GATE EC 2014 Set 4 — Question 46
Go beyond PYQs with Success TrackerAI-powered personalised practice and doubt support. Unlimited practice on eligible plans; AI usage limits apply.MCQ+2 / -0.67MediumEnergy BandsSemiconductor PhysicsElectronic Devices
Electronic Devices → Semiconductor Physics → Energy Bands
Last updated
Question
An N-type semiconductor having uniform doping is biased as shown in the figure.
If is the lowest energy level of the conduction band, is the highest energy level of the valence band and is the Fermi level, which one of the following represents the energy band diagram for the biased N-type semiconductor?
Correct answer
(D) [figure]
Solution
1.Doping Type: The semiconductor is N-type, so the Fermi level must be closer to the conduction band than the valence band .
2.Bias Effect: A positive potential is applied to the left side, and the right side is grounded. Electrostatic potential decreases from left to right.
3.Energy Relation: Electron energy is . Therefore, a decrease in potential results in an increase in electron energy . The energy bands () must slope upwards from left to right.
4.Steady State Current: Under uniform bias and doping, a constant current flows. The electrochemical potential (Fermi level) must also slope to drive the current (). Thus, remains parallel to and .
Option (D) correctly shows N-type positioning ( near ) and the correct upward slope for all levels under the given bias.Continue learning with Success Tracker
A step still unclear? Work through it with support
Use Success Tracker to ask about the reasoning, then try another GATE EC question to check your understanding.
AI-powered practice· Unlimited practice on eligible plans
- PYQs with solutions
- Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
- Practice that adapts
- Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
- AI doubt support
- Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.
Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.
This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.
More questions on Semiconductor Physics
2026 Set 1 Q14Consider carrier transport in a Zener diode in the breakdown region. Which is the dominant…2026 Set 1 Q18Consider the circuit shown in the Figure with and . Assume…2026 Set 1 Q25Consider a p-n junction diode when it is forward biased with 2 V. Which of the following is/are the…2026 Set 1 Q29Figure shows the output characteristics of two different Bipolar Junction Transistors (BJT), BJT 1…2026 Set 1 Q54Consider an LED based on a direct bandgap semiconductor material with energy bandgap eV.…