19 research outputs found
Carbon and the Kinetics of Oxygen Precipitation in Silicon
No full textABSTRACTOxygen precipitation in Czochralski silicon has been studied as a function of anneal time, oxygen concentration and carbon concentration using FTIR. It was found that the oxygen supersaturation controls the precipitation kinetics in high oxygen content samples, whereas the carbon concentration is of prime importance in low oxygen content samples. The decrease in sustitutional carbon concentration after nucleation and its subsequent increase with extended growth anneals supports the view that carbon affects precipitate nucleation, but not precipitate growth. The measured oxygen solubility at 1000°C was found to depend on both the initial oxygen concentration and the initial carbon concentration.</jats:p
The Microstructure of Silicon-on-Insulator Structures Formed by High Dose Oxygen Ion Implantation
No full textABSTRACTCross-sectional and plan view transmission electron microscopy and high resolution scanning electron microscopy have been used to characterize the microstructure of silicon-on-insulator formed by high dose oxygen ion implantation. The complete microstructure was observed to be composed of a series of distinct zones. The top silicon layer was {100} single crystal with a very low dislocation density. The second layer was a mixture of fine grained polysilicon and amorphous SiO2. The third layer was pure SiO2 , followed by a second mixed layer. Finally, there was a layer of {100} silicon with an extremely high dislocation density. Some of the dislocations extended as far as 1 μm into the Si substrate. The relative widths of the layers were found to depend on the total ion fluence. The oxide layer did not occur for low doses and the two mixed layers merged into one zone. At high doses, the silicon-silicon dioxide interfaces are abrupt due to internal oxidation.</jats:p
Anisotropic Transport of Impurities in Ion Mixing
No full textABSTRACTExperimental investigations of the redistribution of a thin (1nm) Sn marker layer lying between two thicker dissimilar layers (Ge and Si) during 360 keV As ion irradiation are reported. Several permutations of layer arrangements were tested, i.e. Si/Sn/Ge, Ge/Sn/Si, Si/Sn/Si and Ge/Sn/Ge. It was also found that in the dissimilar “diffusion” couples, the Sn drifts in the Ge rich direction, regardless of whether the Ge is on the surface side or the substrate side of the marker. This phenomemon of anisotropic transport is interpreted as a drift induced by a gradient in the “diffusion” coefficient. The radiation resistance of concentrated alloys is discussed in the light of this phenomenon.</jats:p
Silicon Nanostructures in Si-Based Light-Emithing Devices
No full textAbstractHigh resolution cross-sectional electron microscopy and electron diffraction of an np heterojunction porous Si device, capable of emitting light at visible wavelengths, clearly indicates the presence of Si nanostructures within the quantum size regime. These results indicate that the quantum confinement effect is at least partially responsible for photoluminescence at visible wavelengths.</jats:p
Effect of Oxygen Implantation Conditions on Buried Si0<sub>2</sub> Layer Formation using a Multiple Step Process
No full textABSTRACTWe have studied the effect of implantation temperature, dose step, and total dose on the buried Si02 layer formed with a multiple low dose oxygen implantation process. Furthermore, we have produced a continuous, high quality buried SiO2 layer about 1500 Å thick with a dose of only 7 × 1017 0+/cm2 at 160 keV. The thin SiO2 layer is important not only because of the possible economic advantages of reduced dose, but also because a thinner oxide layer is more radiation hard.</jats:p
MOSFETs Fabricated in {100} single crystal silicon-on-oxide obtained by a laser-induced lateral seeding technique
No full text
