材料瞬時(shí)局部光學(xué)特性的變化。3)搭建了時(shí)域整形的飛秒激光微/納加工光路系統(tǒng),系統(tǒng)的研究了時(shí)域整形飛秒激光參數(shù)對(duì)燒蝕彈坑的尺寸(直徑、深度)及表面質(zhì)量(重鑄、微裂紋)的影響規(guī)律。4)理論推導(dǎo)了基于雙光子聚合加工的特征尺寸與激光輻照參數(shù)的關(guān)系,利用時(shí)域整形的飛秒激光進(jìn)行聚合加工,實(shí)現(xiàn)了λ/12的極限分辨尺寸。5)提出了利用時(shí)域整形的飛秒激光高效率制備微流體通道的新方法,并研究了各參數(shù)對(duì)微通道加工效率的影響規(guī)律。6)研究了時(shí)域整形的飛秒激光直寫(xiě)加工半導(dǎo)體硅的各向異性現(xiàn)象,提出了通過(guò)調(diào)控飛秒激光的掃描速度、掃描方向和偏振方向,進(jìn)而調(diào)控半導(dǎo)體材料表面周期結(jié)構(gòu)的方向及幾何形貌。本論文所取得的主要?jiǎng)?chuàng)新成果總結(jié)如下:1)提出利用時(shí)域整形的飛秒激光加工電介質(zhì),通過(guò)調(diào)控電子激發(fā)、電離、復(fù)合及相變過(guò)程,實(shí)現(xiàn)高精度、高質(zhì)量的微/納加工新方法。首先,通過(guò)改變脈沖序列的子脈沖間隔,發(fā)現(xiàn)100 fs-200 fs之間燒蝕增強(qiáng)的新現(xiàn)象。其次,通過(guò)改變脈沖序列的子脈沖個(gè)數(shù),調(diào)控?zé)g結(jié)構(gòu)直徑和深度。最后,通過(guò)改變脈沖序列的能量分配比,實(shí)現(xiàn)對(duì)相變的選擇性激發(fā),從而減少重鑄,提高了材料的表面加工質(zhì)量。2)提出利用時(shí)域整形的飛秒激光在電介質(zhì)上加工微流體通道,通過(guò)調(diào)控自由電子密度分布,實(shí)現(xiàn)高效率的微/納加工新方法。首先,提出利用液體輔助飛秒激光脈沖序列的方法在電介質(zhì)材料上加工微通道結(jié)構(gòu),在相同條件下,加工效率提高了56倍,單次掃描加工微通道的極限深徑比提高了3倍。其次,提出了利用飛秒激光脈沖序列輻照改性化學(xué)刻蝕的方法加工微通道結(jié)構(gòu),在相同的條件下,輻照區(qū)域的刻蝕效率提高了10倍;提出了通過(guò)勻減速的掃描方法,改善微通道的截面形狀,實(shí)現(xiàn)了優(yōu)化加工。最后,提出利用飛秒激光脈沖序列的方法消除激光偏振對(duì)輻照改性區(qū)域的影響,實(shí)現(xiàn)各向同性的微通道化學(xué)刻蝕加工。3)首次發(fā)現(xiàn)時(shí)域整形的線偏振飛秒激光在硅材料表面直寫(xiě)加工的各向異性新現(xiàn)象,通過(guò)調(diào)控材料表面等離子體的形成及分布,實(shí)現(xiàn)可控性表面微/納加工新方法。在固定點(diǎn)加工中,通過(guò)改變脈沖序列子脈沖間隔,調(diào)控表面結(jié)構(gòu)的周期及形貌;在激光直寫(xiě)中,首次發(fā)現(xiàn)并提出了線偏振的飛秒激光在硅材料表面直寫(xiě)加工的各向異性現(xiàn)象,提出通過(guò)改變飛秒激光的偏振、掃描方向、掃描速度等參數(shù),調(diào)控表面結(jié)構(gòu)的幾何形貌及方向。
[Abstract]:Femtosecond laser micro / nano manufacturing is a frontier area which includes mechanical, thermodynamic, optical, material and other disciplines. It is widely used in defense, medical, information and so on. Femtosecond laser has ultra high peak power, and its function is a nonlinear, nonequilibrium multiscale process from nanometer to millisecond, from femtosecond to microsecond. It is quite different from the traditional manufacturing mechanism. Therefore, the study of femtosecond laser micro / nanofabrication technology is of great importance to the physics and manufacturing science itself. With the further development of microminiaturization, the requirements for the manufacturing quality are increasing. Therefore, the femtosecond laser micro / nano manufacturing is also facing new challenges, such as higher processing quality. In theory, in the process of interaction between femtosecond laser and material, many classical theories are no longer applicable, and the change of optical and thermodynamic instantaneous (femtosecond) local (nanometer) characteristics is very important. Quantum mechanics is needed to improve its prediction accuracy. In experiment, femtosecond laser Micro / nano machining is a multi parameter process involving wavelengths, waveforms, pulse width and frequency, but the laser wave and pulse width will distort or widen in the process of laser transmission due to the introduction of dispersion, and affect the accuracy and repeatability of the processing. In addition, the surface quality, processing efficiency and controllability of the femtosecond laser processing need to be further improved. Therefore, in view of the above scientific problems, the research group, based on the idea of electronic dynamic regulation, proposes to use the method of femtosecond laser time domain shaping to solve the distortion and broadening of the pulse. By controlling the interaction between the photon and the electron, the local instantaneous optical and thermodynamic properties of the material are controlled, the phase transition of the material is selectively excited and the high quality and high efficiency are realized. A new method of femtosecond laser micro / nano fabrication with higher controllability. This paper mainly studies the time-domain shaping femtosecond laser processing nonmetallic materials (dielectric, polymer and semiconductor) based on electronic dynamic regulation and control. The main contents include: 1) the dispersion model of femtosecond laser propagation in the medium is established with Gauss beam as an example. The theoretical model is established. The effects of the two order dispersion, the three order dispersion on the pulse width and the pulse time domain shape of the femtosecond laser pulse are analyzed and analyzed. The quantum plasma model of the interaction of the femtosecond laser with the dielectric material in the time domain is established. The excited ionization of the free electrons, the heat addition and the change of the instantaneous local optical properties of the material are studied in depth. The two order dispersion and the influence of the three order dispersion on the pulse time domain shape of the femtosecond laser pulse are established. A femtosecond laser micro / nanofabrication optical path system in time domain shaping is built. The effect of time domain shaping femtosecond laser parameters on the size (diameter, depth) and surface quality (recasting, micro crack) of the ablation crater is systematically studied. The relationship between the characteristic size of the two-photon polymerization and the laser irradiation parameters based on the two-photon polymerization is derived, and the use of the.4 is derived. The domain shaping femtosecond laser is polymerized and the limit resolution size.5 of lambda /12 is realized. A new method of high efficiency preparation of microfluidic channel using femtosecond laser in time domain shaping is proposed, and the effect of each parameter on the processing efficiency of microchannel.6) is studied. The orientation and geometry of the periodic structure of the semiconductor material are regulated by regulating the scanning speed, the direction and the direction of polarization of the femtosecond laser. The main achievements in this paper are summarized as follows: 1) the processing of the dielectric by using the femtosecond laser in time domain is proposed, and the electronic excitation and electricity are regulated by the control of electronic excitation. A new method of high precision and high quality micro / nano machining. First, a new phenomenon of ablation enhancement between 100 FS-200 FS is discovered by changing the interval of the pulse sequence. Secondly, the diameter and depth of the ablation structure are regulated by changing the number of subpulses in the pulse sequence. Finally, the energy of the pulse sequence is changed. A new method of micro / nanofabrication is realized by using time domain shaping femtosecond laser to process the microfluidic channel on the dielectric. By adjusting the density distribution of free electrons, a new efficient micro / nanofabrication method is realized by using the time domain shaping femtosecond laser in the dielectric. First, the liquid assisted femtosecond excitation is proposed. The method of optical pulse sequence is used to process microchannel structure on dielectric material. Under the same condition, the machining efficiency is increased by 56 times. The limit depth diameter ratio of the single scanning micro channel is 3 times higher. Secondly, the microchannel structure is processed by using the femtosecond laser pulse sequence to irradiate the modified chemical etching. The etching efficiency of the region is increased by 10 times, and the shape of the microchannel cross section is improved by the uniform deceleration method. Finally, the effect of the laser polarization on the irradiated region is eliminated by the method of the femtosecond laser pulse sequence, and the isotropic microchannel chemical etching process.3 is first discovered. A new anisotropic new phenomenon of linear polarization femtosecond laser processing on the surface of silicon material. By regulating the formation and distribution of the surface plasma of the material, a new method of controllable surface micro / nanofabrication is realized. In the fixed point processing, the periodic and morphology of the surface structure are regulated by changing the pulse interval of the pulse sequence, and the laser is straight. In writing, the isotropic phenomenon of linear polarization of femtosecond laser on the surface of silicon material is discovered and proposed for the first time. The geometric morphology and direction of the surface structure are regulated by changing the polarization, scanning direction and scanning speed of the femtosecond laser.
【學(xué)位授予單位】：北京理工大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類(lèi)號(hào)】：TG665

【參考文獻(xiàn)】

相關(guān)期刊論文 前9條

1 徐傳彩;姜瀾;冷妮;劉鵬軍;;Selective triggering of phase change in dielectrics by femtosecond pulse trains based on electron dynamics control[J];Chinese Physics B;2013年04期

2 徐傳彩;姜瀾;冷妮;袁艷萍;劉鵬軍;王聰;陸永楓;;Ultrafast laser ablation size and recast adjustment in dielectrics based on electron dynamics control by pulse train shaping[J];Chinese Optics Letters;2013年04期

3 蔡海龍;閆雪亮;王素梅;夏博;劉鵬軍;姜瀾;;飛秒激光微通道加工研究進(jìn)展[J];北京理工大學(xué)學(xué)報(bào);2012年10期

4 宋e，

本文編號(hào)：2079697