the instrumentation as well as its applications in elemental characterization and depth profile are provided. ERDA and RBS have similar theory but minor differences in the set-up of the experiment. In case of RBS, the detector is placed in the back of the sample whereas in ERDA, the detector is placed in the front. Comparative Analysis There are several techniques used today for characterization of materials. Combination of techniques is usually needed in order to obtain correct characterization. When comparing several techniques, important parameters like detection limit, depth resolution and lateral resolution must be taken into account. For this purpose, comparisons of several techniques have been shown in the table below. Table 1: Comparison of techniques with characteristic properties Characteristics of ERDA The main characteristics of ERDA are listed below. A variety of elements can be analyzed simultaneously as long as the atomic number of recoiled ion is smaller than the atomic number of the primary ion. The sensitivity of this technique, primarily depending upon scattering cross-section area, and the method has almost equal sensitivity to all light elements. In this case the light element is any element which has atomic number between 2 and 50. Depth resolution is depended upon stopping power of heavy ions after interactions with sample, and the detection of scattered primary ions is reduced due to the narrow scattering cone of heavy ions scattering from light elements. Gas-ionization detector provides efficient recoil detection and thus minimizes the exposure of sample to the ion beam making this a non-destructive technique. This is important for accurate measurement of hydrogen which is known for its instability and its loss under ion beam irradiation. Such characteristics have led to many groups and scientists to explore applications of ERDA. History ERDA was first demonstrated by L’Ecuyer et al. in 1976. They had used 25-40 MeV 35Cl ions were used to detect the recoils in the sample. After more than three decades, ERDA has been divided into two main groups. First is the Light incident Ion ERDA (LI-ERDA) and the second is the Heavy incident Ion ERDA (HI-ERDA). LI-ERDA uses low voltage single-ended accelerators, whereas the HI-ERDA uses large tandem accelerators. These techniques were mainly developed after heavy ion accelerators were introduced in the materials research. LI-ERDA is also often performed using a relatively low energy (2 MeV) 4He beam specifically to depth profile hydrogen. In this technique, multiple detectors are