DEFECT MODEL OF PHOTOCONVERSION BY OXYGEN IN SEMIINSULATING GAAS

The basic idea of a defect model of photoconversion by an oxygen impurity in semi-insulating GaAs, proposed in an earlier paper, is described in a systematic way. All experiments related to this defect, including high-resolution spectroscopic measurements, piezospectroscopic study, and recent measurements on electronic energy levels, are explained on the basis of this defect model. The predictions of the model are in good agreement with the experiments. A special negative-U mechanism in this defect is discussed in detail with an emphasis on the stability of the charge states. The theoretical basis of using a self-consistent bond-orbital model in the calculation is also given.

Quasi-Thermodynamic Model of MOVPE of InAlN

国家自然科学基金

A Quasi-Therm odynam ic Model of MOVPE of InGaN

国家863计划,国家自然科学基金

Biomimetic (topological) pattern recognition - A new model of pattern recognition theory and its application

A new theoretical model of Pattern Recognition principles was proposed, which is based on "matter cognition" instead of "matter classification" in traditional statistical Pattern Recognition. This new model is closer to the function of human being, rather than traditional statistical Pattern Recognition using "optimal separating" as its main principle. So the new model of Pattern Recognition is called the Biomimetic Pattern Recognition (BPR)(1). Its mathematical basis is placed on topological analysis of the sample set in the high dimensional feature space. Therefore, it is also called the Topological Pattern Recognition (TPR). The fundamental idea of this model is based on the fact of the continuity in the feature space of any one of the certain kinds of samples. We experimented with the Biomimetic Pattern Recognition (BPR) by using artificial neural networks, which act through covering the high dimensional geometrical distribution of the sample set in the feature space. Onmidirectionally cognitive tests were done on various kinds of animal and vehicle models of rather similar shapes. For the total 8800 tests, the correct recognition rate is 99.87%. The rejection rate is 0.13% and on the condition of zero error rates, the correct rate of BPR was much better than that of RBF-SVM.

Small signal equivalent circuit model of vertical cavity surface emitting lasers

Small signal equivalent circuit model of vertical cavity surface emitting lasers (VCSEL's) is given in this paper. The modulation properties of VCSEL are simulated using this model in Pspice program. The simulation results are good agree with experiment data. Experiment is performed to testify the circuit model.

A model of dislocations at the interface of the bonded wafers

Wafer bonding is regardless of lattice mismatch in the integration of dissimilar semiconductor materials. This technology differs from the heteroepitaxy mainly in the mechanism of generating dislocations at the interface. A model of dislocations at the bonded interface is proposed in this paper. Edge-like dislocations, which most efficiently relax the strain, are predominant at the bonded interface. But the thermal stress associated with large thermal expansion misfit may drive dislocations away from the bonded interface upon cooling.

the trustworthiness metric model of software process quality based-on life circle

Communication University of China; Wuhan University; James Madison University; Institute of Policy and Management, Chinese Academy of Sciences; IEEE Wuhan Section