If the voltage across the conductor is heavily increasing, the tunnel current drops down to zero. Hence silicon is not used for fabricating the tunnel diode. Using this approach for the fabrication process, the heavily doped n+ substrate is masked off by an insulating layer to leave a small area exposed. Die Tunneldiode ist eine Erfindung des Japaners Esaki. Esaki. Planar tunnel diode structure: Planar technology can be used to create tunnel diodes. The curve tracer circuit shown in Figure 7.3 and pictured in 7.4 covers a range of units from a fraction of one milliampere to 22 ma. The equivalent circuit of the tunnel diode is expressed in the figure below. The materials used for this diode are Germanium, Gallium arsenide and other silicon materials. The first series of tunnel diodes were formed by the alloying method. The junction region is covered with a layer of silicon dioxide (SiO 2). The current in a diode reached their maximum value IP when the Vp voltage applied across it. It is a fast switching device; thereby it is used in high-frequency oscillators, computers and amplifiers. These all have small forbidden energy gaps and high ion motilities. Tunnel diodes are usually fabricated from germanium, gallium or gallium arsenide. The doping density of the tunnel diode is 1000 times higher than that of the ordinary diode. A low series resistance sweep circuit and, 2. Thus, it is called Tunnel diode. This is done to order to allow the light energy to pass through it. Tunnel Diode Construction There are 2 terminals of diode first is positive called anode and second is negative called cathode. The heavy doping results in a broken band gap, where conduction band electron states on the N-side are more or less aligned with valence band hole states on the P-side. So, from A to B, the graph shows the negative resistance region of the tunnel diode. HISTORY • Tunnel Diode was invented in August 1957 by Leo Esaki. zenor diode working. The tunnel diode can be used as an amplifier and as an oscillator for detecting small high-frequency or as a switch. The P portion of the diode operates as anode and the N part is denoted as a cathode. Difference Between PN Junction & Zener Diode, Electron Hole Pairs Generation and Recombination, Difference Between Current Transformer (CT) & Potential Transformer (PT), Calibration of Voltmeter, Ammeter & Wattmeter using Potentiometer, Two Wattmeter Method of Power Measurement, Difference Between Conduction and Convection, Difference Between Circuit Switching and Packet Switching, Difference Between Static and Kinetic Friction, Difference Between Ductility and Malleability, Difference Between Physical and Chemical Change, Difference Between Alpha, Beta and Gamma Particles, Difference Between Electrolytes and Nonelectrolytes, Difference Between Electromagnetic Wave and Matter Wave. Privacy. 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