We implanted <100> silicon 200mm wafers with 20keV 11B+ to a fluence of 5×1015 atoms/ cm2 using beam currents from 1-7mA, which produced flux of about 50-350µA/cm2. The implant temperature of all wafers rose no more than five degrees above room temperature, regardless of flux. Cross sectional TEM images (as-implanted) of the highest flux samples revealed a continuous amorphous layer from the implanted surface to a depth of about 530Å. The high flux and <30°C implantation temperature allowed amorphous layer formation even with this moderate boron fluence, as was suggested by Jones, et.al.1. We observed a strong dependence of as-implanted damage on boron flux, as previously reported by Eisen and Welch2. After 900°C, 20 sec RTA, the highest flux samples had 50% lower sheet resistance than the lowest flux samples, due to better activation, as observed in SRP. When a 1050°C, 15 sec RTA was employed, this sheet resistance and activation dependence on flux disappeared. Cross sectional TEM images revealed that the size and number of the Type II end of range defects , which were centered near the amorphous and crystalline as-implanted interface, in the highest flux samples were smaller than the Type 1 dislocation loops centered about the peak disorder in the lowest flux samples after RTA. SIMS and SRP profiles indicated that transient enhanced diffusion during the 900°C, 20 sec RTA may have been reduced in the highest flux samples. Based on these observations and on previous reports, we conclude that sufficiently high flux during room temperature boron implantation will produce a continuous amorphous layer with doses that are appropriate for p-type source/drain formation. The amorphous layer will produce improved activation and damage annealing behavior in subsequent RTA, particularly as the RTA temperature is reduced.

No abstract

The film properties of single layers of Ti and TiN and bilayer Ti/TiN film stacks sputtered with and without a collimator on SiO 2 substrates were studied and compared by Rutherford backscattering spectrometry, Auger electron spectroscopy, x-ray diffractometry with both glancing angle and -2 coupled diffraction techniques, scanning electron microscopy, transmission electron microscopy of both cross section and plan view, and atomic force microscopy. The properties investigated include color, stoichiometry, density, electrical resistivity, grain and grain boundary structure, preferred orientation ͑texture͒, stress, surface morphology ͑roughness͒, reflectance, and impurity level. It was found that the density was higher, the surface morphology was less rough, and the electrical resistivity was lower for the collimated films than for the uncollimated films. The lower density and rougher surface of the uncollimated films are caused by shadowing effects.

No abstract

Isolated silicon epitaxy (ISE) is a proven method of producing single crystalline silicon-on-insulator (SOI) material with excellent electrical properties. The presence of the remaining isolated dislocation trails in the epitaxial silicon has led to this investigation of the crystallinity throughout the ISE SOI layer and across the isolated dislocations. The structural perfection of these layers has been examined by defect etching, Nomarski optical microscopy, electron channeling patterns, and with more sensitivity using double crystal synchrotron X-ray diffraction and topography. Defect etching reveals the dislocation density within the layers of production ISE SOI material to be ~5×l0 5 /cm2. Electron channeling pattern techniques have reached the resolution limit of angular orientation resolution for the isolated silicon layer. Finally, synchrotron studies have shown that orientation homogeneity across 5" wafers are preserved to 0.006° and the variation in orientation across the defect trails to be, in general, less than 10 arcsec (0.003°), indicating single crystalline ISE SOI production material.