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PROCESS AND APPARATUS FOR THE ELEMENTARY AND CHEMICAL ANALYSIS OF A SAMPLE BY SPECTRUM ANALYSIS OFTHE ENERGY OF THE SECONDARY ELECTRONS
PROCESS AND APPARATUS FOR THE ELEMENTARY AND CHEMICAL ANALYSIS OF A SAMPLE BY SPECTRUM ANALYSIS OFTHE ENERGY OF THE SECONDARY ELECTRONS
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机译：通过二次电子能谱分析对样品进行元素和化学分析的方法和装置
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1530277 Electron microscopes COMMISSARIAT A L'ENERGIE ATOMIQUE 14 Oct 1975 [2 Jan 1975 23 May 1975] 42084/75 Heading H1D In the analysis of a sample, the intensity of a beam of mono-energetic primary electrons is modulated sinusoidally at a frequency w, the intensity of the component of frequency w being detected electrically and the value of the energy of collection E changed to scan the energy spectrum between two limits E 1 , Eg so that the spectrum n (E) is obtained as a function of E. Sweeping of the sample surface produces n(E) for each point and a distribution of, for example, Auger transitions. Apparatus, comprises secondary electron energy analyser 58, a detector 59 (e.g. channel electron multiplier type) of the analysed secondary electrons, means such as phase sensitive demodulator 34 for measuring in the detection signal the intensity of the frequency w component, reference voltage generator 56, and a recorder 36. Scanning of the energy is achieved by voltage ramp generator 70. Analyser 58 is preferably a cylindrical coaxial analyser but may be a grid or magnetic analyser. Transitions leading to emissions are discussed and Fig. 4 (not shown) indicates back-scattering of magnitude h 2 , random noise h b and Auger peak h a . Detailed analysis is included with comparisons with the prior art analysers of Figs. 5 and 6 (not shown). Modulation of the primary beam may be 100% of m, + h a (Fig. 4) rather than h 2 -h 1 , the signal noise ratio being improved and the phase sensitive modulator permits weak variation studies at the extremes of the curve n(E). The modulator 34 may be replaced by a bandpass filter, or a real time correlator or a Fourier transformation device. The X-Y recorder 36 may be replaced by an oscilloscope or A/D converter. Sensitivity may be improved by inserting a scintillator with a photomultiplier before the detector or any device receiving component w. The sample may be of Si, Cr or oxygen for example, the gun may be used with an LaB 6 crystal and a field emission gun further improves spatial resolution. The sample may be biological and may be the anode, or a supplementary anode plate may be interposed.
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