Semiconductors Auger electron spectroscopy

GD-OES (glow discharge optical emission spectrometry) are applied. AES (auger electron spectroscopy), AFM (atomic force microscopy) and TRXF (transmission reflection X-ray fluorescence analysis) have been successfully used, especially in the semiconductor industry and in materials research. 

As a surface analytical tool, SIMS has several advantages over X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). SIMS is sensitive to all elements and isotopes in the periodic table, whereas XPS and AES cannot detect H and He. SIMS also has a lower detection limit of 10 5 atomic percent (at.S) compared to 0.1 at.S and 1.0 at.% for AES and XPS, respectively. However, SIMS has several disadvantages. Its elemental sensitivity varies over five orders of magnitude and differs for a given element in different sample matrices, i.e., SIMS shows a strong matrix effect. This matrix effect makes SIMS measurements difficult to quantify. Recent progress, however, has been made especially in the development of quantitative models for the analysis of semiconductors [3-5]. 

AES Auger Electron Spectroscopy Electrons Quantitative elemental analysis tool for determining surface composition of semiconductors and conductors. Limited to non-insulators. 

In recent development of the semiconductor industries, thermal oxide film thickness of less than 5 nm has been used in semiconductor devices such as metal-oxide-semiconductor (MOS) structures. Thickness of less than 5 nm is almost near the thickness of a native oxide film on the surface of silicon wafer. Therefore the characterization of ultra thin native oxide film is important in the semiconductor process technology. The secondary electron microscopy (SEM), the scanning Auger electron microscopy (SAM), the atomic force microscopy (AFM) and the X-ray photoelectron spectroscopy (XPS) might be the useful characterization method for the surface of the silicon wafers. 

A related technique is Auger emission spectroscopy (AES). Here, the surface is bombarded by a beam of electrons of known energy (20 eV-2 keV). The bombardment ejects an electron, whose collision with neighbors emits a photon, which finally causes ejection of yet another electron, referred to as an Auger electron. Usually K- and L-shell electrons are involved. The technique is very useful with heavy elements, and could be used to identify Pb, As, Ba, among others, on composite surfaces (as it is now used with semiconductor surfaces). AES can penetrate to no more than 50 A (5 nm). Suitable equipment is supplied by, among others, JEOL. 

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