When they are reverse biased they exhibit a very high resistance, and consequently a low value of reverse leakage current. The junction region is covered with a layer of silicon dioxide (SiO 2 ). The layer of SiO2 helps to prevent contamination of the junctions. It specifically acts in the breakdown region in the reverse biased condition. The forward characteristic of the zener diode is similar to a normal diode which is clearly seen in the figure above. The basic construction of the Zener Diode is not different from the simple PN junction diode in a way that both diodes have an N-Region and P-Region and a PN junction. As shown in Fig. When Zener diodes are biased in their forward direction, with the anode voltage higher than the cathode, they behave in the same way as a normal silicon diode. We go over the characteristics & working principle of a Zener Diode. The diode made by connecting a very thin wire (its end is very sharp) on a semiconductor material is known as point contact diode. Thus, is used in the construction of zener diode. To determine … The thickness of this … A zener diode shows two breakdown approach, zener breakdown, and avalanche breakdown. As the reverse voltage approaches the reverse breakdown voltage the electrons and holes entering the depletion layer come under the effect of a strong electric field and are rapidly accelerated. Special techniques are applied in the fabrication of zener diodes to create the required properties. Breakdown voltages can be selected in this way to occur at precise preset values anywhere between about 3V and 300V. Zener diodes can be tested for opens, shorts, or leakage with an ohmmeter. It is majorly used in voltage regulation in order to keep the voltage constant even when the load shows variation. 0. Construction of zener diode. The P type and N type silicon used is doped more heavily than a standard PN diode. … With the increase in reverse potential, a strong electric field is generated by the depletion region. During its movement, minority carriers collide with the atoms and generate more number of free electrons. This rapid increase in reverse current in Zener diode operation is due to one or both of two effects: Because of the heavily doped P and N materials at either side of the junction, which are therefore good conductors, and the very thin depletion layer, the electric field strength across the depletion layer is very strong, and it becomes relatively easy, even at low voltages, for holes and electrons to cross the depletion layer and combine to create a reverse current. Thereby generating free electrons. Most of the diodes are made from silicon because it can afford high temperature, however, germanium is also used for manufacturing where low voltage drop is required. This region is after the reverse-biased … To prevent this current increasing to a value that would exceed the diode´s power rating and destroy it, the Zener diode uses a resistor connected in series with the diode to limit the reverse current to a safe value. At the same time during construction, the whole assembly is metallised in order to generate anode and cathode connection. The Zener diode's operation depends on the heavy doping of its p-n junction. Zener breakdown was first noticed and explained by American Scientist C. Zener. Newest unlock from SMI with identify SMD Zener Diode Marketplace Analysis Document 2019-2026 (by way of Product Sort, Finish-Consumer / Utility and Areas / Nations) supplies an in … Due to the high concentration of impurities, the width of the depletion width is narrow. In this article, let us learn the function of Zener diodes along with its construction, operation and more. 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