發(fā)布時(shí)間：2018-08-17 11:53

【摘要】：激光誘導(dǎo)擊穿光譜(Laser induced breakdown spectroscopy,LIBS)技術(shù),是一種利用聚焦后的脈沖激光燒蝕樣品,產(chǎn)生瞬態(tài)高溫等離子體,通過(guò)測(cè)量等離子體冷卻時(shí)發(fā)射的原子或離子光譜來(lái)實(shí)現(xiàn)樣品成分分析的技術(shù)。自其誕生以來(lái),LIBS技術(shù)憑借其實(shí)時(shí)、快速、可遠(yuǎn)程非接觸測(cè)量,免樣品處理,微量燒蝕,探測(cè)范圍寬,可現(xiàn)場(chǎng)應(yīng)用等優(yōu)點(diǎn)得到快速發(fā)展,在各個(gè)領(lǐng)域得到廣泛應(yīng)用。但將LIBS技術(shù)應(yīng)用于納米薄膜質(zhì)量檢測(cè)時(shí),有很多關(guān)鍵問(wèn)題亟需解決。本文針對(duì)納米薄膜質(zhì)量分析中的實(shí)際應(yīng)用需求,將LIBS分析技術(shù)與薄膜分析技術(shù)結(jié)合,對(duì)結(jié)合過(guò)程中存在的關(guān)鍵科學(xué)問(wèn)題和技術(shù)問(wèn)題進(jìn)行了深入的研究。文章從分析系統(tǒng)的設(shè)計(jì)實(shí)現(xiàn),各種參數(shù)的影響,等離子體特性的多角度分析和系統(tǒng)的檢測(cè)能力等幾個(gè)方面進(jìn)行了研究和討論。針對(duì)納米材料本身的結(jié)構(gòu)特性和LIBS技術(shù)的燒蝕特點(diǎn),本文設(shè)計(jì)實(shí)現(xiàn)了一套利用定位系統(tǒng)輔助定位的LIBS薄膜綜合分析系統(tǒng)。利用該系統(tǒng),本文針對(duì)LIBS檢測(cè)的重復(fù)性進(jìn)行了實(shí)驗(yàn)研究,并計(jì)算了強(qiáng)度的相對(duì)標(biāo)準(zhǔn)偏差(RSD),結(jié)果小于2%,證明了所搭建的系統(tǒng)具有較好的重復(fù)性和穩(wěn)定性,可用于納米薄膜質(zhì)量分析。同時(shí),還根據(jù)實(shí)際測(cè)試的結(jié)果,完善了激發(fā)和收集光路的設(shè)計(jì)。本文利用搭建的系統(tǒng),深入分析了各種不同實(shí)驗(yàn)參數(shù)(激光能量、激光聚焦點(diǎn)到樣品表面距離(LFTSD)參數(shù)、聚焦條件、收集光路等)對(duì)等離子體演化和光譜輻射特性的影響。實(shí)驗(yàn)數(shù)據(jù)表明,LFTSD參數(shù)是影響激光-物質(zhì)相互作用過(guò)程、等離子體形態(tài)以及等離子體光譜發(fā)射等過(guò)程的主要因素之一。在低能量(1 mJ),LFTSD=0處獲得了一系列硅元素的譜線,并利用這些譜線計(jì)算了電子溫度(17445 K),同時(shí)利用硅的兩條譜線(250.69 nm和252.85nm)和Hα線計(jì)算了電子密度(1.66×1017cm-3、1.47×1017cm-3和7.5×1017cm-3),驗(yàn)證了產(chǎn)生的等離子體滿足局部熱力學(xué)(LTE)條件。針對(duì)實(shí)驗(yàn)中和分析中遇到的一些問(wèn)題,本文對(duì)搭建的系統(tǒng)進(jìn)行了改進(jìn)和完善,采用位置靈敏傳感器(PSD)定位單元和等離子體時(shí)空分辨分析單元,對(duì)關(guān)鍵的LFTSD參數(shù)和等離子體診斷光路進(jìn)行了優(yōu)化。利用新系統(tǒng)和新制備的樣品,驗(yàn)證了系統(tǒng)的穩(wěn)定性(光譜強(qiáng)度RSD小于1.5%),并研究了利用硅元素校正前后譜線強(qiáng)度與樣品組分間的關(guān)系。結(jié)果表明,經(jīng)校正后,譜線強(qiáng)度與薄膜組分濃度間呈較好的線性關(guān)系(90%以上)。最后,對(duì)全文內(nèi)容進(jìn)行了總結(jié),分析了本文工作的創(chuàng)新點(diǎn)。根據(jù)實(shí)際應(yīng)用需求,對(duì)下一步的研究?jī)?nèi)容進(jìn)行了展望。
[Abstract]:Laser induced breakdown spectroscopy (Laser induced breakdown spectroscope) technique is a kind of transient high temperature plasma produced by pulsed laser ablation of samples after focusing. A technique for sample composition analysis by measuring the atomic or ionic spectra emitted by a plasma during cooling. Since its birth, LIBS technology has been rapidly developed with its advantages of real-time, fast, remote non-contact measurement, sample free treatment, micro-ablation, wide detection range, and can be applied in various fields. However, there are many key problems to be solved when LIBS technology is applied to the quality detection of nanocrystalline films. In this paper, the key scientific and technical problems existing in the process of nano-film quality analysis are deeply studied by combining the LIBS analysis technology with the thin film analysis technology in order to meet the practical application needs in the analysis of the quality of nanocrystalline films. The design and implementation of the analysis system, the influence of various parameters, the multi-angle analysis of plasma characteristics and the detection ability of the system are studied and discussed in this paper. According to the structural characteristics of nanomaterials and the ablative characteristics of LIBS technology, a comprehensive analysis system for LIBS thin films is designed and implemented by using positioning system. By using this system, the repeatability of LIBS detection is studied experimentally, and the relative standard deviation (RSD),) results of strength are calculated. It is proved that the system has good repeatability and stability. It can be used to analyze the quality of nanometer film. At the same time, according to the actual test results, the design of excitation and collection light path is improved. In this paper, the effects of various experimental parameters (laser energy, laser focus distance to surface (LFTSD) parameter, focusing condition, collection path, etc.) on plasma evolution and spectral radiation characteristics are analyzed. The experimental data show that the parameters of LFTSD are one of the main factors affecting the laser-matter interaction, plasma morphology and plasma spectral emission. At the low energy (1 MJ) LFT SD0, a series of Si spectral lines have been obtained. The electron temperature (17445 K),) and the electron densities (1.66 脳 1017cm-347 脳 1017cm-3 and 7.5 脳 1017cm-3) of silicon (250.69 nm and 252.85nm) and H 偽 (1.66 脳 1017cm-347 脳 1017cm-3 and 7.5 脳 1017cm-3) have been calculated simultaneously. It is verified that the produced plasma satisfies the local thermodynamic (LTE) condition. Aiming at some problems encountered in the experiment and analysis, the system is improved and perfected in this paper. The position sensitive sensor (PSD) positioning unit and the plasma space-time resolution analysis unit are used. The key parameters of LFTSD and the optical path of plasma diagnosis are optimized. The stability of the system (the spectral intensity RSD is less than 1.5%) was verified by using the new system and the newly prepared samples. The relationship between the spectral line strength and the composition of the sample before and after correction with the silicon element was studied. The results show that there is a good linear relationship between the spectral line strength and the composition concentration of the film (more than 90%). Finally, the content of this paper is summarized, and the innovation of this paper is analyzed. According to the practical application requirements, the future research content is prospected.
【學(xué)位授予單位】：青島大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB383

【共引文獻(xiàn)】

相關(guān)期刊論文 前10條

1 馬靖,陸同興;振鈴光譜技術(shù)中腔內(nèi)光場(chǎng)的漲落計(jì)算[J];安徽師范大學(xué)學(xué)報(bào)(自然科學(xué)版);2001年03期

2 唐曉閂,楊銳,鄭賢鋒,鳳爾銀,馬靖,季學(xué)韓,崔執(zhí)鳳;激光燒蝕鋁等離子體中離子特性的實(shí)驗(yàn)研究[J];安徽師范大學(xué)學(xué)報(bào)(自然科學(xué)版);2002年02期

3 李慧敏;傅院霞;張先q，

本文編號(hào)：2187550