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Resonant Tunneling Diodes (RTD)

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Concept of Resonant Tunneling An interesting phenomena occurs when two barriers of width a separated by a potential well of a small distance 𝐿 as shown in fig. This leads to the concept of resonant tunneling. Fig.: Double barrier junction with no applied bias.   The barriers are sufficiently thin to allow tunneling and the well region between the two barriers is also sufficiently narrow to form discrete (quasi-bound) energy levels. The transmission coefficient of the double symmetric barrier becomes unity. (ie., T = 1) , when the energy of the incoming electron wave ( 𝐸 ) coincides with the energy of one of the discrete states formed by the well. Thus, transmission probability of the double symmetric barrier is maximum; hence, the tunneling current reaches peak value when the electron wave's energy is equal to the well's quantized energy state. This phenomenon is known as resonance tu

MODEL QUESTION PAPER

  Subject: Nano Technology MODEL QUESTION PAPER Seventh Semester B.E. Degree Examination ECE BRANCH PART A MCQ (“ Multiple Choice Question .) 1.         Which one of the following is an advantage of nanotechnology? a)        Increased stability b)        Leakage of drug c)        Low solubility d)        All of the above 2.       What is Lithography? a)       Process used to transfer a pattern to a layer on the chip b)       Process used to develop an oxidation layer on the chip c)       Process used to develop a metal layer on the chip d)       Process used to produce the chip 3.       What is the standard form of SEM? a)        Scanning Electron Microscope b)        Scanning Electrode Microscope c)        Scanning Electrical Microscope d)        None of the above 4.       Which of the following application of tunnel diode has highest frequency of an solid based oscillator? a)       M