Film Analysis Employing Subtarget Effect Using 355nm Nd-YAG Laser-Induced Plasma at Low Pressure

The applicability of spectrochemical analysis for liquid and powder samples of minute amount in the form of thin film was investigated using ultraviolet Nd-YAG laser (355 nm) and low-pressure ambient gas. A variety of organic samples such as commercial black ink usually used for stamp pad, gingseng extract, human blood, liquid milk, and gingseng powder was prepared as film deposited on the surface of an appropriate hard substrates such as copper plate or glass slide. It was demonstrated that in all cases studied, good quality spectra were obtained with very low background and free from undesirable contamination by the substrate elements, featuring ppm or even sub-ppm sensitivity and worthy of application for quantitative analysis of organic samples.