of thin film analysis is of BaBiKO. This type of film showed superconductivity at one of the highest-temperatures for oxide superconductors. Elemental analysis, shown in figure 9, of this film was carried out using heavy ion-ERDA. These elemental constituents of the polymer film (Bi, K, Mg, O, along with carbon contamination) were detected using an ionization chamber. Other than Potassium, the lighter elements are clearly separated in the matrix. From the matrix, there is evidence of a strong carbon contamination within the film. Some films showed a 1:1 ratio of K to carbon contamination. For this specific film analysis, the source for contamination was traced to an oil diffusion pump and replaced with an oil-free pumping system. ERDA and position resolution In the above examples, the main focus was identification of constituent particles found in thin films and depth resolution was of less significance. Depth resolution is of great importance in applications when a profile of a sample's elemental composition, in different sample layers, has to be measured. This is a powerful tool for materials characterization. Being able to quantify elemental concentration in sub-surface layers can provide a great deal of information pertaining to chemical properties. High sensitivity, i.e. large detector solid angle, can be combined with high depth resolution only if the related kinematic energy shift is compensated. Physical Processes of Elastic Recoil Detection Analysis The Basic chemistry of Forward recoil scattering process is considered to be charged particle interaction with matters. To Understand Forward recoil spectrometry we should know the physics involved in Elastic and Inelastic collisions. In Elastic collision only Kinetic Energy is conserved in the scattering process and there is no role of particle internal energy. Where as in case of Inelastic collision both kinetic energy and internal energy are participated in the scattering process. Physical concepts of two-body elastic scattering are the basis of several nuclear methods for elemental material characterization. Fundamentals of Recoil (Back Scattering) Spectrometry The Fundamental aspects in dealing with recoil spectroscopy involves electron back scattering process of matter such as thin films and solid materials. Energy loss of particles in target materials is evaluated by assuming that the target sample is laterally uniform and constituted by a mono isotopic element. This allows a simple relationship between that of penetration depth profile and elastic scattering yield Main assumptions in physical concepts of Back scattering spectrometry Elastic collision between two bodies is the