In RBS a high-energy (MeV) ion beam bombards the sample surface interacting elastically and inelastically with the sample material.  The elastic collisions provide you with chemical information, i.e. the atomic number (Z) of the sample material and the inelastic collisions provide information about scattering depth.  Thus you obtain elemental composition and material thickness with this non-destructive, standardless analysis.

RBS can be used to look at structural differences in single crystal materials.  Also known as channeling, this is accomplished by directing the incident ion beam down a major crystallographic direction.  Ion interactions along these channels are greatly reduced over ions moving randomly through the lattice.  An atom displaced from a lattice space to an interstitial space will interact strongly with an incident ion making this a good technique to measure lattice defects and strain, as well as interstitial and substitutional impurities.

Some specific applications of RBS are: 

1. Evaluation of the thickness and composition (stoichiometry) of thin films or coatings such as oxide, nitrides or thin-film metals on substrates.

2. Intermixing at the interface between dissimilar materials.

3.Impurity analysis, i.e. concentration as a function of depth.

4. Location of lattice impurities, both substitution and interstitial, within single crystal materials.

5. Determination of damage distribution within a single crystal.  For example, the distribution of implantation damage including the thickness of an ion- induced amorphous layer.

6.Determination of surface reconstruction.

Fig.1: RBS spectrum of Cr (15.4 µg/cm²) on vitreous carbon (VC). RBS was done using ⁴He⁺ beam with the incident energy of 1.5 MeV. The leading edges of each RBS peak are marked with arrows.The thickness of the Cr layer can be determined based on the width of the peak.

Dr. Gazda currently serves as Section Manager at Cerium Labs and is one of our lead scientists.  He is responsible for operations of analytical equipment providing nano-scale metrology and analysis to support Cerium’s extensive customer base.  Dr. Gazda is also acting as a Project Manager and Principal Investigator on Cerium’s collaborations on plurality of SBIR and STTR grant proposals. Under his guidance, Cerium Labs successfully completed a NAVAIR Phase-II work and has received funding for Phase-I activities from the Office of Secretary of Defense.

Dr. Gazda joined AMD Inc., Cerium’s former parent company, in December of 1998. He supported the manufacturing efforts in three AMD Fabs worldwide as TEM analyst and since 2001 as a group leader. During his tenure, he participated in the introduction of the first 1 GHz microprocessor, semiconductor manufacturing technology transitions from 0.25um to 45nm transistor nodes, and participated in R&D efforts to develop advanced transistor/memory cell designs and interconnects structures for AMD and then Spansion devices.  Dr. Gazda has been awarded two US patents and holds one pending USPTO application.

Dr. Gazda obtained his Bachelor of Science degree in Engineering Physics and M. S. in Metallurgy from the University of Illinois at Chicago. He earned his Ph.D. in Materials Science and Engineering at Northwestern University in 1999. Prior to AMD, Dr. Gazda worked for over 8 years at Argonne National Laboratory developing low-activation structural alloys for nuclear industry applications.