Surface Analysis

Surface analysis provides chemical element and bonding information of substance from nanometer scale of surface and near surface for various materials. In addition, depth profiling, elemental image mapping, and micro-area analysis extend the capabilities of many of these techniques.

The Surface laboratory (IMS Room 023) houses several Auger electron spectroscopies (AES), X-ray Photoelectron spectroscopies (XPS) and a secondary ion mass spectroscopy (SIMS).¬†A complete listing of the laboratory’s instrumentation is as follows:


PHI 595 Multiprobe System
phi_multiprobe The PHI Multiprobe includes a 595 Scanning Auger electron spectroscopy (AES), combined with an X-ray photoelectron spectroscopy (XPS), and secondary ion mass spectroscopy (SIMS). The multiple analysis techniques contained within this ultra-high vacuum chamber allow us to analyze most materials. We are using an RBD Instrument interface and software, integrating all analysis techniques into one easy to use software package.The XPS of the Multiprobe possesses an aluminum and magnesium twin x-ray source. A sputtering differential ion gun is equipped for sample surface sputtering, which provides surface cleaning and etching. It also provides a quantitative spectroscopic technique that measures the elemental composition, empirical formula, chemical state and electronic state of the elements that exist within a material. XPS is able to analyze inorganic compounds, metal alloys, semiconductors, polymers, elements, catalysts, glasses, ceramics, paints, papers, inks, woods, plant parts, bio-materials, viscous oils, glues, and many others.The equipped quadruple secondary ion mass spectroscopy (SIMS) of the multirpobe provides the capability to detect various trace elemental isotopes up to ppm level. SIMS is also able to supply elemental isotope depth profile.


PHI Model 590 Scanning Auger Electron Spectroscopy
590_auger In addition to PHI 595 scanning Auger spectroscopy, the laboratory contains a dedicated PHI 590 Auger spectroscopy available to graduate students for research purposes. This system has an argon ion sputter gun and the same software and abilities to produce Auger chemical maps and SED images as the PHI 595 Multiprobe system. The PHI 590 Auger spectroscopy possesses a much high sensitivity than PHI 595 Auger system and is particularly suitable for analyzing elements with low concentration.


VG Scientific X-ray Photoelectron Spectroscopy
vg_escalab_mkii The VG Scientific ESCALAB MKII spectroscopy includes aluminum /magnesium, silver/titanium twin anodes and monochromator X-ray sources. It is equipped with a hemispherical analyzer and an ion sputtering gun for sample cleaning and etching. The ESCALAB MKII offers a sample preparation chamber used for a range of in-situ treatment and sample preparation procedures. The vacuum system, with a turbo molecular pump combined with two ion pumps serving the main chamber, gives the system good sample outgas tolerance which gives the facility a wide capability to analyze drug and polymer samples in addition to ceramics and metals. The ESCALAB MKII XPS presents an excellent analysis capability to problems related to thin film, junction, solder ability, corrosion, discoloration, contamination, cleaning, adhesion, adsorption or surface processing.


Zygo 3-D Optical Scanning Interferometer Profilometer 
Zygo-profilometer The Zygo white light interferometric profilometer offers fast, non-contact, high accuracy, 3D metrology of surface features for a wide variety of samples. The software provides graphic images and high-resolution numerical analysis to characterize the surface structure of materials at magnifications up to 2000X. Maximum vertical range is 20mm with a resolution of 0.1nm. At the lowest magnification (80X) the field of view is 1.7 x 1.3 mm with 1.22 micron lateral resolution (0.67 micron resolution at higher mags) and stitching capabilities allow for mapping of extensive areas. The Zygo system includes an isolation table for high-magnification work and will fit samples up to 4 inches high and 7 inches square. Samples must be somewhat reflective, though materials may be sputter coated with a minimal amount of gold (~100 angstroms) to assist in imaging without substantially changing the topography. Analysis capabilities include histograms, various filters, and masks. Algorithms provide leveling for sample images and can separate Roughness values from overall topography such as cylinders of spheres.