Radio-Frequency Glow-Discharge Mass Spectrometry for Direct Analysis of Sintered Ceramics

为了将射频辉光放电（RF-GD）应用于非导电材料的分析，构建了grimm型原子发射源和质谱源。测定了烧结陶瓷（氧化铝、氧化锆和氮化硅）在不同操作条件下的原子发射光谱和质谱。分析物信号强度受射频功率和气体压力等参数的影响。此外，样品厚度对光谱也有影响；ie。，信号强度随厚度的增加而减小。RF-GD源原子发射光谱法的灵敏度低于质谱法。通过用水充分冷却放电源体，可以在不降低放电稳定性的情况下将射频功率提高到150W。因此，分析物信号强度增加，灵敏度可以提高。研究了自偏置电压和溅射速率等特性。用grimm型RF-GD源获得的陨石坑剖面一般呈凸形。使用直流（DC）的GD发射光谱法的各种努力旨在获得一个平底陨石坑，以获得更好的深度分辨率。在本研究中，我们没有使用射频而是使用直流来研究影响陨石坑形状的参数，以便与其他地方获得的几种DC- gd发射光谱结果进行比较。结果表明，阳极内径对形成平底弹坑有重要影响。然而，需要进一步的研究将我们的结果应用于RF-GD发射和质谱分析。

In order to apply radio-frequency glow discharge(RF-GD)to analysis of nonconducting materials, Grimm-type sources were constructed for atomic emission and mass spectrometry. Atomic emission and mass spectra of sintered ceramics (alumina, zirconia and silicon nitride) were measured under various operating conditions. Analyte signal intensities were affected by parameters such as RF power and gas pressure. In addition, sample thickness also affected the spectra ; ie., signal intensities decreased with increasing the thickness.The sensitivity of atomic emission spectrometry with the RF-GD source, however, was lower than that of mass spectrometry. By cooling sufficiently the body of the discharge source with water, it was possible to increase the RF power to 150W without deteriorating the discharge stability. Consequently, analyte signal intensities increased and the sensitivity could be improved. Several characteristics such as a self bias voltage and sputtering rate were also studied.Crater profiles obtained with the Grimm-type RF-GD source generally had a convex shape. Various efforts in GD emission spectrometry using a direct current(DC) have been aimed at achieving a flat bottom crater for better depth resolution. In this study, the parameters that affect the crater shape were studied not using RF but DC in order to compare with several results of DC-GD emission spectrometry obtained elsewhere. It was found that the inner diameter of the anode has significant effect in producing a flat bottom crater. Further investigations, however, are required to apply our reaults to RF-GD emission and mass spectrometry.