Design,Simulation,and analysis of novel Double-metal Schottky Diodes.
| Autor: | Chih Hsien Chuang, 莊智賢 |
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| Rok vydání: | 1999 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 87 Schottky barrier diode (SBD) is known as a high-speed and low-forward voltage drop device. In this thesis, a nove l double-metal Schottky diode structure is proposed. Ohmic contact and Schottky contact are both employed to realize the Schottky diode with the lowest power loss by controlling the Schottky barrier height. In general, the trade-off between the forward voltage drop and the reverse blocking property is inevitably encountered in the design of conventional SBD. In addition, the realization of an optimum Schottky barrier height for SBD with minimum power loss must retain both the lowest forward voltage and the lowest reverse saturate current, but it is very difficult in conventional one-metal Schottky diode, because the effective Schottky barrier height of SBD can not be well controlled. But the double-metal Si Schottky diode structure arrive this target. A novel double-metal schottky barrier diode having ohmic and Schottky contact structure based on Si epi-wafers was recently proposed by our laboratory for solving the above-mentioned trade-off problem. The forward voltage decrease because the forwad current is through ohmic contact and the reverse current decrease when the Schottky contact result in the depletion region to generate pinch-off phenomenon. An up front modeling study, two-dimension device simulation program MEDICI and TSUPREM4 will be used to calculate the maximum width of the low barrier height metal still can be fully shielded by the depletion region of the high-barrier-height metal. But from the results show, the two target can not realize in a planar two-metal Schottky diode. So we propound the trench double-meal structure. By suitable adjusting the area ratio and the etch depth, the optimum value of the Schottky barrier for minimum power loss SBDs can be easily realized. We also find the optimum parameter containing etch depth, epitaxial concentration and epitaxial thickness for this structure from the simulated result and the Response Surface Modeling. On the side, we also propound the similar structure that is the doping double-metal Schottky barrier diode. From the simulation, we can find this structure and also can decrease the power loss. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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