The effect of HF etching of the silicon oxide shell covering the surface of Si nanocrystals (NCs) on the subsequent room-temperature atmospheric oxidation of Si-NCs has been investigated by means of photoluminescence measurements, Fourier transform infrared spectroscopy, and electron paramagnetic... (Read more)

Silicon carbide (SiC) has a range of useful physical, mechanical and electronic properties that make it a promising material for next-generation electronic devices^1,2. Careful consideration of the thermal conditions^3-6 in which SiC {0001} is grown has resulted in improvements in crystal diameter and quality: the quantity of macroscopic defects such as hollow core dislocations (micropipes)^7-9, inclusions, small-angle boundaries and longrange lattice warp has been reduced^10,11. But some macroscopic defects (about 1–10 cm^-2) and a large density of elementary dislocations (,10⁴ cm^-2), such as edge, basal plane and screw dislocations, remain within the crystal, and have so far prevented the realization of high-efficiency, reliable electronic devices in SiC (refs 12–16). Here we report a method, inspired by the dislocation structure of SiC grown perpendicular to the c-axis (a-face growth)¹⁷, to reduce the number of dislocations in SiC single crystals by two to three orders of magnitude, rendering them virtually dislocation-free. These substrates will promote the development of high-power SiC devices and reduce energy losses of the resulting electrical systems. (Read more)

The structural degradation of thermal SiO₂ on (100)Si under isochronal vacuum annealing in the range T_an = 950 °C–1250 °C was monitored by electron spin resonance (ESR) in terms of point defect creation, including... (Read more)

Hexagonal voids observed in sublimation grown SiC boules were examined using optical microscopy, atomic force microscopy (AFM), scanning electron microscopy, KOH etching, and synchrotron white-beam x-ray topography. Voids formed at imperfections in the attachment layer between the seed and crucible... (Read more)

GaN community has recently recognized that it is imperative that the extended, and point defects in GaN and related materials, and the mechanisms for their formation are understood. This is a first and an important step, which must be followed by defect reduction before full implementation of this... (Read more)

We show that Cat-CVD silicon nitride films contain more than 1019 cm−3 nitrogen-bonded Si dangling bonds, similarly to the case for conventional CVD films. However, the charge-trapping behavior of the Cat-CVD films is found to be quite different, in spite of the same origin for the dominant... (Read more)

The sublimation epitaxy growth process has been studied. The structural quality of the grown layers improves compared with the substrate mainly due to a diminished domain structure misorientation. Optical microscopy shows that the as-grown surfaces are free of typical defects appearing in silicon... (Read more)

Electron paramagnetic resonance (EPR) measurements of Si/SiO₂ systems began over 30 years ago. Most EPR studies of Si/SiO₂ systems have dealt with two families of defects: P_b centers and E centers. Several variants from each group have... (Read more)

In situ electron-spin-resonance (ESR) measurements of film growth of hydrogenated amorphous silicon (a-Si:H) using a remote hydrogen plasma technique have been performed. The Si dangling-bond signal in a-Si:H during and after deposition has been detected, in addition to the... (Read more)

Three kinds of paramagnetic centers named P_A, P_B and P_C have been found in a silicon-silicon dioxide structure at liquid nitrogen temperature. P_A (g=∼2.000, ΔH=∼4 Oe), and P_B having anisotropic g-value... (Read more)

The solubilities of substitutional and interstitial copper (Cu^s and Cuⁱ) have been measured in intrinsic and extrinsic n- and p-type Ge, Si, and GaAs, using Cu⁶⁴. These measurements show that Cu^s is a triple acceptor in... (Read more)

Etching and copper decoration techniques have shown that silicon crystals grown from quartz crucibles under proper conditions contain no detectable dislocations.However,oxygen in concentration up to about 10¹⁸ per cm³incorporated from the quartz crucible might conceivably... (Read more)