| Researching the non-uniform channel DMOS is the basic knowledge of the new generation high voltage power MOS devices and the important domain of the IC —— smart power ICs. This dissertation investigates the basic parameters and the radiation theory of non-uniform channel DMOS. The threshold voltage model of micron and deep sub-micron non-uniform channel DMOS, the radiation threshold voltage model, the radiation mobility model and the transient response model of single ion radiation are internationally proposed for the first time. Theory study and model constitution would establish foundation of the next generation power devices and power circuits. The author's main contributions are outlined as following: The 2-D threshold voltage models of non-uniform channel DMOS is proposed. The model includes the micron and deep sub-micron non-uniform channel DMOS. Based on the 2-D distribution of channel impurity, Resolved the Poisson equation, the channel depletion width is obtained. So the channel depletion charge is calculated and the mathematics expression of the micron level threshold voltage model is obtained. The non-uniform channel impurity, the non-equal surface potential for the changing of balance energy band and the gate capacitor by the edge effect is thought about; the mathematics expression of the deep sub-micron non-uniform channel DMOS threshold voltage model is obtained. The results of the threshold voltage model agree well with those of the experiment, and those of the 2-D simulator MEDICI. The simplified expression of DMOS threshold voltage is given with the channel surface diffusion concentration changing from 2.0×1016cm-3 to 10.0×1016cm-3. The radiation mobility shift model and threshold voltage model of the non-uniform channel DMOS are proposed. The interface state model related with the "Hydrogen Ion Transport" is proposed. The producing process of the interface state at the total ion dose is primely analyzed using the interface state model. Based on the 2-D distribution of channel impurity, the distribution of 2-D electric field and 2-D interaction potential, which is caused by the interaction between the ionized impurity in the depletion layer and radiation induced positive spatial charge, is analyzed by using image charge method. Resolving Poisson equation, the mobility expression of N-type and P-type non-uniform channel MOS and the mathematics expression of the threshold voltage model of DMOS are obtained. The results of the models agree well with those of the 2-D simulator MEDICI. Uniform channel MOS's mobility and threshold voltage shift values agree with that of the experiment in the files. The transient response model of single ion radiate the non-uniform channel DMOS is proposed. Based on the transport mechanism of the single ion radiate plasma, the transient response characters of DMOS at non-junction, single junction and double junction are obtained by the transient response numerical analysis result of the open and close state of the DMOS at different energy ion radiation. Indicated that the peak value drain current of the on state is bigger than that of the off state, the peak value drain current and the arisen time of the peak value drain current are increased while the energy of the ion is increased. The critical energy of the single ion radiation is taken out. The mathematics expression of the critical energy is obtained. Based on these models, the power conversion characters of non-uniform channel DMOS is researched in experiments. The process of DMOS's electrify transient character is divided to three parts. First, the insulator layer capacitor is charged. Accumulated state of the sub-layer is changed to depleted state, the depletion capacitor is not formed and the current of the sub-layer is increasing until the depletion capacitor is forming, when the depletion capacitor affects the total capacitor, is increased to the peak value. Second, the parasitical capacitor is becoming small while the total capacitor is discharged for the depletion width is increasing,...
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