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Based on the quantum confinement-luminescence center model, to ensembles of spherical silicon nanocrystals (nc-Si) containing two kinds of luminescence centers (LCs) in the SiOinfinity layers surrounding the nc-Si, the relationship between the photoluminescence (PL) and the thickness of the SiOinfinity layer is studied with the excitation energy flux density as a parameter. When there is no SiOinfinity layer surrounding the nc-Si, the electron-heavy hole pair can only recombine inside the nc-Si, then the PL blueshift with reducing particle sizes roughly accords with the rule predicted by the quantum confinement model of Canham. When there presences a SiOinfinity layer, some of the carriers may tunnel into it and recombine outside the nc-Si at the LCs to emit visible light. The thicker the SiOinfinity layer is, the higher the radiative recombination rate occurred outside the nc-Si will be. When the central scale of the nc-Si is much smaller than the critical scale, the radiative recombination rate outside the nc-Si dominates, and visible PL will be possible for some nc-Si samples with big average radius, greater than 4 nm, for example. When there is only one kind of LC in, the SiOinfinity layer, the PL peak position does not shift with reducing particle sizes. All these conclusions are in accord with the experimental results. When there are two or more kinds of LCs in the SiOinfinity layer, the PL peak position energy and intensity swing with reducing particle sizes.

The annealing temperature (280–810 C) dependences of the concentration profiles of the majority carriers (electrons), the main deep level at EC−400 mV, and the implanted boron ions are reported in 0.23 Ω cm (3.1×1016 cm−3) phosphorus‐doped n‐type silicon which was implanted with 5.0×1011 cm−2 of 200 KeV boron ions. A new constant‐capacitance voltage transient (CCVT) method and a new many‐deep‐level CCVT theory are employed to obtain the deep level profiles whose concentrations are comparable to that of the phosphorus dopant impurity. The measured profile of the implanted boron ions, activated at 810 C, agrees with the projected range theory. Seven peaks are observed above 77 K in the deep‐level capacitance transient spectra. The major peak at EC−400 mV has a concentration profile that lags behind the boron ion profile and it anneals rapidly between 420 and 430 C. The broadness and the annealing behavior of the majority carrier concentration profiles suggest the presence of at least two high‐concentration ...

A general theory is developed to obtain the spatial variations of the concentrations of the deep levels and free carrier from constant-capacitance voltage-transient (CCVT) measurements on semiconductor junctions containing many deep energy levels. In order to measure the deep-level densities near the junction boundary, two methods of edge region correction are also analyzed: the integral equation method and an experimental three-frequency capacitance-voltage method. Conditions under which these methods are easily applicable in experiments are discussed. Applications of these methods are published elsewhere.

Wafers of float zone Si grown in hydrogen (Si[H]) were annealed at various temperatures in the range of 300–750 °C before irradiation with 5 MeV electrons. It was found that hydrogen‐related deep levels were no longer observed, when the preannealing temperature was above 500 °C (450 °C) in the case of irradiated n‐type Si[H] (p‐type Si[H]) samples. Similarly, the convergence of annealing temperatures of different irradiation defects towards a common temperature normally observed in Si[H] was no longer observed, if the Si[H] sample had been annealed at or above 550 °C. A dynamic model is proposed to explain the experimental results.